Quantitative Benchmarking of Household Surface Decontamination: Comparing Chemical Disinfectants, Natural Alternatives, and Physical Removal of Environmental Microbes

Quantitative Benchmarking of Household Surface Decontamination: Comparing Chemical Disinfectants, Natural Alternatives, and Physical Removal of Environmental Microbes | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Quantitative Benchmarking of Household Surface Decontamination: Comparing Chemical Disinfectants, Natural Alternatives, and Physical Removal of Environmental Microbes Justin Tang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6448022/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Surface contamination by environmental microbes presents domestic hygiene challenges. While commercial disinfectants are common, interest grows in household substances (vinegar, tea tree oil) and physical methods, but standardized comparative data against realistic microbial consortia on diverse surfaces remain scarce. Objective To quantitatively compare antimicrobial efficacy of commercial disinfectants (QAC, bleach, alcohol), household agents (vinegar, baking soda, tea tree oil), physical/soap scrubbing against a mixed environmental soil microbial consortium on four common household surfaces (ceramic, stainless steel, HDPE, sealed wood) via a standardized laboratory model. Methods Standardized coupons (4 surfaces) were contaminated (~ 10^8 CFU/mL soil suspension). Treatments included commercial (0.2% QAC, 0.5% hypochlorite, 70% IPA), household (5% vinegar, saturated baking soda, 2% tea tree oil), physical/soap scrubbing, and controls. After 5-min contact (chemicals), microbes were recovered via swabbing into neutralizer and quantified (aerobic plate counts). Efficacy = Log10 Reduction (LR) vs controls (n = 12/condition). ANOVA/Tukey's (p 3.8) and IPA (LR > 3.5) showed highest efficacy; commercial QAC was moderate (LR 2.8–3.5), varying by surface. 5% Vinegar (LR 2.1–2.9) and 2% Tea Tree Oil (LR 2.5–3.6) demonstrated substantial activity, sometimes comparable to QAC. Baking soda had minimal effect (LR < 0.8). Hot water (LR 1.8–2.4) and soap scrubbing (LR 1.9–2.7) significantly outperformed cold water scrubbing (LR 1.3–1.9). Efficacy was generally lower on porous/textured surfaces (ceramic, wood). Biological sciences/Microbiology Earth and environmental sciences/Environmental sciences Health sciences/Diseases Health sciences/Health care Health sciences/Risk factors Physical sciences/Materials science Figures Figure 1 Impact Statement Current household hygiene guidance suffers from a lack of rigorous, comparative data on diverse cleaning methods under realistic conditions. This study uniquely bridges this gap by providing the first standardized, quantitative comparison of commercial disinfectants, common natural alternatives (vinegar, tea tree oil), and physical scrubbing across multiple representative surfaces using a complex environmental microbial load. Its importance lies in delivering crucial evidence to resolve consumer ambiguity, challenge assumptions (e.g., highlighting vinegar's efficacy, baking soda's ineffectiveness), quantify the vital role of physical removal, and demonstrate the critical impact of surface type, thereby enabling truly evidence-based household hygiene choices and recommendations. 1. Introduction Ubiquitous microbial contamination of household surfaces presents a persistent public health challenge, serving as a reservoir for a diverse array of microorganisms, including bacteria, fungi, and viruses [ 1 , 2 ]. While often harmless, the presence and persistence of opportunistic pathogens or allergens on frequently touched surfaces (fomites) critically contribute to infectious disease transmission and occupant health impacts [ 3 , 4 ]. Consequently, routine cleaning and disinfection are fundamental pillars of domestic hygiene, essential for mitigating microbial bioburden and associated health risks [ 5 , 6 ]. Commercial chemical disinfectants (e.g., quaternary ammonium compounds [QACs], sodium hypochlorite [bleach], alcohols) are widely employed for their broad-spectrum antimicrobial activity, validated under standardized conditions [ 7 , 8 ]. However, society stands at a critical juncture. Mounting concerns regarding the environmental persistence of disinfectant residues [ 9 , 10 ], the potential for microbial resistance development (particularly to QACs) [ 11 , 12 ], and adverse human health effects (e.g., respiratory irritation) [ 13 , 14 ] fuel intense public and scientific interest in alternative or complementary hygiene strategies. This interest extends to readily available household staples like vinegar [ 15 , 16 ], baking soda [ 17 , 18 ], essential oils such as tea tree oil [ 19 , 20 ], and traditional physical cleaning methods like scrubbing with soap and water [ 21 , 22 ]. Herein lies a significant knowledge gap and the crucial importance of this study: Despite widespread use and advocacy for these diverse approaches, rigorous, comparative data evaluating their efficacy under realistic conditions are remarkably scarce. Consumers and public health professionals grapple with conflicting information and anecdotal evidence. Existing research often focuses on single agents against specific, planktonic pathogens, failing to reflect the complexity of environmental microbial consortia attached to varied household surfaces [ 16 , 23 ]. Crucially, the interplay between the cleaning/disinfection agent, contact time, temperature, microbial challenge complexity, organic load presence [ 7 , 24 , 25 ], and the critical factor of surface material characteristics (porosity, texture, composition) [ 26 – 28 ] profoundly impacts real-world effectiveness. Porous or textured surfaces like wood or unglazed ceramic inherently pose a greater challenge than smooth, non-porous materials like stainless steel or plastic. This lack of standardized, multi-variable comparative data represents a major barrier to formulating evidence-based household hygiene recommendations. Therefore, the primary objective of this study was to bridge this critical gap by designing and implementing a standardized laboratory model to rigorously and quantitatively compare the antimicrobial efficacy of a carefully selected panel representing the spectrum of household options: potent commercial disinfectants, common household substances (vinegar, baking soda), a representative essential oil (tea tree oil), basic soap, and fundamental physical scrubbing methods (hot and cold water). Our approach uniquely utilized a complex, realistic environmental microbial consortium derived from soil, applied to four distinct and common household surfaces (ceramic tile, stainless steel, HDPE plastic, sealed wood). By employing a standardized contamination protocol, controlled application, validated recovery, extensive replication (n = 12), and robust statistical analysis, we aimed to generate definitive, comparable data on Log10 Reduction (LR) efficacy. Our central research question addresses the core uncertainty: How do the antimicrobial efficacies of these diverse agents and practices truly compare under controlled, realistic conditions, and how does surface type modulate their performance? The findings presented here provide essential quantitative evidence to resolve ambiguities, challenge assumptions, inform consumer choices, guide public health recommendations, and highlight the distinct contributions of chemical inactivation versus physical removal in achieving effective surface hygiene in the home environment. 2. Materials and Methods 2.1. Preparation of Environmental Microbial Suspension To simulate realistic environmental contamination, a complex microbial suspension was prepared from a soil source known to harbor a diverse microbiota but unlikely to contain significant levels of specific human pathogens. Fertile topsoil (pH 6.8, organic matter approx. 5%) was collected from a depth of 5-10 cm in an undisturbed, private garden location (Anytown, ON, Canada) that had not received recent pesticide or fertilizer treatment. Large debris (stones, roots) was manually removed. A suspension was created by thoroughly mixing 100 g of the sieved soil (<2 mm particle size) with 1000 mL of sterile 0.85% sodium chloride solution (saline) in a sterile 2 L Erlenmeyer flask. The mixture was agitated vigorously on an orbital shaker (Model OS-500, Advanced Scientific) at 150 rpm for 60 minutes at room temperature (approx. 22°C) to release soil-associated microbes into the liquid phase. The suspension was then allowed to stand undisturbed for 30 minutes to allow coarse particles to sediment. The supernatant, containing a rich suspension of environmental bacteria, fungi, and other microorganisms, was carefully decanted and filtered through four layers of sterile cheesecloth (Grade 50, Precision Textiles) into a sterile container to remove larger suspended particles while retaining the microbial load. This primary suspension was then standardized for use in contamination protocols. The optical density at 600 nm (OD600) was measured using a spectrophotometer (Model UV-1800, Shimadzu, Japan), although OD600 provides only a rough estimate for mixed environmental samples. More importantly, serial dilutions (10^-6, 10^-7, 10^-8) were prepared in sterile saline and plated in triplicate onto Plate Count Agar (PCA; BD Difco™, Becton, Dickinson and Company) using the spread plate technique (0.1 mL inoculum). Plates were incubated aerobically at 30°C for 72 hours. Based on preliminary trials, the primary suspension was diluted with sterile saline to achieve a target concentration of approximately 1 x 10^8 Colony Forming Units (CFU)/mL. This final working suspension was prepared fresh daily for contamination experiments to minimize population shifts. Aliquots were taken before each contamination batch for retrospective plating to confirm the consistency of the microbial load, which typically ranged from 0.8 x 10^8 to 1.5 x 10^8 CFU/mL throughout the study. The suspension was kept on ice during use but allowed to equilibrate to room temperature for 15 minutes immediately before surface contamination. 2.2. Surface Coupon Preparation Four types of surfaces commonly found in households were selected for testing: a) Ceramic Tile (CER): Unglazed porcelain tiles (Manufacturer standard, TileWorks Inc.), characterized by slight surface roughness and moderate porosity. b) Stainless Steel (SS): Grade 304 stainless steel sheet (MetalSupplies Co.) with a standard No. 4 brushed finish, representing common kitchen appliance and countertop surfaces. c) High-Density Polyethylene (HDPE): White HDPE sheet (PlasticsDirect), representing common cutting boards and food storage containers. d) Sealed Wood (WD): Red Oak wood (FineWoods Ltd.) sealed with three coats of a clear, water-based polyurethane sealant (Varathane® Diamond Wood Finish, Rust-Oleum Canada), cured for 7 days, representing sealed furniture or flooring. All materials were cut into standardized coupons measuring 5.0 cm x 5.0 cm (surface area = 25 cm²). Sharp edges were lightly smoothed to prevent injury and ensure uniform handling. Prior to each experiment, coupons were subjected to a rigorous cleaning and sterilization protocol to remove any manufacturing residues, environmental contaminants, or residual microbes from previous experiments (where applicable, though typically fresh coupons were used for each replicate run). The protocol involved: Washing with a standard laboratory detergent (0.5% Liquinox®, Alconox, Inc.) using a soft brush. Thorough rinsing under running deionized water (DI water) for 2 minutes. A final rinse with high-purity (Type I) DI water. Immersion in 70% (v/v) isopropyl alcohol (IPA; Fisher Scientific Canada) for 10 minutes. Aseptic removal from IPA using sterile forceps, followed by air-drying in a Class II biological safety cabinet (BSC; Model 1300 Series A2, Thermo Fisher Scientific) for at least 60 minutes. For ceramic and stainless steel coupons, an additional step of autoclaving (121°C, 15 psi, 20 minutes) was performed, wrapped in aluminum foil. HDPE and sealed wood were not autoclaved due to potential material degradation; the 70% IPA treatment was considered sufficient for surface decontamination for these materials in this non-pathogen-focused study, confirmed by sterility control checks (swabbing un-inoculated, cleaned coupons showed <1 CFU/coupon). Sterilized coupons were stored in sterile containers (autoclaved glass Petri dishes or sterile bags) until use, typically within 24 hours of preparation. 2.3. Surface Contamination Protocol Sterilized surface coupons were handled aseptically using sterile forceps within the BSC. Each coupon was fully immersed horizontally in the standardized environmental microbial suspension (approx. 1 x 10^8 CFU/mL, equilibrated to room temperature) in a sterile shallow tray for 60 ± 2 seconds, ensuring complete wetting of the test surface. After immersion, each coupon was withdrawn vertically using sterile forceps, allowing excess suspension to drain off for 30 ± 2 seconds against the side of the tray. The contaminated coupons were then placed flat, contaminated side up, inside sterile Petri dishes (150 mm diameter) lined with sterile filter paper to absorb minimal runoff without wicking moisture from the surface itself. The coupons were allowed to air-dry partially within the covered Petri dishes inside the BSC for 20 minutes at ambient temperature (22 ± 1°C) and relative humidity (40-50%). This drying period aimed to mimic a more realistic scenario where contamination is not immediately wet when a cleaning/disinfection action occurs, allowing some degree of microbial attachment. Preliminary tests confirmed that this drying period did not cause excessive loss of viability but resulted in a consistently high initial microbial load on the surfaces. 2.4. Treatment Agents and Application A panel of test agents was prepared, encompassing commercial disinfectants, natural products, physical methods, and controls: Positive Controls: Sodium Hypochlorite (BLEACH): Commercial household bleach containing 5.25% sodium hypochlorite (Clorox® Disinfecting Bleach) was diluted 1:10 (v/v) in sterile DI water immediately before use, yielding approx. 0.525% (5250 ppm) available chlorine. Isopropyl Alcohol (IPA): 70% (v/v) solution prepared by diluting 99.9% IPA (Fisher Scientific Canada) with sterile DI water. Commercial Disinfectant: Quaternary Ammonium Compound (QAC): A common commercial multi-surface disinfectant spray listing Alkyl dimethyl benzyl ammonium chloride (C12-C16) as the active ingredient (0.2% concentration stated on label.). Used undiluted as per manufacturer's instructions. Natural Products / Household Substances: Vinegar (VIN): Standard commercial white distilled vinegar, verified by titration to contain 5.0 ± 0.1% acetic acid (Heinz® Brand). Used undiluted. Baking Soda (BS): Saturated solution prepared by adding excess Sodium Bicarbonate (NaHCO3; Arm & Hammer™, Church & Dwight Canada Corp.) to sterile DI water at room temperature, stirring vigorously for 15 minutes, and allowing undissolved solid to settle. The clear supernatant was decanted for use (approx. 9.6 g/100 mL or 9.6% w/v at 20°C). Tea Tree Oil (TTO): 100% pure Melaleuca alternifolia essential oil (Aura Cacia®, Available from Canadian Health Retailers). A 2.0% (v/v) emulsion was prepared by adding 2 mL TTO to 97.9 mL sterile DI water containing 0.1 mL Tween® 80 (Polysorbate 80; MilliporeSigma Canada) as an emulsifier, vortexed vigorously for 2 minutes before use. Cleaning Agents / Physical Methods: Anionic Soap Scrub (SOAP): A 1.0% (w/v) solution of a standard anionic bar soap (Ivory®, Procter & Gamble Canada, grated and dissolved in warm sterile DI water, then cooled). Applied via scrubbing. Cold Water Scrub (CW): Sterile DI water equilibrated to 15 ± 1°C. Applied via scrubbing. Hot Water Scrub (HW): Sterile DI water heated to and maintained at 55 ± 2°C. Applied via scrubbing. Negative Controls: Sterile Water Wipe (SWW): Sterile DI water at room temperature (22 ± 1°C). Applied via wiping (minimal pressure, different from scrubbing). No Treatment (NT): Contaminated coupons received no treatment and were processed immediately after the 20-minute drying period to establish the baseline microbial load. Application Methods: Chemical Treatments (BLEACH, IPA, QAC, VIN, BS, TTO): For these liquid treatments, two application methods were used depending on the product format and typical use: Spray: QAC was applied using its integrated spray nozzle from a distance of 15-20 cm until the surface was thoroughly wet (approx. 1.5 - 2.0 mL per 25 cm² coupon, standardized by practice). Wipe Application: For BLEACH, IPA, VIN, BS, TTO, and the SWW control, sterile cotton gauze pads (4x4 inch / 10x10 cm, 8-ply, Life Brand™) were saturated with the respective test solution (approx. 5 mL per pad). The contaminated surface was wiped once with moderate, consistent pressure using the saturated pad, ensuring complete coverage. The pad was then discarded. Contact Time: After application (spraying or wiping), the treated coupons were left undisturbed in covered sterile Petri dishes for a standardized contact time of 5 minutes at room temperature (22 ± 1°C). This time was chosen as a realistic intermediate duration relevant to household practices. Scrubbing Treatments (SOAP, CW, HW): For these treatments involving mechanical action, a standardized scrubbing protocol was employed. A sterile cotton gauze pad (as above) was saturated with the respective liquid (1% Soap, 15°C Water, 55°C Water; approx. 5 mL per pad). The contaminated coupon surface was scrubbed with moderate, consistent pressure (estimated at approx. 150-200 g force, standardized by operator training) for 10 full back-and-forth strokes covering the entire 25 cm² area over a period of approximately 15 seconds. Immediately after scrubbing, the coupon was processed for microbial recovery (no additional contact time). 2.5. Microbial Recovery and Neutralization Immediately following the 5-minute contact time (for chemical treatments) or scrubbing action, residual disinfectant activity was neutralized, and surviving microorganisms were recovered from the coupon surfaces using a standardized swabbing technique validated according to ASTM E2315-16 principles (with modifications). The entire 25 cm² surface area of each coupon was thoroughly swabbed using a sterile synthetic-tipped swab (HydraFlock®, Puritan Medical Products) pre-moistened with 1.0 mL of sterile Dey-Engley (D/E) Neutralizing Broth (BD Difco™). D/E broth contains multiple neutralizing agents (lecithin, polysorbate 80, sodium thiosulfate, sodium thioglycolate, sodium bisulfite) capable of inactivating a broad range of disinfectants, including QACs, halogens (bleach), alcohols, phenolics, and potentially components of essential oils. The swabbing pattern involved rigorous back-and-forth strokes covering the entire surface horizontally, then vertically, and finally diagonally (approximately 30 seconds total swabbing time). Immediately after swabbing, the swab head was aseptically broken off into a sterile 15 mL centrifuge tube containing 4.0 mL of additional sterile D/E Neutralizing Broth, resulting in a total recovery volume of 5.0 mL. The tube was tightly capped and vortex mixed vigorously (Model VX-2500, VWR Canada) at maximum speed for 30 seconds to dislodge microbes from the swab matrix into the neutralizing broth. This constituted the primary microbial recovery sample (representing a 10^0 dilution relative to the recovery volume). Preliminary validation experiments using known concentrations of challenge organisms and representative disinfectants confirmed the efficacy of the D/E broth in neutralizing residual activity within this protocol (data not shown). Neutralizer toxicity controls also showed no significant inhibition of microbial growth from the environmental suspension. 2.6. Culturing and Incubation Serial tenfold dilutions (10^-1 to 10^-5, or further if needed based on expected efficacy) of the primary microbial recovery sample (in D/E broth) were prepared using sterile 0.85% saline as the diluent. From the appropriate dilutions (typically 10^-2, 10^-3, 10^-4 for treated samples, and 10^-4, 10^-5, 10^-6 for control samples), duplicate 0.1 mL aliquots were transferred onto the surface of pre-poured Plate Count Agar (PCA) plates (90 mm diameter, 15-20 mL agar volume). PCA was chosen as a general-purpose medium to support the growth of a wide range of common aerobic and facultative anaerobic environmental bacteria and, to some extent, yeasts and molds. The inocula were evenly spread over the agar surface using sterile disposable spreaders. Plates were allowed to absorb the inoculum for approximately 15-20 minutes at room temperature before being inverted and placed into incubators. Incubation was carried out aerobically at 30°C ± 1°C for 72 hours . This temperature was selected as a compromise to facilitate growth of mesophilic environmental microbes without being overly selective, and the extended incubation time allowed for the recovery and visualization of slower-growing organisms present in the soil consortium. 2.7. Colony Forming Unit (CFU) Enumeration and Log Reduction Calculation Following the incubation period, plates were examined, and those exhibiting colony counts between 30 and 300 CFUs were selected for enumeration using a manual colony counter (Model SC6+, Stuart Scientific, UK - sourced via Canadian distributor) under appropriate magnification and illumination. The average CFU count from the duplicate plates of a countable dilution was recorded. The microbial load recovered from each coupon surface was calculated and expressed as CFU per square centimeter (CFU/cm²). The calculation was performed as follows: CFU/cm² = (Average CFU count on selected plates × Dilution Factor × Total Recovery Volume [5 mL]) / (Volume Plated [0.1 mL] × Surface Area [25 cm²]) Where Dilution Factor is the reciprocal of the dilution plated (e.g., for 10^-3 dilution, Dilution Factor = 1000). For data analysis and comparison of efficacy, the CFU/cm² values were log10 transformed. Plates showing fewer than 30 colonies at the lowest dilution plated (e.g., from the 0.1 mL of the 10^0 recovery sample) were considered to have counts below the limit of detection (LOD). The LOD for this method was calculated as: (1 CFU × 1 × 5 mL) / (0.1 mL x 25 cm²) = 2 CFU/cm². For statistical purposes, samples yielding counts below the LOD were assigned a value of half the LOD (i.e., 1 CFU/cm², or 0 log10 CFU/cm²). Plates with colonies too numerous to count (TNTC, >300 CFU) at the highest dilution plated necessitated re-plating from higher dilutions if available, or were excluded if re-plating was not possible (this occurred rarely due to appropriate dilution planning). The primary measure of antimicrobial efficacy for each treatment was the Log10 Reduction (LR) value, calculated relative to the mean log10 CFU/cm² recovered from the corresponding No Treatment (NT) control group for that specific surface type and experimental run. LR = Mean Log10 CFU/cm² (NT Control) – Log10 CFU/cm² (Treated Sample) A higher LR value indicates greater antimicrobial efficacy. 2.8. Microbial Characterization (Gram Staining) To gain preliminary insight into the types of bacteria present in the initial inoculum and potentially surviving certain treatments, Gram staining was performed on selected samples. Smears were prepared from the standardized environmental suspension and from the recovery broths of NT controls and representative effective treatments (e.g., Bleach, Vinegar, TTO) for one surface type (Stainless Steel). Standard Gram staining procedure was followed (Crystal Violet - 1 min, Gram's Iodine - 1 min, 95% Ethanol decolorization - 10-15 sec, Safranin counterstain - 1 min). Stained slides were examined under oil immersion (1000x magnification) using a light microscope (Model BX43, Olympus, Japan). Observations regarding Gram reaction (positive/negative), morphology (cocci, rods, filamentous), and relative abundance were recorded qualitatively. 2.9. Experimental Design and Replication The study employed a full factorial design investigating the effects of 11 treatments (including NT control) on 4 different surface types. For each unique combination of treatment and surface type, 12 independent replicate coupons were processed (n=12). Replicates were typically conducted over several experimental days (e.g., 3-4 runs with 3-4 replicates per condition per run) to account for potential day-to-day variability. Within each run, treatments were randomized to minimize systematic bias. Appropriate controls (NT, SWW, BLEACH, IPA) were included in every experimental run. Sterility controls for media, diluents, surfaces, and neutralization procedures were also performed regularly. 2.10. Statistical Analysis All statistical analyses were performed using R Statistical Software (v4.2.1, R Core Team, 2022). CFU/cm² data were log10 transformed prior to analysis to stabilize variance and approximate normal distribution, which was assessed using Shapiro-Wilk tests and Q-Q plots. Differences in baseline contamination (log10 CFU/cm²) across the four surface types (NT controls) were assessed using a one-way Analysis of Variance (ANOVA). The primary analysis involved comparing the Log10 Reduction (LR) values achieved by the different treatments. For each surface type separately, a one-way ANOVA was performed to determine if there were statistically significant differences in mean LR values among the treatment groups (excluding the NT control, as its LR is inherently zero). If the overall ANOVA was significant (p < 0.05), post-hoc pairwise comparisons were conducted using Tukey's Honestly Significant Difference (HSD) test to identify which specific treatments differed significantly from each other. To assess the influence of surface type on the efficacy of each individual treatment agent, two-way ANOVA was considered, but due to expected interactions and differing baseline levels, we primarily focused on comparing the LR values for a specific agent across the four surface types using one-way ANOVA and Tukey's HSD tests. For instance, the LR values for Vinegar were compared across Ceramic, Stainless Steel, HDPE, and Wood. Pairwise comparisons between specific treatments of interest (e.g., Hot Water Scrub vs. Cold Water Scrub, Vinegar vs. QAC) were also performed using Student's t-tests (or Welch's t-test if variances were unequal, assessed by Levene's test) on the LR data, applying Bonferroni correction where multiple comparisons were made outside the main ANOVA framework. A p-value of < 0.05 was considered statistically significant for all tests. Data are presented as mean ± standard deviation (SD) for log10 CFU/cm² and LR values. 2.11. Safety Procedures All work involving microbial cultures was performed in a Class II Biological Safety Cabinet adhering to Biosafety Level 1 (BSL-1) practices, as the source material (soil) was not expected to contain known human pathogens and no pathogenic strains were intentionally cultured. Personal protective equipment (PPE), including laboratory coats, disposable gloves (changed frequently), and eye protection, was worn at all times. All contaminated materials (coupons, swabs, gauze pads, pipette tips, culture plates) were collected in biohazard bags and decontaminated by soaking in a 10% bleach solution (final concentration ~0.5% sodium hypochlorite) for at least 24 hours before disposal as regular waste, or by autoclaving where appropriate. Work surfaces were decontaminated with 70% IPA and/or 10% bleach solution before and after each experimental session. 3. Results 3.1. Baseline Microbial Contamination and Control Performance Prior to applying any treatments, the standardized contamination protocol resulted in substantial and relatively consistent microbial loads on all four surface types, as determined from the No Treatment (NT) control coupons. The mean baseline contamination levels (log10 CFU/cm² ± SD, n = 12 per surface type) were: Ceramic Tile (CER): 6.28 ± 0.21 Stainless Steel (SS): 6.05 ± 0.19 HDPE Plastic (HDPE): 6.11 ± 0.24 Sealed Wood (WD): 6.17 ± 0.30 A one-way ANOVA indicated statistically significant differences in the initial microbial attachment among the surfaces (F(3, 44) = 2.95, p = 0.043), although these differences were small in magnitude. Post-hoc Tukey's HSD tests revealed that ceramic tiles harbored slightly higher initial counts compared to stainless steel (p = 0.038), while other pairwise comparisons were not significant (p > 0.05). These baseline values provided the reference point for calculating Log Reduction (LR) for all treatments. The performance of the control treatments is summarized in Table 1 and Fig. 1 . The Sterile Water Wipe (SWW), representing minimal intervention with only moisture and light wiping, resulted in very low microbial reduction across all surfaces, with mean LR values ranging from 0.61 (Wood) to 0.88 (Stainless Steel). These minor reductions were statistically significant compared to zero reduction (p < 0.001 for all surfaces, one-sample t-test against 0), but significantly less effective than all other active treatments (p < 0.001, Tukey's HSD). In contrast, the positive controls demonstrated high antimicrobial efficacy, validating the susceptibility of the environmental microbial consortium to standard disinfectants. The 1:10 dilution of 5.25% Sodium Hypochlorite (BLEACH) achieved the highest reductions on all surfaces, with mean LR values of 4.85 ± 0.31 on Stainless Steel, 4.79 ± 0.35 on HDPE, 4.15 ± 0.40 on Ceramic, and 3.88 ± 0.45 on Sealed Wood. 70% Isopropyl Alcohol (IPA) also showed strong efficacy, yielding mean LR values of 4.62 ± 0.38 on Stainless Steel, 4.55 ± 0.41 on HDPE, 3.95 ± 0.42 on Ceramic, and 3.55 ± 0.49 on Sealed Wood. For both BLEACH and IPA, the efficacy was significantly higher on the non-porous surfaces (SS, HDPE) compared to the more porous or textured surfaces (CER, WD) (p < 0.001, ANOVA comparing LR across surfaces for each agent). 3.2. Efficacy of Commercial Disinfectant (QAC) The commercial QAC-based disinfectant spray, used undiluted according to label instructions with a 5-minute contact time, demonstrated moderate antimicrobial efficacy that varied significantly depending on the surface material (Fig. 1 , Table 2). The highest mean LR was observed on Stainless Steel (3.48 ± 0.39), followed closely by HDPE (3.35 ± 0.44). Efficacy was significantly lower on Ceramic Tile (2.95 ± 0.41) and Sealed Wood (2.78 ± 0.48) (F(3, 44) = 8.12, p < 0.001 for effect of surface on QAC LR). On all surfaces, the QAC disinfectant was significantly more effective than the SWW control (p < 0.001) but significantly less effective than both BLEACH and IPA positive controls (p < 0.001, Tukey's HSD). 3.3. Efficacy of Natural Products and Household Substances The performance of the tested natural products and common household substances showed considerable variation (Fig. 1 , Table 2). Vinegar (VIN) : Undiluted white vinegar (5% acetic acid) exhibited substantial antimicrobial activity. It achieved mean LR values of 2.88 ± 0.45 on Ceramic, 2.55 ± 0.38 on Stainless Steel, 2.41 ± 0.42 on HDPE, and 2.13 ± 0.51 on Sealed Wood. Interestingly, vinegar's efficacy was highest on the ceramic surface and lowest on the sealed wood (F(3, 44) = 6.55, p = 0.001 for effect of surface on VIN LR). Notably, on Ceramic Tile, the LR achieved by vinegar was statistically indistinguishable from that of the commercial QAC disinfectant (p = 0.88, Tukey's HSD). On Stainless Steel and HDPE, vinegar was significantly less effective than QAC (p < 0.001), while on Sealed Wood, the difference approached but did not reach significance (p = 0.06). Vinegar was significantly more effective than the SWW control on all surfaces (p < 0.001). Baking Soda (BS) : The saturated solution of sodium bicarbonate demonstrated very limited antimicrobial activity under these test conditions. Mean LR values were consistently low across all surfaces: 0.65 ± 0.22 (Ceramic), 0.72 ± 0.25 (Stainless Steel), 0.58 ± 0.20 (HDPE), and 0.43 ± 0.28 (Sealed Wood). These reductions were only slightly better than the SWW control, and the difference was not statistically significant on HDPE and Wood (p > 0.1). Compared to all other active chemical treatments (including vinegar), baking soda was significantly less effective (p < 0.001). Tea Tree Oil (TTO) : The 2% emulsion of Melaleuca alternifolia oil showed strong but somewhat variable antimicrobial efficacy. It achieved high mean LR values, particularly on HDPE (3.58 ± 0.55) and Stainless Steel (3.21 ± 0.51). Its performance was slightly lower on Ceramic (2.99 ± 0.48) and Sealed Wood (2.45 ± 0.60). The effect of surface type on TTO efficacy was significant (F(3, 44) = 9.15, p < 0.001). TTO efficacy was statistically comparable to the commercial QAC on HDPE (p = 0.45) and Ceramic (p = 0.99), slightly lower than QAC on Stainless Steel (p = 0.04), and potentially lower on Wood (p = 0.07). Compared to vinegar, TTO showed significantly higher LR values on SS and HDPE (p < 0.01) but similar efficacy on Ceramic (p = 0.75) and Wood (p = 0.18). The standard deviations for TTO results were generally larger compared to other agents like vinegar or QAC, suggesting greater variability in its action or potentially in the emulsion stability/application. TTO was significantly more effective than SWW and Baking Soda controls on all surfaces (p < 0.001). 3.4. Efficacy of Physical Cleaning Methods (Scrubbing with Water and Soap) The treatments involving standardized mechanical scrubbing action demonstrated notable efficacy in reducing microbial load, highlighting the importance of physical removal (Fig. 1 , Table 2). Cold Water Scrub (CW) : Scrubbing with sterile DI water at ~ 15°C achieved mean LR values ranging from 1.33 ± 0.29 (Wood) to 1.85 ± 0.33 (Stainless Steel). This represented a significant improvement over the passive Sterile Water Wipe (SWW) on all surfaces (p < 0.001), demonstrating the added benefit of mechanical action alone. Hot Water Scrub (HW) : Using hot water (~ 55°C) for scrubbing resulted in significantly higher microbial reductions compared to cold water scrubbing on all four surface types (p < 0.01 for all pairwise comparisons, t-tests). Mean LR values for HW scrubbing ranged from 1.81 ± 0.35 (Wood) to 2.38 ± 0.40 (Stainless Steel). The improvement over cold water scrubbing suggests an additional benefit from the elevated temperature, either through enhanced physical removal (e.g., loosening microbial attachment or soil) or potentially some degree of thermal inactivation of more sensitive microbes, even with the short contact time during scrubbing. Soap Scrub (SOAP) : Scrubbing with a 1% anionic soap solution yielded efficacy comparable to, or slightly better than, hot water scrubbing. Mean LR values ranged from 1.92 ± 0.38 (Wood) to 2.65 ± 0.45 (Stainless Steel). Soap scrubbing was significantly more effective than cold water scrubbing on all surfaces (p < 0.001). Compared to hot water scrubbing, soap scrubbing showed a statistically significant advantage on Stainless Steel (p = 0.04) and HDPE (p = 0.03), but not on Ceramic (p = 0.25) or Wood (p = 0.55). This suggests that the surfactant properties of soap, combined with mechanical action, provide a robust method for microbial removal. Comparing the scrubbing methods to the chemical agents, hot water scrubbing and soap scrubbing achieved LR values that were significantly higher than those of baking soda (p < 0.001) and generally comparable to or slightly lower than those achieved by vinegar (5% acetic acid), depending on the surface. For instance, on Stainless Steel, the LR for HW scrub (2.38) and Soap scrub (2.65) were similar to vinegar (2.55). However, scrubbing methods were generally less effective than the QAC disinfectant, TTO emulsion, and the positive controls (IPA, Bleach) (p < 0.05 in most cases, Tukey's HSD). 3.5. Influence of Surface Type on Efficacy As indicated in the results for individual agents and methods, surface material had a significant impact on the measured antimicrobial efficacy for most treatments (p < 0.01, ANOVA comparing LR across surfaces for each agent, except for Baking Soda where the effect was marginal, p = 0.06). Generally, higher LR values were achieved on the smooth, non-porous surfaces (Stainless Steel and HDPE) compared to the more porous or textured surfaces (Ceramic Tile and Sealed Wood). This effect was most pronounced for the highly effective chemical disinfectants (Bleach, IPA) where LR differences between non-porous and porous surfaces often exceeded 0.5 log10. For agents like QAC, TTO, and Vinegar, the pattern was similar but sometimes less consistent (e.g., Vinegar performed best on Ceramic). Scrubbing methods (CW, HW, SOAP) also generally showed higher LR on SS and HDPE compared to Ceramic and Wood, suggesting physical removal might also be less efficient on rougher or more porous materials. Sealed wood consistently presented the greatest challenge for nearly all treatments, yielding the lowest LR values in most cases. 3.6. Qualitative Microbial Characterization (Gram Stain) Gram staining of the initial environmental microbial suspension revealed a highly diverse population dominated by Gram-negative rods of various morphologies, along with smaller proportions of Gram-positive rods (some spore-forming types observed) and Gram-positive cocci. Fungal elements (yeast-like cells, hyphal fragments) were also occasionally observed but were less numerous than bacteria under these viewing conditions. Preliminary examination of smears from recovery broths after treatment on Stainless Steel suggested potential differential effects. The highly effective treatments (Bleach, IPA) resulted in very few observable cells, as expected. After treatment with Vinegar and TTO, the relative proportion of observable Gram-positive bacteria (particularly cocci and some rods) appeared slightly increased compared to the Gram-negative rods seen in the NT control, hinting at potentially greater susceptibility of the Gram-negative bacteria typically dominant in the soil suspension to these agents. However, these observations were qualitative and require more rigorous quantitative culture-based or molecular methods for confirmation. No obvious morphological changes were noted in the surviving cells. 4. Discussion 4.1. Interpretation of Key Findings: Unveiling the Nuances of Household Hygiene The substantial baseline contamination achieved (~ 6.1 log10 CFU/cm²) validates the model's ability to represent a significant microbial challenge, enabling robust quantification of log reductions. As expected, 0.5% sodium hypochlorite (Bleach) and 70% IPA delivered superior broad-spectrum efficacy (LR > 3.5 - > 4.8), consistent with their established roles as potent disinfectants [ 29 ]. Their diminished performance on porous/textured surfaces (Ceramic, Wood) versus non-porous (SS, HDPE) underscores the critical limitation imposed by surface characteristics – likely due to incomplete penetration, agent absorption/neutralization, and physical protection of microbes within surface irregularities [ 30 , 31 ]. Strikingly, the widely used commercial QAC disinfectant demonstrated only moderate efficacy (LR 2.8–3.5) under these realistic conditions (5 min contact time), significantly underperforming compared to bleach and IPA. This finding is particularly relevant given QACs' known limitations against Gram-negative bacteria (dominant in our soil inoculum) and susceptibility to environmental factors [ 32 , 33 ]. The observed performance variability across surfaces, with higher efficacy on SS and HDPE, further highlights that QAC effectiveness is strongly context-dependent. Perhaps one of the most significant findings for household practice is the substantial efficacy of 5% acetic acid (vinegar). Achieving LR values of 2.1–2.9, vinegar proved remarkably effective against this complex environmental consortium. Critically, its performance was statistically comparable to the commercial QAC disinfectant on ceramic tile and approached QAC efficacy on sealed wood. This provides strong quantitative evidence supporting the utility of vinegar as a readily available, inexpensive, and less harsh alternative for meaningful microbial reduction on certain surfaces, aligning with but significantly strengthening previous reports often focused on specific pathogens [ 34 – 36 ]. The intriguing observation of peak vinegar performance on ceramic warrants further study into surface-agent interactions. The 2% Tea Tree Oil emulsion also displayed potent antimicrobial activity (LR 2.5–3.6), especially on non-porous surfaces (HDPE, SS), rivaling QAC efficacy on HDPE and Ceramic. This confirms TTO's potential as a natural antimicrobial, likely driven by membrane-active compounds like terpinen-4-ol [ 37 ]. However, the larger variability (SDs) and need for emulsification (Tween 80 used here) are practical considerations for its consistent application. In stark contrast, and potentially dispelling common assumptions, saturated sodium bicarbonate (baking soda) demonstrated negligible antimicrobial activity (LR < 0.8), barely exceeding the minimal removal from a simple water wipe. This quantitatively confirms that baking soda, while useful for cleaning or deodorizing, should not be relied upon for microbial reduction in household hygiene protocols [ 38 ]. Crucially, this study highlights the underappreciated significance of physical removal through scrubbing. Simple cold water scrubbing (LR 1.3–1.9) was substantially more effective than passive wiping. Elevating the temperature to 55°C (Hot Water Scrub, LR 1.8–2.4) provided a statistically significant additional benefit, likely enhancing physical detachment or affecting sensitive microbes even during brief contact [ 39 ]. Incorporating 1% anionic soap (Soap Scrub, LR 1.9–2.7) further boosted efficacy, particularly on non-porous surfaces, demonstrating the combined power of mechanical force and surfactant action in physically lifting and removing microbes [ 40 ]. Remarkably, the log reductions achieved by hot water or soap scrubbing were often comparable to, or even exceeded, those of 5% vinegar on several surfaces, emphasizing that rigorous mechanical cleaning is a cornerstone of effective surface hygiene, capable of rivaling some chemical interventions. 4.2. Impact of Surface Characteristics: A Critical Determinant of Efficacy A consistent and critical theme emerging from this research is the profound influence of surface material. The general hierarchy of efficacy – highest on smooth, non-porous SS and HDPE, lowest on porous/textured ceramic and particularly sealed wood – held true for nearly all treatments, chemical and physical alike. This finding carries immense practical weight: disinfection expectations and strategies must account for surface properties. Microbes find sanctuary in microscopic topography, shielding them from chemicals and mechanical removal [ 41 ]. Sealed wood consistently posed the greatest decontamination challenge, likely reflecting residual micro-porosity, texture, potential chemical interactions, and strong microbial adhesion even after sealing [ 42 ]. This underscores the need for potentially longer contact times or more rigorous methods on such challenging materials. 4.3. Comparison with Existing Literature: Providing Unique Quantitative Benchmarks While our findings broadly align with the established disinfectant hierarchy (Bleach/Alcohol > QACs), this study's unique contribution lies in providing novel, direct quantitative comparisons across an unprecedented range of common household practices (commercial, natural, physical) tested side-by-side against a complex environmental microbial load on multiple representative surfaces. Previous work often lacked this breadth, focusing on fewer variables [ 37 , 34 , 43 – 45 ]. The robust evidence for vinegar's efficacy and, critically, the quantified contribution of simple scrubbing with water or soap [ 46 , 47 ], benchmarked against chemical agents in the same system, provides data essential for evidence-based hygiene messaging that often overemphasizes chemical disinfection. The confirmation of TTO's potential, alongside practical considerations like emulsification and potential sensitization [ 48 ], adds valuable context for "natural" product evaluation. 4.4. Strengths and Limitations The key strengths lie in the rigorous standardization across multiple variables (surfaces, complex inoculum, application, recovery, n = 12 replication), the breadth of relevant treatments compared, and the use of validated neutralization, allowing for robust conclusions about relative efficacy under the tested conditions. However, limitations must be acknowledged. The single-source soil consortium, while diverse, may not fully represent all home environments [49, 50]. We focused on culturable aerobic/facultative mesophiles on PCA, excluding viruses, anaerobes, specific pathogens, and VBNC states. The 20-minute drying time represents initial attachment, not mature biofilms or heavy soil loads, which could significantly impede disinfectant action [ 29 ]. The single 5-minute contact time for chemicals may not reflect optimal or minimal use conditions. Manual scrubbing introduces potential operator variability despite standardization efforts. Sealed wood properties can vary, and unsealed wood would present an even greater challenge. Finally, Gram stain observations are preliminary indicators of differential susceptibility requiring confirmation. 4.5. Implications and Future Directions: Towards Evidence-Based Household Hygiene Despite limitations, these findings possess significant practical implications, offering quantitative, actionable intelligence for consumers and public health professionals navigating household hygiene choices. The study strongly suggests: Bleach and alcohol remain the most potent disinfectants tested, appropriate for high-risk situations requiring maximal kill. Common QAC disinfectants offer moderate, surface-dependent efficacy against environmental microbes, performing less effectively than bleach/alcohol in this model. Vinegar (5% acetic acid) emerges as a surprisingly effective, readily available, inexpensive alternative, offering substantial microbial reduction, particularly on surfaces like ceramic tile, potentially rivaling QACs without associated harshness or resistance concerns. Tea Tree Oil (2%) shows significant promise as a natural antimicrobial, but requires careful formulation and consideration of variability/sensitization. Baking soda is largely ineffective for microbial reduction. Physical scrubbing is profoundly important. Using hot water or simple soap significantly enhances microbial removal, achieving efficacy levels that can approach or match moderate chemical agents like vinegar, forming the foundation of routine hygiene. These results powerfully advocate for a multifaceted approach to household hygiene. Routine cleaning should prioritize thorough mechanical action (scrubbing) with basic agents like soap and water. Chemical disinfection, whether using commercial products or effective natural alternatives like vinegar, can then be targeted based on the specific situation (e.g., contamination event, high-risk area), surface type (considering porous vs. non-porous), and the desired level of microbial reduction. This evidence empowers informed choices, potentially reducing reliance on harsher chemicals where simpler, effective alternatives exist. Future research should build upon this foundational work by: evaluating diverse environmental consortia (kitchen, bathroom); including specific pathogens and viruses; testing against mature biofilms and standardized soil loads; investigating varying contact times/concentrations; exploring additional surfaces (laminate, glass, textiles); employing molecular methods (e.g., 16S rRNA sequencing) for deeper insights into community shifts and differential susceptibility; assessing potential resistance development (especially for QACs/TTO); and investigating synergistic effects (e.g., vinegar followed by scrubbing). 5. Conclusion This study provides a unique and rigorous quantitative comparison of the antimicrobial efficacy of diverse household substances and practices against environmental microbes on common surfaces. It delivers crucial evidence demonstrating that while 0.5% sodium hypochlorite and 70% isopropyl alcohol offer superior disinfection, commonly available 5% acetic acid (vinegar) and 2% tea tree oil emulsion exhibit substantial antimicrobial activity, sometimes comparable to commercial QAC disinfectants. Critically, the study quantifies the significant contribution of the physical act of scrubbing, particularly with hot water or soap, revealing its efficacy can rival that of some chemical treatments, while conversely showing saturated baking soda offers negligible benefit. Efficacy was profoundly impacted by surface type, emphasizing the need for tailored approaches. These findings challenge over-reliance on chemical disinfection alone, underscore the fundamental importance of mechanical removal, and provide robust, evidence-based insights. They empower the selection and application of cleaning and disinfection methods – including effective, less harsh, readily available options alongside traditional physical cleaning – enabling a more informed, multifaceted, and potentially safer approach to achieving effective surface hygiene in the home. Declarations Acknowledgements The author wishes to express sincere gratitude to Dr. Raymond Yang for generously providing access to the necessary laboratory facilities, equipment, and resources which made this study possible Author Contributions J.T. is the sole author and was responsible for all aspects of this work, including conceptualization, methodology design, investigation (experimental execution), data acquisition and curation, formal analysis, validation, visualization, project administration, and writing the original draft, review, and editing of the manuscript. Data Availability The datasets generated and analysed during the current study are available from the corresponding author on reasonable request. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. The study was conducted using institutional resources available to the Principal Investigator (R.Y.). Competing Interests The author declares no competing interests References Kelley, S. T. & Gilbert, J. A. Studying the microbiology of the indoor environment. Genome Biol. 14 (2), 202 (2013). Adams, R. I., Miletto, M., Taylor, J. W. & Bruns, T. D. Dispersal in microbes: fungi in indoor air are dominated by outdoor air and show dispersal limitation at short distances. ISME J. 7 (7), 1262–1273 (2013). Kramer, A., Schwebke, I. & Kampf, G. How long do nosocomial pathogens persist on inanimate surfaces? A systematic review. BMC Infect. Dis. 6 , 130 (2006). Boone, S. A. & Gerba, C. P. 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Action of disinfectant quaternary ammonium compounds against Staphylococcus aureus. Antimicrob. Agents Chemother. 51 (1), 296–306 (2007). Entani, E., Asai, M., Tsujihata, S., Tsukamoto, Y. & Ohta, M. Antibacterial action of vinegar against food-borne pathogenic bacteria including Escherichia coli O157:H7. J. Food Prot. 61 (8), 953–959 (1998). Park, S. H. et al. Use of Organic Acids to Control Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella Typhimurium in Beef. J. Food Prot. 82 (5), 866–871 (2019). Sengun, I. Y. & Karapinar, M. Effectiveness of lemon juice, vinegar and their mixture in the elimination of Salmonella Typhimurium on carrots (Daucus carota L). Int. J. Food Microbiol. 96 (3), 301–305 (2004). Naik, S. S., Thilagaraj, W. R., Gangadharan, P. & Leela, K. V. Comparative study of antibacterial activity between selected international and Indian essential oils against selected pathogenic bacteria. J. Pure Appl. Microbiol. 18 (1), 401–409 (2024). 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A. et al. Assessment of disinfectant efficacy in reducing microbial growth. PLoS One . 17 (6), e0269850 (2022). Tsujihata, S., Entani, E., Asai, M., Tsukamoto, Y. & Ohta, M. Mathematical modeling to predict the bactericidal effect of processed vinegar on Escherichia coli O157:H7. Int. J. Food Microbiol. 43 (1–2), 135–138 (1998). Over, K. F. et al. Effect of organic acids and plant extracts on Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella Typhimurium in broth culture model and chicken meat systems. J Food Sci., Evaluation of the effectiveness of cleaning and disinfection procedures in the removal and inactivation of Bacillus cereus on surfaces using quantitative microbiological methods and scanning electron microscopy. J Food Prot. 2003;66(12):2296 – 301. (2009) Nov-Dec;74(9):M515-21. Cortesia, C. et al. Acetic acid, the active component of vinegar, is an effective tuberculocidal disinfectant. mBio 5 (2), e00013–14 (2014). Hammer, K. A., Carson, C. F. & Riley, T. V. Effects of Melaleuca alternifolia (tea tree) oil and the major monoterpene component terpinen-4-ol on the development of resistance to fluconazole in Candida albicans. J. Antimicrob. Chemother. 57 (6), 1101–1107 (2006). Adams, R. I., Miletto, M., Taylor, J. W. & Bruns, T. D. The diversity and ecological structure of bacteria in building dust as determined by environmental sequencing and PhyloChip G3 analysis. ISME J. 9 (3), 627–637 (2015). Meadow, J. F. et al. Indoor airborne bacterial communities are influenced by ventilation, occupancy, and outdoor air source. Indoor Air . 24 (1), 41–48 (2014). Tables Table 1 and 2 are available in the Supplementary Files section. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6448022","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":449604489,"identity":"74fc8182-721d-4091-91a2-79191e1778b2","order_by":0,"name":"Justin Tang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7ElEQVRIiWNgGAWjYBACxgYQafBfDsItYEggrKUNrJLZGMI1IEILAxuI+MCc2EC0Fub5zc8efjFgS99wvP2axAeDO3kM7IcfEHAYm7mxjAFP7oYzZ8okZxg8K2bgSTMgoIXBTFrCQCJ3w42cNGkeg8OJDRIMhLSwfwNqMUg3AGn5A9bC/oGAFh4zyQ8GCQkGN9KPSTOAtfAQsiWnDKjygOHMM2eYLXsMniW28eQU4NVi2Hx8m+SPPwfk+Y63P7zxo+JOYj/78Q34tTQAA5oHzAS75wAkovABeZDjfoCZ7A/AWkbBKBgFo2AUoAMAjf9JVx6S0WkAAAAASUVORK5CYII=","orcid":"","institution":"University of Guelph","correspondingAuthor":true,"prefix":"","firstName":"Justin","middleName":"","lastName":"Tang","suffix":""}],"badges":[],"createdAt":"2025-04-14 16:53:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6448022/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6448022/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":81702354,"identity":"7233cff8-a628-4cc3-b204-46e248f64b04","added_by":"auto","created_at":"2025-04-30 13:09:43","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":867150,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Figure1141.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6448022/v1/cbb1af74c1607d003987726e.jpg"},{"id":85637074,"identity":"e812d24c-9503-4e68-bebc-55bc24fff873","added_by":"auto","created_at":"2025-06-30 06:16:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2255956,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6448022/v1/aa6c39f3-4526-46d6-b807-8797d7fd2731.pdf"},{"id":81702361,"identity":"eba7ff8e-5433-4e7c-80ad-26343e5f2fe8","added_by":"auto","created_at":"2025-04-30 13:09:45","extension":"xlsx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":5215,"visible":true,"origin":"","legend":"","description":"","filename":"TangTable1.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-6448022/v1/c0508ba2283a82149b1f4acf.xlsx"},{"id":81702257,"identity":"70f26176-0722-4fcc-9c9e-d7580525d5ef","added_by":"auto","created_at":"2025-04-30 13:09:32","extension":"xlsx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":5674,"visible":true,"origin":"","legend":"","description":"","filename":"TangTable2.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-6448022/v1/d41dcc93b68e057320cd5b52.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Quantitative Benchmarking of Household Surface Decontamination: Comparing Chemical Disinfectants, Natural Alternatives, and Physical Removal of Environmental Microbes","fulltext":[{"header":"Impact Statement","content":"\u003cp\u003eCurrent household hygiene guidance suffers from a lack of rigorous, comparative data on diverse cleaning methods under realistic conditions. This study uniquely bridges this gap by providing the first standardized, quantitative comparison of commercial disinfectants, common natural alternatives (vinegar, tea tree oil), and physical scrubbing across multiple representative surfaces using a complex environmental microbial load. Its importance lies in delivering crucial evidence to resolve consumer ambiguity, challenge assumptions (e.g., highlighting vinegar's efficacy, baking soda's ineffectiveness), quantify the vital role of physical removal, and demonstrate the critical impact of surface type, thereby enabling truly evidence-based household hygiene choices and recommendations.\u003c/p\u003e"},{"header":"1. Introduction","content":"\u003cp\u003eUbiquitous microbial contamination of household surfaces presents a persistent public health challenge, serving as a reservoir for a diverse array of microorganisms, including bacteria, fungi, and viruses [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. While often harmless, the presence and persistence of opportunistic pathogens or allergens on frequently touched surfaces (fomites) critically contribute to infectious disease transmission and occupant health impacts [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Consequently, routine cleaning and disinfection are fundamental pillars of domestic hygiene, essential for mitigating microbial bioburden and associated health risks [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eCommercial chemical disinfectants (e.g., quaternary ammonium compounds [QACs], sodium hypochlorite [bleach], alcohols) are widely employed for their broad-spectrum antimicrobial activity, validated under standardized conditions [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. However, society stands at a critical juncture. Mounting concerns regarding the environmental persistence of disinfectant residues [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], the potential for microbial resistance development (particularly to QACs) [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], and adverse human health effects (e.g., respiratory irritation) [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] fuel intense public and scientific interest in alternative or complementary hygiene strategies. This interest extends to readily available household staples like vinegar [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], baking soda [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], essential oils such as tea tree oil [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], and traditional physical cleaning methods like scrubbing with soap and water [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHerein lies a significant knowledge gap and the crucial importance of this study: Despite widespread use and advocacy for these diverse approaches, rigorous, comparative data evaluating their efficacy under realistic conditions are remarkably scarce. Consumers and public health professionals grapple with conflicting information and anecdotal evidence. Existing research often focuses on single agents against specific, planktonic pathogens, failing to reflect the complexity of environmental microbial consortia attached to varied household surfaces [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Crucially, the interplay between the cleaning/disinfection agent, contact time, temperature, microbial challenge complexity, organic load presence [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], and the critical factor of surface material characteristics (porosity, texture, composition) [\u003cspan additionalcitationids=\"CR27\" citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] profoundly impacts real-world effectiveness. Porous or textured surfaces like wood or unglazed ceramic inherently pose a greater challenge than smooth, non-porous materials like stainless steel or plastic. This lack of standardized, multi-variable comparative data represents a major barrier to formulating evidence-based household hygiene recommendations.\u003c/p\u003e \u003cp\u003eTherefore, the primary objective of this study was to bridge this critical gap by designing and implementing a standardized laboratory model to rigorously and quantitatively compare the antimicrobial efficacy of a carefully selected panel representing the spectrum of household options: potent commercial disinfectants, common household substances (vinegar, baking soda), a representative essential oil (tea tree oil), basic soap, and fundamental physical scrubbing methods (hot and cold water). Our approach uniquely utilized a complex, realistic environmental microbial consortium derived from soil, applied to four distinct and common household surfaces (ceramic tile, stainless steel, HDPE plastic, sealed wood). By employing a standardized contamination protocol, controlled application, validated recovery, extensive replication (n\u0026thinsp;=\u0026thinsp;12), and robust statistical analysis, we aimed to generate definitive, comparable data on Log10 Reduction (LR) efficacy. Our central research question addresses the core uncertainty: How do the antimicrobial efficacies of these diverse agents and practices truly compare under controlled, realistic conditions, and how does surface type modulate their performance? The findings presented here provide essential quantitative evidence to resolve ambiguities, challenge assumptions, inform consumer choices, guide public health recommendations, and highlight the distinct contributions of chemical inactivation versus physical removal in achieving effective surface hygiene in the home environment.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003e2.1. Preparation of Environmental Microbial Suspension\u003cbr\u003e\u003c/strong\u003eTo simulate realistic environmental contamination, a complex microbial suspension was prepared from a soil source known to harbor a diverse microbiota but unlikely to contain significant levels of specific human pathogens. Fertile topsoil (pH 6.8, organic matter approx. 5%) was collected from a depth of 5-10 cm in an undisturbed, private garden location (Anytown, ON, Canada) that had not received recent pesticide or fertilizer treatment. Large debris (stones, roots) was manually removed. A suspension was created by thoroughly mixing 100 g of the sieved soil (\u0026lt;2 mm particle size) with 1000 mL of sterile 0.85% sodium chloride solution (saline) in a sterile 2 L Erlenmeyer flask. The mixture was agitated vigorously on an orbital shaker (Model OS-500, Advanced Scientific) at 150 rpm for 60 minutes at room temperature (approx. 22\u0026deg;C) to release soil-associated microbes into the liquid phase. The suspension was then allowed to stand undisturbed for 30 minutes to allow coarse particles to sediment. The supernatant, containing a rich suspension of environmental bacteria, fungi, and other microorganisms, was carefully decanted and filtered through four layers of sterile cheesecloth (Grade 50, Precision Textiles) into a sterile container to remove larger suspended particles while retaining the microbial load.\u003c/p\u003e\n\u003cp\u003eThis primary suspension was then standardized for use in contamination protocols. The optical density at 600 nm (OD600) was measured using a spectrophotometer (Model UV-1800, Shimadzu, Japan), although OD600 provides only a rough estimate for mixed environmental samples. More importantly, serial dilutions (10^-6, 10^-7, 10^-8) were prepared in sterile saline and plated in triplicate onto Plate Count Agar (PCA; BD Difco\u0026trade;, Becton, Dickinson and Company) using the spread plate technique (0.1 mL inoculum). Plates were incubated aerobically at 30\u0026deg;C for 72 hours. Based on preliminary trials, the primary suspension was diluted with sterile saline to achieve a target concentration of approximately 1 x 10^8 Colony Forming Units (CFU)/mL. This final working suspension was prepared fresh daily for contamination experiments to minimize population shifts. Aliquots were taken before each contamination batch for retrospective plating to confirm the consistency of the microbial load, which typically ranged from 0.8 x 10^8 to 1.5 x 10^8 CFU/mL throughout the study. The suspension was kept on ice during use but allowed to equilibrate to room temperature for 15 minutes immediately before surface contamination.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2. Surface Coupon Preparation\u003cbr\u003e\u003c/strong\u003eFour types of surfaces commonly found in households were selected for testing:\u003cbr\u003ea)\u0026nbsp;\u003cstrong\u003eCeramic Tile (CER):\u003c/strong\u003e Unglazed porcelain tiles (Manufacturer standard, TileWorks Inc.), characterized by slight surface roughness and moderate porosity.\u003cbr\u003eb)\u0026nbsp;\u003cstrong\u003eStainless Steel (SS):\u003c/strong\u003e Grade 304 stainless steel sheet (MetalSupplies Co.) with a standard No. 4 brushed finish, representing common kitchen appliance and countertop surfaces.\u003cbr\u003ec)\u0026nbsp;\u003cstrong\u003eHigh-Density Polyethylene (HDPE):\u003c/strong\u003e White HDPE sheet (PlasticsDirect), representing common cutting boards and food storage containers.\u003cbr\u003ed) \u003cstrong\u003eSealed Wood (WD):\u003c/strong\u003e Red Oak wood (FineWoods Ltd.) sealed with three coats of a clear, water-based polyurethane sealant (Varathane\u0026reg; Diamond Wood Finish, Rust-Oleum Canada), cured for 7 days, representing sealed furniture or flooring.\u003c/p\u003e\n\u003cp\u003eAll materials were cut into standardized coupons measuring 5.0 cm x 5.0 cm (surface area = 25 cm\u0026sup2;). Sharp edges were lightly smoothed to prevent injury and ensure uniform handling. Prior to each experiment, coupons were subjected to a rigorous cleaning and sterilization protocol to remove any manufacturing residues, environmental contaminants, or residual microbes from previous experiments (where applicable, though typically fresh coupons were used for each replicate run). The protocol involved:\u003c/p\u003e\n\u003col start=\"1\" type=\"1\"\u003e\n \u003cli\u003eWashing with a standard laboratory detergent (0.5% Liquinox\u0026reg;, Alconox, Inc.) using a soft brush.\u003c/li\u003e\n \u003cli\u003eThorough rinsing under running deionized water (DI water) for 2 minutes.\u003c/li\u003e\n \u003cli\u003eA final rinse with high-purity (Type I) DI water.\u003c/li\u003e\n \u003cli\u003eImmersion in 70% (v/v) isopropyl alcohol (IPA; Fisher Scientific Canada) for 10 minutes.\u003c/li\u003e\n \u003cli\u003eAseptic removal from IPA using sterile forceps, followed by air-drying in a Class II biological safety cabinet (BSC; Model 1300 Series A2, Thermo Fisher Scientific) for at least 60 minutes.\u003c/li\u003e\n \u003cli\u003eFor ceramic and stainless steel coupons, an additional step of autoclaving (121\u0026deg;C, 15 psi, 20 minutes) was performed, wrapped in aluminum foil. HDPE and sealed wood were not autoclaved due to potential material degradation; the 70% IPA treatment was considered sufficient for surface decontamination for these materials in this non-pathogen-focused study, confirmed by sterility control checks (swabbing un-inoculated, cleaned coupons showed \u0026lt;1 CFU/coupon).\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eSterilized coupons were stored in sterile containers (autoclaved glass Petri dishes or sterile bags) until use, typically within 24 hours of preparation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3. Surface Contamination Protocol\u003cbr\u003e\u003c/strong\u003eSterilized surface coupons were handled aseptically using sterile forceps within the BSC. Each coupon was fully immersed horizontally in the standardized environmental microbial suspension (approx. 1 x 10^8 CFU/mL, equilibrated to room temperature) in a sterile shallow tray for 60 \u0026plusmn; 2 seconds, ensuring complete wetting of the test surface. After immersion, each coupon was withdrawn vertically using sterile forceps, allowing excess suspension to drain off for 30 \u0026plusmn; 2 seconds against the side of the tray. The contaminated coupons were then placed flat, contaminated side up, inside sterile Petri dishes (150 mm diameter) lined with sterile filter paper to absorb minimal runoff without wicking moisture from the surface itself. The coupons were allowed to air-dry partially within the covered Petri dishes inside the BSC for 20 minutes at ambient temperature (22 \u0026plusmn; 1\u0026deg;C) and relative humidity (40-50%). This drying period aimed to mimic a more realistic scenario where contamination is not immediately wet when a cleaning/disinfection action occurs, allowing some degree of microbial attachment. Preliminary tests confirmed that this drying period did not cause excessive loss of viability but resulted in a consistently high initial microbial load on the surfaces.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.4. Treatment Agents and Application\u003cbr\u003e\u003c/strong\u003eA panel of test agents was prepared, encompassing commercial disinfectants, natural products, physical methods, and controls:\u003c/p\u003e\n\u003cul class=\"decimal_type\"\u003e\n \u003cli\u003e\u003cstrong\u003ePositive Controls:\u003c/strong\u003e\n \u003cul class=\"decimal_type\"\u003e\n \u003cli\u003e\u003cstrong\u003eSodium Hypochlorite (BLEACH):\u003c/strong\u003e Commercial household bleach containing 5.25% sodium hypochlorite (Clorox\u0026reg; Disinfecting Bleach) was diluted 1:10 (v/v) in sterile DI water immediately before use, yielding approx. 0.525% (5250 ppm) available chlorine.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eIsopropyl Alcohol (IPA):\u003c/strong\u003e 70% (v/v) solution prepared by diluting 99.9% IPA (Fisher Scientific Canada) with sterile DI water.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eCommercial Disinfectant:\u003c/strong\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eQuaternary Ammonium Compound (QAC):\u003c/strong\u003e A common commercial multi-surface disinfectant spray listing Alkyl dimethyl benzyl ammonium chloride (C12-C16) as the active ingredient (0.2% concentration stated on label.). Used undiluted as per manufacturer\u0026apos;s instructions.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eNatural Products / Household Substances:\u003c/strong\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eVinegar (VIN):\u003c/strong\u003e Standard commercial white distilled vinegar, verified by titration to contain 5.0 \u0026plusmn; 0.1% acetic acid (Heinz\u0026reg; Brand). Used undiluted.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eBaking Soda (BS):\u003c/strong\u003e Saturated solution prepared by adding excess Sodium Bicarbonate (NaHCO3; Arm \u0026amp; Hammer\u0026trade;, Church \u0026amp; Dwight Canada Corp.) to sterile DI water at room temperature, stirring vigorously for 15 minutes, and allowing undissolved solid to settle. The clear supernatant was decanted for use (approx. 9.6 g/100 mL or 9.6% w/v at 20\u0026deg;C).\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eTea Tree Oil (TTO):\u003c/strong\u003e 100% pure \u003cem\u003eMelaleuca alternifolia\u003c/em\u003e essential oil (Aura Cacia\u0026reg;, Available from Canadian Health Retailers). A 2.0% (v/v) emulsion was prepared by adding 2 mL TTO to 97.9 mL sterile DI water containing 0.1 mL Tween\u0026reg; 80 (Polysorbate 80; MilliporeSigma Canada) as an emulsifier, vortexed vigorously for 2 minutes before use.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eCleaning Agents / Physical Methods:\u003c/strong\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eAnionic Soap Scrub (SOAP):\u003c/strong\u003e A 1.0% (w/v) solution of a standard anionic bar soap (Ivory\u0026reg;, Procter \u0026amp; Gamble Canada, grated and dissolved in warm sterile DI water, then cooled). Applied via scrubbing.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eCold Water Scrub (CW):\u003c/strong\u003e Sterile DI water equilibrated to 15 \u0026plusmn; 1\u0026deg;C. Applied via scrubbing.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eHot Water Scrub (HW):\u003c/strong\u003e Sterile DI water heated to and maintained at 55 \u0026plusmn; 2\u0026deg;C. Applied via scrubbing.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eNegative Controls:\u003c/strong\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eSterile Water Wipe (SWW):\u003c/strong\u003e Sterile DI water at room temperature (22 \u0026plusmn; 1\u0026deg;C). Applied via wiping (minimal pressure, different from scrubbing).\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eNo Treatment (NT):\u003c/strong\u003e Contaminated coupons received no treatment and were processed immediately after the 20-minute drying period to establish the baseline microbial load.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eApplication Methods:\u003c/strong\u003e\u003c/p\u003e\n\u003cul class=\"decimal_type\"\u003e\n \u003cli\u003e\u003cstrong\u003eChemical Treatments (BLEACH, IPA, QAC, VIN, BS, TTO):\u003c/strong\u003e For these liquid treatments, two application methods were used depending on the product format and typical use:\u003cul class=\"decimal_type\"\u003e\n \u003cli\u003e\u003cstrong\u003eSpray:\u003c/strong\u003e QAC was applied using its integrated spray nozzle from a distance of 15-20 cm until the surface was thoroughly wet (approx. 1.5 - 2.0 mL per 25 cm\u0026sup2; coupon, standardized by practice).\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eWipe Application:\u003c/strong\u003e For BLEACH, IPA, VIN, BS, TTO, and the SWW control, sterile cotton gauze pads (4x4 inch / 10x10 cm, 8-ply, Life Brand\u0026trade;) were saturated with the respective test solution (approx. 5 mL per pad). The contaminated surface was wiped once with moderate, consistent pressure using the saturated pad, ensuring complete coverage. The pad was then discarded.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eContact Time:\u003c/strong\u003e After application (spraying or wiping), the treated coupons were left undisturbed in covered sterile Petri dishes for a standardized contact time of \u003cstrong\u003e5 minutes\u003c/strong\u003e at room temperature (22 \u0026plusmn; 1\u0026deg;C). This time was chosen as a realistic intermediate duration relevant to household practices.\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eScrubbing Treatments (SOAP, CW, HW):\u003c/strong\u003e For these treatments involving mechanical action, a standardized scrubbing protocol was employed. A sterile cotton gauze pad (as above) was saturated with the respective liquid (1% Soap, 15\u0026deg;C Water, 55\u0026deg;C Water; approx. 5 mL per pad). The contaminated coupon surface was scrubbed with moderate, consistent pressure (estimated at approx. 150-200 g force, standardized by operator training) for 10 full back-and-forth strokes covering the entire 25 cm\u0026sup2; area over a period of approximately 15 seconds. Immediately after scrubbing, the coupon was processed for microbial recovery (no additional contact time).\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003e2.5. Microbial Recovery and Neutralization\u003cbr\u003e\u003c/strong\u003eImmediately following the 5-minute contact time (for chemical treatments) or scrubbing action, residual disinfectant activity was neutralized, and surviving microorganisms were recovered from the coupon surfaces using a standardized swabbing technique validated according to ASTM E2315-16 principles (with modifications). The entire 25 cm\u0026sup2; surface area of each coupon was thoroughly swabbed using a sterile synthetic-tipped swab (HydraFlock\u0026reg;, Puritan Medical Products) pre-moistened with 1.0 mL of sterile Dey-Engley (D/E) Neutralizing Broth (BD Difco\u0026trade;). D/E broth contains multiple neutralizing agents (lecithin, polysorbate 80, sodium thiosulfate, sodium thioglycolate, sodium bisulfite) capable of inactivating a broad range of disinfectants, including QACs, halogens (bleach), alcohols, phenolics, and potentially components of essential oils. The swabbing pattern involved rigorous back-and-forth strokes covering the entire surface horizontally, then vertically, and finally diagonally (approximately 30 seconds total swabbing time).\u003c/p\u003e\n\u003cp\u003eImmediately after swabbing, the swab head was aseptically broken off into a sterile 15 mL centrifuge tube containing 4.0 mL of additional sterile D/E Neutralizing Broth, resulting in a total recovery volume of 5.0 mL. The tube was tightly capped and vortex mixed vigorously (Model VX-2500, VWR Canada) at maximum speed for 30 seconds to dislodge microbes from the swab matrix into the neutralizing broth. This constituted the primary microbial recovery sample (representing a 10^0 dilution relative to the recovery volume). Preliminary validation experiments using known concentrations of challenge organisms and representative disinfectants confirmed the efficacy of the D/E broth in neutralizing residual activity within this protocol (data not shown). Neutralizer toxicity controls also showed no significant inhibition of microbial growth from the environmental suspension.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.6. Culturing and Incubation\u003cbr\u003e\u003c/strong\u003eSerial tenfold dilutions (10^-1 to 10^-5, or further if needed based on expected efficacy) of the primary microbial recovery sample (in D/E broth) were prepared using sterile 0.85% saline as the diluent. From the appropriate dilutions (typically 10^-2, 10^-3, 10^-4 for treated samples, and 10^-4, 10^-5, 10^-6 for control samples), duplicate 0.1 mL aliquots were transferred onto the surface of pre-poured Plate Count Agar (PCA) plates (90 mm diameter, 15-20 mL agar volume). PCA was chosen as a general-purpose medium to support the growth of a wide range of common aerobic and facultative anaerobic environmental bacteria and, to some extent, yeasts and molds. The inocula were evenly spread over the agar surface using sterile disposable spreaders.\u003c/p\u003e\n\u003cp\u003ePlates were allowed to absorb the inoculum for approximately 15-20 minutes at room temperature before being inverted and placed into incubators. Incubation was carried out aerobically at \u003cstrong\u003e30\u0026deg;C \u0026plusmn; 1\u0026deg;C for 72 hours\u003c/strong\u003e. This temperature was selected as a compromise to facilitate growth of mesophilic environmental microbes without being overly selective, and the extended incubation time allowed for the recovery and visualization of slower-growing organisms present in the soil consortium.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.7. Colony Forming Unit (CFU) Enumeration and Log Reduction Calculation\u003cbr\u003e\u003c/strong\u003eFollowing the incubation period, plates were examined, and those exhibiting colony counts between 30 and 300 CFUs were selected for enumeration using a manual colony counter (Model SC6+, Stuart Scientific, UK - sourced via Canadian distributor) under appropriate magnification and illumination. The average CFU count from the duplicate plates of a countable dilution was recorded.\u003c/p\u003e\n\u003cp\u003eThe microbial load recovered from each coupon surface was calculated and expressed as CFU per square centimeter (CFU/cm\u0026sup2;). The calculation was performed as follows:\u003cbr\u003e\u0026nbsp;CFU/cm\u0026sup2; = (Average CFU count on selected plates \u0026times; Dilution Factor \u0026times; Total Recovery Volume [5 mL]) / (Volume Plated [0.1 mL] \u0026times; Surface Area [25 cm\u0026sup2;])\u003cbr\u003e\u0026nbsp;Where Dilution Factor is the reciprocal of the dilution plated (e.g., for 10^-3 dilution, Dilution Factor = 1000).\u003c/p\u003e\n\u003cp\u003eFor data analysis and comparison of efficacy, the CFU/cm\u0026sup2; values were log10 transformed. Plates showing fewer than 30 colonies at the lowest dilution plated (e.g., from the 0.1 mL of the 10^0 recovery sample) were considered to have counts below the limit of detection (LOD). The LOD for this method was calculated as: (1 CFU \u0026times; 1 \u0026times; 5 mL) / (0.1 mL x 25 cm\u0026sup2;) = 2 CFU/cm\u0026sup2;. For statistical purposes, samples yielding counts below the LOD were assigned a value of half the LOD (i.e., 1 CFU/cm\u0026sup2;, or 0 log10 CFU/cm\u0026sup2;). Plates with colonies too numerous to count (TNTC, \u0026gt;300 CFU) at the highest dilution plated necessitated re-plating from higher dilutions if available, or were excluded if re-plating was not possible (this occurred rarely due to appropriate dilution planning).\u003c/p\u003e\n\u003cp\u003eThe primary measure of antimicrobial efficacy for each treatment was the Log10 Reduction (LR) value, calculated relative to the mean log10 CFU/cm\u0026sup2; recovered from the corresponding No Treatment (NT) control group for that specific surface type and experimental run.\u003cbr\u003e\u0026nbsp;LR = Mean Log10 CFU/cm\u0026sup2; (NT Control) \u0026ndash; Log10 CFU/cm\u0026sup2; (Treated Sample)\u003cbr\u003e\u0026nbsp;A higher LR value indicates greater antimicrobial efficacy.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.8. Microbial Characterization (Gram Staining)\u003cbr\u003e\u003c/strong\u003eTo gain preliminary insight into the types of bacteria present in the initial inoculum and potentially surviving certain treatments, Gram staining was performed on selected samples. Smears were prepared from the standardized environmental suspension and from the recovery broths of NT controls and representative effective treatments (e.g., Bleach, Vinegar, TTO) for one surface type (Stainless Steel). Standard Gram staining procedure was followed (Crystal Violet - 1 min, Gram\u0026apos;s Iodine - 1 min, 95% Ethanol decolorization - 10-15 sec, Safranin counterstain - 1 min). Stained slides were examined under oil immersion (1000x magnification) using a light microscope (Model BX43, Olympus, Japan). Observations regarding Gram reaction (positive/negative), morphology (cocci, rods, filamentous), and relative abundance were recorded qualitatively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.9. Experimental Design and Replication\u003cbr\u003e\u003c/strong\u003eThe study employed a full factorial design investigating the effects of 11 treatments (including NT control) on 4 different surface types. For each unique combination of treatment and surface type, \u003cstrong\u003e12 independent replicate coupons\u003c/strong\u003e were processed (n=12). Replicates were typically conducted over several experimental days (e.g., 3-4 runs with 3-4 replicates per condition per run) to account for potential day-to-day variability. Within each run, treatments were randomized to minimize systematic bias. Appropriate controls (NT, SWW, BLEACH, IPA) were included in every experimental run. Sterility controls for media, diluents, surfaces, and neutralization procedures were also performed regularly.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.10. Statistical Analysis\u003cbr\u003e\u003c/strong\u003eAll statistical analyses were performed using R Statistical Software (v4.2.1, R Core Team, 2022). CFU/cm\u0026sup2; data were log10 transformed prior to analysis to stabilize variance and approximate normal distribution, which was assessed using Shapiro-Wilk tests and Q-Q plots.\u003c/p\u003e\n\u003cp\u003eDifferences in baseline contamination (log10 CFU/cm\u0026sup2;) across the four surface types (NT controls) were assessed using a one-way Analysis of Variance (ANOVA).\u003c/p\u003e\n\u003cp\u003eThe primary analysis involved comparing the Log10 Reduction (LR) values achieved by the different treatments. For each surface type separately, a one-way ANOVA was performed to determine if there were statistically significant differences in mean LR values among the treatment groups (excluding the NT control, as its LR is inherently zero). If the overall ANOVA was significant (p \u0026lt; 0.05), post-hoc pairwise comparisons were conducted using Tukey\u0026apos;s Honestly Significant Difference (HSD) test to identify which specific treatments differed significantly from each other.\u003c/p\u003e\n\u003cp\u003eTo assess the influence of surface type on the efficacy of each individual treatment agent, two-way ANOVA was considered, but due to expected interactions and differing baseline levels, we primarily focused on comparing the LR values for a specific agent across the four surface types using one-way ANOVA and Tukey\u0026apos;s HSD tests. For instance, the LR values for Vinegar were compared across Ceramic, Stainless Steel, HDPE, and Wood.\u003c/p\u003e\n\u003cp\u003ePairwise comparisons between specific treatments of interest (e.g., Hot Water Scrub vs. Cold Water Scrub, Vinegar vs. QAC) were also performed using Student\u0026apos;s t-tests (or Welch\u0026apos;s t-test if variances were unequal, assessed by Levene\u0026apos;s test) on the LR data, applying Bonferroni correction where multiple comparisons were made outside the main ANOVA framework.\u003c/p\u003e\n\u003cp\u003eA p-value of \u0026lt; 0.05 was considered statistically significant for all tests. Data are presented as mean \u0026plusmn; standard deviation (SD) for log10 CFU/cm\u0026sup2; and LR values.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.11. Safety Procedures\u003cbr\u003e\u003c/strong\u003eAll work involving microbial cultures was performed in a Class II Biological Safety Cabinet adhering to Biosafety Level 1 (BSL-1) practices, as the source material (soil) was not expected to contain known human pathogens and no pathogenic strains were intentionally cultured. Personal protective equipment (PPE), including laboratory coats, disposable gloves (changed frequently), and eye protection, was worn at all times. All contaminated materials (coupons, swabs, gauze pads, pipette tips, culture plates) were collected in biohazard bags and decontaminated by soaking in a 10% bleach solution (final concentration ~0.5% sodium hypochlorite) for at least 24 hours before disposal as regular waste, or by autoclaving where appropriate. Work surfaces were decontaminated with 70% IPA and/or 10% bleach solution before and after each experimental session.\u003c/p\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e3.1. Baseline Microbial Contamination and Control Performance\u003c/h2\u003e \u003cp\u003ePrior to applying any treatments, the standardized contamination protocol resulted in substantial and relatively consistent microbial loads on all four surface types, as determined from the No Treatment (NT) control coupons. The mean baseline contamination levels (log10 CFU/cm\u0026sup2; \u0026plusmn; SD, n\u0026thinsp;=\u0026thinsp;12 per surface type) were:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eCeramic Tile (CER): 6.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eStainless Steel (SS): 6.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eHDPE Plastic (HDPE): 6.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.24\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eSealed Wood (WD): 6.17\u0026thinsp;\u0026plusmn;\u0026thinsp;0.30\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eA one-way ANOVA indicated statistically significant differences in the initial microbial attachment among the surfaces (F(3, 44)\u0026thinsp;=\u0026thinsp;2.95, p\u0026thinsp;=\u0026thinsp;0.043), although these differences were small in magnitude. Post-hoc Tukey's HSD tests revealed that ceramic tiles harbored slightly higher initial counts compared to stainless steel (p\u0026thinsp;=\u0026thinsp;0.038), while other pairwise comparisons were not significant (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05). These baseline values provided the reference point for calculating Log Reduction (LR) for all treatments.\u003c/p\u003e \u003cp\u003eThe performance of the control treatments is summarized in Table\u0026nbsp;1 and Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The Sterile Water Wipe (SWW), representing minimal intervention with only moisture and light wiping, resulted in very low microbial reduction across all surfaces, with mean LR values ranging from 0.61 (Wood) to 0.88 (Stainless Steel). These minor reductions were statistically significant compared to zero reduction (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 for all surfaces, one-sample t-test against 0), but significantly less effective than all other active treatments (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, Tukey's HSD).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn contrast, the positive controls demonstrated high antimicrobial efficacy, validating the susceptibility of the environmental microbial consortium to standard disinfectants. The 1:10 dilution of 5.25% Sodium Hypochlorite (BLEACH) achieved the highest reductions on all surfaces, with mean LR values of 4.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.31 on Stainless Steel, 4.79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.35 on HDPE, 4.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40 on Ceramic, and 3.88\u0026thinsp;\u0026plusmn;\u0026thinsp;0.45 on Sealed Wood. 70% Isopropyl Alcohol (IPA) also showed strong efficacy, yielding mean LR values of 4.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.38 on Stainless Steel, 4.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.41 on HDPE, 3.95\u0026thinsp;\u0026plusmn;\u0026thinsp;0.42 on Ceramic, and 3.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.49 on Sealed Wood. For both BLEACH and IPA, the efficacy was significantly higher on the non-porous surfaces (SS, HDPE) compared to the more porous or textured surfaces (CER, WD) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, ANOVA comparing LR across surfaces for each agent).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e3.2. Efficacy of Commercial Disinfectant (QAC)\u003c/h2\u003e \u003cp\u003eThe commercial QAC-based disinfectant spray, used undiluted according to label instructions with a 5-minute contact time, demonstrated moderate antimicrobial efficacy that varied significantly depending on the surface material (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Table\u0026nbsp;2). The highest mean LR was observed on Stainless Steel (3.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.39), followed closely by HDPE (3.35\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44). Efficacy was significantly lower on Ceramic Tile (2.95\u0026thinsp;\u0026plusmn;\u0026thinsp;0.41) and Sealed Wood (2.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.48) (F(3, 44)\u0026thinsp;=\u0026thinsp;8.12, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 for effect of surface on QAC LR). On all surfaces, the QAC disinfectant was significantly more effective than the SWW control (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) but significantly less effective than both BLEACH and IPA positive controls (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, Tukey's HSD).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003e3.3. Efficacy of Natural Products and Household Substances\u003c/h2\u003e \u003cp\u003eThe performance of the tested natural products and common household substances showed considerable variation (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Table\u0026nbsp;2).\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eVinegar (VIN)\u003c/b\u003e: Undiluted white vinegar (5% acetic acid) exhibited substantial antimicrobial activity. It achieved mean LR values of 2.88\u0026thinsp;\u0026plusmn;\u0026thinsp;0.45 on Ceramic, 2.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.38 on Stainless Steel, 2.41\u0026thinsp;\u0026plusmn;\u0026thinsp;0.42 on HDPE, and 2.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.51 on Sealed Wood. Interestingly, vinegar's efficacy was highest on the ceramic surface and lowest on the sealed wood (F(3, 44)\u0026thinsp;=\u0026thinsp;6.55, p\u0026thinsp;=\u0026thinsp;0.001 for effect of surface on VIN LR). Notably, on Ceramic Tile, the LR achieved by vinegar was statistically indistinguishable from that of the commercial QAC disinfectant (p\u0026thinsp;=\u0026thinsp;0.88, Tukey's HSD). On Stainless Steel and HDPE, vinegar was significantly less effective than QAC (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), while on Sealed Wood, the difference approached but did not reach significance (p\u0026thinsp;=\u0026thinsp;0.06). Vinegar was significantly more effective than the SWW control on all surfaces (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eBaking Soda (BS)\u003c/b\u003e: The saturated solution of sodium bicarbonate demonstrated very limited antimicrobial activity under these test conditions. Mean LR values were consistently low across all surfaces: 0.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.22 (Ceramic), 0.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25 (Stainless Steel), 0.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20 (HDPE), and 0.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.28 (Sealed Wood). These reductions were only slightly better than the SWW control, and the difference was not statistically significant on HDPE and Wood (p\u0026thinsp;\u0026gt;\u0026thinsp;0.1). Compared to all other active chemical treatments (including vinegar), baking soda was significantly less effective (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eTea Tree Oil (TTO)\u003c/b\u003e: The 2% emulsion of \u003cem\u003eMelaleuca alternifolia\u003c/em\u003e oil showed strong but somewhat variable antimicrobial efficacy. It achieved high mean LR values, particularly on HDPE (3.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55) and Stainless Steel (3.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.51). Its performance was slightly lower on Ceramic (2.99\u0026thinsp;\u0026plusmn;\u0026thinsp;0.48) and Sealed Wood (2.45\u0026thinsp;\u0026plusmn;\u0026thinsp;0.60). The effect of surface type on TTO efficacy was significant (F(3, 44)\u0026thinsp;=\u0026thinsp;9.15, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). TTO efficacy was statistically comparable to the commercial QAC on HDPE (p\u0026thinsp;=\u0026thinsp;0.45) and Ceramic (p\u0026thinsp;=\u0026thinsp;0.99), slightly lower than QAC on Stainless Steel (p\u0026thinsp;=\u0026thinsp;0.04), and potentially lower on Wood (p\u0026thinsp;=\u0026thinsp;0.07). Compared to vinegar, TTO showed significantly higher LR values on SS and HDPE (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01) but similar efficacy on Ceramic (p\u0026thinsp;=\u0026thinsp;0.75) and Wood (p\u0026thinsp;=\u0026thinsp;0.18). The standard deviations for TTO results were generally larger compared to other agents like vinegar or QAC, suggesting greater variability in its action or potentially in the emulsion stability/application. TTO was significantly more effective than SWW and Baking Soda controls on all surfaces (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003e3.4. Efficacy of Physical Cleaning Methods (Scrubbing with Water and Soap)\u003c/h2\u003e \u003cp\u003eThe treatments involving standardized mechanical scrubbing action demonstrated notable efficacy in reducing microbial load, highlighting the importance of physical removal (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Table\u0026nbsp;2).\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eCold Water Scrub (CW)\u003c/b\u003e: Scrubbing with sterile DI water at ~\u0026thinsp;15\u0026deg;C achieved mean LR values ranging from 1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29 (Wood) to 1.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.33 (Stainless Steel). This represented a significant improvement over the passive Sterile Water Wipe (SWW) on all surfaces (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), demonstrating the added benefit of mechanical action alone.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eHot Water Scrub (HW)\u003c/b\u003e: Using hot water (~\u0026thinsp;55\u0026deg;C) for scrubbing resulted in significantly higher microbial reductions compared to cold water scrubbing on all four surface types (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01 for all pairwise comparisons, t-tests). Mean LR values for HW scrubbing ranged from 1.81\u0026thinsp;\u0026plusmn;\u0026thinsp;0.35 (Wood) to 2.38\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40 (Stainless Steel). The improvement over cold water scrubbing suggests an additional benefit from the elevated temperature, either through enhanced physical removal (e.g., loosening microbial attachment or soil) or potentially some degree of thermal inactivation of more sensitive microbes, even with the short contact time during scrubbing.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eSoap Scrub (SOAP)\u003c/b\u003e: Scrubbing with a 1% anionic soap solution yielded efficacy comparable to, or slightly better than, hot water scrubbing. Mean LR values ranged from 1.92\u0026thinsp;\u0026plusmn;\u0026thinsp;0.38 (Wood) to 2.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.45 (Stainless Steel). Soap scrubbing was significantly more effective than cold water scrubbing on all surfaces (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Compared to hot water scrubbing, soap scrubbing showed a statistically significant advantage on Stainless Steel (p\u0026thinsp;=\u0026thinsp;0.04) and HDPE (p\u0026thinsp;=\u0026thinsp;0.03), but not on Ceramic (p\u0026thinsp;=\u0026thinsp;0.25) or Wood (p\u0026thinsp;=\u0026thinsp;0.55). This suggests that the surfactant properties of soap, combined with mechanical action, provide a robust method for microbial removal.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eComparing the scrubbing methods to the chemical agents, hot water scrubbing and soap scrubbing achieved LR values that were significantly higher than those of baking soda (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and generally comparable to or slightly lower than those achieved by vinegar (5% acetic acid), depending on the surface. For instance, on Stainless Steel, the LR for HW scrub (2.38) and Soap scrub (2.65) were similar to vinegar (2.55). However, scrubbing methods were generally less effective than the QAC disinfectant, TTO emulsion, and the positive controls (IPA, Bleach) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 in most cases, Tukey's HSD).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003e3.5. Influence of Surface Type on Efficacy\u003c/h2\u003e \u003cp\u003eAs indicated in the results for individual agents and methods, surface material had a significant impact on the measured antimicrobial efficacy for most treatments (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, ANOVA comparing LR across surfaces for each agent, except for Baking Soda where the effect was marginal, p\u0026thinsp;=\u0026thinsp;0.06). Generally, higher LR values were achieved on the smooth, non-porous surfaces (Stainless Steel and HDPE) compared to the more porous or textured surfaces (Ceramic Tile and Sealed Wood). This effect was most pronounced for the highly effective chemical disinfectants (Bleach, IPA) where LR differences between non-porous and porous surfaces often exceeded 0.5 log10. For agents like QAC, TTO, and Vinegar, the pattern was similar but sometimes less consistent (e.g., Vinegar performed best on Ceramic). Scrubbing methods (CW, HW, SOAP) also generally showed higher LR on SS and HDPE compared to Ceramic and Wood, suggesting physical removal might also be less efficient on rougher or more porous materials. Sealed wood consistently presented the greatest challenge for nearly all treatments, yielding the lowest LR values in most cases.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec20\" class=\"Section2\"\u003e \u003ch2\u003e3.6. Qualitative Microbial Characterization (Gram Stain)\u003c/h2\u003e \u003cp\u003eGram staining of the initial environmental microbial suspension revealed a highly diverse population dominated by Gram-negative rods of various morphologies, along with smaller proportions of Gram-positive rods (some spore-forming types observed) and Gram-positive cocci. Fungal elements (yeast-like cells, hyphal fragments) were also occasionally observed but were less numerous than bacteria under these viewing conditions.\u003c/p\u003e \u003cp\u003ePreliminary examination of smears from recovery broths after treatment on Stainless Steel suggested potential differential effects. The highly effective treatments (Bleach, IPA) resulted in very few observable cells, as expected. After treatment with Vinegar and TTO, the relative proportion of observable Gram-positive bacteria (particularly cocci and some rods) appeared slightly increased compared to the Gram-negative rods seen in the NT control, hinting at potentially greater susceptibility of the Gram-negative bacteria typically dominant in the soil suspension to these agents. However, these observations were qualitative and require more rigorous quantitative culture-based or molecular methods for confirmation. No obvious morphological changes were noted in the surviving cells.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cdiv id=\"Sec22\" class=\"Section2\"\u003e \u003ch2\u003e4.1. Interpretation of Key Findings: Unveiling the Nuances of Household Hygiene\u003c/h2\u003e \u003cp\u003eThe substantial baseline contamination achieved (~\u0026thinsp;6.1 log10 CFU/cm\u0026sup2;) validates the model's ability to represent a significant microbial challenge, enabling robust quantification of log reductions. As expected, 0.5% sodium hypochlorite (Bleach) and 70% IPA delivered superior broad-spectrum efficacy (LR\u0026thinsp;\u0026gt;\u0026thinsp;3.5 - \u0026gt; 4.8), consistent with their established roles as potent disinfectants [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Their diminished performance on porous/textured surfaces (Ceramic, Wood) versus non-porous (SS, HDPE) underscores the critical limitation imposed by surface characteristics \u0026ndash; likely due to incomplete penetration, agent absorption/neutralization, and physical protection of microbes within surface irregularities [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eStrikingly, the widely used commercial QAC disinfectant demonstrated only moderate efficacy (LR 2.8\u0026ndash;3.5) under these realistic conditions (5 min contact time), significantly underperforming compared to bleach and IPA. This finding is particularly relevant given QACs' known limitations against Gram-negative bacteria (dominant in our soil inoculum) and susceptibility to environmental factors [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. The observed performance variability across surfaces, with higher efficacy on SS and HDPE, further highlights that QAC effectiveness is strongly context-dependent.\u003c/p\u003e \u003cp\u003ePerhaps one of the most significant findings for household practice is the substantial efficacy of 5% acetic acid (vinegar). Achieving LR values of 2.1\u0026ndash;2.9, vinegar proved remarkably effective against this complex environmental consortium. Critically, its performance was statistically comparable to the commercial QAC disinfectant on ceramic tile and approached QAC efficacy on sealed wood. This provides strong quantitative evidence supporting the utility of vinegar as a readily available, inexpensive, and less harsh alternative for meaningful microbial reduction on certain surfaces, aligning with but significantly strengthening previous reports often focused on specific pathogens [\u003cspan additionalcitationids=\"CR35\" citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. The intriguing observation of peak vinegar performance on ceramic warrants further study into surface-agent interactions.\u003c/p\u003e \u003cp\u003eThe 2% Tea Tree Oil emulsion also displayed potent antimicrobial activity (LR 2.5\u0026ndash;3.6), especially on non-porous surfaces (HDPE, SS), rivaling QAC efficacy on HDPE and Ceramic. This confirms TTO's potential as a natural antimicrobial, likely driven by membrane-active compounds like terpinen-4-ol [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. However, the larger variability (SDs) and need for emulsification (Tween 80 used here) are practical considerations for its consistent application.\u003c/p\u003e \u003cp\u003eIn stark contrast, and potentially dispelling common assumptions, saturated sodium bicarbonate (baking soda) demonstrated negligible antimicrobial activity (LR\u0026thinsp;\u0026lt;\u0026thinsp;0.8), barely exceeding the minimal removal from a simple water wipe. This quantitatively confirms that baking soda, while useful for cleaning or deodorizing, should not be relied upon for microbial reduction in household hygiene protocols [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eCrucially, this study highlights the underappreciated significance of physical removal through scrubbing. Simple cold water scrubbing (LR 1.3\u0026ndash;1.9) was substantially more effective than passive wiping. Elevating the temperature to 55\u0026deg;C (Hot Water Scrub, LR 1.8\u0026ndash;2.4) provided a statistically significant additional benefit, likely enhancing physical detachment or affecting sensitive microbes even during brief contact [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Incorporating 1% anionic soap (Soap Scrub, LR 1.9\u0026ndash;2.7) further boosted efficacy, particularly on non-porous surfaces, demonstrating the combined power of mechanical force and surfactant action in physically lifting and removing microbes [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]. Remarkably, the log reductions achieved by hot water or soap scrubbing were often comparable to, or even exceeded, those of 5% vinegar on several surfaces, emphasizing that rigorous mechanical cleaning is a cornerstone of effective surface hygiene, capable of rivaling some chemical interventions.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec23\" class=\"Section2\"\u003e \u003ch2\u003e4.2. Impact of Surface Characteristics: A Critical Determinant of Efficacy\u003c/h2\u003e \u003cp\u003eA consistent and critical theme emerging from this research is the profound influence of surface material. The general hierarchy of efficacy \u0026ndash; highest on smooth, non-porous SS and HDPE, lowest on porous/textured ceramic and particularly sealed wood \u0026ndash; held true for nearly all treatments, chemical and physical alike. This finding carries immense practical weight: disinfection expectations and strategies must account for surface properties. Microbes find sanctuary in microscopic topography, shielding them from chemicals and mechanical removal [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. Sealed wood consistently posed the greatest decontamination challenge, likely reflecting residual micro-porosity, texture, potential chemical interactions, and strong microbial adhesion even after sealing [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]. This underscores the need for potentially longer contact times or more rigorous methods on such challenging materials.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec24\" class=\"Section2\"\u003e \u003ch2\u003e4.3. Comparison with Existing Literature: Providing Unique Quantitative Benchmarks\u003c/h2\u003e \u003cp\u003eWhile our findings broadly align with the established disinfectant hierarchy (Bleach/Alcohol\u0026thinsp;\u0026gt;\u0026thinsp;QACs), this study's unique contribution lies in providing novel, direct quantitative comparisons across an unprecedented range of common household practices (commercial, natural, physical) tested side-by-side against a complex environmental microbial load on multiple representative surfaces. Previous work often lacked this breadth, focusing on fewer variables [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan additionalcitationids=\"CR44\" citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. The robust evidence for vinegar's efficacy and, critically, the quantified contribution of simple scrubbing with water or soap [\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e, \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e], benchmarked against chemical agents in the same system, provides data essential for evidence-based hygiene messaging that often overemphasizes chemical disinfection. The confirmation of TTO's potential, alongside practical considerations like emulsification and potential sensitization [\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e], adds valuable context for \"natural\" product evaluation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec25\" class=\"Section2\"\u003e \u003ch2\u003e4.4. Strengths and Limitations\u003c/h2\u003e \u003cp\u003eThe key strengths lie in the rigorous standardization across multiple variables (surfaces, complex inoculum, application, recovery, n\u0026thinsp;=\u0026thinsp;12 replication), the breadth of relevant treatments compared, and the use of validated neutralization, allowing for robust conclusions about relative efficacy under the tested conditions.\u003c/p\u003e \u003cp\u003eHowever, limitations must be acknowledged. The single-source soil consortium, while diverse, may not fully represent all home environments [49, 50]. We focused on culturable aerobic/facultative mesophiles on PCA, excluding viruses, anaerobes, specific pathogens, and VBNC states. The 20-minute drying time represents initial attachment, not mature biofilms or heavy soil loads, which could significantly impede disinfectant action [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. The single 5-minute contact time for chemicals may not reflect optimal or minimal use conditions. Manual scrubbing introduces potential operator variability despite standardization efforts. Sealed wood properties can vary, and unsealed wood would present an even greater challenge. Finally, Gram stain observations are preliminary indicators of differential susceptibility requiring confirmation.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec26\" class=\"Section2\"\u003e \u003ch2\u003e4.5. Implications and Future Directions: Towards Evidence-Based Household Hygiene\u003c/h2\u003e \u003cp\u003eDespite limitations, these findings possess significant practical implications, offering quantitative, actionable intelligence for consumers and public health professionals navigating household hygiene choices. The study strongly suggests:\u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eBleach and alcohol remain the most potent disinfectants tested, appropriate for high-risk situations requiring maximal kill.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eCommon QAC disinfectants offer moderate, surface-dependent efficacy against environmental microbes, performing less effectively than bleach/alcohol in this model.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eVinegar (5% acetic acid) emerges as a surprisingly effective, readily available, inexpensive alternative, offering substantial microbial reduction, particularly on surfaces like ceramic tile, potentially rivaling QACs without associated harshness or resistance concerns.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eTea Tree Oil (2%) shows significant promise as a natural antimicrobial, but requires careful formulation and consideration of variability/sensitization.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eBaking soda is largely ineffective for microbial reduction.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003ePhysical scrubbing is profoundly important. Using hot water or simple soap significantly enhances microbial removal, achieving efficacy levels that can approach or match moderate chemical agents like vinegar, forming the foundation of routine hygiene.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003c/p\u003e \u003cp\u003eThese results powerfully advocate for a multifaceted approach to household hygiene. Routine cleaning should prioritize thorough mechanical action (scrubbing) with basic agents like soap and water. Chemical disinfection, whether using commercial products or effective natural alternatives like vinegar, can then be targeted based on the specific situation (e.g., contamination event, high-risk area), surface type (considering porous vs. non-porous), and the desired level of microbial reduction. This evidence empowers informed choices, potentially reducing reliance on harsher chemicals where simpler, effective alternatives exist.\u003c/p\u003e \u003cp\u003eFuture research should build upon this foundational work by: evaluating diverse environmental consortia (kitchen, bathroom); including specific pathogens and viruses; testing against mature biofilms and standardized soil loads; investigating varying contact times/concentrations; exploring additional surfaces (laminate, glass, textiles); employing molecular methods (e.g., 16S rRNA sequencing) for deeper insights into community shifts and differential susceptibility; assessing potential resistance development (especially for QACs/TTO); and investigating synergistic effects (e.g., vinegar followed by scrubbing).\u003c/p\u003e \u003c/div\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eThis study provides a unique and rigorous quantitative comparison of the antimicrobial efficacy of diverse household substances and practices against environmental microbes on common surfaces. It delivers crucial evidence demonstrating that while 0.5% sodium hypochlorite and 70% isopropyl alcohol offer superior disinfection, commonly available 5% acetic acid (vinegar) and 2% tea tree oil emulsion exhibit substantial antimicrobial activity, sometimes comparable to commercial QAC disinfectants. Critically, the study quantifies the significant contribution of the physical act of scrubbing, particularly with hot water or soap, revealing its efficacy can rival that of some chemical treatments, while conversely showing saturated baking soda offers negligible benefit. Efficacy was profoundly impacted by surface type, emphasizing the need for tailored approaches. These findings challenge over-reliance on chemical disinfection alone, underscore the fundamental importance of mechanical removal, and provide robust, evidence-based insights. They empower the selection and application of cleaning and disinfection methods \u0026ndash; including effective, less harsh, readily available options alongside traditional physical cleaning \u0026ndash; enabling a more informed, multifaceted, and potentially safer approach to achieving effective surface hygiene in the home.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author wishes to express sincere gratitude to Dr. Raymond Yang for generously providing access to the necessary laboratory facilities, equipment, and resources which made this study possible\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJ.T. is the sole author and was responsible for all aspects of this work, including conceptualization, methodology design, investigation (experimental execution), data acquisition and curation, formal analysis, validation, visualization, project administration, and writing the original draft, review, and editing of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003cbr\u003e\u003c/strong\u003eThe datasets generated and analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003cbr\u003e\u003c/strong\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. 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Indoor airborne bacterial communities are influenced by ventilation, occupancy, and outdoor air source. \u003cem\u003eIndoor Air\u003c/em\u003e. \u003cb\u003e24\u003c/b\u003e (1), 41\u0026ndash;48 (2014).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 and 2 are available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6448022/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6448022/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eBackground\u003c/b\u003e\u003c/p\u003e \u003cp\u003eSurface contamination by environmental microbes presents domestic hygiene challenges. While commercial disinfectants are common, interest grows in household substances (vinegar, tea tree oil) and physical methods, but standardized comparative data against realistic microbial consortia on diverse surfaces remain scarce.\u003c/p\u003e\u003cp\u003e\u003cb\u003eObjective\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTo quantitatively compare antimicrobial efficacy of commercial disinfectants (QAC, bleach, alcohol), household agents (vinegar, baking soda, tea tree oil), physical/soap scrubbing against a mixed environmental soil microbial consortium on four common household surfaces (ceramic, stainless steel, HDPE, sealed wood) via a standardized laboratory model.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eStandardized coupons (4 surfaces) were contaminated (~\u0026thinsp;10^8 CFU/mL soil suspension). Treatments included commercial (0.2% QAC, 0.5% hypochlorite, 70% IPA), household (5% vinegar, saturated baking soda, 2% tea tree oil), physical/soap scrubbing, and controls. After 5-min contact (chemicals), microbes were recovered via swabbing into neutralizer and quantified (aerobic plate counts). Efficacy\u0026thinsp;=\u0026thinsp;Log10 Reduction (LR) vs controls (n\u0026thinsp;=\u0026thinsp;12/condition). ANOVA/Tukey's (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) used.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eBaseline was ~\u0026thinsp;6.1 log10 CFU/cm\u0026sup2;. Bleach (LR\u0026thinsp;\u0026gt;\u0026thinsp;3.8) and IPA (LR\u0026thinsp;\u0026gt;\u0026thinsp;3.5) showed highest efficacy; commercial QAC was moderate (LR 2.8\u0026ndash;3.5), varying by surface. 5% Vinegar (LR 2.1\u0026ndash;2.9) and 2% Tea Tree Oil (LR 2.5\u0026ndash;3.6) demonstrated substantial activity, sometimes comparable to QAC. Baking soda had minimal effect (LR\u0026thinsp;\u0026lt;\u0026thinsp;0.8). Hot water (LR 1.8\u0026ndash;2.4) and soap scrubbing (LR 1.9\u0026ndash;2.7) significantly outperformed cold water scrubbing (LR 1.3\u0026ndash;1.9). Efficacy was generally lower on porous/textured surfaces (ceramic, wood).\u003c/p\u003e","manuscriptTitle":"Quantitative Benchmarking of Household Surface Decontamination: Comparing Chemical Disinfectants, Natural Alternatives, and Physical Removal of Environmental Microbes","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-30 12:55:49","doi":"10.21203/rs.3.rs-6448022/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"60a8e0fe-3ba7-4515-8007-74c8d7968997","owner":[],"postedDate":"April 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":47842196,"name":"Biological sciences/Microbiology"},{"id":47842197,"name":"Earth and environmental sciences/Environmental sciences"},{"id":47842198,"name":"Health sciences/Diseases"},{"id":47842199,"name":"Health sciences/Health care"},{"id":47842200,"name":"Health sciences/Risk factors"},{"id":47842201,"name":"Physical sciences/Materials science"}],"tags":[],"updatedAt":"2025-06-30T06:08:40+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-30 12:55:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6448022","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6448022","identity":"rs-6448022","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}