Antimicrobial Resistance Spread Through Medical Waste: Environmental Contamination and Public Health Implications in Urban Nigeria

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This study examines the relationship between inadequate medical waste management and AMR propagation in Lagos, Nigeria's megacity of over 20 million inhabitants. Through mixed-methods assessment of seven healthcare facilities, we documented significant deficiencies: only 61% proper waste segregation at source, 33.3% correct identification of pharmaceutical waste protocols, storage durations of 5–10 days (versus recommended 24–48 hours), and widespread mixing of antimicrobial-containing waste with general streams. Facilities generated 215.56 kg/day of medical waste (0.181 kg/bed/day average), with pharmaceutical waste comprising 5–8% yet receiving no specialized treatment beyond standard hydroclave sterilization - inadequate for degrading antimicrobial compounds. Analysis reveals multiple environmental contamination pathways: wastewater discharge, storage site leachate, transport spillage, and inadequate final disposal exposing waste handlers, communities, and environmental matrices to antimicrobial residues and resistant bacteria. Nigeria's fragmented policy framework, characterized by weak enforcement and absent AMR-specific provisions, exacerbates these challenges. Cost constraints, limited technical capacity, and insufficient training emerged as primary implementation barriers. This study proposes an integrated framework combining enhanced segregation, AMR-targeted treatment technologies, environmental monitoring, strengthened regulatory enforcement with AMR provisions, and community-based approaches. Findings have significant implications for public health policy in resource-constrained urban settings where inadequate waste infrastructure creates conditions for AMR amplification and dissemination through environmental pathways. antimicrobial resistance medical waste management environmental contamination public health Lagos Nigeria pharmaceutical waste healthcare facilities 1. Introduction 1.1 Background and Significance Antimicrobial resistance threatens to cause 10 million deaths annually by 2050 if current trends continue (World Health Organization, 2021). While clinical antimicrobial use receives considerable attention as an AMR driver, environmental contamination through inadequate medical waste management remains critically underexamined, particularly in low- and middle-income countries with deficient waste infrastructure (Khan et al., 2019). Healthcare facilities generate substantial waste containing antimicrobial residues, resistant bacteria, and mobile genetic elements - materials that, when improperly managed, contribute significantly to AMR dissemination in environmental compartments (Singh et al., 2021). Nigeria exemplifies the convergence of factors amplifying AMR risks through medical waste pathways. The country's healthcare system generates over 500,000 tons of medical waste annually yet lacks comprehensive treatment and disposal infrastructure (Ezeudu et al., 2022). Lagos State, with 20+ million inhabitants and serving as Nigeria's commercial center, faces particularly acute challenges as concentrated healthcare facilities, rapid urbanization, and inadequate waste management systems create conditions conducive to AMR propagation (Olukanni et al., 2022). The medical waste-AMR nexus operates through multiple mechanisms: pharmaceutical waste containing active antimicrobial compounds creates selective pressure for resistance development in environmental bacteria (Navarro & Vincenzo, 2019); infectious waste from antimicrobial-treated patients harbors resistant bacteria capable of horizontal gene transfer to environmental microorganisms (Das et al., 2021); contaminated sharps and laboratory waste serve as transmission vectors to waste handlers and communities (Chisholm et al., 2021); and inadequate treatment facilities fail to inactivate antimicrobial compounds and resistant bacteria before disposal, allowing environmental persistence (Sangkham, 2020). 1.2 Research Gap and Objectives While existing literature documents medical waste management deficiencies in developing countries, the specific linkage between these practices and AMR propagation remains inadequately explored. Most studies address waste management or AMR in isolation, without examining mechanistic connections and environmental pathways through which inadequate waste practices contribute to resistance dissemination (Khan et al., 2019). This study addresses this gap by systematically examining medical waste management in Lagos healthcare facilities through an AMR lens, documenting environmental contamination pathways, and proposing integrated interventions. Objectives: Assess current medical waste management practices with specific attention to antimicrobial-containing materials Identify environmental contamination pathways facilitating AMR dissemination Evaluate policy and institutional frameworks governing medical waste management and their adequacy for addressing AMR risks Develop evidence-based recommendations integrating AMR considerations into waste management policies and practices 2. Literature Review 2.1 AMR and Environmental Dimensions Antimicrobial resistance has evolved from clinical curiosity to global health emergency, with environmental compartments serving as critical reservoirs and transmission pathways for resistance genes and resistant bacteria (Khan et al., 2021). Healthcare facilities contribute significantly through wastewater discharge, pharmaceutical waste disposal, and inadequate infectious waste treatment (Hassan et al., 2021). These environmental reservoirs facilitate horizontal gene transfer between bacterial species, creating opportunities for resistance dissemination beyond original hosts (Njoku et al., 2019). 2.2 Medical Waste as AMR Vector Medical waste represents a particularly concerning AMR vector due to concentrated antimicrobial agents, resistant microorganisms, and conducive environmental conditions throughout the waste management chain (Hantoko et al., 2021). Infectious waste from antimicrobial-treated patients contains resistant bacteria; pharmaceutical waste includes active antimicrobials maintaining selective pressure; laboratory waste harbors cultured resistant organisms; and sharps contaminated with blood from treated patients serve as direct transmission vectors (Olaniyi et al., 2019). Mechanisms operate at multiple scales: antimicrobial compounds in pharmaceutical waste exert selective pressure on environmental bacterial populations (Andeobu et al., 2022); waste disposal sites create microenvironments with elevated bacterial density and stress conditions enhancing horizontal gene transfer (Chisholm et al., 2021); waste handlers, scavengers, and communities experience direct exposure through occupational contact and environmental contamination (Ezeudu et al., 2022). 2.3 Medical Waste Management in Developing Countries Studies across Asia, Africa, and Latin America document common deficiencies: inadequate segregation mixing infectious and pharmaceutical wastes with general waste (Khan et al., 2019); insufficient treatment infrastructure (Ferronato & Vincenzo, 2019); prolonged storage exceeding recommended timeframes (Olaniyi et al., 2019); unsafe transport exposing waste handlers (Padmanabhan & Barik, 2019); and inadequate final disposal with untreated medical waste in open dumps (Singh et al., 2021). These deficiencies reflect broader constraints: insufficient funding, limited technical capacity, weak regulatory enforcement, rapid healthcare expansion without corresponding waste planning, and competing priorities (Chisholm et al., 2021). 2.4 The Nigerian Context Nigeria's policy framework includes the National Policy on Injection Safety and Healthcare Waste Management (2007) and National Healthcare Waste Management Plan, but implementation remains inconsistent (Ezirim & Agbo, 2018). Lagos has developed more robust infrastructure than most Nigerian regions, including the Lagos Waste Management Authority (LAWMA) medical waste unit, hydroclave treatment facilities, and private sector participation (Adetola, 2023). Despite these advances, studies document persistent deficiencies: inadequate segregation, treatment capacity constraints, prolonged storage, and limited verification of disposal practices (Olukanni et al., 2022). Pharmaceutical waste handling receives insufficient attention in protocols and practices (Awodele et al., 2016). 2.5 Environmental AMR Pathways Pathways through which inadequate treatment of medical waste contributes to environmental AMR include: wastewater discharge carrying antimicrobial residues and resistant bacteria (Khan et al., 2021); leachate from disposal sites contaminating groundwater and surface water (Siddiqua et al., 2022); aerosol generation during incineration dispersing resistant bacteria (Khalid et al., 2021); soil contamination creating resistance gene reservoirs (Marfe & Stefano, 2020); and direct exposure of waste handlers and communities (Cook & Velis, 2021). 2.6 Theoretical Framework This research adopts an integrated socio-ecological framework recognizing AMR dissemination through medical waste as a complex system involving interactions across individual (healthcare worker practices), facility (infrastructure, management), policy (regulations, enforcement), community (exposure pathways), and environmental (AMR reservoirs) levels (Corvalan et al., 2020). The framework incorporates environmental justice perspectives recognizing vulnerable populations bear disproportionate risks (Pulido, 2017) and political economy perspectives situating challenges within broader structural inequalities (Sibanda, 2019). 3. Methodology 3.1 Study Design and Setting This concurrent mixed-methods study combined quantitative assessments with qualitative exploration of stakeholder perspectives, policy frameworks, and contamination pathways (Harrison et al., 2020). Conducted October 2021 - March 2022 in Lagos State's Alimosho and Mushin Local Government Areas, the study selected Lagos due to its status as Nigeria's largest city, concentration of healthcare facilities (25% of country's private sector), relatively advanced waste infrastructure, and availability of comparative data (Olukanni et al., 2022). 3.2 Sample Selection and Size Healthcare facilities were selected using stratified purposive sampling across public tertiary, public secondary, public primary, and private facilities. Final sample comprised seven facilities: one federal teaching hospital (Facility A, 450 beds), one state general hospital (Facility B, 180 beds), two primary health centers (Facilities C and D, 15-20 beds each), and three private hospitals (Facilities E, F, G, 30-50 beds each). For quantitative components, Cochran's formula [n = (ZÇpq)/EÇ] with Z=1.96, p=0.5, E=0.05 yielded required sample size of 384. From 400 distributed questionnaires, 336 were completed (87.5% response rate). Qualitative sampling engaged key stakeholders: facility administrators (n=7), infection control officers (n=7), nurses (n=12), laboratory personnel (n=8), cleaners (n=10), LAWMA officials (n=3), and private operators (n=2), continuing until thematic saturation (Renjith et al., 2021). 3.3 Data Collection Methods Facility Assessment: Structured assessments documented waste generation rates and composition, segregation practices, storage infrastructure and duration, treatment capabilities, transport arrangements, disposal verification, and staff training. Each facility received 3-5 visits over the study period. Questionnaire Survey: Structured questionnaires administered to healthcare workers comprised six sections: demographics (10 items), waste categorization knowledge with AMR-specific items (15 items), segregation practices (12 items), storage and transport (8 items), training (6 items), and AMR-waste linkages awareness (10 items). Pilot testing with 20 workers refined the instrument. Semi-Structured Interviews: In-depth interviews with key informants explored current practices, pharmaceutical/antimicrobial waste handling, AMR-waste awareness, policy frameworks, constraints, and improvement recommendations. Interviews lasted 30-75 minutes; with consent, were audio-recorded and transcribed verbatim. Observational Data: Systematic observation documented practices at waste generation points, collection points, during transport, at transfer stations, and treatment/disposal facilities (where access permitted). Document Review: Analysis of national policies, facility records, regulatory documents, and international guidelines provided contextual understanding and identified policy-practice gaps. 3.4 Data Analysis Quantitative: SPSS version 26 analyzed questionnaire and facility data using descriptive statistics and chi-square tests examining associations between variables (significance p<0.05). Qualitative: Thematic analysis following Braun and Clarke's framework coded interviews, observations, and documents using NVivo 12. Codebook developed iteratively organized codes into thematic categories. Inter-coder reliability (Cohen's Kappa=0.82) confirmed substantial agreement (Jones & Donmoyer, 2021). Integration: Mixed-methods integration occurred in design (concurrent data collection), analysis (qualitative data explaining quantitative patterns), and interpretation (synthesized findings addressing research questions from multiple perspectives). 3.5 Ethical Considerations Ethical approval obtained from Lagos State Health Research Ethics Committee (LSHREC/10/06/2021) and individual facilities. All participants provided written informed consent. Facility anonymity maintained through alphabetical codes; individual anonymity through role-based identifiers. Data stored securely with limited access. 3.6 Study Limitations Purposive facility selection limits statistical generalizability; social desirability bias may have influenced self-reports; resource constraints prevented environmental sampling for antimicrobial residues and resistant bacteria; limited access to waste companies restricted documentation of off-site practices; cross-sectional design captured specific timepoints without temporal variation assessment. Despite limitations, comprehensive mixed-methods design with multiple data sources provides robust evidence for main conclusions. 4. Results 4.1 Facility and Participant Characteristics Seven facilities served approximately 15,000 outpatients and 1,200 inpatients weekly. Among 336 questionnaire respondents: 31.4% nurses (n=106), 34.3% domestic workers/cleaners (n=115), 11.4% doctors (n=38), 10.5% laboratory scientists (n=35), and 3.8% other professionals (n=13). Mean age was 35.46±1.66 years; 53.3% female; average employment duration 9.73±6.91 years. 4.2 Waste Generation and Composition Total medical waste generation was 215.56 kg/day (average 0.181 kg/bed/day), varying by facility type: tertiary facility A generated 0.561 kg/bed/day, general hospital B generated 0.248 kg/bed/day, primary health centers 0.116-0.134 kg/bed/day, and private hospitals 0.198-0.267 kg/bed/day. Pharmaceutical waste - most relevant to AMR - was generated in all clinical areas, with highest volumes from pharmacies (20.0%), medical wards (16.2%), and surgical wards (16.2%). However, pharmaceutical waste segregation was notably poor, with frequent mixing with general or infectious waste. 4.3 Waste Segregation Practices Only 61.0% of respondents correctly identified that segregation should occur at source; 39.0% indicated otherwise or didn't know. When asked about actual locations, 52.2-90.0% reported source segregation (varying by facility), but 17.4-34.1% indicated segregation "outside the bin" or at collection points, suggesting remixing. Observational data confirmed frequent mixing: at Facility A, "everything a patient produces goes in the red bag regardless of whether it's infectious." At Facilities C and D, pharmaceutical waste including antimicrobials was observed disposed in general black bags or mixed with infectious waste. Color-coding knowledge varied: 58.1% correctly identified black for general waste, but only 33.3% correctly identified brown for pharmaceutical waste - critical for antimicrobial management. 4.4 Knowledge of Waste Categorization Assessment revealed significant variations with direct AMR implications. While 69.5% correctly categorized paper, food, and plastic as general waste, accuracy was lower for antimicrobial-containing materials. For soiled cotton wool, swabs, and gloves potentially containing antimicrobial residues, 69.5% correctly identified as infectious waste, but 11.4% incorrectly categorized as general waste. For pharmaceutical waste, only 58.1% correctly categorized body parts and fluids as pathological waste; 18.1% misclassified as infectious, 11.4% as general waste. Statistical analysis revealed significant associations between profession and categorization accuracy (χÇ=1344.000, p<0.001). Nurses demonstrated highest accuracy, followed by laboratory scientists, doctors, and cleaners. Domestic workers - handling majority of physical waste – showed lowest knowledge, representing a critical vulnerability. 4.5 Pharmaceutical and Antimicrobial Waste Management Identification and Segregation: Only 74.3% reported awareness of specific pharmaceutical waste procedures, leaving >25% without guidance. Observational data revealed inconsistent segregation: at Facility A's pharmacy, expired antimicrobials were stored in cardboard boxes with no clear disposal timeline; at private facilities, pharmaceutical waste had no specialized treatment beyond general pathways; at primary health centers, pharmaceutical waste including antimicrobials mixed with general or infectious waste. AMR Awareness: Only 42.6% of respondents aware that improper antimicrobial disposal contributes to environmental AMR. Awareness highest among doctors (73.7%) and laboratory scientists (68.6%), moderate among nurses (45.3%), lowest among domestic workers (18.3%). Infection control officers acknowledged AMR concerns but reported training rarely addressed AMR-waste connections explicitly. Treatment and Disposal: No facility reported specialized on-site treatment for pharmaceutical waste. All outsourced to LAWMA-accredited private sector participants (PSPs), with pharmaceutical waste treated through the same hydroclave process as other medical waste. However, hydroclave technology may not effectively degrade chemical antimicrobial compounds despite sterilizing biological materials. Post-treatment waste fate remained unclear. 4.6 Storage Practices and Duration WHO guidelines recommend storage not exceeding 24-48 hours (World Health Organization, 2021). Results revealed widespread non-compliance. On-Site Storage: At Facility A, bedside bins collected "four or five times daily," suggesting 2-6 hour storage at generation points. However, after ward collection, waste stored in temporary holding areas (sluice rooms) added several hours. At Facilities C and D, sluice room bins "collected when full" rather than scheduled, with cleaners reporting "sometimes one day, sometimes two days." Central Storage: Most significant violations occurred at central storage. All seven facilities reported LAWMA PSP collection "approximately weekly," with actual intervals 5-10 days depending on volume and schedules. During this period, waste stored in various conditions: open-sided structures (Facility A), enclosed unrefrigerated rooms (Facility B), outdoor bins (Facilities C, D, E, F, G). Storage areas typically: unrefrigerated (ambient 27-32°C), exposed to direct sunlight, not climate-controlled, high humidity (60-85%), and variably secured. These conditions are conducive to bacterial growth and horizontal gene transfer. The combination of prolonged storage (5-10 days vs. recommended 24-48 hours) and tropical conditions creates ideal environments for AMR amplification. 4.7 Waste Transportation and Treatment Internal Transport: Wheelbarrows and trolleys most common (68.2%), but manual carrying also observed. Notably, 26.8% indicated transport through clinical areas used by patients, creating exposure pathways. External Transport: Collection vehicles bore LAWMA markings but were often standard pickups with open beds or partially covered containers. No specialized containment observed for pharmaceutical waste. Collection frequency averaged weekly, though irregular. Multiple facilities reported: "Sometimes PSP doesn't come on schedule, so waste accumulates longer." Treatment: LAWMA operates centralized hydroclave treatment facility. However, concerns emerged: limited capacity relative to Lagos's waste generation; minimal treatment verification; pharmaceutical waste containing chemical antimicrobials may not be adequately degraded by hydroclave (sterilizes but doesn't chemically degrade); post-treatment disposal pathways unclear. Final Disposal: Ultimate waste fate remained most opaque element. Facility staff uniformly: "LAWMA takes it away, we don't know what happens after that." LAWMA officials: "After treatment, it's no longer medical waste, so it goes through normal disposal channels" - predominantly meaning open dumpsites or semi-controlled landfills where waste pickers commonly scavenge. Even if biological hazards eliminated, chemical antimicrobial compounds may persist and leach into soil and groundwater. 4.8 Staff Training and Knowledge Gaps While 74.3% reported receiving some training, quality, content, and frequency varied widely. Formal training most common at public facilities (85-95%) versus private facilities (60-75%) and primary health centers (25-45%). Training least common among cleaners: only 52.3% reported any training versus 89.5% of nurses and 94.7% of doctors. Training focused primarily on basic segregation, color-coding, and occupational safety. AMR-waste linkages rarely addressed: only 18.4% of trained respondents recalled AMR content; 12.7% recalled pharmaceutical waste content specifically. Training frequency inadequate: initial orientation with irregular refreshers "every few years, when budget allows." 4.9 Environmental Contamination Pathways While direct environmental sampling was beyond study scope, multiple contamination pathways emerged: Pathway 1 - Wastewater Discharge: All facilities disposed liquid waste (laboratory chemicals, disinfectants, pharmaceutical liquids) into sewage without treatment, delivering antimicrobial residues and resistant bacteria directly into wastewater systems. Pathway 2 - Storage Site Contamination: Storage sites showed contamination evidence: waste bags leaked onto floors and ground; rain infiltration mobilized contaminants; facilities lacking impermeable flooring allowed soil leaching; storm drains near storage provided pathways to stormwater systems. Pathway 3 - Transport Spillage: Transport created spillage potential: bags catching and breaking during facility movement; visible spillage during loading onto collection vehicles; open transport vehicles allowing aerosol generation and wind dispersal. Pathway 4 - Waste Picker Exposure: Despite security attempts, waste picking occurred, particularly at less-secure sites and final disposal locations. LAWMA officials acknowledged pickers access disposal sites: "We try to prevent it, but sites are large and difficult to secure completely." Pathway 5 - Occupational Exposure: Healthcare workers, especially cleaners, experienced direct exposure through needle stick injuries (23.8% reported at some point), contact despite glove use, inhalation of aerosols, and clothing/footwear contamination transferring resistant bacteria to homes and communities. 4.10 Policy and Institutional Framework National Policy Gaps: National policies provide general frameworks but have significant AMR limitations: pharmaceutical waste receives limited attention with no specialized antimicrobial requirements; AMR not explicitly mentioned as waste management rationale; environmental monitoring requirements absent; enforcement mechanisms weak with insufficient penalties; minimal integration with antimicrobial stewardship frameworks. Institutional Fragmentation: Responsibilities distributed across multiple agencies with unclear coordination, contributing to oversight gaps, inconsistent guidance, resource inefficiencies, and accountability diffusion. Implementation Deficits: Capacity constraints limit inspection abilities; financial limitations prevent infrastructure investments; technical gaps mean personnel lack understanding; political will varies with medical waste as lower priority. LAWMA/PSP Model: Outsourcing approach has advantages but limitations for AMR control: accountability diluted with facilities having limited oversight after collection; transparency limited with PSPs treating details as proprietary; cost pressures may incentivize corner-cutting; AMR-specific considerations absent from contracts and monitoring. 4.11 Resource and Capacity Constraints Financial Resources: All facilities reported inadequate budgets. Private facilities particularly struggled, with waste management fees representing significant operating costs, creating perverse incentives to minimize measured waste volume. Infrastructure Deficits: Inadequate storage facilities lacking climate control; insufficient color-coded containers; limited transport equipment; erratic personal protective equipment supplies. Human Resources: Staff shortages affected waste management: suboptimal cleaner-to-bed ratios; infection control officers with competing responsibilities; vacant or under-qualified environmental health positions; limited training capacity. Technical Capacity: Knowledge and skill gaps extended beyond frontline workers to management and oversight personnel, including administrators, infection control officers, and regulators. 4.12 Stakeholder Perspectives on AMR-Waste Linkages Healthcare Workers: Clinical staff had higher AMR awareness as clinical problem but lower awareness of environmental dimensions: "We think about resistance when prescribing... We don't usually think about waste management as part of the AMR problem." Waste Management Personnel: Cleaners had minimal AMR awareness generally and none regarding waste-AMR linkages: "I know about HIV and hepatitis from sharps... But antimicrobial resistance, I don't know about that." Administrators and Policymakers: Hospital administrators and LAWMA officials acknowledged AMR importance but hadn't considered waste management as contributing factor, expressing openness to interventions but emphasizing resource constraints. 5. Discussion 5.1 Medical Waste as AMR Vector in Lagos This study provides compelling evidence that inadequate medical waste management in Lagos creates multiple pathways for AMR dissemination. The finding that only 61% correctly identify segregation procedures, combined with frequent mixing of pharmaceutical waste with general streams, creates conditions where antimicrobial containing materials receive inadequate treatment and enter environmental compartments. At approximately 215 kg/day across surveyed facilities and likely exceeding 100,000 kg/day across Lagos's 500+ facilities, with pharmaceutical waste comprising 5-8% (suggesting 5,000-8,000 kg daily citywide), inadequate segregation and treatment means substantial antimicrobial quantities enter the environment with active compounds intact, exerting selective pressure for resistance (Singh et al., 2021; Khan et al., 2021). 5.2 Critical Control Point Failures Point of Generation: Inadequate segregation represents the most fundamental failure. Only 33.3% correctly identify pharmaceutical waste color-coding; observations showed routine mixing. This failure roots in insufficient training (particularly for cleaners with lowest knowledge), inadequate infrastructure (container stockouts), perverse incentives (minimizing measured volumes to reduce costs), and lack of AMR awareness. Storage Duration: Storage routinely exceeding 24-48 hour limits, with actual durations of 5-10 days, creates extended periods for bacterial proliferation, horizontal gene transfer, and resistance amplification. In tropical Lagos conditions (27-32°C, high humidity) in unrefrigerated facilities, these periods provide ideal circumstances for AMR amplification before waste reaches treatment. Treatment Adequacy: Reliance on hydroclave for all medical waste raises AMR adequacy questions. While hydroclave effectively sterilizes biological materials (killing resistant bacteria), it doesn't chemically degrade antimicrobial compounds that persist in treated waste and enter disposal sites (Giakoumakis et al., 2021; Kenny & Priyadarshini, 2021). Current treatment addresses only one AMR dimension (resistant bacteria) while failing another (antimicrobial selective pressure). Final Disposal: The opacity surrounding final disposal is most concerning. LAWMA's statement that treated waste "goes through normal disposal channels" suggests disposal in Lagos's municipal dumpsites where waste picking occurs and environmental controls are minimal. Even if biological hazards are eliminated, antimicrobial residues persisting in waste leach into soil and groundwater, contributing to sustained environmental contamination and selective pressure (Siddiqua et al., 2022). 5.3 Vulnerable Populations and Environmental Justice Findings illuminate environmental justice dimensions. Waste handlers, predominantly low-income cleaners, experience greatest occupational exposure but receive least training (52.3% vs. 89-95% for professional staff), reflecting systematic marginalization. These workers face daily exposure through direct contact, needle sticks (23.8% reported), and aerosol inhalation, often with inadequate personal protective equipment. Waste pickers at disposal sites represent another vulnerable population, experiencing exposure without even limited protections afforded formal healthcare workers. These marginalized individuals scavenge for recyclables unaware of AMR exposure (Cook & Velis, 2021; Schenck et al., 2019). Communities near waste storage and disposal sites experience environmental exposure through water contamination (leachate, runoff), soil contamination (spillage, leaks), air contamination (aerosols), and food chain contamination. This demonstrates AMR dissemination through medical waste exacerbates environmental inequities, adding another dimension to health disparities facing vulnerable populations (Pulido, 2017; Olaniyi et al., 2019). 5.4 Policy and Governance Challenges Nigeria's National Healthcare Waste Management Plan lacks AMR-specific provisions, reflecting broader disconnect between waste management and AMR policy domains. This siloed approach means waste policies focus on infection prevention and occupational safety without environmental AMR implications, while AMR policies focus on clinical use and surveillance without waste pathways (Ezirim & Agbo, 2018). Institutional fragmentation compounds gaps. Responsibilities across Federal Ministry of Health, Federal Ministry of Environment, NESREA, state agencies, and local departments create coordination challenges, accountability diffusion, and oversight gaps (Ezeudu et al., 2022). Implementation deficits further undermine existing policies: weak enforcement with minimal penalties; resource constraints limiting implementation and enforcement capacity; technical capacity gaps; and variable political will (Scholz, 2020; Lawless et al., 2020). 5.5 Integrated Framework for AMR-Oriented Waste Management Based on findings, we propose an integrated framework comprising five interconnected components: Component 1 - Enhanced Segregation at Point of Generation: Dedicated pharmaceutical waste containers in all areas with clear antimicrobial-specific markings; simplified color-coding with pharmaceutical waste distinctly identified; point-of-use decision aids helping correct categorization; regular segregation audits with staff feedback; integration into existing infection control systems. Component 2 - Safe Storage and Transport: Improved infrastructure with covered, secure facilities; more frequent collection (twice weekly minimum); cold storage/climate control for high-risk waste using low-cost options (shading, evaporative cooling); spill containment systems with impermeable flooring; dedicated enclosed transport. Component 3 - AMR-Targeted Treatment: Segregated treatment pathways with pharmaceutical waste receiving specialized treatment; enhanced technologies capable of degrading antimicrobial compounds (high-temperature incineration >850°C); treatment verification through periodic monitoring; technology assessment evaluating hydroclave adequacy for AMR control. Component 4 - Environmental Monitoring: Baseline environmental assessment characterizing antimicrobial contamination and resistant bacteria prevalence near facilities, storage sites, treatment facilities, and disposal sites; ongoing monitoring using sentinel antimicrobials, resistance genes, and resistant bacteria indicators; participatory approaches engaging communities and waste workers; data systems linking practices to environmental AMR outcomes. Component 5 - Integrated Policy and Governance: Policy integration incorporating AMR into waste management frameworks and vice versa; institutional coordination mechanisms addressing fragmentation; strengthened enforcement with increased penalties and inspection capacity; capacity building at all levels on AMR-waste linkages; sustainable financing mechanisms. 5.6 Implementation Barriers and Enabling Strategies Financial Constraints: Enable through efficiency gains from proper segregation; external financing (donors, government, extended producer responsibility); incremental implementation prioritizing high-impact, low-cost interventions (segregation, training) before infrastructure-intensive improvements. Technical Capacity Gaps: Enable through targeted training integrating AMR-waste content; mentorship and peer learning; simplified protocols and decision aids; partnerships with universities providing technical assistance. Institutional Fragmentation: Enable through high-level coordination mechanisms (inter-ministerial task forces); joint planning and implementation; shared accountability frameworks; integrated monitoring systems. Political and Cultural Factors: Enable through advocacy highlighting AMR-waste connections; community engagement raising awareness; identifying and supporting champions; alignment with existing priorities (infection prevention, occupational health, environmental protection). 5.7 Study Contributions This study contributes: detailed documentation of medical waste-AMR linkages in major African megacity addressing significant evidence gap; integrated socio-ecological framework recognizing complex system requiring multilevel interventions; demonstration of mixed-methods value combining quantitative assessment with qualitative contextual exploration; identification of specific policy gaps with evidence-based recommendations; and illumination of environmental justice dimensions documenting vulnerable population exposure. 5.8 Limitations and Future Directions Limitations include purposive sampling limiting statistical generalizability; potential social desirability bias; resource constraints preventing environmental sampling for antimicrobial residues and resistant bacteria - a significant gap requiring future research; limited access to private operators preventing detailed documentation beyond facility handoff; and cross-sectional design without temporal variation assessment. Future research directions include: environmental monitoring studies directly measuring antimicrobial residues and resistant bacteria in wastewater, soil, water, and air; intervention research evaluating specific improvement effectiveness; health impact assessment linking environmental contamination to community health outcomes; economic analysis examining cost-benefit of improved approaches; comparative research across diverse settings; and social science research examining risk perceptions and behaviors. 6. Conclusion This study provides comprehensive documentation of critical intersections between medical waste management and antimicrobial resistance in Lagos, revealing systematic deficiencies creating multiple pathways for AMR dissemination through environmental contamination. Across seven diverse healthcare facilities, findings demonstrate that inadequate segregation (only 61% proper), prolonged storage (5–10 days vs. recommended 24–48 hours), insufficient treatment (hydroclave sterilizes but doesn't degrade antimicrobials), and opaque disposal combine to enable antimicrobial residues and resistant bacteria to enter environmental compartments with minimal control. The magnitude is substantial: approximately 215 kg/day across surveyed facilities (translating to likely > 100,000 kg/day citywide), with 5–8% pharmaceutical waste including antimicrobials; only 33.3% correct identification of pharmaceutical waste protocols, resulting in routine mixing with general streams; storage in tropical conditions (27–32°C) conducive to bacterial proliferation and gene transfer; treatment failing to degrade antimicrobial compounds that persist into disposal sites; and absent environmental monitoring leaving contamination levels unmeasured. These findings reveal medical waste as significant yet underrecognized AMR propagation vector in rapidly urbanizing African contexts. While clinical antimicrobial use receives considerable AMR discourse attention, this study demonstrates waste management failures create parallel pathways through which resistant bacteria and antimicrobial selective pressure disseminate in communities. Environmental AMR dimensions extend resistance development and transmission beyond healthcare settings into community environments where exposure occurs through contaminated water and soil, occupational contact, scavenging, and ecosystem-wide microbial impacts. Environmental justice analysis reveals AMR dissemination through waste disproportionately impacts vulnerable populations. Waste handlers experience highest occupational exposure yet receive least training (52.3% vs. 89–95% for professional staff). Communities near waste sites experience environmental exposure through water, soil, and air contamination. Waste pickers experience direct contact while earning subsistence livelihoods. These exposure distributions reflect and exacerbate existing health inequities, adding AMR risks to multiple environmental health burdens already borne by vulnerable populations. Policy analysis identifies critical gaps Nigeria's National Healthcare Waste Management Plan lacks AMR-specific provisions; institutional fragmentation creates coordination challenges and accountability diffusion; weak enforcement fails to compel compliance; privatization through LAWMA/PSP improves some dimensions but creates transparency and accountability gaps particularly regarding AMR concerns. The proposed integrated framework offers evidence-based pathways through enhanced segregation with pharmaceutical waste specifically identified; safe storage and transport with reduced duration and environmental exposure; AMR-targeted treatment using technologies degrading antimicrobial compounds; environmental monitoring establishing baseline contamination and tracking effects; and integrated policy addressing fragmentation while incorporating AMR considerations into waste frameworks and waste considerations into AMR frameworks. Implementation requires addressing financial constraints, technical capacity gaps, institutional fragmentation, and political prioritization through enabling strategies including external financing, capacity building partnerships, high-level coordination mechanisms, and advocacy elevating waste management within AMR discourse. Incremental approaches prioritizing high-impact, low-cost interventions (segregation, training) before infrastructure-intensive improvements (treatment technology upgrades) can enable progress within resource constraints while building toward comprehensive solutions. This research demonstrates that effective AMR control requires expanding traditional clinical focus (antimicrobial prescribing, infection prevention within healthcare facilities) to encompass environmental pathways through which resistance propagates in communities. Medical waste management represents a critical yet neglected component of comprehensive AMR responses. In rapidly urbanizing developing country contexts like Lagos - where healthcare systems are expanding, waste generation is increasing, and management infrastructure is inadequate – addressing waste-AMR linkages is essential for protecting population health and environmental sustainability. The findings from Lagos have broader significance for many African and global cities experiencing similar convergence: rapid urbanization, expanding healthcare access, increasing antimicrobial use, inadequate waste infrastructure, and vulnerable populations at risk. While specific contexts vary, fundamental dynamics documented here - inadequate segregation, prolonged storage, insufficient treatment, environmental contamination, vulnerable population exposure - likely occur across diverse settings. The integrated framework offers adaptable principles for addressing waste-AMR linkages in resource-constrained contexts, requiring contextualization but providing strategic direction. Ultimately, this study reinforces that AMR is not merely a clinical problem amenable to clinical solutions alone, but rather a complex socio-ecological challenge requiring coordinated interventions across healthcare, environment, governance, and community domains. Medical waste management, positioned at the intersection of these domains, offers an intervention point where relatively feasible improvements can yield substantial AMR control benefits while simultaneously addressing infection prevention, occupational health, environmental protection, and health equity objectives. Realizing this potential requires political will, resource mobilization, technical capacity building, and sustained commitment - challenges certainly, but not insurmountable ones given the stakes for public health in an era of escalating antimicrobial resistance. Declarations Ethics approval and consent to participate Ethical approval for this study was obtained from the Lagos Waste Management Authority (LAWMA) . All participants provided informed consent prior to participation. This study was conducted in accordance with the principles of the Declaration of Helsinki . Consent for publication Not applicable (Participants were not identifiable and no personal data was published.) Competing interests The authors declare no competing interests . Funding Declaration This research received no external funding . All aspects of the study, data collection, analysis, and manuscript preparation were conducted without financial support from any public, commercial, or not-for-profit funding agency. Clinical Trial Registration Clinical trial number: Not applicable. This study did not involve any clinical trial or clinical intervention requiring registration. Ethics Declaration All participants provided informed consent prior to participation. No animals, clinical interventions, or patient-identifying information were involved. Availability of data and materials The data supporting the findings of this study are available from the corresponding author upon request. Due to confidentiality agreements with participating healthcare facilities, raw data cannot be made publicly accessible. Author Contributions Conceptualization: Yusuf, Gbolahan Afeez Methodology: Yusuf, Gbolahan Afeez; Olaleye, Oluremi Nurudeen Data Collection: Yusuf, Gbolahan Afeez Analysis & Interpretation: Yusuf, Gbolahan Afeez; Olaleye, Oluremi Nurudeen Writing - Original Draft: Yusuf, Gbolahan Afeez Writing - Review & Editing: Yusuf, Gbolahan Afeez; Olaleye, Oluremi Nurudeen All authors reviewed and approved the final manuscript. Conflict of Interest Declaration The authors declare no competing financial or personal interests that could have influenced the work reported in this paper. References Adetola, I. M. (2023). Innovative solutions to waste management: A case study of Lagos State, Nigeria. Master Thesis, Rhein-Waal University of Applied Sciences. Andeobu, L., Wibowo, S., & Grandhi, S. (2022). Medical waste from COVID-19 pandemic - A systematic review of management and environmental impacts in Australia. International Journal of Environmental Research and Public Health, 19(3), 1381. Awodele, O., Adewoye, A. A., & Oparah, A. C. (2016). Assessment of medical waste management in seven hospitals in Lagos, Nigeria. BMC Public Health, 16(269). Chisholm, J. M., Zamani, R., Negm, A. M., Said, N., Abdel daiem, M. M., Dibaj, M., & Akrami, M. (2021). Sustainable waste management of medical waste in African developing countries: A narrative review. Waste Management & Research, 39(9), 1149-1163. Cook, E., & Velis, C. A. (2021). Global review on safer end of engineered life. White Rose Research. Corvalan, C., Prats, E. V., Sena, A., Campbell-Lendrum, D., Karliner, J., Risso, A., & Heymann, D. (2020). Towards climate resilient and environmentally sustainable health care facilities. International Journal of Environmental Research and Public Health, 17(23), 8849. Das, A. K., Islam, M. N., Billah, M. M., & Sarker, A. (2021). COVID-19 pandemic and healthcare solid waste management strategy – A mini-review. Science of The Total Environment, 778, 146220. Ezirim, I., & Agbo, F. (2018). Role of national policy in improving health care waste management in Nigeria. Journal of Health & Pollution, 8(19), 180913. Ezeudu, O. B., Ezeudu, T. S., Ugochukwu, U. C., Agunwamba, J. C., & Oraelosi, T. C. (2022). Healthcare waste management in Nigeria: A review. Recycling, 7(87), 1-16. Ferronato, N., & Vincenzo, T. (2019). Waste mismanagement in developing countries: A review of global issues. International Journal of Environmental Research and Public Health, 16(6), 1060. Giakoumakis, G., Politi, D., & Sidiras, D. (2021). Medical waste treatment technologies for energy, fuels, and materials production: A review. Energies, 14(23), 8065. Hantoko, D., Li, X., Pariatamby, A., Yoshikawa, K., Horttanainen, M., & Yan, M. (2021). Challenges and practices on waste management and disposal during COVID-19 pandemic. Journal of Environmental Management, 286, 112140. Harrison, R. L., Reilly, T. M., & Creswell, J. W. (2020). Methodological rigor in mixed methods: An application in management studies. Journal of Mixed Methods Research, 14(4), 473-495. Hassan, E. R., Zada, E., Gintamo, B., Mekuria, Z. N., & Gizaw, Z. (2021). Planning for disposal of COVID-19 pandemic wastes in developing countries: A review of current challenges. Environmental Science and Pollution Research, 193(9), 592-603. Jones, J. A., & Donmoyer, R. (2021). Improving the trustworthiness/validity of interview data in qualitative nonprofit sector research. Nonprofit and Voluntary Sector Quarterly, 50(4), 889-904. Kenny, C., & Priyadarshini, A. (2021). Review of current healthcare waste management methods and their effect on global health. Healthcare, 9(3), 284. Khalid, S., Haq, N., Sabiha, Z., Latif, A., Khan, M. A., Iqbal, J., & Yousaf, N. (2021). Current practices of waste management in teaching hospitals and presence of incinerators in densely populated areas. BMC Public Health, 21(1340). Khan, B. A., Cheng, L., Khan, A. A., & Ahmed, H. (2019). Healthcare waste management in Asian developing countries: A mini review. Waste Management & Research, 37(9), 863-875. Khan, N. A., Vambol, V., Vambol, S., Bolibrukh, B., Sillanpaa, M., Changani, F., & Yousefi, M. (2021). Hospital effluent guidelines and legislation scenario around the globe: A critical review. Journal of Environmental Chemical Engineering, 9(5), 105874. Lawless, S., Song, A. M., Cohen, P. J., & Morrison, T. H. (2020). Rights, equity and justice: A diagnostic for social meta-norm diffusion in environmental governance. Earth System Governance, 6, 100052. Marfe, G., & Stefano, C. D. (2020). Risks and challenges of hazardous waste management: Reviews and case studies. Bentham Science Publishers. Navarro, F., & Vincenzo, T. (2019). Waste mismanagement in developing countries: A review of global issues. International Journal of Environmental Research and Public Health, 16(6), 1060. Njoku, P. O., Edokpayi, J. N., & Odiyo, J. O. (2019). Health and environmental risks of residents living close to a landfill: A case study of Thohoyandou Landfill, Limpopo Province, South Africa. International Journal of Environmental Research and Public Health, 16(12), 2059. Olaniyi, F. C., Ogola, J. S., & Tshitangano, T. G. (2019). Efficiency of health care risk waste management in rural healthcare facilities of South Africa: An assessment of selected facilities. International Journal of Environmental Research and Public Health, 16(12), 2199. Olukanni, D. O., Lazarus, J. D., & Fagbenle, E. (2022). Healthcare waste management practices in Nigeria: A review. In S. Ghosh & P. Agamuthu (Eds.), Health care waste management and COVID 19 pandemic. Springer. Padmanabhan, K., & Barik, D. (2019). Health hazards of medical waste and its disposal. In D. Barik (Ed.), Energy from toxic organic waste for heat and power generation (pp. 99-118). Woodhead Publishing. Pulido, L. (2017). Environmental racism. In D. Richardson (Ed.), The international encyclopedia of geography. Wiley-Blackwell. Renjith, V., Yesodharan, R., Noronha, J. A., Ladd, E., & George, A. (2021). Qualitative methods in health care research. International Journal of Preventive Medicine, 12, 20. Sangkham, S. (2020). Face mask and medical waste disposal during the novel COVID-19 pandemic in Asia. Case Studies in Chemical and Environmental Engineering, 2, 100052. Schenck, C. J., Blaauw, P. F., Viljoen, J., & Swart, E. C. (2019). Exploring the potential health risks faced by waste pickers on landfills in South Africa: A socio-ecological perspective. International Journal of Environmental Research and Public Health, 16(2059). Scholz, N. (2020). Addressing health inequalities in the European Union. European Parliamentary Research Service. Sibanda, P. (2019). Health and socioeconomic analysis of waste picking activities in Durban [Master's thesis, University of KwaZulu-Natal]. Siddiqua, A., Hahladakis, J. N., & Al-Attiya, W. A. (2022). An overview of the environmental pollution and health effects associated with waste landfilling and open dumping. Environmental Science and Pollution Research, 29, 58514–58536. Singh, N., Ogunseitan, O. A., & Tang, Y. (2021). Medical waste: Current challenges and future opportunities for sustainable management. Critical Reviews in Environmental Science and Technology, 52(11), 1915-1945. World Health Organization. (2021). Global progress report on HIV, viral hepatitis and sexually transmitted infections, 2021. WHO Additional Declarations No competing interests reported. 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Introduction","content":"\u003cp\u003e\u003cstrong\u003e1.1 Background and Significance\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAntimicrobial resistance threatens to cause 10 million deaths annually by 2050 if current trends continue (World Health Organization, 2021). While clinical antimicrobial use receives considerable attention as an AMR driver, environmental contamination through inadequate medical waste management remains critically underexamined, particularly in low- and middle-income countries with deficient waste infrastructure (Khan et al., 2019). Healthcare facilities generate substantial waste containing antimicrobial residues, resistant bacteria, and mobile genetic elements - materials that, when improperly managed, contribute significantly to AMR dissemination in environmental compartments (Singh et al., 2021).\u003c/p\u003e\n\u003cp\u003eNigeria exemplifies the convergence of factors amplifying AMR risks through medical waste pathways. The country\u0026apos;s healthcare system generates over 500,000 tons of medical waste annually yet lacks comprehensive treatment and disposal infrastructure (Ezeudu et al., 2022). Lagos State, with 20+ million inhabitants and serving as Nigeria\u0026apos;s commercial center, faces particularly acute challenges as concentrated healthcare facilities, rapid urbanization, and inadequate waste management systems create conditions conducive to AMR propagation\u003c/p\u003e\n\u003cp\u003e(Olukanni et al., 2022).\u003c/p\u003e\n\u003cp\u003eThe medical waste-AMR nexus operates through multiple mechanisms: pharmaceutical waste containing active antimicrobial compounds creates selective pressure for resistance development in environmental bacteria (Navarro \u0026amp; Vincenzo, 2019); infectious waste from antimicrobial-treated patients harbors resistant bacteria capable of horizontal gene transfer to environmental microorganisms (Das et al., 2021); contaminated sharps and laboratory waste serve as transmission vectors to waste handlers and communities (Chisholm et al., 2021); and inadequate treatment facilities fail to inactivate antimicrobial compounds and resistant bacteria before disposal, allowing environmental persistence (Sangkham, 2020).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.2 Research Gap and Objectives\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhile existing literature documents medical waste management deficiencies in developing countries, the specific linkage between these practices and AMR propagation remains inadequately explored. Most studies address waste management or AMR in isolation, without examining mechanistic connections and environmental pathways through which inadequate waste practices contribute to resistance dissemination (Khan et al., 2019). This study addresses this\u003c/p\u003e\n\u003cp\u003egap by systematically examining medical waste management in Lagos healthcare facilities through an AMR lens, documenting environmental contamination pathways, and proposing integrated interventions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjectives:\u003c/strong\u003e\u003c/p\u003e\n\u003col style=\"list-style-type: lower-roman;\"\u003e\n \u003cli\u003eAssess current medical waste management practices with specific attention to antimicrobial-containing materials\u003c/li\u003e\n \u003cli\u003eIdentify environmental contamination pathways facilitating AMR dissemination\u003c/li\u003e\n \u003cli\u003eEvaluate policy and institutional frameworks governing medical waste management and their adequacy for addressing AMR risks\u003c/li\u003e\n \u003cli\u003eDevelop evidence-based recommendations integrating AMR considerations into waste management policies and practices\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"2. Literature Review","content":"\u003cp\u003e\u003cstrong\u003e2.1 AMR and Environmental Dimensions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAntimicrobial resistance has evolved from clinical curiosity to global health emergency, with environmental compartments serving as critical reservoirs and transmission pathways for resistance genes and resistant bacteria (Khan et al., 2021). Healthcare facilities contribute significantly through wastewater discharge, pharmaceutical waste disposal, and inadequate infectious waste treatment (Hassan et al., 2021). These environmental reservoirs facilitate\u003c/p\u003e\n\u003cp\u003ehorizontal gene transfer between bacterial species, creating opportunities for resistance dissemination beyond original hosts (Njoku et al., 2019).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 Medical Waste as AMR Vector\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMedical waste represents a particularly concerning AMR vector due to concentrated antimicrobial agents, resistant microorganisms, and conducive environmental conditions throughout the waste management chain (Hantoko et al., 2021). Infectious waste from antimicrobial-treated patients contains resistant bacteria; pharmaceutical waste includes active antimicrobials maintaining selective pressure; laboratory waste harbors cultured resistant organisms; and sharps contaminated with blood from treated patients serve as direct transmission vectors (Olaniyi et al., 2019).\u003c/p\u003e\n\u003cp\u003eMechanisms operate at multiple scales: antimicrobial compounds in pharmaceutical waste exert selective pressure on environmental bacterial populations (Andeobu et al., 2022); waste disposal sites create microenvironments with elevated bacterial density and stress conditions enhancing horizontal gene transfer (Chisholm et al., 2021); waste handlers, scavengers, and communities experience direct exposure through occupational contact and environmental contamination (Ezeudu et al., 2022).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 Medical Waste Management in Developing Countries\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStudies across Asia, Africa, and Latin America document common deficiencies: inadequate segregation mixing infectious and pharmaceutical wastes with general waste (Khan et al., 2019); insufficient treatment infrastructure (Ferronato \u0026amp; Vincenzo, 2019); prolonged storage exceeding recommended timeframes (Olaniyi et al., 2019); unsafe transport exposing waste handlers (Padmanabhan \u0026amp; Barik, 2019); and inadequate final disposal with untreated medical waste in open dumps (Singh et al., 2021). These deficiencies reflect broader constraints: insufficient\u003c/p\u003e\n\u003cp\u003efunding, limited technical capacity, weak regulatory enforcement, rapid healthcare expansion without corresponding waste planning, and competing priorities (Chisholm et al., 2021).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.4 The Nigerian Context\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNigeria\u0026apos;s policy framework includes the National Policy on Injection Safety and Healthcare Waste Management (2007) and National Healthcare Waste Management Plan, but implementation remains inconsistent (Ezirim \u0026amp; Agbo, 2018). Lagos has developed more robust infrastructure than most Nigerian regions, including the Lagos Waste Management Authority (LAWMA) medical waste unit, hydroclave treatment facilities, and private sector participation (Adetola, 2023). Despite these advances, studies document persistent deficiencies: inadequate\u003c/p\u003e\n\u003cp\u003esegregation, treatment capacity constraints, prolonged storage, and limited verification of disposal practices (Olukanni et al., 2022). Pharmaceutical waste handling receives insufficient attention in protocols and practices (Awodele et al., 2016).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.5 Environmental AMR Pathways\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePathways through which inadequate treatment of medical waste contributes to environmental AMR include: wastewater discharge carrying antimicrobial residues and resistant bacteria (Khan et al., 2021); leachate from disposal sites contaminating groundwater and surface water (Siddiqua et al., 2022); aerosol generation during incineration dispersing resistant bacteria (Khalid et al., 2021); soil contamination creating resistance gene reservoirs (Marfe \u0026amp; Stefano, 2020); and direct exposure of waste handlers and communities (Cook \u0026amp; Velis, 2021).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.6 Theoretical Framework\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research adopts an integrated socio-ecological framework recognizing AMR dissemination through medical waste as a complex system involving interactions across individual (healthcare worker practices), facility (infrastructure, management), policy (regulations, enforcement), community (exposure pathways), and environmental (AMR reservoirs) levels (Corvalan et al., 2020). The framework incorporates environmental justice perspectives recognizing vulnerable populations bear disproportionate risks (Pulido, 2017) and political economy perspectives situating challenges within broader structural inequalities (Sibanda, 2019).\u003c/p\u003e"},{"header":"3. Methodology","content":"\u003cp\u003e\u003cstrong\u003e3.1 Study Design and Setting\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis concurrent mixed-methods study combined quantitative assessments with qualitative exploration of stakeholder perspectives, policy frameworks, and contamination pathways (Harrison et al., 2020). Conducted October 2021 - March 2022 in Lagos State\u0026apos;s Alimosho and Mushin Local Government Areas, the study selected Lagos due to its status as Nigeria\u0026apos;s largest city, concentration of healthcare facilities (25% of country\u0026apos;s private sector), relatively advanced waste infrastructure, and availability of comparative data (Olukanni et al., 2022).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2 Sample Selection and Size\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHealthcare facilities were selected using stratified purposive sampling across public tertiary, public secondary, public primary, and private facilities. Final sample comprised seven facilities: one federal teaching hospital (Facility A, 450 beds), one state general hospital (Facility B, 180 beds), two primary health centers (Facilities C and D, 15-20 beds each), and three private hospitals (Facilities E, F, G, 30-50 beds each). For quantitative components, Cochran\u0026apos;s formula [n = (Z\u0026Ccedil;pq)/E\u0026Ccedil;] with Z=1.96, p=0.5, E=0.05 yielded required sample size of 384. From 400 distributed questionnaires, 336 were completed (87.5% response rate). Qualitative sampling engaged key stakeholders: facility administrators (n=7), infection control officers (n=7), nurses (n=12), laboratory personnel (n=8), cleaners (n=10), LAWMA officials (n=3), and private operators (n=2), continuing until thematic saturation (Renjith et al., 2021).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3 Data Collection Methods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFacility Assessment: Structured assessments documented waste generation rates and composition, segregation practices, storage infrastructure and duration, treatment capabilities, transport arrangements, disposal verification, and staff training. Each facility received 3-5 visits over the study period.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eQuestionnaire Survey:\u003c/strong\u003e Structured questionnaires administered to healthcare workers comprised six sections: demographics (10 items), waste categorization knowledge with AMR-specific items (15 items), segregation practices (12 items), storage and transport (8 items), training (6 items), and AMR-waste linkages awareness (10 items). Pilot testing with 20 workers refined the instrument.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSemi-Structured Interviews:\u003c/strong\u003e In-depth interviews with key informants explored current practices, pharmaceutical/antimicrobial waste handling, AMR-waste awareness, policy frameworks, constraints, and improvement recommendations. Interviews lasted 30-75 minutes; with consent, were audio-recorded and transcribed verbatim.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObservational Data:\u003c/strong\u003e Systematic observation documented practices at waste generation points, collection points, during transport, at transfer stations, and treatment/disposal facilities (where access permitted).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDocument Review:\u003c/strong\u003e Analysis of national policies, facility records, regulatory documents, and international guidelines provided contextual understanding and identified policy-practice gaps.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4 Data Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eQuantitative:\u003c/strong\u003e SPSS version 26 analyzed questionnaire and facility data using descriptive statistics and chi-square tests examining associations between variables (significance p\u0026lt;0.05).\u003c/p\u003e\n\u003cp\u003eQualitative: Thematic analysis following Braun and Clarke\u0026apos;s framework coded interviews, observations, and documents using NVivo 12. Codebook developed iteratively organized codes into thematic categories. Inter-coder reliability (Cohen\u0026apos;s Kappa=0.82) confirmed substantial agreement (Jones \u0026amp; Donmoyer, 2021).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIntegration:\u003c/strong\u003e Mixed-methods integration occurred in design (concurrent data collection), analysis (qualitative data explaining quantitative patterns), and interpretation (synthesized findings addressing research questions from multiple perspectives).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.5 Ethical Considerations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval obtained from Lagos State Health Research Ethics Committee (LSHREC/10/06/2021) and individual facilities. All participants provided written informed consent. Facility anonymity maintained through alphabetical codes; individual anonymity through role-based identifiers. Data stored securely with limited access.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.6 Study Limitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePurposive facility selection limits statistical generalizability; social desirability bias may have influenced self-reports; resource constraints prevented environmental sampling for antimicrobial residues and resistant bacteria; limited access to waste companies restricted documentation of off-site practices; cross-sectional design captured specific timepoints without temporal variation assessment. Despite limitations, comprehensive mixed-methods design with multiple data sources provides robust evidence for main conclusions.\u003c/p\u003e"},{"header":"4. Results","content":"\u003cp\u003e\u003cstrong\u003e4.1 Facility and Participant Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSeven facilities served approximately 15,000 outpatients and 1,200 inpatients weekly. Among 336 questionnaire respondents: 31.4% nurses (n=106), 34.3% domestic workers/cleaners (n=115), 11.4% doctors (n=38), 10.5% laboratory scientists (n=35), and 3.8% other professionals (n=13). Mean age was 35.46\u0026plusmn;1.66 years; 53.3% female; average employment duration 9.73\u0026plusmn;6.91 years.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.2 Waste Generation and Composition\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTotal medical waste generation was 215.56 kg/day (average 0.181 kg/bed/day), varying by facility type: tertiary facility A generated 0.561 kg/bed/day, general hospital B generated 0.248 kg/bed/day, primary health centers 0.116-0.134 kg/bed/day, and private hospitals 0.198-0.267 kg/bed/day. Pharmaceutical waste - most relevant to AMR - was generated in all clinical areas, with highest volumes from pharmacies (20.0%), medical wards (16.2%), and surgical wards (16.2%). However, pharmaceutical waste segregation was notably poor, with frequent mixing with general or infectious waste.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.3 Waste Segregation Practices\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOnly 61.0% of respondents correctly identified that segregation should occur at source; 39.0% indicated otherwise or didn\u0026apos;t know. When asked about actual locations, 52.2-90.0% reported source segregation (varying by facility), but 17.4-34.1% indicated segregation \u0026quot;outside the bin\u0026quot; or at collection points, suggesting remixing. Observational data confirmed frequent mixing: at Facility A, \u0026quot;everything a patient produces goes in the red bag regardless of whether it\u0026apos;s infectious.\u0026quot; At Facilities C and D, pharmaceutical waste including antimicrobials was observed disposed in general black bags or mixed with infectious waste.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eColor-coding knowledge varied:\u003c/strong\u003e 58.1% correctly identified black for general waste, but only 33.3% correctly identified brown for pharmaceutical waste - critical for antimicrobial management.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.4 Knowledge of Waste Categorization\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAssessment revealed significant variations with direct AMR implications. While 69.5% correctly categorized paper, food, and plastic as general waste, accuracy was lower for antimicrobial-containing materials. For soiled cotton wool, swabs, and gloves potentially containing antimicrobial residues, 69.5% correctly identified as infectious waste, but 11.4% incorrectly categorized as general waste. For pharmaceutical waste, only 58.1% correctly categorized body parts and fluids as pathological waste; 18.1% misclassified as infectious, 11.4% as general waste. Statistical analysis revealed significant associations between profession and categorization accuracy (\u0026chi;\u0026Ccedil;=1344.000, p\u0026lt;0.001). Nurses demonstrated highest accuracy, followed by\u003c/p\u003e\n\u003cp\u003elaboratory scientists, doctors, and cleaners. Domestic workers - handling majority of physical waste \u0026ndash; showed lowest knowledge, representing a critical vulnerability.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.5 Pharmaceutical and Antimicrobial Waste Management\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIdentification and Segregation: Only 74.3% reported awareness of specific pharmaceutical waste procedures, leaving \u0026gt;25% without guidance. Observational data revealed inconsistent segregation: at Facility A\u0026apos;s pharmacy, expired antimicrobials were stored in cardboard boxes with no clear disposal timeline; at private facilities, pharmaceutical waste had no specialized treatment beyond general pathways; at primary health centers, pharmaceutical waste including antimicrobials mixed with general or infectious waste.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAMR Awareness:\u003c/strong\u003e Only 42.6% of respondents aware that improper antimicrobial disposal contributes to environmental AMR. Awareness highest among doctors (73.7%) and laboratory scientists (68.6%), moderate among nurses (45.3%), lowest among domestic workers (18.3%). Infection control officers acknowledged AMR concerns but reported training rarely addressed AMR-waste connections explicitly.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTreatment and Disposal:\u003c/strong\u003e No facility reported specialized on-site treatment for pharmaceutical waste. All outsourced to LAWMA-accredited private sector participants (PSPs), with pharmaceutical waste treated through the same hydroclave process as other medical waste. However, hydroclave technology may not effectively degrade chemical antimicrobial compounds despite sterilizing biological materials. Post-treatment waste fate remained unclear.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.6 Storage Practices and Duration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWHO guidelines recommend storage not exceeding 24-48 hours (World Health Organization, 2021). Results revealed widespread non-compliance.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eOn-Site Storage:\u003c/strong\u003e At Facility A, bedside bins collected \u0026quot;four or five times daily,\u0026quot; suggesting 2-6 hour storage at generation points. However, after ward collection, waste stored in temporary holding areas (sluice rooms) added several hours. At Facilities C and D, sluice room bins \u0026quot;collected when full\u0026quot; rather than scheduled, with cleaners reporting \u0026quot;sometimes one day, sometimes two days.\u0026quot;\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCentral Storage:\u003c/strong\u003e Most significant violations occurred at central storage. All seven facilities reported LAWMA PSP collection \u0026quot;approximately weekly,\u0026quot; with actual intervals 5-10 days depending on volume and schedules. During this period, waste stored in various conditions: open-sided structures (Facility A), enclosed unrefrigerated rooms (Facility B), outdoor bins (Facilities C, D, E, F, G). Storage areas typically: unrefrigerated (ambient 27-32\u0026deg;C), exposed to direct sunlight, not climate-controlled, high humidity (60-85%), and variably secured. These conditions are conducive to bacterial growth and horizontal gene transfer. The combination of prolonged storage (5-10 days vs. recommended 24-48 hours) and tropical conditions creates ideal environments for AMR amplification.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.7 Waste Transportation and Treatment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInternal Transport:\u003c/strong\u003e Wheelbarrows and trolleys most common (68.2%), but manual carrying also observed. Notably, 26.8% indicated transport through clinical areas used by patients, creating exposure pathways.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eExternal Transport:\u003c/strong\u003e Collection vehicles bore LAWMA markings but were often standard pickups with open beds or partially covered containers. No specialized containment observed for pharmaceutical waste. Collection frequency averaged weekly, though irregular. Multiple facilities reported: \u0026quot;Sometimes PSP doesn\u0026apos;t come on schedule, so waste accumulates longer.\u0026quot;\u003c/p\u003e\n\u003cp\u003eTreatment: LAWMA operates centralized hydroclave treatment facility. However, concerns emerged: limited capacity relative to Lagos\u0026apos;s waste generation; minimal treatment verification; pharmaceutical waste containing chemical antimicrobials may not be adequately degraded by hydroclave (sterilizes but doesn\u0026apos;t chemically degrade); post-treatment disposal pathways unclear.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eFinal Disposal:\u003c/strong\u003e Ultimate waste fate remained most opaque element. Facility staff uniformly: \u0026quot;LAWMA takes it away, we don\u0026apos;t know what happens after that.\u0026quot; LAWMA officials: \u0026quot;After treatment, it\u0026apos;s no longer medical waste, so it goes through normal disposal channels\u0026quot; - predominantly meaning open dumpsites or semi-controlled landfills where waste pickers commonly scavenge. Even if biological hazards eliminated, chemical antimicrobial compounds\u003c/p\u003e\n\u003cp\u003emay persist and leach into soil and groundwater.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.8 Staff Training and Knowledge Gaps\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhile 74.3% reported receiving some training, quality, content, and frequency varied widely. Formal training most common at public facilities (85-95%) versus private facilities (60-75%) and primary health centers (25-45%).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTraining least common among cleaners:\u003c/strong\u003e only 52.3% reported any training versus 89.5% of nurses and 94.7% of doctors. Training focused primarily on basic segregation, color-coding, and occupational safety.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAMR-waste linkages rarely addressed:\u003c/strong\u003e only 18.4% of trained respondents recalled AMR content; 12.7% recalled pharmaceutical waste content specifically. Training frequency inadequate: initial orientation with irregular refreshers \u0026quot;every few years, when budget allows.\u0026quot;\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.9 Environmental Contamination Pathways\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhile direct environmental sampling was beyond study scope, multiple contamination pathways emerged:\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePathway 1 - Wastewater Discharge:\u003c/strong\u003e All facilities disposed liquid waste (laboratory chemicals, disinfectants, pharmaceutical liquids) into sewage without treatment, delivering antimicrobial residues and resistant bacteria directly into wastewater systems.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePathway 2 - Storage Site Contamination:\u003c/strong\u003e Storage sites showed contamination evidence: waste bags leaked onto floors and ground; rain infiltration mobilized contaminants; facilities lacking impermeable flooring allowed soil leaching; storm drains near storage provided pathways to stormwater systems.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePathway 3 - Transport Spillage:\u003c/strong\u003e Transport created spillage potential: bags catching and breaking during facility movement; visible spillage during loading onto collection vehicles; open transport vehicles allowing aerosol generation and wind dispersal.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePathway 4 - Waste Picker Exposure:\u003c/strong\u003e Despite security attempts, waste picking occurred, particularly at less-secure sites and final disposal locations. LAWMA officials acknowledged pickers access disposal sites: \u0026quot;We try to prevent it, but sites are large and difficult to secure completely.\u0026quot;\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePathway 5 - Occupational Exposure:\u003c/strong\u003e Healthcare workers, especially cleaners, experienced direct exposure through needle stick injuries (23.8% reported at some point), contact despite glove use, inhalation of aerosols, and clothing/footwear contamination transferring resistant bacteria to homes and communities.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.10 Policy and Institutional Framework\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNational Policy Gaps:\u003c/strong\u003e National policies provide general frameworks but have significant AMR limitations: pharmaceutical waste receives limited attention with no specialized antimicrobial requirements; AMR not explicitly mentioned as waste management rationale; environmental monitoring requirements absent; enforcement mechanisms weak with insufficient penalties; minimal integration with antimicrobial stewardship frameworks.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eInstitutional Fragmentation:\u003c/strong\u003e Responsibilities distributed across multiple agencies with unclear coordination, contributing to oversight gaps, inconsistent guidance, resource inefficiencies, and accountability diffusion.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eImplementation Deficits:\u003c/strong\u003e Capacity constraints limit inspection abilities; financial limitations prevent infrastructure investments; technical gaps mean personnel lack understanding; political will varies with medical waste as lower priority.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eLAWMA/PSP Model:\u003c/strong\u003e Outsourcing approach has advantages but limitations for AMR control: accountability diluted with facilities having limited oversight after collection; transparency limited with PSPs treating details as proprietary; cost pressures may incentivize corner-cutting; AMR-specific considerations absent from contracts and monitoring.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.11 Resource and Capacity Constraints\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFinancial Resources:\u003c/strong\u003e All facilities reported inadequate budgets. Private facilities particularly struggled, with waste management fees representing significant operating costs, creating perverse incentives to minimize measured waste volume.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eInfrastructure Deficits:\u003c/strong\u003e Inadequate storage facilities lacking climate control; insufficient color-coded containers; limited transport equipment; erratic personal protective equipment supplies.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eHuman Resources:\u003c/strong\u003e Staff shortages affected waste management: suboptimal cleaner-to-bed ratios; infection control officers with competing responsibilities; vacant or under-qualified environmental health positions; limited training capacity.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTechnical Capacity:\u003c/strong\u003e Knowledge and skill gaps extended beyond frontline workers to management and oversight personnel, including administrators, infection control officers, and regulators.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4.12 Stakeholder Perspectives on AMR-Waste Linkages\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHealthcare Workers:\u003c/strong\u003e Clinical staff had higher AMR awareness as clinical problem but lower awareness of environmental dimensions: \u0026quot;We think about resistance when prescribing... We don\u0026apos;t usually think about waste management as part of the AMR problem.\u0026quot;\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWaste Management Personnel:\u003c/strong\u003e Cleaners had minimal AMR awareness generally and none regarding waste-AMR linkages: \u0026quot;I know about HIV and hepatitis from sharps... But antimicrobial resistance, I don\u0026apos;t know about that.\u0026quot;\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAdministrators and Policymakers:\u003c/strong\u003e Hospital administrators and LAWMA officials acknowledged AMR importance but hadn\u0026apos;t considered waste management as contributing factor, expressing openness to interventions but emphasizing resource constraints.\u003c/p\u003e"},{"header":"5. Discussion","content":"\u003cp\u003e\u003cstrong\u003e5.1 Medical Waste as AMR Vector in Lagos\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study provides compelling evidence that inadequate medical waste management in Lagos creates multiple pathways for AMR dissemination. The finding that only 61% correctly identify segregation procedures, combined with frequent mixing of pharmaceutical waste with general streams, creates conditions where antimicrobial containing materials receive inadequate treatment and enter environmental compartments. At approximately 215 kg/day across surveyed facilities and likely exceeding 100,000 kg/day across Lagos\u0026apos;s 500+ facilities, with pharmaceutical waste comprising 5-8% (suggesting 5,000-8,000 kg daily citywide), inadequate segregation and\u003c/p\u003e\n\u003cp\u003etreatment means substantial antimicrobial quantities enter the environment with active compounds intact, exerting selective pressure for resistance (Singh et al., 2021; Khan et al., 2021).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.2 Critical Control Point Failures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePoint of Generation: Inadequate segregation represents the most fundamental failure. Only 33.3% correctly identify pharmaceutical waste color-coding; observations showed routine mixing. This failure roots in insufficient training (particularly for cleaners with lowest knowledge), inadequate infrastructure (container stockouts), perverse incentives (minimizing measured volumes to reduce costs), and lack of AMR awareness.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eStorage Duration:\u003c/strong\u003e Storage routinely exceeding 24-48 hour limits, with actual durations of 5-10 days, creates extended periods for bacterial proliferation, horizontal gene transfer, and resistance amplification. In tropical Lagos conditions (27-32\u0026deg;C, high humidity) in unrefrigerated facilities, these periods provide ideal circumstances for AMR amplification before waste reaches treatment.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTreatment Adequacy:\u003c/strong\u003e Reliance on hydroclave for all medical waste raises AMR adequacy questions. While hydroclave effectively sterilizes biological materials (killing resistant bacteria), it doesn\u0026apos;t chemically degrade antimicrobial compounds that persist in treated waste and enter disposal sites (Giakoumakis et al., 2021; Kenny \u0026amp; Priyadarshini, 2021). Current treatment addresses only one AMR dimension (resistant bacteria) while failing another (antimicrobial selective pressure).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eFinal Disposal:\u003c/strong\u003e The opacity surrounding final disposal is most concerning. LAWMA\u0026apos;s statement that treated waste \u0026quot;goes through normal disposal channels\u0026quot; suggests disposal in Lagos\u0026apos;s municipal dumpsites where waste picking occurs and environmental controls are minimal. Even if biological hazards are eliminated, antimicrobial residues persisting in waste leach into soil and groundwater, contributing to sustained environmental contamination and selective pressure (Siddiqua et al., 2022).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.3 Vulnerable Populations and Environmental Justice\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFindings illuminate environmental justice dimensions. Waste handlers, predominantly low-income cleaners, experience greatest occupational exposure but receive least training (52.3% vs. 89-95% for professional staff), reflecting systematic marginalization. These workers face daily exposure through direct contact, needle sticks (23.8% reported), and aerosol inhalation, often with inadequate personal protective equipment. Waste pickers at disposal sites represent another vulnerable population, experiencing exposure without even limited protections afforded formal healthcare workers. These marginalized individuals scavenge for recyclables unaware of\u003c/p\u003e\n\u003cp\u003eAMR exposure (Cook \u0026amp; Velis, 2021; Schenck et al., 2019). Communities near waste storage and disposal sites experience environmental exposure through water contamination (leachate, runoff), soil contamination (spillage, leaks), air contamination (aerosols), and food chain contamination.\u003c/p\u003e\n\u003cp\u003eThis demonstrates AMR dissemination through medical waste exacerbates environmental inequities, adding another dimension to health disparities facing vulnerable populations (Pulido, 2017; Olaniyi et al., 2019).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.4 Policy and Governance Challenges\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNigeria\u0026apos;s National Healthcare Waste Management Plan lacks AMR-specific provisions, reflecting broader disconnect between waste management and AMR policy domains. This siloed approach means waste policies focus on infection prevention and occupational safety without environmental AMR implications, while AMR policies focus on clinical use and surveillance without waste pathways (Ezirim \u0026amp; Agbo, 2018). Institutional fragmentation compounds gaps. Responsibilities across Federal Ministry of Health, Federal Ministry of Environment, NESREA, state agencies, and local departments create coordination challenges, accountability diffusion, and oversight gaps (Ezeudu et al., 2022). Implementation deficits further undermine existing policies:\u003c/p\u003e\n\u003cp\u003eweak enforcement with minimal penalties; resource constraints limiting implementation and enforcement capacity; technical capacity gaps; and variable political will (Scholz, 2020; Lawless et al., 2020).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.5 Integrated Framework for AMR-Oriented Waste Management\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBased on findings, we propose an integrated framework comprising five interconnected components:\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eComponent 1 - Enhanced Segregation at Point of Generation:\u003c/strong\u003e Dedicated pharmaceutical waste containers in all areas with clear antimicrobial-specific markings; simplified color-coding with pharmaceutical waste distinctly identified; point-of-use decision aids helping correct categorization; regular segregation audits with staff feedback; integration into existing infection control systems.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eComponent 2 - Safe Storage and Transport:\u003c/strong\u003e Improved infrastructure with covered, secure facilities; more frequent collection (twice weekly minimum); cold storage/climate control for high-risk waste using low-cost options (shading, evaporative cooling); spill containment systems with impermeable flooring; dedicated enclosed transport.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eComponent 3 - AMR-Targeted Treatment:\u003c/strong\u003e Segregated treatment pathways with pharmaceutical waste receiving specialized treatment; enhanced technologies capable of degrading antimicrobial compounds (high-temperature incineration \u0026gt;850\u0026deg;C); treatment verification through periodic monitoring; technology assessment evaluating hydroclave adequacy for AMR control.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eComponent 4 - Environmental Monitoring:\u003c/strong\u003e Baseline environmental assessment characterizing antimicrobial contamination and resistant bacteria prevalence near facilities, storage sites, treatment facilities, and disposal sites; ongoing monitoring using sentinel antimicrobials, resistance genes, and resistant bacteria indicators; participatory approaches engaging communities and waste workers; data systems linking practices to environmental AMR\u003c/p\u003e\n\u003cp\u003eoutcomes.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eComponent 5 - Integrated Policy and Governance:\u003c/strong\u003e Policy integration incorporating AMR into waste management frameworks and vice versa; institutional coordination mechanisms addressing fragmentation; strengthened enforcement with increased penalties and inspection capacity; capacity building at all levels on AMR-waste linkages; sustainable financing mechanisms.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.6 Implementation Barriers and Enabling Strategies\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFinancial Constraints:\u003c/strong\u003e Enable through efficiency gains from proper segregation; external financing (donors, government, extended producer responsibility); incremental implementation prioritizing high-impact, low-cost interventions (segregation, training) before infrastructure-intensive improvements.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTechnical Capacity Gaps:\u003c/strong\u003e Enable through targeted training integrating AMR-waste content; mentorship and peer learning; simplified protocols and decision aids; partnerships with universities providing technical assistance.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eInstitutional Fragmentation:\u003c/strong\u003e Enable through high-level coordination mechanisms (inter-ministerial task forces); joint planning and implementation; shared accountability frameworks; integrated monitoring systems.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePolitical and Cultural Factors:\u003c/strong\u003e Enable through advocacy highlighting AMR-waste connections; community engagement raising awareness; identifying and supporting champions; alignment with existing priorities (infection prevention, occupational health, environmental protection).\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.7 Study Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study contributes: detailed documentation of medical waste-AMR linkages in major African megacity addressing significant evidence gap; integrated socio-ecological framework recognizing complex system requiring multilevel interventions; demonstration of mixed-methods value combining quantitative assessment with qualitative contextual exploration; identification of specific policy gaps with evidence-based recommendations; and illumination of environmental justice dimensions documenting vulnerable population exposure.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5.8 Limitations and Future Directions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eLimitations include purposive sampling limiting statistical generalizability; potential social desirability bias; resource constraints preventing environmental sampling for antimicrobial residues and resistant bacteria - a significant gap requiring future research; limited access to private operators preventing detailed documentation beyond facility handoff; and cross-sectional design without temporal variation assessment.\u003c/p\u003e\n\n\u003cp\u003eFuture research directions include: environmental monitoring studies directly measuring antimicrobial residues and resistant bacteria in wastewater, soil, water, and air; intervention research evaluating specific improvement effectiveness; health impact assessment linking environmental contamination to community health outcomes; economic analysis examining cost-benefit of improved approaches; comparative research across diverse settings; and social science research examining risk perceptions and behaviors.\u003c/p\u003e"},{"header":"6. Conclusion","content":"\u003cp\u003eThis study provides comprehensive documentation of critical intersections between medical waste management and antimicrobial resistance in Lagos, revealing systematic deficiencies creating multiple pathways for AMR dissemination through environmental contamination. Across seven diverse healthcare facilities, findings demonstrate that inadequate segregation (only 61% proper), prolonged storage (5\u0026ndash;10 days vs. recommended 24\u0026ndash;48 hours), insufficient treatment (hydroclave sterilizes but doesn't degrade antimicrobials), and opaque disposal combine to\u003c/p\u003e \u003cp\u003eenable antimicrobial residues and resistant bacteria to enter environmental compartments with minimal control.\u003c/p\u003e \u003cp\u003eThe magnitude is substantial: approximately 215 kg/day across surveyed facilities (translating to likely\u0026thinsp;\u0026gt;\u0026thinsp;100,000 kg/day citywide), with 5\u0026ndash;8% pharmaceutical waste including antimicrobials; only 33.3% correct identification of pharmaceutical waste protocols, resulting in routine mixing with general streams; storage in tropical conditions (27\u0026ndash;32\u0026deg;C) conducive to bacterial proliferation and gene transfer; treatment failing to degrade antimicrobial compounds that persist into disposal sites; and absent environmental monitoring leaving contamination levels unmeasured. These findings reveal medical waste as significant yet underrecognized AMR propagation vector in rapidly urbanizing African contexts. While clinical antimicrobial use receives considerable AMR discourse attention, this study demonstrates waste management failures create parallel pathways through which resistant bacteria and antimicrobial selective pressure disseminate in communities. Environmental AMR dimensions extend resistance development and transmission beyond healthcare settings into community environments where exposure occurs through contaminated water and soil, occupational contact, scavenging, and ecosystem-wide microbial impacts.\u003c/p\u003e \u003cp\u003eEnvironmental justice analysis reveals AMR dissemination through waste disproportionately impacts vulnerable populations. Waste handlers experience highest occupational exposure yet receive least training (52.3% vs. 89\u0026ndash;95% for professional staff). Communities near waste sites experience environmental exposure through water, soil, and air contamination. Waste pickers experience direct contact while earning subsistence livelihoods. These exposure distributions reflect and exacerbate existing health inequities, adding AMR risks to multiple environmental health burdens already borne by vulnerable populations.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003ePolicy analysis identifies critical gaps\u003c/strong\u003e \u003cp\u003eNigeria's National Healthcare Waste Management Plan lacks AMR-specific provisions; institutional fragmentation creates coordination challenges and accountability diffusion; weak enforcement fails to compel compliance; privatization through LAWMA/PSP improves some dimensions but creates transparency and accountability gaps particularly regarding AMR concerns.\u003c/p\u003e \u003c/p\u003e \u003cp\u003eThe proposed integrated framework offers evidence-based pathways through enhanced segregation with pharmaceutical waste specifically identified; safe storage and transport with reduced duration and environmental exposure; AMR-targeted treatment using technologies degrading antimicrobial compounds; environmental monitoring establishing baseline contamination and tracking effects; and integrated policy addressing fragmentation while incorporating AMR considerations into waste frameworks and waste considerations into AMR frameworks.\u003c/p\u003e \u003cp\u003eImplementation requires addressing financial constraints, technical capacity gaps, institutional fragmentation, and political prioritization through enabling strategies including external financing, capacity building partnerships, high-level coordination mechanisms, and advocacy elevating waste management within AMR discourse. Incremental approaches prioritizing high-impact, low-cost interventions (segregation, training) before infrastructure-intensive improvements (treatment technology upgrades) can enable progress within resource constraints while building toward comprehensive solutions.\u003c/p\u003e \u003cp\u003eThis research demonstrates that effective AMR control requires expanding traditional clinical focus (antimicrobial prescribing, infection prevention within healthcare facilities) to encompass environmental pathways through which resistance propagates in communities. Medical waste management represents a critical yet neglected component of comprehensive AMR responses. In rapidly urbanizing developing country contexts like Lagos - where healthcare systems are expanding, waste generation is increasing, and management infrastructure is inadequate \u0026ndash; addressing waste-AMR linkages is essential for protecting population health and environmental sustainability.\u003c/p\u003e \u003cp\u003eThe findings from Lagos have broader significance for many African and global cities experiencing similar convergence: rapid urbanization, expanding healthcare access, increasing antimicrobial use, inadequate waste infrastructure, and vulnerable populations at risk. While specific contexts vary, fundamental dynamics documented here - inadequate segregation, prolonged storage, insufficient treatment, environmental contamination, vulnerable\u003c/p\u003e \u003cp\u003epopulation exposure - likely occur across diverse settings. The integrated framework offers adaptable principles for addressing waste-AMR linkages in resource-constrained contexts, requiring contextualization but providing strategic direction.\u003c/p\u003e \u003cp\u003eUltimately, this study reinforces that AMR is not merely a clinical problem amenable to clinical solutions alone, but rather a complex socio-ecological challenge requiring coordinated interventions across healthcare, environment, governance, and community domains. Medical waste management, positioned at the intersection of these domains, offers an intervention point where relatively feasible improvements can yield substantial AMR control benefits while\u003c/p\u003e \u003cp\u003esimultaneously addressing infection prevention, occupational health, environmental protection, and health equity objectives. Realizing this potential requires political will, resource mobilization, technical capacity building, and sustained commitment - challenges certainly, but not insurmountable ones given the stakes for public health in an era of escalating antimicrobial resistance.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eEthical approval for this study was obtained from the \u003cstrong\u003eLagos Waste Management Authority (LAWMA)\u003c/strong\u003e. All participants provided informed consent prior to participation. This study was conducted in accordance with the principles of the \u003cstrong\u003eDeclaration of Helsinki\u003c/strong\u003e.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eNot applicable (Participants were not identifiable and no personal data was published.)\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eThe authors declare \u003cstrong\u003eno competing interests\u003c/strong\u003e.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eFunding Declaration\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eThis research received \u003cstrong\u003eno external funding\u003c/strong\u003e. All aspects of the study, data collection, analysis, and manuscript preparation were conducted without financial support from any public, commercial, or not-for-profit funding agency.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eClinical Trial Registration\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eClinical trial number: \u003cstrong\u003eNot applicable.\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;This study did not involve any clinical trial or clinical intervention requiring registration.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eEthics Declaration\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eAll participants provided informed consent prior to participation.\u003cbr\u003e\u0026nbsp;No animals, clinical interventions, or patient-identifying information were involved.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eThe data supporting the findings of this study\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eare \u003cstrong\u003eavailable from the corresponding author upon request.\u003c/strong\u003e Due to confidentiality agreements with participating healthcare facilities, raw data cannot be made publicly accessible.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003e\u003cstrong\u003eConceptualization:\u003c/strong\u003e Yusuf, Gbolahan Afeez\u003cbr\u003e\u003cstrong\u003eMethodology:\u003c/strong\u003e Yusuf, Gbolahan Afeez; Olaleye, Oluremi Nurudeen\u003cbr\u003e\u003cstrong\u003eData Collection:\u003c/strong\u003e Yusuf, Gbolahan Afeez\u003cbr\u003e\u003cstrong\u003eAnalysis \u0026amp; Interpretation:\u003c/strong\u003e Yusuf, Gbolahan Afeez; Olaleye, Oluremi Nurudeen\u003cbr\u003e\u003cstrong\u003eWriting - Original Draft:\u003c/strong\u003e Yusuf, Gbolahan Afeez\u0026nbsp;\u003cbr\u003e\u003cstrong\u003eWriting - Review \u0026amp; Editing:\u003c/strong\u003e Yusuf, Gbolahan Afeez; Olaleye, Oluremi Nurudeen\u003cbr\u003e\u0026nbsp;All authors reviewed and approved the final manuscript.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/h2\u003e\n\u003ch2\u003e\u003cstrong\u003eConflict of Interest Declaration\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eThe authors declare \u003cstrong\u003eno competing financial or personal interests\u003c/strong\u003e that could have influenced the work reported in this paper.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eAdetola, I. 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Healthcare waste management in Nigeria: A review. Recycling, 7(87), 1-16.\u003c/li\u003e\n \u003cli\u003eFerronato, N., \u0026amp; Vincenzo, T. (2019). Waste mismanagement in developing countries: A review of global issues. International Journal of Environmental Research and Public Health, 16(6), 1060.\u003c/li\u003e\n \u003cli\u003eGiakoumakis, G., Politi, D., \u0026amp; Sidiras, D. (2021). Medical waste treatment technologies for energy, fuels, and materials production: A review. Energies, 14(23), 8065.\u003c/li\u003e\n \u003cli\u003eHantoko, D., Li, X., Pariatamby, A., Yoshikawa, K., Horttanainen, M., \u0026amp; Yan, M. (2021). Challenges and practices on waste management and disposal during COVID-19 pandemic. Journal of Environmental Management, 286, 112140.\u003c/li\u003e\n \u003cli\u003eHarrison, R. L., Reilly, T. M., \u0026amp; Creswell, J. W. (2020). Methodological rigor in mixed methods: An application in management studies. Journal of Mixed Methods Research, 14(4), 473-495.\u003c/li\u003e\n \u003cli\u003eHassan, E. R., Zada, E., Gintamo, B., Mekuria, Z. N., \u0026amp; Gizaw, Z. (2021). Planning for disposal of COVID-19 pandemic wastes in developing countries: A review of current challenges. Environmental Science and Pollution Research, 193(9), 592-603.\u003c/li\u003e\n \u003cli\u003eJones, J. A., \u0026amp; Donmoyer, R. (2021). Improving the trustworthiness/validity of interview data in qualitative nonprofit sector research. Nonprofit and Voluntary Sector Quarterly, 50(4), 889-904.\u003c/li\u003e\n \u003cli\u003eKenny, C., \u0026amp; Priyadarshini, A. (2021). Review of current healthcare waste management methods and their effect on global health. Healthcare, 9(3), 284.\u003c/li\u003e\n \u003cli\u003eKhalid, S., Haq, N., Sabiha, Z., Latif, A., Khan, M. A., Iqbal, J., \u0026amp; Yousaf, N. (2021). 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International Journal of Preventive Medicine, 12, 20.\u003c/li\u003e\n \u003cli\u003eSangkham, S. (2020). Face mask and medical waste disposal during the novel COVID-19 pandemic in Asia. Case Studies in Chemical and Environmental Engineering, 2, 100052.\u003c/li\u003e\n \u003cli\u003eSchenck, C. J., Blaauw, P. F., Viljoen, J., \u0026amp; Swart, E. C. (2019). Exploring the potential health risks faced by waste pickers on landfills in South Africa: A socio-ecological perspective. International Journal of Environmental Research and Public Health, 16(2059).\u003c/li\u003e\n \u003cli\u003eScholz, N. (2020). Addressing health inequalities in the European Union. European Parliamentary Research Service.\u003c/li\u003e\n \u003cli\u003eSibanda, P. (2019). Health and socioeconomic analysis of waste picking activities in Durban [Master\u0026apos;s thesis, University of KwaZulu-Natal].\u003c/li\u003e\n \u003cli\u003eSiddiqua, A., Hahladakis, J. N., \u0026amp; Al-Attiya, W. A. (2022). An overview of the environmental pollution and health effects associated with waste landfilling and open dumping. Environmental Science and Pollution Research, 29,\u0026nbsp;58514\u0026ndash;58536.\u003c/li\u003e\n \u003cli\u003eSingh, N., Ogunseitan, O. A., \u0026amp; Tang, Y. (2021). Medical waste: Current challenges and future opportunities for sustainable management. Critical Reviews in Environmental Science and Technology, 52(11), 1915-1945.\u003c/li\u003e\n \u003cli\u003eWorld Health Organization. (2021). Global progress report on HIV, viral hepatitis and sexually transmitted infections, 2021. WHO\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"bmc-public-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pubh","sideBox":"Learn more about [BMC Public Health](http://bmcpublichealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pubh/default.aspx","title":"BMC Public Health","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"antimicrobial resistance, medical waste management, environmental contamination, public health, Lagos Nigeria, pharmaceutical waste, healthcare facilities","lastPublishedDoi":"10.21203/rs.3.rs-8083114/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8083114/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAntimicrobial resistance (AMR) represents a critical global health threat, with medical waste management serving as an underexplored vector for resistance gene dissemination. This study examines the relationship between inadequate medical waste management and AMR propagation in Lagos, Nigeria's megacity of over 20\u0026nbsp;million inhabitants.\u003c/p\u003e \u003cp\u003eThrough mixed-methods assessment of seven healthcare facilities, we documented significant deficiencies: only 61% proper waste segregation at source, 33.3% correct identification of pharmaceutical waste protocols, storage durations of 5\u0026ndash;10 days (versus recommended 24\u0026ndash;48 hours), and widespread mixing of antimicrobial-containing waste with general streams. Facilities generated 215.56 kg/day of medical waste (0.181 kg/bed/day average), with pharmaceutical waste comprising 5\u0026ndash;8% yet receiving no specialized treatment beyond standard hydroclave sterilization - inadequate for degrading antimicrobial compounds. Analysis reveals multiple environmental contamination pathways: wastewater discharge, storage site leachate, transport spillage, and inadequate final disposal exposing waste handlers, communities, and environmental matrices to antimicrobial residues and resistant bacteria.\u003c/p\u003e \u003cp\u003eNigeria's fragmented policy framework, characterized by weak enforcement and absent AMR-specific provisions, exacerbates these challenges. Cost constraints, limited technical capacity, and insufficient training emerged as primary implementation barriers. This study proposes an integrated framework combining enhanced segregation, AMR-targeted treatment technologies, environmental monitoring, strengthened regulatory enforcement with AMR provisions, and community-based approaches. Findings have significant implications for public health policy in\u003c/p\u003e \u003cp\u003eresource-constrained urban settings where inadequate waste infrastructure creates conditions for AMR amplification and dissemination through environmental pathways.\u003c/p\u003e","manuscriptTitle":"Antimicrobial Resistance Spread Through Medical Waste: Environmental Contamination and Public Health Implications in Urban Nigeria","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-18 09:58:34","doi":"10.21203/rs.3.rs-8083114/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-16T09:47:30+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"45661205527784916995737350222923250186","date":"2026-02-13T18:06:57+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-13T11:44:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"53780889286203768428680288883076227470","date":"2026-02-13T10:54:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"306933641032789004611806365838712766038","date":"2026-02-12T15:26:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"96831525753549473928339720550101867879","date":"2026-02-12T15:02:54+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-07T20:17:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"228268330052697155676403705558087004721","date":"2026-01-13T12:50:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"136951454824059463261051814142610411631","date":"2026-01-09T08:36:44+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-31T01:12:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"308017539206034493907326527690869988005","date":"2025-12-17T18:16:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"281894529074566576858688006551937427990","date":"2025-12-17T16:16:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"261690919818879797709359662894410820443","date":"2025-12-15T05:14:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"295591791901553851458011673494770163157","date":"2025-12-13T23:15:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"297604865541201346354333031703807123183","date":"2025-12-12T16:22:12+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-12T16:09:01+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-11T08:25:06+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-02T10:29:25+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-02T09:47:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Public Health","date":"2025-12-02T08:56:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-public-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pubh","sideBox":"Learn more about [BMC Public Health](http://bmcpublichealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pubh/default.aspx","title":"BMC Public Health","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7e6d580b-b0ab-4af0-add7-3f10ec0a786a","owner":[],"postedDate":"December 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-20T13:23:20+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-18 09:58:34","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8083114","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8083114","identity":"rs-8083114","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}