Is there any association between urinary phthalate metabolites and type 1 diabetes mellitus?

This study aims to investigate the association between some phthalate metabolites and type 1 diabetes mellitus (T1DM) in children. This case-control study was conducted in 2019–2020 in Isfahan, Iran. Participants consisted of 150 newly diagnosed cases of T1DM children and an equal number of age- and sex-matched healthy controls. Urinary phthalate metabolites (mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), monobenzyl phthalate (MBzP) and Monobutyl phthalate (MBP)) were measured and compared between the two groups. The association between urinary concentrations of phthalate metabolites and T1DM was determined after adjusting for age, sex, parental education, and duration of breastfeeding, and dietary patterns. Overall, 294 children (147 in each group) with a mean age of 8.5(3.7) years completed the study. The mean urinary concentration of phthalate metabolites in diabetic patients were significantly higher than controls [35(0.09–134) vs. 28.9(0.07-95) for MBP, 38.8(0.21-75) vs. 18.9(6.7–46.4) for MBzP, 263(105–603) vs. 90(44.5–237) for MEOHP, 1034(385–1884) vs. 514(188–1447) for MEHHP, P < 0.05 for all metabolites].High levels of urinary MEOHP significantly increased the risk of T1DM; OR (95% CI): 10.1(2.9–34.3).Our study indicated that the urine concentration of phthalate metabolites is significantly higher in T1DM patients and a significant association was found between MEOHP and T1DM.Our findings could be used as a baseline study for identifying the sources of the metabolites and introducing them to health policymakers as well as researchers to plan further studies for better understanding the role of different endocrine disruptor chemicals in the pathogenesis of T1DM.