Urinary concentrations of 2,5-dichlorophenol and diabetes in US adults

Para-dichlorobenzene (p-dcb) products are widely used in the home and public buildings, leading to exposure to this chemical in indoor environments. in this study, we explored potential relationships between p-dcb exposure and diabetes in us adults by analyzing a nationally representative subsample of 3063 adult participants aged 20–79 years randomly selected for measurement of urinary concentrations of 2,5-dichlorophenol (2,5-dcp), the major metabolite of p-dcb, in the 2007–2010 national health and nutrition examination survey. median urinary 2,5-dcp concentration was 7.0 μg/l (interquartile range: 2.1–29.9). of the participants, 560 (13.6%) were diabetic. a dose-dependent increase in the prevalence of diabetes was observed in the study participants across quartiles of urinary 2,5-dcp (p-trend<0.0001). after adjusting for potential confounders, individuals in the highest quartile of urinary 2,5-dcp had an increased odds of diabetes (or=1.59 (95% ci: 1.06, 2.40)) compared with individuals with the lowest quartile. the highest quartile of urinary 2,5-dcp was also positively associated with insulin resistance (adjusted β=0.75; 95% ci: 0.27, 1.24). this study demonstrated a potential association between exposure to p-dcb, measured as urinary concentrations of 2,5-dcp, and diabetes in us adults. additional epidemiologic and mechanistic studies would further explore these interactions.