Increased urinary arsenic concentration in newly diagnosed type 2 diabetes mellitus: a gender-independent, smoking-dependent exposure biomarker in older adults in Tehran.

Arsenic is ranked in the top ten environmental toxicants but its impact on type 2 diabetes mellitus (T2DM) and its association with other human health effects is contradictory. We aimed in this study to compare the urinary arsenic concentration (u As) in older age adults (> 40 years) and their T2DM subgroup in an age and gender-matched case control study to find the association of u As with, diet, oxidative stress, smoking, anthropometric factors, and lifestyle in our study participants. Face-to-face interviews based on structured questionnaires were conducted on 200 female and male volunteers (100 cases and 100 control). Considering the exclusion criteria, u As concentration and serum biomarkers of oxidative stress (malondialdehyde, superoxide dismutase, catalase) of 30 newly diagnosed T2DM and 30 control were determined by ICP-mass analysis and ELISA reader respectively. Despite the similarities in sociodemographic, diet, and lifestyle factors in males and females and their T2DM subgroups, a 4 times difference in u As levels between T2DM (93.7 ng/L (32)) and their healthy counterparts (23.7 ng/L (2.3)) without meaningful associations with gender, age, BMI, diet, and lifestyle was observed. Mean u As concentration in total population of smokers was significantly higher than non-smokers ((119 ng/L vs. 22.5 ng/L (p = 0.03)) and oxidative stress markers were not significantly higher in T2DM smokers than non-smokers. Chronic arsenic exposure through smoking could be contributed to the incidence of T2DM in older age adults. Oxidative stress markers were not significantly increased in smoker subgroup compared with non-smokers but except smoking pattern, other variables did not affect u As concentration. Precautionary measure to reduce the exposure of people with this element is recommended to prevent the arsenic-induced T2DM in human populations.