Elevated Cardiometabolic Risk by Chronic Inorganic Arsenic Exposure in Chihuahua, Mexico.

Abstract

The present cross-sectional study examined associations between inorganic arsenic (iAs) exposure and cardiometabolic (CM) risk factors in a cohort of adult Chihuahua residents (n=933, ?18year old) with a minimum of 5-year uninterrupted residency in the study area were recruited between 2008 and 2012. The concentrations of As in drinking water ranged from 0.05 - 419.8 µg As/L with 84% and 42% of samples exceeding 10 µg As/L and 50 µg As/L, respectively. All subjects had detectable levels of As in urine. The concentration of total speciated As [iAs + methylarsenic (MAs) + dimethylarsenic (DMAs)] ranged from 0.52 to 375.2 µg/L. DMAs was the major urinary metabolite representing on average 75.7% of total speciated As, followed by MAs (14.5%) and iAs (9.8%). Results show that subjects in the highest exposure tertile trough drinking water (58.3 - 419.8 µg As/L) had higher levels of total cholesterol in plasma and were more likely to have dysglycemia (OR 1.60, 95%CI 1.09-2.32), hypertriglyceridemia (OR 1.53, 95%CI 1.07 - 2.20), and high blood pressure (OR 1.57, 95%CI 1.05 - 2.35) than subjects in the lowest exposure tertile (?38.5 µg As/L). Obesity may play a critical role in the associations between iAs exposure and CM risk. In addition, we found statistically significant positive associations of high urinary DMAs/MAs ratio with dysglycemia, hypertriglyceridemia, and high blood pressure. Thus, it is possible that an increased capacity to convert iAs to DMAs, may be a risk factor for CM disease in individuals chronically exposed to iAs. Prospective studies are needed to examine causality of the associations of CM risk with iAs exposure and to determine if iAs metabolism can modify this risk.