Intellectual Coefficient and Environmental Exposure to Air Pollutants in Mexican Children from Urban Area

Abstract

INTRODUCTION: Ecatepec County in Mexico City Metropolitan Area is highly industrialized with high traffic flow and considered as one of the most polluted regarding particulate matter (PM); however there are no reports about other air pollutants. OBJECTIVE: We evaluated the exposure to polycyclic aromatic hydrocarbons (PAHs), benzene, PM10 and PM2.5 and their association with the decrease in the Intellectual Coefficient (IQ) in school-aged children from Ecatepec County. METHODS: We conducted a cross sectional study in children aged 7 to 10 years from 3 different areas of the municipality of Ecatepec. PM10 and PM2.5 air concentrations were estimated by gravimetry by local monitoring in the schools; urinary concentrations of 1- hydroxypyrene (1-OHP) and t,t-muconic acid (t,t-MA) as indicators of PAH and benzene exposure, respectively were determined by HPLC. The IQ was evaluated with the Wechsler Scale for Children IV. RESULTS: A total of 244 schoolchildren participated. PM10 and PM2.5 concentrations were above national standards several days during the study. Fifteen percent of children had t,t-MA levels higher than the limit for workers (500 µg/g creatinine). The median value of 1-OHP was 0.018 µmol/mol creatinine, and preliminary results from multivariate analyses showed that PAH exposure is associated with decrement IQ. CONCLUSION: We found a complex scenario of air contaminants in Ecatepec County, affecting the development intellectual of school-aged children (Supported by CONACYT- México Grant #106034).