Maternal Pesticide Exposure and Oral Clefts: an Exploratory Study

Objectives: The purpose of this study was to explore the relation between potential sources of maternal exposure to pesticides during conception and pregnancy and oral clefts in offspring. Methods: Data were obtained from a case-control study, 120 cases and 240 controls (neighbors of the cases); belonging to 82 communities with high prevalence of oral clefts in the State of Mexico. Information of multiple exposure sources and potential confounding variables was obtained from an interview. Sixty seven water samples and twenty four environmental samples were taken in the nearby domiciles to cultivation fields and in those which store pesticides, samples were studied by gas and liquid chromatography. Odds ratios and 95% confidence intervals (ORs) were estimated by univariate and multivariate analysis. Results: Carbamates and organophosphates concentrations were almost null and void, low concentrations of organochlorides: metolachlor p=.027 and metribuzin p=.000, hexachlorocyclopentadiene, p= .001 was detected: with interval concentrations of 0.0272 μg/mL to 0.0745 μg/mL in water, being greater in environmental samples 0.03138 μg/mL and 0.21924 μg/mL. Significant associations were observed between: simazine/abortions p= .000, and abortions threat p=.047, home stored: metolachlor p= .016, OR 1.297 (CI.641-2.622); mothers contact with simazine p=.010 and metolachlor p= .005 RO 1.593 (CI .761-3.333); dinking or cooking water stored in containers without hermetical close: metolachlor p= .016, hexachlorocyclopentadiene p= .029, simazine p=.023, metribuzin p=.000; residence close to fumigated crops p= .017, OR 1.116 (CI.706-1.762); offspring of relatives with the same occupation living in the same area X2 p=.034, OR 2.091 (CI.845-5.171). Oral clefts and reported use of pesticides did not show any significant association, however ORs suggested increased risk with metolachlor OR 1.000 (CI 95%. 463-2.159) Carbamates 1.000 (CI 95% .533-1.876) simazine OR 1.000 (CI 95%.695-1.439) and hexachlorocyclopentadiene, 1.063 (CI 95% .689-1.639). Conclusion: The results of this study suggest pesticide exposure could increase the risk of oral clefts, cholinesterase activity must be investigated in women who reported potential exposure to pesticides.