Docosahexaenoic Acid Effect on Prenatal Exposure to Arsenic and Atopic Dermatitis in Mexican Preschoolers.

Childhood atopic dermatitis (AD) is a chronic and recurrent health problem that involves multiple factors, particularly immunological and environmental. We evaluated the impact of docosahexaenoic acid (DHA) supplementation on prenatal arsenic exposure on the risk of atopic dermatitis in preschool children as part of the POSGRAD (Prenatal Omega-3 fatty acid Supplements, GRowth, And Development) clinical trial study in the city of Morelos, Mexico. Our study population included 300 healthy mother-child pairs. Of these, 146 were in the placebo group and 154 in the supplement group. Information on family history, health, and other variables was obtained through standardized questionnaires used during follow-up. Prenatal exposure to arsenic concentrations, which appear in maternal urine, was measured by inductively coupled plasma optical emission spectrometry. To assess the effect of prenatal arsenic exposure on AD risk, we ran a generalized estimating equation model for longitudinal data, adjusting for potential confounders, and testing for interaction by omega-3 fatty acid supplementation during pregnancy. The mean and SD (standard deviation) of arsenic concentration during pregnancy was 0.06 mg/L, SD (0.04 mg/L). We found a marginally significant association between prenatal arsenic exposure and AD (OR = 1.12, 95% CI: 0.99, 1.26); however, DHA supplementation during pregnancy modified the effect of arsenic on AD risk (p < 0.05). The results of this study strengthen the evidence that arsenic exposure during pregnancy increases the risk of atopic dermatitis early in life. However, supplementation with omega-e fatty acids during pregnancy could modify this association.

Fluoride Exposure through Different Drinking Water Sources in a Contaminated Basin in Guanajuato, Mexico: A Deterministic Human Health Risk Assessment.

Water fluoride levels above the World Health Organization's guideline (1.5 mg/L), common in overexploited aquifers, represent a health hazard. Our objective was to assess the health risks posed by exposure to fluoride in different drinking water sources in a contaminated basin in Mexico. Fluoride was measured in mutual drinking water sources and in the urine of 39 children and women. Risks were estimated through hazard quotient (HQ) by drinking water source. Dental fluorosis was assessed in the children. Mean fluoride water concentrations (mg/L) were: well, 4.2; waterhole, 2.7; bottled, 2.1; rainwater, 0.4. The mean urinary fluoride concentrations (specific gravity adjusted) were 2.1 mg/L and 3.2 mg/L in children and women, respectively. Our multiple linear regression model showed children's urinary fluoride concentrations increased 0.96 mg/L for every 1 mg/L increase in water fluoride (p < 0.001). Dental fluorosis was diagnosed in 82% of the children, and their HQ according to drinking water source was: well, 1.5; waterhole, 1.1; bottled, 0.8; harvested rainwater, 0.3. The pervasive dental fluorosis indicates a toxic past fluoride exposure; urinary fluoride levels and HQs indicate high exposure and current health risks for most children. Drinking harvested rainwater will likely prevent most of the local fluoride exposure.