Article

Blood mercury concentrations in pregnant and nonpregnant women in the United States: National Health and Nutrition Examination Survey 1999-2006

National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
American journal of obstetrics and gynecology (Impact Factor: 4.7). 11/2013; 210(4). DOI: 10.1016/j.ajog.2013.10.884
Source: PubMed

ABSTRACT

Prenatal exposure to methylmercury is associated with adverse neurological development in children. We examined total blood mercury (BHg) concentrations and predictors of higher BHg concentrations in pregnant and non-pregnant women.
We analyzed data from 1,183 pregnant and 5,587 non-pregnant women aged 16-49 years from the 1999-2006 National Health and Nutrition Examination Survey (NHANES). We estimated geometric mean BHg concentrations and characteristics associated with higher mercury concentrations (≥3.5 μg/L) in crude and adjusted linear and logistic regression models.
After adjusting for age and race/ethnicity, geometric mean BHg concentrations were clinically similar but significantly lower for pregnant (0.81 μg/L, 95% confidence interval [CI]: 0.71, 0.91) and non-pregnant women of childbearing age (0.93 μg/L, 95% CI: 0.87, 0.99); 94% of pregnant and 89% of non-pregnant women had BHg concentrations below 3.5 μg/L. The most significant predictor of higher BHg concentrations for both pregnant and non-pregnant women was any seafood consumption vs. no consumption in the last 30 days (Odds ratio [OR]: 18.7, 95% CI: 4.9, 71.1; OR: 15.5, 95% CI: 7.5, 32.1, respectively). Other characteristics associated with ≥3.5 μg/L BHg concentrations were older age (35+ years), higher education (greater than high school), and higher family income to poverty ratio (3.501+) for both pregnant and non-pregnant women.
Pregnancy status was not strongly associated with BHg concentrations in women of childbearing age and BHg concentrations above the 3.5 μg/L cut were uncommon.

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Available from: Hilda Razzaghi, Feb 19, 2015
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