TitleThe influence of obesity on blood mercury levels for U.S. non-pregnant adults and children: NHANES 2007-2010.
Publication TypeJournal Article
Year of Publication2015
AuthorsRothenberg, SE, Korrick, SA, Fayad, R
JournalEnviron Res
Date Published04/2015
KeywordsAdolescent, Adult, Aged, Body Mass Index, Child, Child, Preschool, Cross-Sectional Studies, Environmental Exposure, Female, Humans, Male, Mercury, Methylmercury Compounds, Middle Aged, Nutrition Surveys, Obesity, Seafood, United States, Young Adult

BACKGROUND: In animal studies obesity is associated with higher blood and tissue mercury concentrations; however human studies are lacking. Although the mechanism underlying this association is uncertain, obesity may alter the metabolism and distribution of methylmercury.

OBJECTIVES: We determined whether obesity influenced blood mercury levels, the majority of which was methylmercury, for U.S. non-pregnant adults (≥20 years) and children (2-19 years) after controlling for methylmercury intake through fish and shellfish consumption, and other confounders.

METHODS: We completed secondary data analysis of the National Health and Nutrition Examination Survey (NHANES) (2007-2010) for participants who consumed fish/shellfish within 24h of blood collection for mercury analysis. Weighted least squares regression models related blood mercury levels (the dependent variable) to methylmercury exposure (μg) from fish consumed in the previous 24h, body mass index (BMI) (for adults), BMI z-scores (for children), and other confounders.

RESULTS: In adjusted models, blood mercury levels were inversely correlated with BMI for adults [β, 95% confidence interval (CI)=-0.54 (-0.90, -0.18)]. For children, blood mercury levels were inversely correlated with BMI z-scores but the trend was not significant [β (95% CI)=-0.016 (-0.066, 0.035)]. When obese adults or children were compared with those who were overweight/normal weight, blood mercury averaged 22% lower for obese adults (95% CI: -33%, -8.2%), while blood mercury did not differ significantly for obese children [β (95% CI)=-1.7% (-31%, +39%)].

CONCLUSIONS: After adjusting for the main, if not exclusive, exogenous source of methylmercury exposure (through fish/shellfish intake) and other confounders, our results support potential changes in the metabolism, distribution or excretion of methylmercury with increasing BMI (for adults).

Alternate JournalEnviron. Res.
PubMed ID25721244
PubMed Central IDPMC4385493
Grant ListP01ES022832 / ES / NIEHS NIH HHS / United States
R15 ES022409 / ES / NIEHS NIH HHS / United States
R15ES022409 / ES / NIEHS NIH HHS / United States
L30 ES023165 / ES / NIEHS NIH HHS / United States
L30ES023165-01 / ES / NIEHS NIH HHS / United States
P01 ES022848 / ES / NIEHS NIH HHS / United States
P01 ES022832 / ES / NIEHS NIH HHS / United States
R01ES014864 / ES / NIEHS NIH HHS / United States
R01 ES014864 / ES / NIEHS NIH HHS / United States