The association between seafood consumption and blood mercury levels in adults age 20 years and up, 2007–2010

Abstract

BackgroundSeafood is a dietary source of mercury, a neurotoxin with adverse health consequences. No previous studies have examined associations between seafood consumption and blood mercury in the entire US adult population.ObjectiveTo determine the association between seafood consumption and blood mercury levels in US adults, using the most recent national data.DesignAdults, ages 20 years and older, who participated in the 2007–2010 National Health and Nutrition Examination Survey. Frequency of fish and/or shellfish (seafood) consumption was determined using a limited food frequency questionnaire over the past thirty days. Geometric mean blood mercury levels for quartiles of seafood consumption were calculated overall and by sex. Trends in mean mercury levels by quartile of seafood consumption were tested using linear trend tests.ResultsThere was a positive linear trend in blood mercury as seafood consumption increased (p<.001 for all trends). Geometric mean blood mercury was 0.5 ug/L among the lowest consumers of seafood compared to 2.1 ug/L among the highest consumers. Trends for men and women separately were also significant (p<.001).ConclusionIn the US adult population blood mercury levels are highest among those who consume the largest amounts of seafood.