Elevated Blood Mercury Leveis in Adult Avid Seafood Consumers

摘要

Background: Mercury (Hg) is a known neurotoxicant but risk at low levels of exposure is uncertain, particularly among the adult population. The most common source of exposure is in the form of methylmercury from predatory fish. Debate, spearheaded by the fishing industry, continues to surround the influence of seafood consumption on elevated blood mercury levels and related effects. Aims: Investigate prevalence of elevated Hg exposure among adult avid seafood consumers, and how that relates to seafood consumption patterns to inform risk communication efforts. Methods: The cohort of seafood consumers (N=290) was recruited from the coastal population of Long Island, New York. Participants completed a detailed food frequency questionnaire and provided blood which was analyzed for Hg at the RTI Trace Inorganics Laboratory and omega-3 fatty acids at the Guelph Lipid Analytics Laboratory. Statistical analyses included hierarchical cluster analysis to group fish consumers, and linear regression to quantify associations between consumption patterns, Hg, and omega-3 fatty acids. Results: In total, 41% of the participants had blood Hg above the reference dose (RfD=5.8 μg/L), with 90th %ile =17.8 μg/L, max=51.0 μg/L, and geometric mean=4.42 μg/L. Among females of child bearing age, 28% were above the RfD. The dominant fish types consumed were salmon, tuna, and shrimp; 45% ate salmon, shrimp, and tuna, each, at least 2-3 times/month. Consumers also ate many other types of seafood at lower frequency. In regression analyses adjusted for different types of seafood consumption, mercury was associated with weekly tuna steak intake, and monthly swordfish intake. Omega-3s were associated with weekly salmon intake. Conclusions: These findings identify an at-risk population of avid seafood consumers that could benefit from information on how to enjoy seafood while making low-mercury seafood choices. Future work will shed light on risks and benefits among avid seafood consumers.