Mercury Exposure from Domestic and Imported Estuarine and Marine Fish in the U.S. Seafood Market

Abstract

BackgroundMethylmercury exposure causes a variety of adverse effects on human health. Per capita estimates of mercury exposure are critical for risk assessments and for developing effective risk management strategies.ObjectiveThis study investigated the impact of natural stochasticity in mercury concentrations among fish and shellfish harvested from the Atlantic Ocean, Pacific Ocean, and foreign shores on estimated mercury exposures.MethodsMercury concentrations and seafood consumption are grouped by supply region (Atlantic Ocean, Pacific Ocean, and foreign shores). Distributions of intakes from this study are compared with values obtained using national FDA (Food and Drug Administration) mercury survey data to assess the significance of geographic variability in mercury concentrations on exposure estimates.ResultsPer capita mercury intake rates calculated using FDA mercury data differ significantly from those based on mercury concentration data for each supply area and intakes calculated for the 90th percentile of mercury concentrations.ConclusionsDifferences in reported mercury concentrations can significantly affect per capita mercury intake estimates, pointing to the importance of spatially refined mercury concentration data. This analysis shows that national exposure estimates are most influenced by reported concentrations in imported tuna, swordfish, and shrimp; Pacific pollock; and Atlantic crabs. Collecting additional mercury concentration data for these seafood categories would improve the accuracy of national exposure estimates.

Regional variation in mercury and stable isotopes of red snapper (Lutjanus campechanus) in the northern gulf of Mexico, USA

“…As a result, nearly 65% of the U.S. coastline is under an Hg advisory, including the entire Gulf of Mexico [1]. Despite the importance of marine fish in human diets and high levels of Hg observed by monitoring agencies [2], much of the research that has been conducted on aquatic Hg cycling has occurred in freshwater ecosystems [3]. Studies of Hg bioaccumulation in marine ecosystems often examine fish collected from limited geographic areas [4][5][6][7].…”

Transformations of mercury in the marine water column

“…Estimates of fish sources suggest that up to 90% of fish consumed in the US are from marine and estuarine environments [Sunderland, 2007]. As a result, understanding the factors that control…”

“…Despite the importance of marine fish for human consumption [Sunderland, 2007] and the potential health risks posed by exposure to high concentrations of mercury (Hg) , little is known about the potential for Hg methylation in the marine water column. This is important to explore as monomethlymercury (MMHg) is the chemical species of…”

“…From the addition of bulk organic matter as well as individual compounds important for methylation in anaerobic bacteria, we observe no simple limitation of Hg methylation in marine waters but highly dynamic conversion of Hg between methylated and inorganic species. List of Tables 13 Chapter 1: Introduction 15Chapter 2: Determination of monomethylmercury from seawater with ascorbic acidassisted direct ethylation Despite these guidelines, it is estimated that 0.6-11% of US women ages 16-49 have blood mercury (Hg) levels above the recommended limit for safe exposure [Mahaffey et al, 2004].Estimates of fish sources suggest that up to 90% of fish consumed in the US are from marine and estuarine environments [Sunderland, 2007]. As a result, understanding the factors that control…”

Mercury in coastal watersheds along the Chinese Northern Bohai and Yellow Seas

“…To develop pollution control strategies and systematic approaches for better management of Hg from inland rivers to the sea, information on input, transport, accumulation and geochemical distribution of Hg within coastal watersheds along the CNBYS is needed. In aquatic systems, inorganic Hg is converted to MeHg, which is the form of Hg that accumulates in aquatic food webs [31]. To better assess the potential hazard of Hg in aquatic ecosystems, the [MeHg] in biota were analyzed; however, the [MeHg] in waters and sediments was not measured in this study.…”