Bluefin tuna reveal global patterns of mercury pollution and bioavailability in the world's oceans
Journal
Proceedings of the National Academy of Sciences of the United States of America
Journal Volume
118
Journal Issue
38
Date Issued
2021
Author(s)
Abstract
Bluefin tuna (BFT), highly prized among consumers, accumulate high levels of mercury (Hg) as neurotoxic methylmercury (MeHg). However, how Hg bioaccumulation varies among globally distributed BFT populations is not understood. Here, we show mercury accumulation rates (MARs) in BFT are highest in the Mediterranean Sea and decrease as North Pacific Ocean > Indian Ocean > North Atlantic Ocean. Moreover, MARs increase in proportion to the concentrations of MeHg in regional seawater and zooplankton, linking MeHg accumulation in BFT to MeHg bioavailability at the base of each subbasin's food web. Observed global patterns correspond to levels of Hg in each ocean subbasin; the Mediterranean, North Pacific, and Indian Oceans are subject to geogenic enrichment and anthropogenic contamination, while the North Atlantic Ocean is less so. MAR in BFT as a global pollution index reflects natural and human sources and global thermohaline circulation. ? 2021 National Academy of Sciences. All rights reserved.
Subjects
Bioavailability
Bluefin tuna
Mercury accumulation rate
Mercury bioaccumulation
Ocean pollution
mercury
sea water
methylmercury derivative
Article
Atlantic Ocean
bioaccumulation
bioavailability
bluefin tuna
concentration (parameter)
controlled study
environmental enrichment
food web
Indian Ocean
Mediterranean Sea
nonhuman
Pacific Ocean
sea pollution
thermohaline circulation
tuna
water contamination
zooplankton
adverse event
animal
female
food chain
male
metabolism
pollution
sea
water pollutant
Animals
Biological Availability
Environmental Pollution
Female
Food Chain
Male
Mercury
Methylmercury Compounds
Oceans and Seas
Seawater
Tuna
Water Pollutants, Chemical
Type
journal article