Open AccessBluefin tuna reveal global patterns of mercury pollution and bioavailability in the world's oceans
Author(s) -
ChunMao Tseng,
Shin Jing Ang,
Yi Sheng Chen,
JenChieh Shiao,
Carl H. Lamborg,
Xiaoshuai He,
John R. Reinfelder
Publication year - 2021
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2111205118
Subject(s) - mercury (programming language) , bioaccumulation , environmental science , oceanography , methylmercury , thermohaline circulation , mediterranean sea , food web , seawater , pollution , tuna , zooplankton , environmental chemistry , mediterranean climate , fishery , trophic level , ecology , biology , chemistry , geology , computer science , programming language , fish <actinopterygii>
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.