Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs.

ABSTRACT: Pacific Ocean tuna is among the most-consumed seafood products but contains relatively high levels of the neurotoxin methylmercury. Limited observations suggest tuna mercury levels vary in space and time, yet the drivers are not well understood. Here, we map mercury concentrations in skipjack tuna across the Pacific Ocean and build generalized additive models to quantify the anthropogenic, ecological, and biogeochemical drivers. Skipjack mercury levels display a fivefold spatial gradient, with maximum concentrations in the northwest near Asia, intermediate values in the east, and the lowest levels in the west, southwest, and central Pacific. Large spatial differences can be explained by the depth of the seawater methylmercury peak near low-oxygen zones, leading to enhanced tuna mercury con

SUBMITTER: Medieu A 

PROVIDER: S-EPMC8764691 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature