HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

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 concentrations in regions where oxygen depletion is shallow. Despite this natural biogeochemical control, the mercury hotspot in tuna caught near Asia is explained by elevated atmospheric mercury concentrations and/or mercury river inputs to the coastal shelf. While we cannot ignore the legacy mercury contribution from other regions to the Pacific Ocean (e.g., North America and Europe), our results suggest that recent anthropogenic mercury release, which is currently largest in Asia, contributes directly to present-day human mercury exposure.
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-03535193
Contributor : Lars-Eric Heimbürger-Boavida Connect in order to contact the contributor
Submitted on : Thursday, January 20, 2022 - 7:56:58 AM
Last modification on : Tuesday, May 10, 2022 - 3:25:44 PM
Long-term archiving on: : Thursday, April 21, 2022 - 6:19:02 PM

File

e2113032119.full.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives 4.0 International License

Identifiers

Citation

Anaïs Médieu, David Point, Takaaki Itai, Hélène Angot, Pearse Buchanan, et al.. Evidence that Pacific tuna mercury levels are driven by marine methylmercury production and anthropogenic inputs. Proceedings of the National Academy of Sciences of the United States of America , National Academy of Sciences, 2022, 119 (2), pp.e2113032119. ⟨10.1073/pnas.2113032119⟩. ⟨hal-03535193⟩

Share

Metrics

Record views

58

Files downloads

27