Loading [MathJax]/jax/output/HTML-CSS/fonts/TeX/fontdata.js
Preprints
https://doi.org/10.5194/egusphere-2025-312
https://doi.org/10.5194/egusphere-2025-312
30 Jan 2025
 | 30 Jan 2025
Status: this preprint is open for discussion and under review for Biogeosciences (BG).

Bioconcentration as a key driver of Hg bioaccumulation in high trophic level fish

David Amptmeijer and Johannes Bieser

Abstract. The ability of monomethylmercury (MMHg+) to bioaccumulate in seafood is of concern due to its neurotoxic properties. Understanding the bioaccumulation of MMHg+ is challenging because the MMHg+ content at higher trophic levels depends on both bioconcentration and biomagnification. Furthermore, Hg can occur in several chemical species, including Hg2+ and MMHg+, which both bioaccumulate. Although the dominant pathway for MMHg+ bioaccumulation into seafood is the bioconcentration of MMHg+ in primary producers and the subsequent biomagnification to higher trophic levels, other pathways can contribute to MMHg+ bioaccumulation. In this study, we quantify the importance of the bioaccumulation of Hg2+ and the bioconcentration of MMHg+ in higher trophic levels in the bioaccumulation of MMHg+ in high trophic level fish by running a fully coupled 1D water column Hg bioaccumulation model under 3 hydrodynamic regimes typical for the North and Baltic Seas. We find that Hg2+ bioaccumulation does not influence the bioaccumulation of MMHg+ but the bioconcentration of MMHg+ plays an important role. Although direct bioconcentration accounts for < 15 % of MMHg+ bioaccumulation in cod, the cumulative effect of bioconcentration on all trophic levels increases the MMHg+ content of cod by 28–48 %. We show that up to the highest trophic level modeled (TL = 3.7), the percentage of MMHg+ that originates from consumer bioconcentration increases with an average of 15 % per trophic level. These results demonstrate that bioconcentration in consumers is essential to accurately model the bioaccumulation of MMHg+ at higher trophic levels.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Share
Download
Short summary
The mercury (Hg) form of most concern is monomethylmercury (MMHg⁺) due to its neurotoxicity...
Share