Methylmercury biomagnification in aquatic food webs of Poyang Lake, China : Insights from amino acid signatures

Copyright © 2020. Published by Elsevier B.V..

As the dominant mercury species in fish, methylmercury (MeHg) biomagnifies during its trophic transfer through aquatic food webs. MeHg is known to bind to cysteine, forming the complex of MeHg-cysteine. However, relationship between MeHg and cysteine in large-scale food webs has not been explored and contrasted with MeHg biomagnification models. Here, we quantified the compound-specific nitrogen isotopic analysis of amino acids (CSIA-AA), MeHg, and amino acid composition in aquatic organisms of Poyang Lake, the largest freshwater lake in China. The trophic positions (TPAA) of organisms ranged from 1.0 ± 0.1-3.7 ± 0.2 based on CSIA-AA approach. The trophic magnification factor (TMF) of MeHg, derived from the regression slope of Log-transformed MeHg in organisms upon their TPAA for the entire food web was 9.5 ± 0.5. Significantly positive regression between MeHg and cysteine (R2 = 0.64, p < 0.01) was documented, suggesting MeHg-cysteine complex may potentially play a critical role in the bioaccumulation of MeHg. Furthermore, TMFs of MeHg calculated with and without cysteine normalization compared well (7.7-8.7) when excluding primary producers. Our results implied that MeHg may biomagnify as the complex of MeHg-cysteine and contribute to our understanding of MeHg trophic transfer at the molecular level.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:404

Enthalten in:

Journal of hazardous materials - 404(2021), Pt A vom: 15. Feb., Seite 123700

Sprache:

Englisch

Beteiligte Personen:

Zhang, Zhongyi [VerfasserIn]
Wang, Wen-Xiong [VerfasserIn]
Zheng, Nengjian [VerfasserIn]
Cao, Yansheng [VerfasserIn]
Xiao, Hongwei [VerfasserIn]
Zhu, Renguo [VerfasserIn]
Guan, Hui [VerfasserIn]
Xiao, Huayun [VerfasserIn]

Links:

Volltext

Themen:

Biomagnification
Compound-specific nitrogen isotope of amino acid
Cysteine
FXS1BY2PGL
Journal Article
MeHg
Mercury
Methylmercury Compounds
Poyang Lake
Research Support, Non-U.S. Gov't
Water Pollutants, Chemical

Anmerkungen:

Date Completed 14.05.2021

Date Revised 14.05.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jhazmat.2020.123700

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM316152374