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

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

  • Zhongyi Zhang
  • Nengjian Zheng
  • Yansheng Cao
  • Hongwei Xiao
  • Renguo Zhu
  • Hui Guan
  • Huayun Xiao

Detail(s)

Original languageEnglish
Article number123700
Journal / PublicationJournal of Hazardous Materials
Volume404
Issue numberPart A
Online published18 Aug 2020
Publication statusPublished - 15 Feb 2021

Abstract

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.

Research Area(s)

  • Biomagnification, Compound-specific nitrogen isotope of amino acid, Cysteine, MeHg, Poyang Lake

Citation Format(s)

Methylmercury biomagnification in aquatic food webs of Poyang Lake, China : Insights from amino acid signatures. / Zhang, Zhongyi; Wang, Wen-Xiong; Zheng, Nengjian; Cao, Yansheng; Xiao, Hongwei; Zhu, Renguo; Guan, Hui; Xiao, Huayun.

In: Journal of Hazardous Materials, Vol. 404, No. Part A, 123700, 15.02.2021.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review