Trophic transfer of methylmercury and brominated flame retardants in adjacent riparian and aquatic food webs: 13C indicates biotransport of contaminants through food webs

Xiaodan Wu; Laiguo Chen; Xiaoyun Li; Xingpei Cao; Xiaobo Zheng; Ronghua Li; Jia'en Zhang; Xiaojun Luo; Bixian Mai

doi:10.1016/j.envpol.2022.119433

Trophic transfer of methylmercury and brominated flame retardants in adjacent riparian and aquatic food webs: ¹³C indicates biotransport of contaminants through food webs

Environ Pollut. 2022 Aug 1:306:119433. doi: 10.1016/j.envpol.2022.119433. Epub 2022 May 9.

Authors

Xiaodan Wu¹, Laiguo Chen², Xiaoyun Li¹, Xingpei Cao³, Xiaobo Zheng⁴, Ronghua Li¹, Jia'en Zhang¹, Xiaojun Luo⁵, Bixian Mai⁵

Affiliations

¹ Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China.
² Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, MEE, Guangzhou, 510655, PR China.
³ State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of the Chinese Academy of Sciences, Beijing, 100049, China.
⁴ Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China. Electronic address: zhengxiaobo@scau.edu.cn.
⁵ State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China.

PMID: 35550129
DOI: 10.1016/j.envpol.2022.119433

Abstract

Biomagnification of persistent toxic substances (PTSs) in food chains is of environmental concern, but studies on biotransport of PTSs across aquatic and riparian food chains are still incomplete. In this study, biomagnification of several PTSs including methylmercury (MeHg), polybrominated diphenyl ethers (PBDEs), and 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE) was investigated in adjacent aquatic and riparian food webs. Concentrations of MeHg and PBDEs ranged from 2.37 to 353 ng/g dry weight (dw) and not detected (Nd) to 65.1 ng/g lipid weight (lw) in riparian samples, respectively, and ranged from Nd to 705 ng/g dw and Nd to 187 ng/g lw in aquatic samples, respectively. Concentrations of MeHg were significantly correlated with δ¹³C (p < 0.01) rather than δ¹⁵N (p > 0.05) values in riparian organisms, while a significant correlation was observed between concentrations of MeHg and δ¹⁵N (p < 0.01) in aquatic organisms. Biomagnification factors (BMFs) and trophic magnification factors (TMFs) of PBDE congeners were similar in riparian and aquatic food webs, while BMFs and TMFs of MeHg were much higher in aquatic food web than those in riparian food web. The results indicate the biotransport of MeHg from aquatic insects to terrestrial birds, and δ¹³C can be a promising ecological indicator for biotransport of pollutants across ecosystems.

Keywords: Biomagnification; Isotope; Methylmercury; Persistent organic pollutants; Trophic magnification factors.

MeSH terms

Animals
Ecosystem
Environmental Monitoring
Fishes
Flame Retardants* / analysis
Food Chain
Halogenated Diphenyl Ethers / analysis
Methylmercury Compounds*
Water Pollutants, Chemical* / analysis

Substances

Flame Retardants
Halogenated Diphenyl Ethers
Methylmercury Compounds
Water Pollutants, Chemical