China's municipal wastewater policies enhanced seafood safety and offset health risks from atmospheric mercury emissions in the past four decades

Xingrui Cai; Mengqi Yang; Maodian Liu; Yuang Chen; Chenghao Yu; Haoran Zhang; Qianru Zhang; Shijun Ma; Xinyu Dou; Jing Meng; Xuejun Wang

doi:10.1038/s43016-024-01093-9

China's municipal wastewater policies enhanced seafood safety and offset health risks from atmospheric mercury emissions in the past four decades

Nat Food. 2025 Jan 2. doi: 10.1038/s43016-024-01093-9. Online ahead of print.

Authors

Xingrui Cai^{1

2}, Mengqi Yang³, Maodian Liu^{4

5}, Yuang Chen⁶, Chenghao Yu⁷, Haoran Zhang⁸, Qianru Zhang^{1

9}, Shijun Ma², Xinyu Dou^{10

11}, Jing Meng¹², Xuejun Wang¹³

Affiliations

¹ MOE Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, China.
² The Bartlett School of Sustainable Construction, University College London, London, UK.
³ School of Environment, Tsinghua University, Beijing, China.
⁴ MOE Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, China. maodian.liu@pku.edu.cn.
⁵ School of the Environment, Yale University, New Haven, CT, USA. maodian.liu@pku.edu.cn.
⁶ Institute for Data, Systems, and Society, Massachusetts Institute of Technology, Cambridge, MA, USA.
⁷ Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, China.
⁸ Centre for Environmental Policy, Imperial College London, London, UK.
⁹ Nicholas School of the Environment, Duke University, Durham, NC, USA.
¹⁰ Department of Earth System Science, Tsinghua University, Beijing, China.
¹¹ Department of Earth System Science, Stanford University, Stanford, USA.
¹² The Bartlett School of Sustainable Construction, University College London, London, UK. jing.j.meng@ucl.ac.uk.
¹³ MOE Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, China. xjwang@urban.pku.edu.cn.

PMID: 39748033
DOI: 10.1038/s43016-024-01093-9

Abstract

The neurotoxin methylmercury in seafood threatens food safety worldwide. China has implemented stringent wastewater policies, established numerous treatment facilities and enforced rigorous water quality standards to address pollution in its waterways. However, the impact of these policies on seafood safety and methylmercury exposure remains unknown. Here we developed a process-based model showing that, although mercury reductions from municipal wastewater policies accounted for only 9% of atmospheric mercury emissions during 1980-2022, these measures unexpectedly prevented ${102,000}_{- 6,600}^{+ 11,000}$ mercury-related deaths and counteracted nearly two thirds of potential deaths from those emissions. Furthermore, these policies ensured that $146_{- 9}^{+ 8}$ megatonnes of freshwater seafood met the World Health Organization and China's mercury-safety standards, preventing $US $ 498_{- 29}^{+ 32}$ billion in economic losses. Finally, we explore how China, as the primary global seafood producer and exporter, could develop municipal wastewater policies at the regional level to reduce aquatic pollutants and unlock the health benefits of seafood consumption.

Abstract

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