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Human Methylmercury Exposure and Potential Impacts in Central Tibet: Food and Traditional Tibetan Medicine

Abstract

Methylmercury presents potent neurotoxicity to humans. Fish consumption is the leading source of human exposure to methylmercury worldwide. However, the exposure source in Tibet remains poorly understood because of the scarcity of observational data on most Tibetan foods, although high mercury levels were recently detected in some traditional Tibetan medicines. Here, the results of field investigations show that the joint consumption of traditional Tibetan medicines (TTMs), fish, and rice constitutes a primary exposure pathway to methylmercury in Tibetans and that the probable daily intake of methylmercury is close to that for many coastal regions. People who are young and high-income may have higher methylmercury exposure levels mainly because of economic development and cultural exchanges among regions. Our analysis indicates that a large proportion of the Tibetan population are likely to face a high methylmercury exposure risk and that mercury-susceptible populations in Tibet should be attentive to consuming TTMs with fish.

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Acknowledgements

The authors thank Junming Guo at the Cold and Arid Regions Environmental and Engineering Research Institute and Qianggong Zhang at the Institute of Tibetan Plateau Research for their help with the measurements. This work was funded by the National Natural Science Foundation of China (41630748, 41977311 and 41821005). The involvement of Deji was supported by the key R&D and transformation plan of the Science and Technology Department of Tibet (XZ-201801-GB-05).

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Correspondence to Maodian Liu or Xuejun Wang.

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Cheng, M., Liu, M., Li, D. et al. Human Methylmercury Exposure and Potential Impacts in Central Tibet: Food and Traditional Tibetan Medicine. Bull Environ Contam Toxicol 107, 449–458 (2021). https://doi.org/10.1007/s00128-021-03216-5

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Keywords

  • Methylmercury
  • Dietary exposure
  • Economic development
  • Cultural exchanges
  • Traditional Tibetan medicine
  • Joint ingestion