Human exposure to methylmercury through rice intake in mercury mining areas, Guizhou province, China

Environ Sci Technol. 2008 Jan 1;42(1):326-32. doi: 10.1021/es071948x.


The toxicity of methylmercury (Me-Hg) has caused widespread public human concern as a result of several widely publicized disasters. Me-Hg is highly toxic, and the nervous system is its principal target tissue for humans. Although the general population is primarily exposed to Me-Hg through contaminated fish and marine mammals, in Hg mining areas a long history of mining activities can produce serious Hg pollution to the local environment In a study of 98 persons from the Wanshan Hg mining area, hair Me-Hg levels indicated Me-Hg exposure. Rice, the staple food of the local inhabitants also showed high total Hg (T-Hg) and Me-Hg levels. The geometric mean concentration of T-Hg and mean concentration of Me-Hg in rice samples collected from 3 villages in Wanshan Hg mining area were 36.2 (ranging from 4.9 to 214.7), and 8.5 (ranging from 1.9 to 27.6) microg/kg, respectively, which were significantly elevated compared to the rice samples collected from a reference area, where the mean T-Hg and Me-Hg concentrations were 7.0 (3.2-15.1) and 2.5 (0.8-4.3) microg/kg, respectively. Pork meat, vegetable, and drinking water samples collected in Wanshan Hg mining area contained highly elevated T-Hg, but very low levels of Me-Hg. The relationships between the estimated rice Me-Hg intake and hair Me-Hg levels (r = 0.65, p < 0.001) confirmed rice with high Me-Hg levels indeed was the main route of Me-Hg exposure for the local residents in the Wanshan Hg mining area. From our study, we can conclude that the main human exposure to Me-Hg via food consumption is not restricted to fish, but in some cases in mining areas of China to frequent rice meals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brassica / metabolism
  • China
  • Daucus carota / metabolism
  • Environmental Monitoring
  • Environmental Pollutants / analysis*
  • Environmental Pollutants / metabolism*
  • Female
  • Food Contamination / analysis*
  • Hair / chemistry
  • Humans
  • Male
  • Meat / analysis
  • Mercury / analysis
  • Mercury / metabolism
  • Methylmercury Compounds / analysis*
  • Methylmercury Compounds / metabolism*
  • Middle Aged
  • Mining
  • Oryza / metabolism*
  • Water Supply / analysis


  • Environmental Pollutants
  • Methylmercury Compounds
  • Mercury