KEYNOTE An overview of mercury pollution in China

China is the largest mercury producing, consumption and emission country over the global due to rapid economy development during the last decades. We have conducted intensive monitoring of mercury distribution and deposition... [ view full abstract ]

China is the largest mercury producing, consumption and emission country over the global due to rapid economy development during the last decades. We have conducted intensive monitoring of mercury distribution and deposition in ambient air in remote areas cross mainland China since 2007. Our data showed that total gaseous mercury concentrations in ambient air in China are generally elevated compared to the global background values measured at remote sites in Europe and North America as a result of large manmade Hg emissions. However, our studies showed that fish in China generally contained low levels of mercury. Because almost all fish in Chinese market are aquaculture production and these fish are growing very fast, the effect of bioaccumulation and biomagnification of methylmercury in fish body will not be significant so that mercury concentrations in fish are very low. As a result, mercury exposure levels to Chinese people from fish eating are very low. Our studies showed that at mercury contaminated sites such as mercury mining areas, the surface environment compartments are seriously contaminated with mercury. We found that rice has a strong ability to accumulate MeHg and rice consumption constitutes health risk of MeHg exposure to local inhabitants in mercury mining areas. Therefore, the increasing Hg deposition from air in mainland China may increase MeHg concentrations in rice, which may pose potential health risk for general population in China as rice is the staple food for a large population in China.