Abstract：
Methylmercury (MeHg) exposure via rice consumption poses health risk to residents in mercury contaminated areas, such as the Wanshan Hg mining area (WSMA) in southwest China. Making use of the published data for WSMA, this study developed a database of rice MeHg concentrations for different villages in this region for the years of 2007, 2012, 2017, and 2019. The temporal changes of human MeHg exposure, health effects, and economic benefits under different ecological remediation measures were then assessed. Results from this study revealed a decrease of 3.88 μg/kg in rice MeHg concentration and a corresponding reduction of 0.039 μg/kg/d in probable daily intake of MeHg in 2019 compared to 2007 on regional average in the WSMA. Ecological remediation measures in this region resulted in the accumulated economic benefits of $38.7 million during 2007-2022, of which 84 % was from pollution source treatment and 16 % from planting structure adjustment. However, a flooding event in 2016 led to an economic loss of $2.43 million (0.38 % of regional total Gross Domestic Product). Planting structure adjustment generates the greatest economic benefits in the short term, whereas pollution source treatment maximizes economic benefits in the long term and prevents the perturbations from flooding event. These findings demonstrate the importance of ecological remediation measures in Hg polluted areas and provide the foundation for risk assessment of human MeHg exposure via rice consumption.
摘要：
通过大米消费接触甲基汞对汞污染地区的居民构成健康风险。例如中国西南部的万山汞矿区（WSMA）。利用WSMA公布的数据，这项研究建立了该地区2007年、2012年、2017年和2019年不同村庄的水稻甲基汞浓度数据库。人类甲基汞暴露的时间变化，对健康的影响,然后评估了不同生态修复措施下的经济效益。这项研究的结果表明，与WSMA的区域平均水平相比，2019年的大米甲基汞浓度降低了3.88μg/kg，可能的每日甲基汞摄入量相应降低了0.039μg/kg/d。该地区的生态修复措施在2007-2022年期间累计产生了3870万美元的经济效益，其中84％来自污染源处理，16％来自种植结构调整。然而,2016年的洪水事件造成了243万美元的经济损失（占地区国内生产总值的0.38％）。种植结构调整在短期内产生最大的经济效益,而污染源处理在长期内最大限度地提高了经济效益，并防止了洪水事件的扰动。这些发现证明了生态修复措施在汞污染地区的重要性，并为人类通过大米消费暴露汞的风险评估奠定了基础。
