State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
Center for Advances in Water and Air Quality, Lamar University, Beaumont, Texas 77710, USA.
Environ Sci Process Impacts. 2022 May 25;24(5):634-648. doi: 10.1039/d2em00039c.
Mercury (Hg) is a toxic metal released into the environment through human activities and natural processes. Human activities have profoundly increased the amount of Hg in the atmosphere and altered its global cycling since the Industrial Revolution. Gaseous elemental Hg is the predominant form of Hg in the atmosphere, which can undergo long-range transport and atmospheric deposition into the aquatic systems. Hg deposition elevates the methylmercury (MeHg) level in fish through bioaccumulation and biomagnification, which poses a serious human health risk. Acute poisoning of MeHg can result in Minamata disease, while low-level long-term exposure in pregnant women can reduce the intelligence quotient of infants. After five sessions of intergovernmental negotiation, the Minamata Convention on mercury entered into force in August 2017 to protect human health and the environment from Hg pollution. Currently China contributes the largest quantity of Hg production, consumption, and emission globally. However, the status of Hg pollution in the environment in China and its associated health risk remains relatively unknown, which hinders the development of implementation plans of the Minamata Convention. In this paper, we provide a comprehensive review on the atmospheric release of Hg, distribution of air Hg concentration, human exposure to MeHg and health impacts caused by Hg pollution in China. Ongoing improvement of air pollution control measures is expected to further decrease anthropogenic Hg emissions in China. Air Hg concentrations in China are higher than the background values in the Northern Hemisphere, with spatial distribution largely influenced by anthropogenic emissions. Long-term observations of GEM in China show a decline in recent years. The net Hg transport outflow from China in 2013 is estimated to be 511 t year, and ∼60% of such outflow is caused by natural surface Hg emissions. Hg concentrations in fish and rice in China are relatively low and therefore the associated risks of human Hg exposure are low. Future research needs and recommendations for the implementation of the Minamata Convention are also discussed in this paper.
汞（Hg）是一种通过人类活动和自然过程释放到环境中的有毒金属。自工业革命以来，人类活动极大地增加了大气中汞的含量，并改变了其全球循环。气态元素汞是大气中汞的主要形式，它可以通过长距离传输和大气沉积进入水系统。Hg 的沉积通过生物积累和生物放大作用提高了鱼类中的甲基汞（MeHg）水平，这对人类健康构成了严重威胁。急性 MeHg 中毒可导致水俣病，而孕妇的低水平长期暴露会降低婴儿的智商。经过五轮政府间谈判，《汞水俣公约》于 2017 年 8 月生效，以保护人类健康和环境免受 Hg 污染。目前，中国是全球生产、消费和排放 Hg 最多的国家。然而，中国环境中 Hg 污染的状况及其相关的健康风险仍然知之甚少，这阻碍了《水俣公约》实施计划的制定。本文全面综述了中国大气 Hg 的释放、空气 Hg 浓度分布、人类对 MeHg 的暴露以及 Hg 污染对健康的影响。正在进行的空气污染控制措施的改进有望进一步减少中国人为 Hg 排放。中国空气中的 Hg 浓度高于北半球的背景值，其空间分布在很大程度上受人为排放的影响。中国 GEM 的长期观测显示近年来呈下降趋势。2013 年，中国从大气中输出的净 Hg 通量估计为 511 t 年，其中约 60%的输出是由自然地表 Hg 排放引起的。中国鱼类和大米中的 Hg 浓度相对较低，因此人类 Hg 暴露的相关风险较低。本文还讨论了实施《水俣公约》的未来研究需求和建议。
