College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China.
Sci Rep. 2017 May 9;7:46545. doi: 10.1038/srep46545.
Mercury contamination in food can pose serious health risks to consumers and coal-fired power plants have been identified as the major source of mercury emissions. To assess the current state of mercury pollution in food crops grown near coal-fired power plants, we measured the total mercury concentration in vegetables and grain crops collected from farms located near two coal-fired power plants. We found that 79% of vegetable samples and 67% of grain samples exceeded the PTWI's food safety standards. The mercury concentrations of soil samples were negatively correlated with distances from the studied coal-fired power plants, and the mercury contents in lettuce, amaranth, water spinach, cowpea and rice samples were correlated with the mercury contents in soil samples, respectively. Also, the mercury concentrations in vegetable leaves were much higher than those in roots and the mercury content of vegetable leaves decreased significantly after water rinses. Our calculation suggests that probable weekly intake of mercury for local residents, assuming all of their vegetables and grains are from their own farmland, may exceed the toxicologically tolerable values allowed, and therefore long-term consumptions of these contaminated vegetables and grains may pose serious health risks.
食物中的汞污染会对消费者的健康造成严重威胁，燃煤电厂已被确定为汞排放的主要来源。为了评估燃煤电厂附近种植的粮食作物中汞污染的现状，我们测量了从两个燃煤电厂附近的农场采集的蔬菜和粮食作物中的总汞浓度。我们发现，79%的蔬菜样本和 67%的粮食样本超过了暂定每周可耐受摄入量的食品安全标准。土壤样本中的汞浓度与距研究燃煤电厂的距离呈负相关，生菜、苋菜、空心菜、豇豆和水稻样本中的汞含量分别与土壤样本中的汞含量相关。此外，蔬菜叶片中的汞浓度远高于根部，且经水冲洗后，蔬菜叶片中的汞含量显著降低。我们的计算表明，假设当地居民食用的所有蔬菜和谷物都来自自家农田，他们每周摄入汞的量可能超过了毒理学可耐受值，因此长期食用这些受污染的蔬菜和谷物可能会对健康造成严重威胁。
