河北农居环境颗粒态汞污染特征及健康评估研究

近年来,我国农村环境问题日渐加重,大气颗粒态汞对人体健康的危害逐渐凸现出来,而已有研究对我国农居环境中的汞污染状况关注较少. 以颗粒态汞为研究对象,于2009年7、8月及2010年10~12月,对河北省6个村庄中的34个典型农居环境进行PM₁₀和PM_2.5膜采样,采用冷原子荧光法测定颗粒态汞质量浓度. 结果表明,同一季节时,厨房PM₁₀中汞质量浓度约是庭院PM₁₀中汞质量浓度的2倍; 在同一空间内,PM₁₀中汞质量浓度大小依次是冬季(3.004 ng·m^-3)>秋季(1.550 ng·m^-3)>夏季(1.127 ng·m^-3); 同一季节时,PM_2.5中汞质量浓度大小依次是厨房(0.795 ng·m^-3±0.337 ng·m^-3)>客厅(0.398 ng·m^-3±0.159 ng·m^-3)>庭院(0.321 ng·m^-3±0.143 ng·m^-3); PM_2.5中的汞质量浓度占PM₁₀中汞质量浓度的百分比为(52.4±13.5)%. 对农居环境PM_2.5中汞的健康风险度水平进行评价,不同人群中儿童的暴露水平最高,其年均超额危险度<10^-8. 可知农居环境PM_2.5中汞对农户的健康风险在可以忽略的水平.

Pollution Characteristics and Health Assessment of Particulate Mercury in Hebei Rural Households

Environment problems in rural areas have been increasing dramatically in recent years. Atmospheric particulate mercury has posed increasingly obvious threats to human health. However, there were few studies attaching importance on mercury pollution in rural residential environment. Taking particulate mercury as research objects, the studies in six villages of Hebei Province were carried out in July/August 2009 and October/September 2010.A number of PM₁₀ and PM_2.5 samples were taken in 34 typical households, using cold vapor atomic fluorescence to determine the content of particulate mercury. The results showed that the mercury concentration in PM₁₀ in kitchen was about twice that in the courtyard. In the same space, the mercury contents in PM₁₀ in a descending order were as follows: winter (3.004 ng·m^-3), autumn (1.550 ng·m^-3), summer (1.127 ng·m^-3); in the same season, the mercury levels in PM_2.5 in a descending order were as follows: kitchen (0.795 ng·m^-3±0.337 ng·m^-3),living room (0.398 ng·m^-3±0.159 ng·m^-3), yard (0.321 ng·m^-3±0.143 ng·m^-3); the Mercury content in PM_2.5 accounted for (52.4±13.5)% of that in PM₁₀. Evaluation of the health risks of mercury in PM_2.5 revealed that children were exposed to the highest level, whose average annual excess risk was below 10^-8. Therefore, the health risk of peasants living in rural residential environment was at a negligible level.