2015—2017年兰州大气PM2.5中10种元素的健康风险分析

Analysis on health risks of ten elements in ambient PM2.5 in Lanzhou during 2015-2017

目的了解2015-2017年兰州市大气PM2.5中元素对人群健康的影响。方法于2015-2017年每月10-16日在兰州市城关区、西固区进行大气PM2.5采样,共采集样品501份,分析PM2.5及其中Sb、Al、As、Cd、Cr、Ni、Pb、Hg、Mn和Se10种元素的污染特征,采用美国环境保护局健康风险评估模型对呼吸暴露的健康风险进行分析。结果2015-2017年城关区、西固区PM2.5的年均浓度分别为0.09、0.08、0.05 mg/m^3和0.08、0.08、0.05 mg/m^3,均超过《环境空气质量标准》(GB3095-2012)中二级标准限值。城关区、西固区大气PM2.5中10种元素浓度由高到低分别为Al>Pb>Mn>As>Ni>Cr>Cd>Sb>Se>Hg,Al>Pb>Mn>As>Ni>Cr>Sb>Se>Cd>Hg,两地区As和Cr的浓度均超过GB 3095-2012限值。10种元素对成年男女性及儿童的年均超额危险度在5.03×10^-12~2.97×10^-7之间,低于人群可接受的危险度水平(10-6),其中城关区10种元素的超额危险度由高到低依次为As>Cr>Cd>Ni>Al>Pb>Mn>Hg>Sb>Se,西固区依次为Cr>As>Cd>Ni>Al>Pb>Mn>Hg>Sb>Se,10种元素对成年男性的超额危险度高于成年女性和儿童。结论两个监测点大气中的Cr和As对人群健康的危险度相对较高,且应关注各元素对成年男性的健康影响。

Objective To explore the elements level in ambient PM2.5 in Lanzhou and its health effect during 2015-2017.Methods A total of 501 air samples were collected in Chengguan and Xigu districts,in Lanzhou in period from the 10th to 16th in each month during 2015-2017.The inhalation exposure and risk assessment of Sb,Al,As,Cd,Cr,Pb,Hg,Mn,Se and Ni in ambient PM2.5 were carried out by using USEPA Heath Risk Assessment Model.Results The annual average concentration of PM2.5 were 0.09,0.08,0.05 and 0.08,0.08,0.05 mg/m^3 in Chengguan and Xigu districts respectively,all of which exceeded the limits for grade two ruled by Ambient Air Quality Standards(GB 3095-2012).The concentrations of ten elements in PM2.5 ranked as Al>Pb>Mn>As>Ni>Cr>Cd>Sb>Se>Hg in Chengguan district,and Al>Pb>Mn>As>Ni>Cr>Sb>Se>Cd>Hg in Xigu district.The concentrations of Cr and As all exceeded the limits of GB 3095-2012.The annual excess risks of ten elements by respiratory pathway exposure were 5.03×10^-12-2.97×10^-7,lower than the acceptable risk level of population(10-6).The excess risk of ten elements ranked as As>Cr>Cd>Ni>Al>Pb>Mn>Hg>Sb>Se in Chengguan district,and Cr>As>Cd>Ni>Al>Pb>Mn>Hg>Sb>Se in Xigu district.The health impact induced by the ten elements for population ranked as adult males>adult females>children.Conclusion Cr and As in the air collected from two monitoring sites are more dangerous to human health,and the effect of elements on adult male health should be paid more attention to.