兰州市某工业区大气PM_(2.5)中多环芳烃污染特征及健康风险评估

Pollution characterization and health risk assessment of polycyclic aromatic hydrocarbons in PM_(2.5) in an industrial area of Lanzhou

[背景]多环芳烃(PAHs)是重要的环境污染物,部分还具有致癌性,生活在工业区的居民可能承受着比其他地区更高的致癌健康风险。[目的]分析兰州市某工业区大气细颗粒物(PM_(2.5))中PAHs污染特征及健康风险。[方法]于2017年采集某工业区大气PM_(2.5)样品84份,其中采暖季35份,非采暖季49份。检测样品中16种优先控制PAHs单体水平,包括萘、苊、苊烯、芴、蒽、菲、苯并[a]蒽、屈、荧蒽、芘、苯并[a]芘、苯并[b]荧蒽、苯并[k]荧蒽、二苯并[a,h]蒽、苯并[g,h,i]苝、茚并[1,2,3-cd]芘。采用美国环保署推荐的当量法评估大气PM_(2.5)中PAHs对人群的健康风险和预期寿命损失,可接受的终身致癌风险水平在1×10^(-6)~1×10^(-4)范围。[结果]该工业区大气PM_(2.5)中PAHs全年总质量浓度(简称浓度)为(43.51±26.09)ng·m^(-3),采暖季总浓度[(60.64±30.88)ng·m^(-3)]高于非采暖季[(31.27±11.59)ng·m^(-3)](Z=-7.252,P<0.001)。全年、非采暖季PAHs均以2~3环为主,分别占47.96%、65.08%;采暖季PAHs以4环为主,占38.41%。PAHs总终身致癌风险值(VILCR)为1.24×10^(-5),其中采暖季(2.06×10^(-5))高于非采暖季(6.50×10^(-6)),成人(1.46×10^(-5))高于儿童(1.02×10^(-5))(分别Z=-7.223、-2.573,均P<0.05)。PAHs的居民预期寿命损失为90.59 min。[结论]兰州市某工业区采暖季大气PAHs终身致癌风险高于非采暖季,成人高于儿童,但都处于可接受水平。

[Background] Polycyclic aromatic hydrocarbons(PAHs) are important environmental pollutants,some of which are carcinogenic and could increase the carcinogenic health risks among residents living in relevant industrial areas than in other areas.[Objective] The purpose of this study is to analyze the pollution characteristics and potential health risks of PAHs in atmospheric fine particulate matters(PM_(2.5)) of an industrial area in Lanzhou City.[Methods] Eighty-fo ur atmospheric PM_(2.5) samples were collected from an industrial area in 2017,including 35 samples in heating season and 49 samples in non-heating season.Sixteen PAHs listed as priority pollutants were detected,including naphthalene,acenaphthene,acenaphthylene,fluorene,anthracene,phenanthrene,benzo [a]anthracene,chrysene,fluoranthene,pyrene,benzo[a] pyrene,benzo[b]fluoranthene,benzo[k] fluoranthene,dibenzo [a,h]anthracene,benzo[g,h,i] perylene,and indene[1,2,3-cd] pyrene.The equivalent method recommended by US Environmental Protection Agency was used to evaluate the health risk and life expectancy loss from PAHs in atmospheric PM_(2.5).The acceptable lifetime carcinogenic risk level was in the range of 1×10^(-6)-1×10^(-4).[Results] The annual total concentration of PAHs in atmospheric PM_(2.5) in the selected industrial area was(43.51±26.09) ng·m^(-3).The total concentration in heating season [(60.64±30.88) ng·m^(-3)] was significantly higher than that in non-heating season [(31.27±11.59) ng·m^(-3)](Z=-7.252,P<0.001).In the whole year and the non-heating season,the PAHs were dominated by 2-ring and 3-ring components,accounting for 47.96% and 65.08%,respectively,while in the heating season,the PAHs were dominated by 4-ring components,accounting for 38.41%.The incremental lifetime carcinogenic risk value (VILCR) from PAHs in the whole year was 1.24×10^(-5).The VILCR in the heating season(2.06×10^(-5)) was higher than that in the non-heating season(6.50×10^(-6)),and that in adults(1.46×10^(-5)) was higher than that in children(1.02×10^(-5))(Z=-7.223,-2.573,P<0.05).The life expectancy loss of PAHs was 90.59 min.[Conclusion] The lifetime carcinogenic risk of atmospheric PAHs in Lanzhou industrial zone in the heating season is higher than that in the non-heating season,and that in adults is higher than that in children,but they are within the preset acceptable range.