上海大气微细颗粒物典型样本遗传毒性的季节变化研究

Studies of seasonal variation on genetic toxicity of typical fine particulate matter samples in Shanghai

为探究上海市冬、夏两季惠南和浦东2个位点PM_(2.5)不同组分的遗传毒性,利用SOS显色反应分别测试了PM_(2.5)在相同颗粒物浓度下的总颗粒物、有机提取组分和水溶性组分的遗传毒性.试验结果显示,冬、夏两季惠南总颗粒物诱发遗传毒性效应的最低浓度均为2mg·mL^(-1),浦东总颗粒物诱发遗传毒性效应的最低浓度分别为1 mg·mL^(-1)和2 mg·mL^(-1);惠南及浦东2个位点冬、夏两季的水溶性组分均在最高浓度2 mg·mL^(-1)下呈遗传毒性阳性;2个位点冬、夏两季的有机提取组分在0.000 2 mg·mL^(-1)至2 mg·mL^(-1)浓度范围内均未表现出遗传毒性效应.为进一步比较暴露于等体积的空气时,冬、夏两季惠南及浦东大气颗粒物的不同组分遗传毒性的相对强弱,比较了每立方米空气中以4-硝基喹啉氧化物(4-NQO)质量表示的不同组分的遗传毒性.结果表明,上海浦东点与惠南点的大气微细颗粒物的遗传毒性呈现季节性规律,冬季颗粒物的遗传毒性显著高于夏季,而且冬、夏两季总颗粒物及水溶性组分中具有遗传毒性的化学成分及其浓度可能存在一定的差异,结合现有研究中上海地区多个位点微细颗粒物中污染物浓度或含量冬季普遍高于夏季的研究结果,推测上海各地区的大气颗粒物遗传毒性均具有类似的季节性变化规律.有机提取组分的遗传毒性效应不明显,大气微细颗粒物的遗传毒性可能主要来自于水溶性组分.上海的郊区大气污染日益严重,相同季节浦东市区与惠南郊区的污染水平相当,遗传毒性也处于相近水平,推测相同季节上海浦东市区与惠南郊区大气颗粒物中的致遗传毒性成分具有一定的相似性.

To explore the genetic toxicity on different components of PM_(2.5) in Huinan and Pudong during winter and summer, the SOS chromotest is used to detect the genetic toxicity of the total particulate, the organic extract and the water-soluble component.Results shows that tests of the genetic toxicity on the total particulate in Huinan are positive at the highest concentration of 2 mg·mL^(-1) both in winter and summer, also are positive in Pudong respectively at the concentration of 1 mg-mL-1 in winter and at the highest concentration of 2 mg·mL^(-1) in summer. Tests of the genetic toxicity at two stations both in winter and summer on the water-soluble component are positive at the highest concentration of 2 mg·mL^(-1) and negative on the the organic extract in the range of 0.000 2 mg·mL^(-1) and 2 mg·mL^(-1). To further compare the genetic toxicity of the PM_(2.5) in Huinan and Pudong during winter and summer when exposed to the same volume air, the genetic toxicity of the different components are expressed as the content of the 4-nitroquinoline oxide(4-NQO) per cubic meter of air. Results indicat that the genetic toxicity of the fine particulate matter in Shanghai Puding and Huinan is seasonal and higher in summer than in winter. Furthermore the genotoxic component and the concentration of the total particulate and the water-soluble during winter and summer may be different. It, combined with the result of existing studies that pollutants concentration or components of fine particulate matter were generally higher in winter than in summer at multiple sites in Shanghai, is speculated that the genetic toxicity of atmospheric particulates in every part of Shanghai has similar seasonal change rule. The genotoxic effect of the organic extract is not significant. The main source of the genetic toxicity in the fine particulate matter may be the water-soluble component. The atmospheric pollution at Pudong stationwas continuously serious and equivalent to Huinan stationon the pollution level and the genetic toxicity in same seasons. It is speculated that the genotoxic chemical compositions of atmospheric particulate matter at Pudong station and Huinan station are similar.