【作者】 徐春雨；

【导师】 徐东群；

【作者基本信息】 中国疾病预防控制中心 ， 劳动卫生与环境卫生， 2008， 硕士

【摘要】 目的通过环境暴露监测和暴露生物标志物的监测,综合评价研究人群对苯、PM_2.5及其共存多环芳烃的暴露水平,并通过对早期遗传损伤效应指标和基因多态性的监测,探讨可用于空气污染遗传毒性监测的效应标志物以及可反映个体易感性的易感性标志物。方法1.选择燃煤污染相对较轻的夏季（2007年6月）进行调查,以62名北京市某城区交警和35名郊区某社区居民为研究对象,通过统一的问卷调查收集研究人群的姓名、年龄、饮酒、吸烟、职业史等一般信息;2.通过对代表性污染物苯、PM_2.5及其共存多环芳烃（PAHs）的连续两天的环境暴露监测,以及苯的代谢产物苯巯基尿酸（S-PMA）、芘的代谢产物1-羟基芘（1-OHP）的监测,综合评价研究人群的空气污染物暴露水平。环境空气中苯的浓度测定采用二次热解析-气相色谱法,PM_2.5质量浓度测定采用重量法,PM_2.5共存PAHs测定采用超声萃取-高效液相色谱法,尿中1-OHP测定采用酶水解-高效液相色谱法,尿中S-PMA测定采用ELISA试剂盒法;3.通过监测尿中8-羟基脱氧鸟苷（8-OHdG）和外周血淋巴细胞DNA链断裂水平,探讨反映空气污染早期遗传损伤的效应标志物。调查对象尿中8-OHdG浓度测定采用ELISA试剂盒法,外周血淋巴细胞DNA链断裂水平测定采用单细胞凝胶电泳法（SCGE）;4.通过监测谷胱甘肽硫转移酶M1（GSTM1）和T1（GSTT1）基因多态性,探讨反映个体易感性的易感性标志物。GSTM1和GSTT1基因型的测定采用多重PCR法;5.采用分层分析和多元回归模型进行混杂因素的控制,综合分析空气污染物暴露水平及基因多态性与遗传损伤效应指标间的相关关系。结果1.交警组的苯、PM_2.5、苯并[a]芘的环境暴露浓度分别为:56±36μg/m³、96±38μg/m³、3.20±1.89ng/m³,均高于郊区居民组:24±17μg/m³、45±22μg/m³、1.54±0.76 ng/m³;交警组的暴露生物标志物S-PMA、1-OHP浓度分别为:3.83±3.39μmol/mol肌酐和0.56±0.48μmol/mol肌酐,显著高于郊区居民组:2.42±2.63μmol/mol肌酐和0.33±0.28μmol/mol肌酐（P＜0.05）;2.调查对象尿中1-OHP、S-PMA浓度与8-OHdG水平显著正相关（P＜0.05）,在校正了吸烟、饮酒、年龄等因素影响后,S-PMA与8-OHdG相关关系仍具有统计学意义（P＜0.01）;3.单因素分析和多元回归分析没有发现空气污染物暴露水平对外周血淋巴细胞DNA链断裂水平的影响;4.没有发现GSTM1和GSTT1基因多态对调查对象尿中8-OHdG和外周血淋巴细胞DNA链断裂水平的影响。结论环境暴露和暴露标志物监测结果均表明,本次研究中的交警组人群苯、PM_2.5及其共存PAHs的暴露水平显著高于郊区居民组,与其它研究报道中的暴露监测结果比较表明,本次研究的调查对象处于较高的空气污染物暴露水平;调查对象尿中8-OHdG与空气污染物暴露水平显著相关,提示其可以作为反映空气污染早期遗传损伤的效应标志物;外周血淋巴细胞DNA断裂尚不能满足对空气污染早期遗损伤监测的要求;没有发现GSTM1、GSTT1基因多态对空气污染物遗传损伤效应的影响。更多还原

【Abstract】 The aim of this study was to assess the exposure to benzene,PM_2.5 and polycyclic aromatic hydrocarbons（PAH_S） associated with PM_2.5,and to explore the biomarkers of effect and susceptibility that could be used in monitoring the genotoxic effect of ambient air pollution.Methods1.In June 2007,Sixty-two traffic policemen and thirty-five male suburban inhabitants were selected.The information on smoking,drinking alcohol, exercising habit and so on was investigated by questionnaire.2.The exposure levels of benzene,PM_2.5 and PAHs associated with PM_2.5 were assessed by both ambient air monitoring and exposure biomonitoring.The atmospheric air samples were collected within two consecutive days in the work place of traffic policeman and in the residential area of suburban inhabitants respectively.The benzene concentrations were determined by thermal desorption-gas chromatography,while the PAHs concentrations were determined by high performance liquid chromatography（HPLC）.As internal dose,the 1-hydroxylpyrene（1-OHP） of pyrene metabolite and S-phenylmercapturic acid （S-PMA） of benzene metabolite were determined by HPLC and ELISA kit respectively.3.As the candidates of genotoxic effect biomarkers,the 8-hydroxydeoxyguanosine （8-OHdG） in the urinary and DNA strand breaks（SB） of peripheral blood lymphocytes were determined by ELISA kit and single cell gel electrophoresis assay（SCGE） respectively.4.As the candidates of susceptibility biomarkers for air pollution,the genetic polymorphisms of glutathione S-transferase M1（GSTM1） and glutathione S-transferase T1（GSTT1） were identified using multiplex polymerase chain reaction（PCR）.5.Multiple regression analyses were performed to control the confounding factors and investigate the effect of air pollution and genetic polymorphisms on DNA damage.Results1.The average levels of benzene,PM_2.5 and benzo（a）pyrene（BaP） in the traffic policeman group were 56±36μg/m³、96±38μg/m³、3.20±1.89ng/m³ respectively, while the corresponding values in the suburban inhabitant group were 24±17μg/m³、45±22μg/m³、1.54±0.76 ng/m³ respectively.The concentrations of urinary 1-OHP and S-PMA in traffic policeman group were 3.83±3.39μmol/mol creatinine and 0.56±0.48μmol/mol creatinine respectively,which were significant higher than the corresponding values in the suburban inhabitant group: 2.42±2.63μmol/mol creatinine and 0.33±0.28μmol/mol creatinine（P＜0.05）.2.The concentrations of urinary 1-OHP and S-PMA were both significantly positive correlated with the urinary 8-OHdG.After adjusting for confound factors,the correlation between S-PMA and 8-OHdG was still significant（P＜0.01）.3.No influence of air pollution and other investigated factors on the levels of DNA strand breaks was found.4.No influence of GSTM1 and GSTT1 genotype on the levels of urinary 8-OHdG or DNA strand break was found.ConelusionBoth the environmental air pollutant monitoring and internal dose measurement indicated that traffic policemen exposed to higher level of air pollutants than the control group.The urinary 8-OHdG might be an early genotoxic effect biomarker of air pollution.The DNA strand breaks were not a sensitive genotoxic effect biomarker of air pollution.Whether genetic polymorphism of GSTM1 and GSTT1 could be used as biomarkers of susceptibility for ambient air pollutants exposure still needs further study.更多还原