重庆市大气细颗粒物中多环芳烃组分与男性精子DNA损伤的关联研究

Association between fine particulate matter bound polycyclic aromatic hydrocarbons and DNA damage of male sperm in Chongqing

目的探讨重庆市大气细颗粒物(PM2.5)中的多环芳烃(polycyclic aromatic hydrocarbons,PAHs)暴露对男性精子DNA的损害效应。方法研究对象来源于2013、2014年重庆市大学生男性生殖健康研究队列(male reproductive health in Chongqing college students,MARHCS),检测采样期间大气PM2.5中的低环PAHs(2~4环)和高环PAHs(5~6环)各组分的含量;采用单细胞凝胶电泳实验检测精子DNA损伤;采用混合效应模型探讨PAHs各组分的暴露程度与男性大学生精子DNA损伤水平之间的关联。结果2013年大气细颗粒物中的PAHs组分以低环PAHs为主,其中菲、芴、芘的占比最高,而2014年大气细颗粒物中则以高环PAHs为主,如茚并[1,2,3-cd]芘、苯并[g,h,i]苝、苯并[a]芘等。在2014年,男性大学生的精子DNA损伤指标如彗星尾长、尾矩和Olive尾矩较2013年明显增加(P<0.05)。混合效应模型结果显示:低环PAHs中的荧蒽、苊烯、芘和总低环PAHs与精子DNA损伤指标中的彗星尾长和尾矩呈负相关。高环PAHs中的苯并[k]荧蒽、苯并[b]荧蒽和二苯并[a,h]蒽与精子DNA损伤指标中的彗星尾长呈正相关[β(95%CI):108.987(43.754~203.820)、158.700(65.957~303.272)、185.708(67.350~387.775),校正P均<0.05];与彗星尾矩呈正相关[β(95%CI):449.204(260.066~737.695)、683.108(374.515~1192.387)、683.108(374.515~1192.387),校正P均<0.05]。结论重庆市大气细颗粒物中的高环PAHs组分暴露,可能导致精子DNA损伤效应增加。

Objective To investigate the association between exposure to polycyclic aromatic hydrocarbons(PAHs)in atmospheric fine particulate matter(PM2.5)and sperm DNA damage in Chongqing.Methods The subjects were sampled from our previously established cohort of the male reproductive health in Chongqing college students(MARHCS)study.The concentrations of PAHs(collected during the sampling periods)with low fused aromatic rings(2~4 rings)and with high fused aromatic rings(5~6 rings)in the air PM2.5 filter membranes were detected.Single cell gel electrophoresis(Comet assay)was used to evaluate DNA damage.Finally,the mixed-effects model was used to investigate the relationships between the exposure concentrations of PAHs components in PM2.5 and severity of sperm DNA damage.Results In 2013,the low molecular weight(LMW)PAHs accounted for a large proportion in atmospheric fine particles,mainly phenanthrene,fluorene and pyrene.While,the high molecular weight(HMW)PAHs dominated in 2014,such as indeno[1,2,3-cd]pyrene,benzo[g,h,i]perylene and benzo[a]pyrene.Sperm DNA damage indicators,such as tail length,tail moment and Olive tail moment were more common in the cohort in the year of 2014 than in 2013(all P<0.05).The results of the mixed model showed that the concentrations of fluoranthene,acenaphthene,pyrene and∑LMW PAHs were negatively correlated with tail length and tail moment.The concentrations of benzo[k]fluoranthene,benzo[b]fluoranthene and dibenz[a,h]anthracene were positively correlated with tail length[β(95%CI):108.987(43.754~203.820),158.700(65.957~303.272),185.708(67.350~387.775),respectively;all corrected P<0.05]and with tail moment[β(95%CI):449.204(260.066~737.695),683.108(374.515~1192.387),683.108(374.515~1192.387),respectively;all corrected P<0.05].Conclusion The exposure of HMW PAHs in Chongqing atmospheric fine particles may lead to the enhancement of sperm DNA damage.