Research On The Exposure Of Beijing College Students To Organic Flame Retardants In Indoor Dust

The widespread and use and hazards to environment and human beings of brominated flame retardants(BFRs),especially polybrominated diphenyl ethers(PBDEs)have been drawing people's attention.In recent years.,due to the limitation of BFRs worldwide,organophosphate flame retardants(OPFRs)and alternative brominated flame retardants(Alt-BFRs)as replacement retardants,have also become environmentally ubiquitous.Many studies have reported that Indoor dust is generally the main source of human exposure to BFRs and OPFRs.Disparities in concentrations of BFRs and OPFRs between males and females were reported before,but the causes of this disparity is poorly understood.Furthermore,there are no related studies on how indoor dust works on this gender disparity.In this study,Minzu University of China,Beijing was taking as the research site,and human hairs,human urine and the corresponding indoor dusts were collected.11 PBDE congeners,7 Alt-BFRs and 9 kinds of OPFRs were analysed in those samples to find the parterns of BFRs and OPFRs.estimate exposure to BFRs and OPFRs in indoor dust for men and women and investigate the role indoor dust plays in BFRs and OPFRs concentration differences in samples from men and womenThe total PBDE concentrations were significantly(three times)higher(p=0.012)in hair from females than males(means 372 and 109 ng/g,respectively).The mean total PBDE concentrations in classroom and dormitory dust were 36100 and 2012 ng/g,respectively.The PBDE patterns were different in the male and female hair samples,as were the patterns in the classroom and dormitory dust.There are no reports concerning human exposure to BFRs via dust that was assessed considering studying and residential environments simultaneously.The differences between BFR exposure for males and females and the differences between BFR concentrations in hair samples from males and females were consistent for 71.4%of the compounds.However,using dormitory dust only in the calculations gave consistent differences for only 28.6%of the compounds,suggesting that the BFR concentration differences in hair were mainly caused by females spending much more time than males in classrooms.The tri-o-cresylphosphate(TOCP),tri-p-cresylphosphate(TPCP).and tris(2-chloroisopropyl)phosphate(TCIPP)concentrations were significantly higher(p=0.049.0.023,and 0.027,respectively)in urine from the female students than in urine from the male students.Similar differences were found between males and females in terms of OPFR exposure and OPFR concentrations in urine for three quarters of the OPFRs.Questionnaire answers and calculations indicated that differences in OPFR concentrations in urine were mainly caused by females spending much more time than males in dormitories.There was also gender disparity in concentration of dialkyl and diaryl phosphates(DAPs).This may explained by the reason that P450 enzymes affect the concentrations of OPFR oxidative metabolites in human urine,and there are dierences in P450 enzyme expression in males and females.The hazard quotience of PBDEs and OPFRs were compared.Although the concentration of PBDEs in the indoor dust were higher than OPFRs,OPFRs may pose similar degrees of health risk as PBDEs,and this must be considered when making decisions about controlling flame retardants.