Organophosphate Flame Retardants In Indoor Air,Particulate Matters And Dust

Organophosphate flame retardants(PFRs)are commonly used as flame retardants,which are applied in a varidy of commercial products,including building matierials,electronics,textiles,paints,and floor polishes.Since PFRs have toxic effects on living organisms,and been added to products directly,thus these substances can be easily diffused into surrounding environments and result in adverse effects.Researchers in China mostly focus on the synthesis,performance and optimization of PFRs.However,few literatures on pollution characterazition and human exposure in the environments,especially in the indoor environments have been reported.Dust samples from 30 homes,33 offices and 10 daycare centers,and particulate matters(PM)and air samples from 9 homes,10 offices and 4 daycare centers were collected in Beijing to investigate the characteristics of PFRs.Among which,1 office and 1 home were selected to collect samples semimonthly over a year to examine the temporal trend.Dust samples exhibited high PFRs levels in three locations with office>home>daycare center.Tris(2-chloroethyl)phosphate(TCEP)was the most important PFRs in home dust and daycare center dust,while tris(2-chloroisopropyl)phosphate(TCIPP)was the most abundant PFRs in office dust.There was significant seasonal variation in office dust samples with winter higher than summer,while no temporal trend was observed in home dust samples over a year.PFRs in fine particulate matter(PM2.5),inhalable particulate matter(PM10)and total suspended particulate matter(TSP)were analyzed.Similar to dust samples,office'and home' had higher PM PFRs than daycare center'.The most abundant PFRs in home and daycare center PM was TCEP,and TCIPP was the most abundant PFRs in the daycare center.There was significant seasonal variation in office PFRs in different PM samples with winter lower than summer,while no temporal trend was observed in home PM samples.PFRs in air samples exhibited higher levels in offices and homes than those in daycare centers.TCEP was the most important PFRs in air in offices and daycare centers.Due to higher vapor pressure,TEP was the most abundant one in homes.Unexpectedly,there were no seasonal variations in air samples both from the office and the home.There were significant correlations between levels from air,PM and dust,indicating they had similar sources in indoor.Finally,we used the measure levels from different matrixes to estimate human exposure(toddlers,adults and the elderly)to PFRs through air inhalation,PM(PM10)inhalation and dust ingestion.PM inhalation seems to be the major exposure pathway for PFRs with estimated daily uptakes higher than those from air inhalation and dust ingestion.Adults had the highest estimated daily exposure to(?)PFRs,followed by the elderly and toddlers.However,after normalized to body weight,the toddlers had the highest exposure,followed by the elderly and adults.