OPEs And PAHs In Indoor Air,Dust And Pet Hair: Levels,Partitioning And Potential Risks

Recently,with the development of urbanization and industrialization in China,the emission amounts of polycyclic aromatic hydrocarbons?PAHs?and organic flame retardants are increasing rapidly.Compared with the outdoor environment,the indoor environment tends to be more closed and impacted by human activities as well as the pollutants released from indoor decoration and building materials,which may pose a great threat to the heath of human and pets.The concentrations,compositions,potential sources,partitioning behavior,emission amounts and health risk of PAHs and organophosphate ethers?OPEs?in decoration materials and in indoor air,dust,and pet hair from two cities Dalian and Tongliao were investigated in this study.The concentrations and compositions of organophosphorus flame retardants?OPFRs?in various heat preservation materials from different brands and types in China were investigated,as well as their OPFR burdens and emission amounts.The average concentrations of OPFRs were 41.4±10.2,?7.1±4.0?×10⁴,and 56.3±19.3?g/g in phenolic foams?PF?,polyurethane foams?PUR?,and extruded polystyrene boards?XPS?,respectively.OPFRs in the PUR materials were³ orders of magnitude higher than those in the other two materials,suggesting that organophosphate esters were added as flame retardants?FRs?in the PUR materials.Obvious variations in the concentrations and compositions of OPFRs were discovered in those heat preservation materials due to their material types,brands,and fire-ratings,as well as contaminations.Tris?2-chloro-isopropyl?phosphate?TCIPP?was the most dominant OPFR with a range from 22.3?in PF?to 6.73×10⁴?in PUR??g/g,which emphasized that TCIPP was the most commonly used flame retardant additive in China.Based on the OPFR concentrations,OPFR emission rates,and application amounts of heat preservation materials,we calculated the total burdens of OPFRs in those materials and their emission amounts in China.The potential total burden of OPFRs in the completed new buildings of China in 2017 was estimated to be^2.37±1.11×10⁴ t,while the total emission of OPFRs from those new materials was³.19±1.65 t/y.As significant sources of OPFRs,the heat preservation materials used in exterior or interior walls may pose potential health risks to humans.We investigated the levels,compositions,and partitioning behaviors of OPEs and PAHs in indoor air,dust,and pet hair from North China,as well as their potential exposures for humans and pets.The mean OPE concentrations in the indoor air,dust,and pet hair samples were 52.1 ng/m³,3510 ng/g,and 1440 ng/g;while the mean PAH concentrations were 369ng/m³,6000 ng/g,and 22.6 ng/g,respectively.The matrix-air partitioning of OPEs and PAHs may reach equilibrium for compounds with octanol-air partition coefficients(logK_oa)between7 and 11 for dust and logK_oa<12 for pet hair.Correlation analysis suggested that pet hair could be used as a sentinel for the exposure to certain PAHs,e.g.,?PHE?or?FLA?,via exposure to indoor air,but that for other compounds pet hair may represent exposures from a variety of pathways.This work suggests that pet hair may be a better sentinel than air and dust for human exposure to OPEs and PAHs across different indoor microenvironments.Estimated daily intakes?EDIs?to OPEs and PAHs via air inhalation,dust ingestion,and dermal absorption were calculated for children,adults,and pets.The median?EDIs for children,adults,and pets were26.7,5.40,and 55.0 ng/kg/d for?OPEs,and 68.8,19.1,and 130 ng/kg/d for?PAHs,respectively.Air inhalation was the main exposure route for PAHs and OPEs with logK_oa<10,whereas dust ingestion was the main exposure route for those with logK_oa>10.