Study On Toxic Effects And Mechanisms Of Low-dose Exposure UV-filters And Perfluorinated Compounds

Organic UV filters(UV filters)are widely used in sunscreen,hair care products,detergents and other personal care products.Perfluorinated compounds(PFCs)are ubiquitously added in oil-repellent,water repellent,anti-lipid agents,surfactants agent,etc.Both of them are typical emerging contaminants which were frequently detected in indoor air and dust in widespread scale.Human being could take in those compounds in long-term exposure through different pathways.However,to date,there are rare reports on their health effects through respiratory exposure.In this paper,5 typical UV filters and 5 PFCs were evaluated,including UV filters 2-hydroxy-4methoxy benzophenone(BP-3),4-methylben-zoylmethane(BP-4),octocrylene(OC),Octyl 4-methoxycinnamate(EHMC),butyl methoxydibenzoylmethane(BM-DBM),and PFCs perfluorooctane sulfonate(PFOS),perfluorooctanoic acid(PFOA),perfluorononanoic acid(PFNA),perfluoroheptanoic acid(PFHpA),perfluorohexane sulfonate(PFHxS).Human embryonic lung fibroblasts(MRC-5)were selected to investigate their celluar toxic effects and mechanisms,in a relatively low dode exposure levels.Methods were as followed.(1)Cell culture and Cytotoxicity assayMTT(diphenyltetrazolium bromide)assay were used to test cell viability.(2)Effects of UV filters and PFCs on the antioxidant systemThe activities of superoxide dismutase(SOD),catalase(CAT),the content of glutathione(GSH),malondialdehyde(MDA)and reactive oxygen species(ROS)were tested.(3)Effects of UV filters and PFCs on P-glycoprotein functionRodamine-123 assay were using to detect the effect of multixenobiotic resistance mechanism.Results:(1)All the 24 hour acute exposures of UV filters and PFCs resulted in significant effects on the cell viability of MRC-5;particularly,UV filter BP-3 and all the PFCs showed hormesis effect in an environmentally relevant levels.In addition,high level exposure of UV filters and PFCs could depressed the cell viability obviously.Overall,there is no unambiguous trends as concentration-response relationship between the dose of UV filters or PFCs and the cell viability.(2)As to effects of UV filters on the antioxidant system of MRC-5 cell,BP-3,EHMC and OC induced SOD activities significantly,while CAT activities decresed in all UV filters treatment groups.EHMC and OC casued significant difference in antioxidant system,especially in environmentally revelant concentration,high concentration BP-3 also caused obvious difference in antioxidant system.In all UV filters exposure groups,ROS levels increased(P<0.05)and GSH levels decreased,besides,there were no discipline in change of MDA content.Antioxidant system were also influenced in all PFCs exposure groups.PFOA induced SOD activities significantly,while SOD activities were inhibited at low target compound exposures in other PFCs groups.CAT activities were affected differently in all PFCs treat groups.Significant difference were observed in PFOS,PFNA,PFHxS at environmentally recelant concentration and PFOA at high concentration(100?mol/L)groups.In all PFCs exposure groups,ROS levels were increased(P<0.05),although the contents of GSH and MDA were not significantly changed.(3)All the UV filters and PFCs had adverse effects on MXR mechanism at the concentration of 1,10,100?mol·L-1.Further study are needed to explain the reason.