Genotoxicity Studies And Risk Assessment Of Typical Chemicals In Emerging Contaminants

The progress of human society and the development of technology have led to the emergence of more and more chemicals,which are discharged into various environmental media during their production and utilization.The discharged chemicals have potential hazard to ecosystem safety.UV filters and plasticizers are the two most and widely used chemicals.In the present study,the ingredients of UV filters BP,BP-1,BP-2,BP-3,BP-4,BP-6,BP-8,4-MBC and the plasticizers DEHP,DCHP,BPA were studied for their genotoxicity and ecotoxicity.The Salmonella typhimurium reverse mutation test(Ames test)and Daphnia magna acute toxicity test were carried out.to study these chemicals.The experiments include separating and mixed toxicity tests.The results provided new data to support the comprehensive toxicity assessment for emerging contaminants,and also provided toxicological basis for the formulating of safety standards and pollutant discharge standards of human-contact compounds.From the Ames test,the UV filters components of BP,BP-1,BP-3,BP-4,4-MBC,and the plasticizers DEHP,BPA showed positive mutagenic,but the UV filters BP-2 and the plasticizer DCHP were negative.From the acute toxicity test,the 48h-LC50 values of BP,BP-1,BP-2,BP-3,BP-4,BP-6,BP-8 and 4-MBC on D.magna were 7.63,17.23,52.81,1.10,47.47,12.50,3.74 and 0.54 mg/L,respectively;The 48h-LC50 values of DEHP and BPA on D.magna were 0.57 and 11.12 mg/L,respectively.Toxicity levels ranged from low toxicity to very high toxicity.In the mixed toxicity of Ames test,for UV filters,the mixture of BP and BP-1,the mixture of BP-3 and BP-4,the mixture of BP-6 and 4-MBC,the mixture of BP-6,4-MBC and BP-8 were positive mutagenic,and for plasticizers,the mixture of DEHP and BPA was also positive.The comprehensive mutagenic effects types were manifested as antagonism and synergy.In the mixed toxicity test of D.magna,the 48h-LC50 values of the mixture of BP and BP-1 was 46.51%,and the comprehensive toxic effect type was antagonistic.The 48h-LC50 values of the mixture of DEHP and BPA was 7.71% on D.magna,and the comprehensive toxic effect type was synergistic.The evaluation factor method(AF)was used to derive the predicted non-effect concentration(PNEC)of these chemicals.Then the risk commercial method was used to evaluate the ecological risk of the emerging pollutants in the water environment.The results showed that the UV filters and plasticizers in this study have varying degrees of ecological risk.In addition,these chemicals are biologically persistent and cumulative,which may cause long-term damage to the aquatic environment and threaten human health.Scientific standards and environmental standards are urgently needed to be established for scientific management.