The Cytotoxic and genotoxic effects of di-isononyl phthalate and di-(2-ethylhexyl) phthalate: An in vitro and in vivo approach on toxicological assessment

Abstract

The aim of the present study was to analyze the cytotoxic and genotoxic effects of two selected phthalates, di-isononyl phthalate (DINP) and di-(2-ethylhexyl) phthalate (DEHP) in vivo and in vitro using fish model, Oreochromis mossambicus and cell lines as Chinese Hamster Ovary-K1 (CHO-K1) cells, TA97A, TA98 and TA100 strains of Salmonella typhimurium and human peripheral erythrocytes. In vivo toxicological assessment showed genotoxicity of DINP and DEHP at 300 ppm and 60 ppm concentrations exposed for 60 days, which was evident by the formation of micronuclei and other nuclear abnormalities in erythrocytes of the fish. However, comet analysis revealed no genotoxic effects of the phthalates in which tail length and percent tail DNA remained unchanged. In vitro analysis showed mutagenicity of DINP and DEHP in Salmonella typhimurium tester strains. Study on human peripheral blood lymphocytes showed the formation of micronuclei, nucleoplasmic bridges and nuclear bud. Exposure of phthalates in CHO-K1 cells showed significant (P<0.05) increase in the tail length and tail DNA percent in DEHP while DINP showed negative results. Cell viability test using MTT assay in CHO-K1 cells showed significant (P<0.05) decrease in cell viability while lactate dehydrogenase release test showed cytotoxicity of exposed phthalates. The study illustrated that DINP and DEHP exerted genotoxic effects both in vivo and in vitro could be relatively unsafe for the organisms. Further, the study can be used as a biomonitoring tool to alarm the risk of plasticizers that enter into the aquatic or nearby environment from the production or release sites.