Insight on reproductive effects in Japanese rice fish (Oryzias latipes) exposed to perfluorinated compounds
Korea Institute of Toxicology
Perfluorinated compounds (PFC), especially PFOA (perfluorooctanoic acid) and PFOS (perfluorooctanesulfonic acid) having 8 carbon chains (C8), are widely found in the environment due to their strong persistent property despite of the use restrictions because they induce the toxic effects such as endocrine disruptions. Recently, the alternative perfluorinated compounds with shorter carbon chains (C4 or C6) have been developed to replace PFOA and PFOS. However, not only the underlying mechanisms of PFOA and PFOS but also the toxic effects of the alternative PFCs have not been clarified. In current study, we exposed PFOA and PFOS to adult Japanese rice fish (Oryzias latipes) for 7, 14 and 21-days and estimated the reproductive effects including fecundity and transcriptional level of hepatic vitellogenin genes (vtg1 and vtg2) in male and female. To estimate the reproductive toxicity of shorter alternative PFCs, moreover, we exposed perfluorobutanoic acid (PFBA, C4), perfluorohexanoic acid (PFHxA, C6) and PFOA to O. latipes during three generation (F0 to F2), the reproductive effects such as fecundity, 2nd sex characterization, gonadosomatic index (GSI), spawning time and hatching rate were observed. As a results, in 21-days study, the fecundity of fish exposed to PFOA and PFOS was reduced but no change in number of anal fin papillary was observed. PFOA increased the transcriptional level of vtg1 in both male and female whereas PFOS decreased that of vtg1 in male. The transcriptional change was not time-dependent. In generation study, PFHxA and PFOA affected fecundity, gonadosomatic index, spawning time at F1 generation and hatching rate at F2 generation. However, no significant change was found in histological observation of gonad. The results of this study provided insights on the reproductive effects of both conventional and alternative PFCs.