Teratogenicity, cardiac toxicity, neurotoxicity and genotoxicity in zebrafish embryo-larvae exposed to 4-bromodiphenyl ether.

Polybrominated diphenyl ethers (PBDEs) have been classified as a new class of persistent organic pollutants by the United Nations Environment Programs in 2009. In environment, PBDEs can undergo the degradation process to form less brominated diphenyl ethers. In the present study, the 96 h LC₅₀ value for 4-bromodiphenyl ether (BDE-3) was found to be 3.18 mg/L in zebrafish embryo-larvae. Further, zebrafish embryo-larvae was exposed to sublethal concentrations i.e. 0.79 mg/L and 1.59 mg/L of BDE-3 to evaluate the developmental toxicity. BDE-3 significantly increased the mortality rate and decreased hatchability rate in a concentration and time-dependent manner at sublethal concentrations compared to control. Heart rate was found to be significantly decreased whereas the sinus venosus- bulbus arteriosus (SV-BA) distance found to be significantly increased in both BDE-3 exposed groups. The sensorimotor response and spontaneous movement were significantly decreased in BDE-3 exposed larvae compared to control group. A significant DNA damage was also found to be caused in BDE-3 exposed groups after the acute exposure. The current report highlights the toxicity potential of BDE-3 in the early life stages of zebrafish and hence puts up to their environmental risk assessment.