Toxic effects of phenolic metabolite 6-OH-BDE 85 on zebrafish (Danio rerio) embryos

Abstract

The hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are important metabolites formed by in vivo metabolism of brominted diphenyl ethers and a natural product produced by marine organisms such as algae, so such ethers are ubiquitous in the environment. 6-OH-BDE 85 is a type of such metabolites. In order to monitor both general toxicity as well as teratogenicity of this compound, embryos of zebrafish were exposed to gradual concentrations (0.03, 0.1, 0.3, 1 and 2.5 μM) of 6-OH-BD 85. After 24, 48, 72 and 96 hrs of exposure, general morphology and teratogenic effects were recorded. Both the general morphology score and the teratogenecity score were analyzed. Results showed that the doses 1 and 2.5 μM were lethal when examined at 24 hs post fertilization (hpf) while the dose 0.3 μM caused developmental retardation and deformation at 48 hpf and global death at 96 hpf. This study shows that such metabolites should be included in the ecotoxicological studies for a proper risk assessment and more attention should be given to this class of chemicals in the aquatic environment.