In Vitro Study On The Toxicity Of Polybrominated Diphenyl Ethers

Polybrominated diphenyl ethers (PBDEs) have been extensively used as brominated flame retardants (BFRs) in plastics, textiles, electronic appliance, building materials and other materials to reduce flammability.Sufficient evidence showed that PBDEs have been rapidly accumulated in the environment and biomagnified in the food chains.Thus, the heath risk caused by PBDEs is paid more and more attention by the scientists and the public all over the world.Humans exposure to PBDEs mainly through foods,indoor air,etc.Levels of PBDEs in the environment and human body increased significantly in last 30 years.Laboratory data showed that PBDEs exposure could disturb endocrine function such as thyroid and sex hormone.But the research on the toxicity to liver,nervous system,immune system, reproduction and human development is far more less.Meanwhile, the former studies were mainly done by in vivo researches.The high dose could not reveal the toxicity in the environmental exposure level.But due to the development of the in vitro studies, primary-cultured cells were applied to estimate the toxicity caused by environmental pollutions.In this study, the environmental doses were used to estimate the toxicity of PBDEs on the endocrine, immune and reproduction systems in vitro.To estimate the endocrine toxicity of PBDEs, vitellogenin (VTG), an estrogen-controlled gene expression, was used as an endpoint in this study.The results showed 1 ng/L-1000 ng/L BDE47 suppressed the expression of VTG-mRNA. And BDE209 suppressed the expression of VTG-mRNA at 1 ng/L, while stimulated the expression at 1000 ng/L, acted as either estrogenic agonist or antoagonist at different doses showed a biphasic dose response.The equipotent binary mixture of BDE47 and BDE209 suppressed the expression as BDE47 did but had a synergic effect at 10 ng/L and 100 ng/L.To estimate the immune toxicity of PBDEs,the lymphocyte from cord blood was used. The results showed 1μg/L-100μg/L BDE47 significantly decreased the percentage of lymphocyte subset CD3-CD19+,CD3-CD23+,CD3-CD16+CD56+.And BDE209 decreased the percentage of lymphocyte subset CD3-CD19+at 1μg/L, while increased at 100μg/L, showed a biphasic dose response. And as a kind of high-brominated PBDEs, BDE209 decreased the percentage of CD3-CD16+CD56+,CD3-CD23+To estimate the reproduction toxicity of PBDEs, the human sperm was used in the experiment. The results showed both BDE47 and BDE209 suppressed the motility of sperm significantly at the dose ranging from 1μg/L to 100μg/L, and the motility of sperm was suppressed along with the time.According to the above, this study was based on in vitro research. The endpoints were sensitive to PBDEs, and had certain physiological meanings.It concluded that the endocrine system, immune system, and reproduction system were disturbed by PBDEs at low dose. And the results provided the references to estimate the toxicity of PBDEs.