Biioaccumulation Of Polybrominated Diphenyl Ethers In Amphibians, And The Comparison With Aquatic And Terrestrial Animals

Polybrominated diphenyl ethers (PBDEs) are wildly used as brominated flame rerardants. Due to their bioaccumulation and extensive toxicity, PBDEs have received much attention. Many studies reported the bioaccumulation and distribution of PBDEs about aquatic and terrestrial species, but the information about amphibian was limited Taizhou, an area of Zhejiang Province, is one of the largest e-waste recycling areas in China, and the irrational recycling activities have led to the release of PBDEs into the surrounding environment. To illustratethe characteristics of bioaccumulation and distribution of PBDEs in frogs, we collected various frogs in this region and measured PBDEs contents by GC-MS.The result shows that the values of PBDEs concentrations in the frog tissues ranged from 2.62 to 501.20 ng/g wet wt, at a higher content level. The trend for∑PBDEs concentrations was ovary>liver>testis>brain, on the wet wt basis. All the PBDE congeners were detected in various frog tissues, with BDE-47,99 and 153 as the largest contributors, constituted at least 80% of the total PBDE concentrations. Different tissues of one frog species exhibited a similar PBDE congener profile, but between different kinds of frogs there are some differents.To compare the bioaccumulation and distribution of PBDEs in amphibians and aquatic and terrestrial species, we also detected the PBDEs in aquatic and terrestrial species samples. The PBDE congener profiles in amphibians differed from those in the pollution background in this area and in the terrestrial species, which were characterized by higher brominated diphenyl ethers as dominated congeners. However, the PBDE congener profiles in amphibians were similar to those in aquatic species, while were characterized by lower brominated diphenyl ethers as dominated congeners. Because BDE-47 was the largest contributors in aquatic species, PBDEs bioaccumulation in amphibians was also different from aquatic animals.In the experiment of debromination and elimination of BDE-209, the result showed that the effect of debromination and elimination in mouse was stronger that in Xenopus laevis and zebra fish. The mouse and Xenopus laevis had a similar pattern of debromination and elimination of BDE-209, during the first 10 days, many new PBDEs congeners were generated by the debromination of BDE-209, and then dominated by elimination effect, all the congeners decreased with time. To zebra fish, the new PBDEs congeners reached the maximum concentration at the 20 days, and then there has been a strong debromination during the whole elimination period, and the congeners concentrations remain basically unchanged with time. The results suggested that there were differences in the debromination and elimination of BDE-209 in amphibians, aquatic and terrestrial animals, and these could also explain the reasons for the different of PBDEs congenerpatte rn in different animals.