Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.
Environ Sci Technol. 2010 Jul 15;44(14):5655-60. doi: 10.1021/es101158e.
Recent reports indicate that decabromodiphenyl ethane (DBDPE) has become widespread in the environment. Yet databases regarding its bioavailability, biotransformation, and possible toxic effects to wildlife and humans are lacking. In this study, we investigated the bioconcentration and biotransformation of DBDPE after oral exposure and compared the results with those of decabrominated diphenyl ether (BDE-209) using rats as a model. Male rats were orally administrated with corn oil containing 100 mg/kg bw/day of DBDPE or BDE-209 for 90 days, after which the levels of DBDPE and BDE-209 in the liver, kidney, and adipose were measured. Biochemical parameters, including thyroid hormone levels, 13 clinical chemistry parameters, and the mRNA expression levels of certain enzymes were also monitored. Results showed DBDPE was found in all tissues with concentrations 3-5 orders of magnitude lower than BDE-209. At least seven unknown compounds were observed in the DBDPE-exposed rats, indicating that DBDPE biotransformation occurred in rats. These compounds were identified by comparing relative retention times and full-scan mass spectra of DBDPE debrominated products from a photolytic degradation experiment using GC/EI-MS and GC/ECNI-MS analysis. The results showed that debromination of DBDPE to lower brominated BDPEs were not the primary metabolic pathway observed in rats. Two of the metabolites were proposed tentatively as MeSO(2)-nona-BDPE and EtSO(2)-nona-BDPE using GC/EI-MS, but their structures require further confirmation by other techniques and authentic standards. In addition, evidence of a biological response to DBDPE and BDE-209 and their metabolites in rats are different. To our knowledge, these results are the first indications for the biotransformation of DBDPE in biota. Further studies are necessary to investigate the metabolites of DBDPE and their mechanisms of toxicities to assess the potential risks of DBDPE.
最近的报告表明，十溴二苯乙烷（DBDPE）已经在环境中广泛存在。然而，有关其生物利用度、生物转化以及对野生动物和人类可能产生的毒性影响的数据库还很缺乏。在这项研究中，我们研究了 DBDPE 在口服暴露后的生物浓缩和生物转化，并使用大鼠作为模型，将结果与十溴二苯醚（BDE-209）进行了比较。雄性大鼠经口给予含 100mg/kg bw/day DBDPE 或 BDE-209 的玉米油，90 天后测量肝脏、肾脏和脂肪中的 DBDPE 和 BDE-209 水平。还监测了生化参数，包括甲状腺激素水平、13 项临床化学参数以及某些酶的 mRNA 表达水平。结果表明，DBDPE 存在于所有组织中，浓度比 BDE-209 低 3-5 个数量级。在 DBDPE 暴露的大鼠中观察到至少七种未知化合物，表明 DBDPE 在大鼠体内发生了生物转化。这些化合物通过比较光降解实验中 DBDPE 脱溴产物的相对保留时间和全扫描质谱，使用 GC/EI-MS 和 GC/ECNI-MS 分析进行鉴定。结果表明，DBDPE 脱溴生成低溴代联苯醚不是大鼠体内观察到的主要代谢途径。两种代谢物被推测为 MeSO(2)-nona-BDPE 和 EtSO(2)-nona-BDPE，使用 GC/EI-MS，但它们的结构需要通过其他技术和真实标准进一步确认。此外，DBDPE 和 BDE-209 及其代谢物在大鼠体内的生物学反应证据不同。据我们所知，这些结果是生物体内 DBDPE 生物转化的首次迹象。需要进一步研究来调查 DBDPE 的代谢物及其毒性机制，以评估 DBDPE 的潜在风险。
