State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, PR China.
Chemosphere. 2012 Feb;86(5):446-53. doi: 10.1016/j.chemosphere.2011.09.038. Epub 2011 Oct 27.
Polybrominated diphenyl ethers (PBDEs) are extensively used as a class of flame retardants and have become ubiquitous environmental pollutants. Significant biotransformation of some PBDEs via reductive debromination has been observed. However, little is known about the fate of lower brominated BDEs in fish. In this study, the tissue distribution, excretion, depuration and biotransformation of 4,4'-dibromodiphenyl ether (BDE 15) were investigated in crucian carp (Carassius auratus) which were exposed to spiked water solution at different concentrations for 50d, followed by a 14-d depuration period. Bioaccumulation parameters were calculated and the results showed that BDE 15 was mainly concentrated in the gill and liver. In particular, five biotransformation products of BDE 15 in carp were identified using GC-MS/MS. Besides two debrominated metabolites, three of the metabolites were mono-OH-BDE 15, diOH-BDE 15 and bromophenol. Our results unequivocally suggested that BDE 15 oxidation did occur via the formation of hydroxylated (OH-) metabolites in crucian carp exposed in vivo. These findings will be useful for determination of the metabolic pathways of PBDEs in freshwater fish, especially about their oxidation metabolism.
多溴联苯醚（PBDEs）被广泛用作一类阻燃剂，已成为无处不在的环境污染物。已经观察到一些 PBDEs 通过还原脱溴作用发生了显著的生物转化。然而，关于鱼类中低溴化 BDEs 的命运知之甚少。在这项研究中，鲫鱼（Carassius auratus）暴露于不同浓度的加标水溶液中 50d 后，进行了 14d 的净化期，研究了 4,4'-二溴二苯醚（BDE 15）的组织分布、排泄、净化和生物转化。计算了生物积累参数，结果表明 BDE 15 主要集中在鳃和肝脏中。特别是，使用 GC-MS/MS 在鲤鱼中鉴定了 BDE 15 的五种生物转化产物。除了两种脱溴代谢物外，三种代谢物为单-OH-BDE 15、二-OH-BDE 15 和溴酚。我们的研究结果明确表明，在体内暴露的鲫鱼中，BDE 15 通过形成羟基化（OH-）代谢物发生氧化。这些发现将有助于确定淡水鱼中 PBDEs 的代谢途径，特别是它们的氧化代谢。
