Institute of Quality Standard and Monitoring Technology for Agro-Products, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Quality & Safety Risk Assessment for Agro-Products, Guangzhou 510640, China; Laboratory of Quality & Safety Risk Assessment for Agro-Products (Guangzhou), Ministry of Agriculture and Rural Affairs, Guangzhou 510640, China.
CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
J Hazard Mater. 2023 Aug 5;455:131640. doi: 10.1016/j.jhazmat.2023.131640. Epub 2023 May 15.
Chlorinated paraffins (CPs) are emerging environmental pollutants. Although metabolism has been shown to affect the differential accumulation of short-chain (SCCPs), medium-chain (MCCPs) and long-chain (LCCPs) CPs in birds, CP metabolites have rarely been reported and the extent to which they are formed is still unclear. In this study, single and mixed CP standards were incubated with chicken liver microsomes in vitro to study the generation of CP metabolites. Putative aldehyde/ketone and carboxylic acid metabolites identified by mass spectroscopy data were shown to be false positive results. Phase I metabolism of CPs first formed monohydroxylated ([M-Cl+OH]) and then dihydroxylated ([M-2Cl+2OH]) products. The yields of monohydroxylated metabolites of CPs decreased with increasing carbon chain length and chlorine content at the initial stage of reaction. Notably, the yield of monohydroxylated metabolites of SCCPs with 51.5% Cl content reached 21%, and that of 1,2,5,6,9,10-hexachlorodecane (CHCl) was as high as 71%. Thus, monohydroxy metabolites of CPs in birds should not be ignored, especially those of SCCPs. This study provides important data that could support improvements to the ecological/health risk assessment of CPs.
氯化石蜡（CPs）是新兴的环境污染物。尽管代谢已被证明会影响鸟类中短链（SCCPs）、中链（MCCPs）和长链（LCCPs）CPs 的差异积累，但 CP 代谢物很少被报道，其形成程度仍不清楚。在这项研究中，使用鸡肝微粒体在体外孵育单和混合 CP 标准品，以研究 CP 代谢物的生成。通过质谱数据分析鉴定出的醛/酮和羧酸代谢物被证明是假阳性结果。CPs 的 I 相代谢首先形成单羟基化（[M-Cl+OH]）产物，然后形成二羟基化（[M-2Cl+2OH]）产物。在反应的初始阶段，CPs 单羟基化代谢物的产率随碳链长度和氯含量的增加而降低。值得注意的是，氯含量为 51.5%的 SCCPs 的单羟基化代谢物的产率达到 21%，而 1,2,5,6,9,10-六氯癸烷（CHCl）的产率高达 71%。因此，鸟类中 CP 的单羟基代谢物不应被忽视，尤其是 SCCPs 的单羟基代谢物。这项研究提供了重要的数据，有助于改进 CPs 的生态/健康风险评估。
