环境水体中糖皮质激素及其生物转化产物的识别与转化机理研究

Glucocorticoid (GCs) is an important class of environmental endocrine disrupting chemicals and emerging contaminants, which can induce ecological harm by interfering with the endocrine system at extremely low concentrations. However, comparing with estrogens, it is very weak of numerous GC compounds concerning their circulation characteristics and environmental behavior in surface water. There is no much data about pollution characteristics and biotransformation mechanism of toxic GC metabolites. Because of the very low environmental concentrations, the key issue of the study is to identify numerous GCs and their metabolites from the complex matrix. Thus, the present study will firstly develop methods for identifying these GC compounds by using advanced UPLC-QTOF-MS and UPLC-MS/MS technology combined with the optimized enrichment and purification process. Secondly, to investigate the effects of various environmental factors on the microbiological degradation of target GCs under aerobic conditions, and suggest the biotransformation pathways and mechanism by identifying the transformation products. Thirdly, to identify the types and distribution levels of GCs and their metabolites occurring in different environmental waters, and explore the transformation behavior in natural surface waters. The results obtained from this work will help understand the environmental and biogeochemical behavior of GCs, and provide scientific basis for risk assessment and pollution control in the environment.

糖皮质激素(GCs)是一类重要的内分泌干扰物质(EDCs)和新型污染物(ECs)，在极低浓度下就能干扰内分泌系统诱发生态危害。然与雌激素相比，众多GCs化合物在地表水环境中的循环特征和环境行为研究还非常薄弱，具有毒性效应的生物转化产物的环境污染特征和生物转化机制尚不清楚。因环境浓度极低，从复杂基质中识别众多GCs及其转化产物是研究的关键。项目拟在优化富集纯化过程的基础上联合运用高灵敏UPLC-MS/MS和高精度UPLC-QTOF-MS技术、建立识别和鉴定的有效方法；研究不同水质条件等环境因素GCs微生物降解转化过程的影响规律，阐明化学、生物学因素耦合作用下的转化途径和机理；揭示不同环境水体中GCs的赋存种类、形态及其时空分布差异，探索环境GCs与转化产物的生物转化机制及主要影响因素，弥补对EDCs/ECs环境与生物地球化学行为认识的不足，为其环境污染风险评估和控制提供科学依据。

类固醇激素是备受关注的内分泌干扰物质，但是相关的环境研究主要集中在少数几种雌激素和雄激素，而通过天然排泄以及药物使用进入环境中的天然和合成糖皮质激素、孕激素和盐皮质激素及其降解转化产物种类超过数百种、且可能具有生态健康风险，它们在水环境中的污染和迁移转化研究却非常薄弱。鉴于这样的现状，本项研究针对糖皮质激素、孕激素和盐皮质激素开展，主要获得以下进展：①开发了环境多介质中糖皮质激素、孕激素、盐皮质激素等136种类固醇激素及其降解转化产物的高灵敏检测方法；②通过污水处理质量平衡分析，发现孕、糖皮质激素易于生物降解，降解前后组分呈现显著差异，提出水环境糖皮质激素是可以指示未处理污水排放的新型分子标记物。③在国际上首次报道了39种天然/合成糖皮质激素和孕激素的环境污染，发现的天然孕烷醇酮比传统关注的孕酮浓度高60倍，且新型卤代衍生物是北京水体中糖皮质激素效应的主要贡献物质。以通讯作者在环境领域权威期刊发表SCI论文6篇，平均影响因子8.067。