Steroids, renowned for endocrine-disrupting capabilities, have garnered significant research interest, predominantly centered on their parent forms. This study was the first to explore the composition, spatiotemporal characteristics, sources, mass inventories, and ecological risks of steroids in free and conjugated forms in estuarine sediments. Seventeen steroids were identified in sediments with the total levels of 1.3–4.3 ng/g. Most natural steroids and metabolites existed in free forms, while synthetic ones predominantly stored in conjugates. Environmental factors exerted limited impacts on steroid distribution. Raw domestic wastewater, drug consumption, and mariculture may be leading steroid sources in estuarine sediments, with total mean mass inventories of 177–219 μg/m2. The predominant contributors to the ecological risk were cortisol, prednisolone, 20α-dihydroprogesterone, 20β-dihydroprogesterone, and progesterone. This research gives the first insight into the understanding of conjugated steroids in the marine environment, and advocates for more studies on the fate and ecotoxicology of conjugated steroids.

中文翻译：

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共轭类固醇的普遍存在和生态风险不容忽视：来自河口沉积物的第一个证据


类固醇以其内分泌干扰能力而闻名，引起了人们的广泛研究兴趣，主要集中在其母体形式上。这项研究首次探讨了河口沉积物中游离和共轭形式类固醇的组成、时空特征、来源、质量库存和生态风险。在沉积物中鉴定出 17 种类固醇，总含量为 1.3–4.3 ng/g。大多数天然类固醇和代谢物以游离形式存在，而合成类固醇和代谢物主要以缀合物形式存在。环境因素对类固醇分布的影响有限。原始生活废水、药物消耗和海水养殖可能是河口沉积物中类固醇的主要来源，总平均质量库存为 177–219 μg/m2。生态风险的主要贡献者是皮质醇、泼尼松龙、20α-二氢孕酮、20β-二氢孕酮和黄体酮。这项研究首次深入了解了海洋环境中的共轭类固醇，并提倡对共轭类固醇的命运和生态毒理学进行更多研究。