Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials & Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, Wuhan 430062, China E-mail:
Water Sci Technol. 2013;68(5):991-8. doi: 10.2166/wst.2013.326.
Pharmaceuticals and personal care products (PPCPs) have drawn popular concerns recently as an emerging class of aquatic contaminants. In this study, adsorption and degradation of four selected PPCPs, metronidazole, tinidazole, caffeine and chloramphenicol, have been investigated in the laboratory using two agricultural soils in China and sediment from Changjiang River. Adsorption tests using a batch equilibrium method demonstrated that adsorption of all tested chemicals in soils could be well described with Freundlich equation, and their adsorption affinity on soil followed the order of chloramphenicol > caffeine > tinidazole > metronidazole. Generally, higher Kf value was associated with soils which had higher organic matter contents (except for caffeine acid in this study). Degradation of selected PPCPs in soils generally followed first-order exponential decay kinetics, and half-lives ranging from 0.97 to 10.21 d. Sterilization generally decreased the degradation rates, indicating that microbial activity played a significant role in the degradation in soils. The degradation rate constant decreased with increasing initial chemical concentrations in soil, implying that the microbial activity was inhibited with high chemical loading levels.
药品和个人护理品（PPCPs）作为一类新兴的水体污染物，近来受到了广泛关注。本研究采用批平衡法，通过实验室实验，分别以中国的两种农业土壤和长江底泥为研究对象，考察了四种典型 PPCPs（甲硝唑、替硝唑、咖啡因和氯霉素）在土壤中的吸附和降解特性。实验结果表明，所有被测试的化学物质在土壤中的吸附均可用 Freundlich 方程很好地描述，其在土壤中的吸附亲和力顺序为氯霉素>咖啡因>替硝唑>甲硝唑。一般来说，与土壤相比，具有较高有机质含量（本研究中除了咖啡因酸）的土壤具有更高的 Kf 值。所选 PPCPs 在土壤中的降解通常遵循一级指数衰减动力学，半衰期范围为 0.97 至 10.21 d。灭菌通常会降低降解速率，表明微生物活性在土壤中的降解中起着重要作用。降解速率常数随土壤中初始化学浓度的增加而降低，这意味着微生物活性受到高化学负荷水平的抑制。
