title: Sorption and degradation of wastewater-associated pharmaceuticals and personal care products in agricultural soils and sediment.
abstract: 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.
authors.affiliation: 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: hxch88@yahoo.com.cn.
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Wu
authors.forename: Na
authors.initials: N
authors.lastname: Sun
authors.forename: Yong
authors.initials: Y
authors.lastname: Ye
authors.forename: Huaixia
authors.initials: H
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D002110:Caffeine / Q000737:chemistry; D002681:China; D002701:Chloramphenicol / Q000737:chemistry; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D008795:Metronidazole / Q000737:chemistry; D045483:Rivers; D012989:Soil Pollutants / Q000737:chemistry*; D014011:Tinidazole / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D014011:Tinidazole; D008795:Metronidazole; D002110:Caffeine; D002701:Chloramphenicol