Influence of Heavy Metals and Surfactants on the Adsorption of Tetracyclines to Sediment

摘要

The widely utilization of pharmaceutical and personal care products (PPCPs) in the pharmaceutical therapies and agricultural husbandry has led to the world pollution. Thus, it is of great interest to study the mobility and fate of PPCPs in the environment. The aim of this study was to investigate the influence of heavy metal Pb(II), anionic surfactant sodium dodecylbenzenesulfonate (SDBS), nonionic surfactant Triton X-100 (TX-100) on the adsorption of representative PPCPs (tetracycline (TC) and oxytetracycline (OTC) on two types of adsorbents. Results showed that the adsorption isotherms of TC and OTC on two sediments were in good comparison with Freundlich equation. However, compared to the sediment B without organic matter (OM), the sediment A with higher OM exhibited the higher adsorption affinity to TC and OTC. The presence of Pb (II) caused a significant increase on the TC and OTC adsorption to sediment A due to the formation of ternary complex between OM ligand groups and tetracycline ligandgroups. However, the influence of Pb (II) on TC and OTC adsorption on sediment B was minimal. The presence of SDBS increased TC and OTC adsorption on two sediments, which could be due to the significantly increasing OM content of two sediments via the SDBS adsorption. In contrast, the nonionic surfactant TX-100 caused a slight reduction on TC and OTC adsorption on two sediments even at high concentration.