Analysis on the attenuation characteristics of PPCPs in surface water and their influencing factors based on a compilation of literature data

Roujia Du; Lei Duan; Qianxin Zhang; Bin Wang; Jun Huang; Shubo Deng; Gang Yu

doi:10.1016/j.watres.2023.120203

Analysis on the attenuation characteristics of PPCPs in surface water and their influencing factors based on a compilation of literature data

Water Res. 2023 Aug 15:242:120203. doi: 10.1016/j.watres.2023.120203. Epub 2023 Jun 9.

Authors

Roujia Du¹, Lei Duan¹, Qianxin Zhang¹, Bin Wang¹, Jun Huang¹, Shubo Deng¹, Gang Yu²

Affiliations

¹ State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, School of Environment, Tsinghua University, Beijing 100084, China.
² State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, School of Environment, Tsinghua University, Beijing 100084, China; Advanced Interdisciplinary Institute of Environmental and Ecology, Beijing Normal University, Zhuhai 519000, China. Electronic address: 11112022018@bnu.edu.cn.

PMID: 37336183
DOI: 10.1016/j.watres.2023.120203

Abstract

The attenuation characteristics of PPCPs play an important part in predicting their environmental concentrations. However, considerable uncertainty remains in reported laboratory data on the attenuation characteristics of PPCPs. In this analysis, we compile information on laboratory-observed photodegradation half-lives (t_1/2), biodegradation t_1/2, the organic carbon normalized adsorption constant (K_OC) and field-observed overall attenuation t_1/2 for PPCPs in water bodies from more than 200 peer-reviewed studies. To mitigate the effects of such uncertainty, we derive representative values (RV) for PPCP degradability from these records to better compare the characteristics of different PPCPs. We further examine the influence of experimental conditions and environmental drivers on the determination of t_1/2 using difference analysis and correlation analysis. The results indicate that for laboratory photodegradation tests, different light sources, initial concentration and volume significantly affect t_1/2, whereas there is no significant difference between values obtained from tests conducted in pure water and natural water. For biodegradation, laboratory-measured t_1/2 values in batch, flume and column studies gradually decrease, marking the controlling role of experimental setup. Redox condition, initial concentration and volume are also recognized as important influencing factors. For adsorption, water-sediment ratio is the primary reaction parameter. As two frequently investigated factors, however, pH and temperature are not significant factors in almost all cases. In field observations, the persistence of carbamazepine, typically used as a tracer, is in doubt. Water depth and latitude are the most correlated drivers of t_1/2, indicating the predominant status of photodegradation in the overall attenuation rates. These findings call for caution when selecting experimental parameters and environmental drivers in determining PPCP's attenuation rates and establishing PPCP fate models in the field.

Keywords: Attenuation in water; Data compilation; Half-life; PPCPs.