Multimedia contamination characteristics, risk assessment, and source quantification of phthalates in the Shaying River Basin, China.

Abstract

Phthalates (PAEs), a class of typical endocrine-disrupting chemicals, have been widely detected in the environment due to their prevalent use as plasticizers in plastic products. This study investigates the multimedia contamination characteristics and potential ecological risks of PAEs in water, soil, and sediments of the Shaying River (SYR) Basin. A Geodetector model (GDM) was employed to identify the key drivers influencing the spatial distribution of PAEs, while factor analysis and the Positive Matrix Factorization (PMF) model were utilized to quantitatively apportion the potential sources of PAEs. Results revealed that the concentrations and spatial variation of PAEs were significantly higher in soil and sediments than in water, with distinct compositional profiles. Water samples exhibited a higher proportion of low-molecular-weight PAEs compared to soil and sediment, where high-molecular-weight PAEs prevailed to a lesser extent. Notably, among the 6 target PAEs, di-n-butyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) were uniformly the primary PAEs in water, soil, and sediment of the SYR Basin, posing higher ecological risks to algae, crustaceans, amphibians, and fish compared to the other 4 PAEs. The spatial distribution of PAEs in the SYR Basin was comprehensively influenced by land use, precipitation, human activities, and soil types. Key factors vary across media, but the interaction between popdensity and other variables significantly enhanced the interpretation degree, jointly shaping the PAEs distribution patterns. Primary sources of PAEs in the basin were sewage and wastewater discharges (37.0%), nonpoint industrial sources (36.4%), and domestic sources (25.6%).