Evaluating the spatial distribution and source of phthalate esters in the surface water of Xingkai Lake, China during summer

Abstract

Increasing production and usage of phthalate esters (PAEs) has made them ubiquitous in the environment. In this study, the distribution and source of PAEs in the surface water of Xingkai Lake, China were analyzed. The concentration of ΣPAEs in the water of Xingkai Lake ranged from 0.26 to 3.83 μg/L with a median of 1.28 μg/L. It was observed that the difference in the concentration of ƩPAEs between the small and large Xingkai Lakes is not significant (p > 0.05). Agriculturally dominated land use types in the Xingkai Lake watershed may be mainly responsible for the occurrence of PAEs in this Lake. The distribution of butyl benzyl phthalate (BBP) in small and large Xingkai Lakes showed a significant difference (p < 0.05) which may be related to anthropogenic activities. ƩPAEs in the water of Xingkai Lake demonstrated significant positive correlations with the ratio of total nitrogen (TN) to concentration of TP (rp = 0.697, p < 0.01) and the concentration of suspended particulate organic matter (SPOM) (rp = 0.345, p < 0.05). These results further indicate that the concentration of nutrients from agricultural activity had an impact on the concentrations of PAE in the lakes. Furthermore, the more SPOM would lead to more suspension of PAEs in the water phase. The source analysis of PAEs showed that high molecular weight PAEs were dominant in the Xingkai Lake which may be arising from the combustion of plastics or from building materials and household furnishing.