Contamination Levels and Ecological Risk Assessment of Phthalate Esters (PAEs) in the Aquatic Environment of Key Areas of Taihu Lake

Abstract

To better understand phthalate esters (PAEs) pollution in key areas of Taihu Lake, water and sediment samples were collected for content analysis. The concentrations of ∑PAEs in water samples from wet, dry, and normal seasons ranged 1.6-11.2 μg·L-1 (mean:3.68 μg·L-1), nd-6.21 μg·L-1 (mean:1.3 μg·L-1), and nd-1.72 μg·L-1 (mean:0.48 μg·L-1), respectively. No differences were found between upstream and downstream samples. DEHP was the predominant component in water samples, whereas DBP exceeded the national surface water environmental quality standards. The total PAE concentration in the sediment ranged between 0.74 and 6.90 μg·g-1 (mean:2.64 μg·g-1), with DBP and DEHP the predominant PAEs. The risk quotient (RQ) results showed that DBP and DEHP contributed the most potentially adverse effects to the aquatic environment in the key areas. The contents of PAEs in sediment were all less than the ERLs, thus posing no significant threat to aquatic organisms. The overall level of PAEs in the study area was moderate compared to those in other areas, including rivers, lakes, and estuaries from cities worldwide. Industrial pollution and urban activities are the major sources of PAEs in the aquatic environment of key areas of Taihu Lake.