Pollution Characteristics of Polybrominated Diphenyl Ethers in Coastal Seawater of Dalian
Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants with environmental persistence, bioaccumulation, and toxicity, posing significant threats to marine ecosystems and human health. This study developed an analytical method using anhydrous sodium sulfate-alumina composite column chromatography coupled with gas chromatography-orbitrap mass spectrometry to quantify mono- to deca-BDEs in coastal seawater of Dalian, China. The total PBDE concentrations (∑PBDEs) ranged from not detected to 511.96 pg·L−1, with a mean of 163.96 pg·L−1. BDE-209 was the dominant congener, contributing 24.1% to ∑PBDEs. Spatial distribution exhibited distinct heterogeneity, with higher abundances of highly brominated PBDEs near sewage discharge outlets. Partial least squares discriminant analysis indicated that anthropogenic activities, particularly sewage discharge, were the primary sources. Ecological risk assessment revealed extremely low risk, with the highest risk quotient of 0.013 for BDE-17. These findings provide baseline data for PBDE contamination in Dalian coastal waters and underscore the need for continued monitoring of emerging contaminants.