Current contamination status of traditional and emerging persistent toxic substances in the sediments of Ulsan Bay, South Korea.

Contamination status of traditional and emerging persistent toxic substances (PTSs) in sediments and their major sources were investigated in Ulsan Bay, Korea. A total of 47 PTSs, including 15 traditional PAHs, ten styrene oligomers (SOs), six alkylphenols (APs), and 16 emerging PAHs (E-PAHs) were analyzed. Concentrations of traditional PAHs, SOs, and APs ranged from 35 to 1300 ng g⁻¹ dry weight (dw), 30 to 3800 ng g⁻¹ dw, and 30 to 430 ng g⁻¹ dw, respectively. For the last 20 years, PTSs contamination in the bay area has been improved. However, 12 E-PAHs were widely detected in sediments, with a maximum of 240 ng g⁻¹ dw (for benzo[ e ]pyrene) at the creek site. These E-PAHs seemed to originate from surrounding activities, such as biomass combustion, mobile sources, and diesel combustion. Due to environmental concerns for E-PAHs, further research on the potential toxicity, distribution, and behavior of these compounds should be implemented. Unlabelled Image • Contamination levels of PTSs in sediments have decreased during the last decades. • The major source of PAHs has changed from petroleum sources to combustion origins. • E-PAHs were widely distributed in the sediments, originating from surrounding activity. • E-PAHs have some potential toxicity; thus, further research should be implemented. [ABSTRACT FROM AUTHOR]