A congener-specific survey for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) contamination in Masan Bay, Korea

A congener-specific determination of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in 21 surface sediments from Masan Bay, Korea revealed that the most toxic 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) was detected in 76% of the samples and 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF) in 100% of the samples analyzed. The concentration range of ΣPCDDs and ΣPCDFs are: 230–6900; 120–16 700 pg g−1 dry mass respectively. WHO Toxic Equivalents (WHO-TEQ) in Masan Bay sediment ranged from 0.53 to 99 ng TEQ kg−1 d.m. for PCDDs; 4 to 1300 ng TEQ kg−1 d.m. for PCDFs. In comparison with an earlier survey, the concentrations of dioxins and furans have more than doubled and the ΣWHO-TEQ values have increased 15 times within a decade. Both point and non-point sources of pollution are suspected, especially, local sewage treatment plants are found to contribute.