Distribution of Organohalogen Compounds in Surface Water and Sediments of Major River Systems Across South Korea

Abstract

In this study, we assessed the occurrence, levels, and distribution patterns of hexachlorocyclohexanes (α-, β-, and γ-HCHs), endosulfans (α- and β-endosulfan, and endosufan sulfate), polybrominated diphenyl ethers (PBDEs), and perfluorinated compounds (PFCs) in major water systems across South Korea. We studied water and sediment in four major rivers (Han, Nakdong, Keum, and Yeongsan Rivers), six smaller rivers, and four reservoirs in South Korea. Results showed that these organohalogen compounds were widely distributed throughout the country. Relatively high concentration of γ-HCH was observed at the downstream of the highly populated areas, which indicates the current use of lindane for medical purposes. High concentrations of PFCs and endosulfans in water might reflect the current input of PFCs to the water systems through the release from PFC-containing products and the recent extensive use of endosulfans for pest control. Concentrations of organohalogen compounds in water and sediment were in the range of ND (nondetectable)–1.16 ng/L (average ± standard deviation: 0.342 ± 0.308 ng/L) and ND–0.30 ng/g (0.063 ± 0.093 ng/g) for HCHs (α-, β-, and γ-HCHs), 1.66–15.8 ng/L (6.36 ± 3.23 ng/L) and ND–6.85 ng/g (1.99 ng/g ± 1.04 ng/g) for endosulfans (α- and β-endosulfan, and endosufan sulfate), 0.019 ng/L–0.216 ng/L (0.097 ± 0.060 ng/L) and 0.091–12.13 ng/g (3.11 ± 4.21 ng/g) for 17 PBDEs, and ND–69.02 ng/L (14.06 ± 19.44 ng/L) and ND–3.715 ng/g (0.68 ± 1.16 ng/g) for PFCs (PFOA and PFOS), respectively. Different distribution of these POPs was observed between water and sediment even in the same locations, which might be due to the characteristics of continuously changing river water and stationary sediment as well as the different physicochemical properties of the POPs.