Trend of POPs Contamination in the Marine Environments of South Korea

Abstract

Usage of legacy POPs such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) have been under restriction or banned in South Korea since 1969-1982. However, regular monitoring of persistent organic pollutants (POPs) in the marine environments has begun only in the mid 1990s. These compounds have been detected ubiquitously in both offshore and coastal sediments and biota in Korean waters. The concentration levels were several orders of magnitude lower than those found in the developed countries. There was no clear sign of decreasing trend in the period of mid 1990s to the early 2000 in the coast of Korea. However, continuous monitoring of legacy POPs including polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs) in Masan and Gwangyang bays has revealed a decreasing trend in concentrations in sediments from the mid 1990s or the early 2000 to 2010. Polycyclic aromatic hydrocarbons (PAHs) and nonylphenol (NP) concentrations also decreased during that period in Masan Bay, one of most polluted and well monitored bays in South Korea. Decreasing trend of those legacy POPs and other organic pollutants were supported with the age dated sediment core analyses. In contrast, DDTs levels in the age dated sediment core in the central part of the Yellow Sea, however, demonstrated increasing trend in the last several decades. It might be due to relocation of old DDTs