Integrated assessment of trace pollutants associated with the Korean coastal environment: Exampled from the sediment TIE and triad approaches

Here we present our triad approach followed by major findings based on sediment pollution studies that determined the chemical concentration, biological effect, and community structure associated with trace pollutants in the Korean coastal environment. Since the late-1990s, over several hundred sites along the Korean coast have been surveyed including sediment (including pore-water), water, and biological samples and analyzed for instrumental quantification, in vitro and in vivo bioassays, and benthic community indices. The instrumental data of persistent heavy metals and organic pollutants in Korean sediments generally suggest that concentrations of target pollutants are relatively low to moderate but their distribution is widespread across the coasts. The compositional pattern and spatial distribution suggests that their sources are independent of each other. However, there are local zones with extremely high concentrations of certain pollutants indicating point sources. In order to search for the relationship between chemical concentrations and biological responses, some selected data (n=123) were further analyzed in terms of mass balance analysis (sediment-TIE towards TEQ approach). Most of the dioxin-like activities were observed in the fractions containing dioxins, furans, and certain polycyclic aromatic hydrocarbons (PAHs) and about half of the samples showed significant estrogenic activities in the fractions of PAHs and alkylphenols. Direct relationship(s) between chemical and ecotoxicological data could not be fully addressed between component(s). However, a positive relationship between them became apparent in some cases, indicating a general good agreement between chemical stresses and biological responses. Overall, we found that a sediment triad approach for an integrated assessment of trace pollutants in the coastal environment was extremely useful. It would be much more powerful when all the components are fully and simultaneously analyzed and interpreted.