Determination of Organic Contaminants in Sediments Using Trace Analysis and Biological Screening Assay

Abstract

Gwangyang Bay located in the southern coast of Korea is a semi-enclosed embayment including a big steel mill plant and petroleum refinery plant complex around the bay. Several biomarkers and bioassays were accompanying with chemical analysis to monitor extent of contamination and effects of organic pollutants for the basic study to prepare a national action plan for protection of the marine environment from the land-based organic pollutants. Organic pollutants (PCBs, PAHs, organochlorine pesticides, organotins, alkylphenols, and phthalate esters) were analyzed in the surface sediment from the bay. In addition, bioassays, including four cytotoxicity tests (cell viability, esterase activity, double strand DNA content and cell membrane micro-viscosity) and E-screen assay with yeast transformants, were applied to sediment extract to evaluate toxicity and estrogenicity of sediments. Enzyme activity (EROD, MROD and GST) of feral fish collected from the polluted site of the bay and a reference site was measured as exposure biomarker for organic pollutants. Imposex in marine snail, were also applied to assess specific effect of organotin, especially tributyltin in the bay.Although the causality of effects on marine organisms were not clearly revealed in all the field studies, the measurable amount of certain effects in several bioassays indicate that organic toxicants in the coastal environment of Korea probably cause adverse effects on the marine organisms. However, more finely designed toxicity identification and evaluation (TIE) approach is required to confirm major stressors and to manage marine pollutions in the study area.