Organic chemical pollutants and bio-assays : matrimony between chemistry and biology / Rialet Pieters

Abstract

Knowing the concentration of a pollutant in the environment, i.e. sediment, soil, water, and air, and comparing it to a guideline level to know whether it occurs at an ‘acceptable’ level, is not adequate anymore. Biota in the environment is exposed to a mixture of compounds, and even if the exposure does not lead to acute toxicity and immediate death of the organism, the combined effects of continuous exposure to low concentrations of many xenobiotics over a lifetime, may lead to detrimental health effects of both humans and other living organisms. Biota living in a polluted environment may present evidence of how the toxicants in their environment have harmed them, but by the time the effect of pollution is visible on organismal and population level, mitigation might be too late. This is where the application of in vitro bioassays become useful. Extracts from environmental matrices may be administered to tissue cultures to determine harmful effects timely. In my research, bio-assays are employed to specifically determine endocrine disruptive effects. These reporter gene-bioassays are semi-quantitative and although the precise identity of the pollutants are not known, the biological effect of the total mixture of pollutants are known. Based on the results from bio-assays, useful predictions and extrapolations can be drawn to improve management and protection of biota and human life.