| The enhanced release of anthropogenic contaminants in to the environment can be regarded as the unavoidable cost of economic development, but care should be taken that the adverse effects of these compounds are properly balanced against the desirable effects of economic growth and development. To this end, knowledge of contaminant sources, transport pathways, and the interaction of these two with economic development, is indispensable for environmental managers and policy makers, in particular because the pollution of coastal areas can take place quickly (hours to years), but the removal of many contaminants from the environment is a slow process (decennia to centuries). The sources of contaminants determine if and how remedial measures to reduce pollution levels in coastal areas can be taken. Local sources (e.g., agriculture, industry, mining, shipping) are amenable to regional and national control, but non-localised sources (e.g., long-range atmospheric inputs) require action on the international level. Following their release in to the environment, contaminants are subject to a number of transformation and transport pathways, such as transport via the dissolved phase and via particles, either in air or in water. Evaporation likely is an important escape route of semi-volatile organic contaminants in tropical areas, but little is known about the magnitude of losses via this pathway. A complex relation likely exists between contamination levels in the coastal zone and socio-economical factors. With ongoing development of the area, the relative and absolute magnitude of the various contamination sources is expected to change as a result of increases in food demand, industrialisation, automotive transport, and shipping. Increased emissions do not necessarily result in increased exposure concentrations when elimination transport pathways become more efficient (e.g., enhanced erosion may results in an increase in the fraction of bound contaminants, and decreased rainfall may enhance the importance of the evaporation pathway). We propose to carry out a contaminant fate study in the Berau area, focussing on the compartments water, air, sediment, biota, and particulate phase, and targeting the contaminants of primary concern. We seek to identify the sources of these compounds and their most important transport pathways. We aim to understand the present distribution of contaminants, as well as their historical record (as inferred from the analysis of dated sediment cores), in relation to the socio-economic development of the area. Finally, we wish to develop a tool that helps environmental managers to predict the evolution of contaminant stresses. |
