Methods for Monitoring and Assessment of Bioremediation Processes

Abstract

The cleanup of the contaminated soils is a priority environmental task due to the risks contaminants pose to the groundwater, drinking water and soil fertility. A wide variety of biological, physical and chemical methods have been developed to decontaminate polluted sites. Any successful remediation technology should not simply transfer the contaminants to other environmental compartments. Bioremediation provides a cost-effective and contaminant/substrate-specific treatment technology (Ward et al. 2003). A successful bioremediation approach requires sufficient proof for the detoxification of the contaminants, preferably proven by complete mineralization (Dua et al. 2002). However, the determination of effectiveness and completeness to satisfactory status is one of the major problems. Current monitoring practices require the determination of the disappearance of the contaminants and their degradation products to regulatory levels are monitored followed by toxicity testing, usually on a single organism or species to make sure that there is no product or induced change resulting in any residual toxicity. The problems related to these monitoring approaches and to the assessment of successful bioremediation have been widely recognized and discussed (Höhner et al. 1998; White et al. 1998; van Straalen 2002; Widada et al. 2002a). The microbial community response may prove to be a much more comprehensive indicator of residual toxicity, which is more sensitive than single species toxicity screens, and can be used to complement the disappearance or sequestration of contaminants.