Project rheingold: Rapid biosensor analysis of soil and groundwater toxicity

A toxicity survey can provide invaluable information prior to managed bioremediation of industrially contaminated sites. Furthermore, toxicity monitoring is often required during site remediation to monitor progress. Conventional toxicity assessment involves analytical techniques such as spectrometry, chromatography (HPLC and GC), CC-mass spectrometry and atomic absorption techniques for the determination of heavy metals. These techniques are powerful and sensitive to ppm and ppb levels. However, the ability to detect a compound does not provide information regarding the biological effects of that compound, its persistence in the environment, or information that can be employed in the design of a remediation strategy, lux-marked bacterial biosensors have been found to be rapid and sensitive indicators of toxicity of a wide range of organic and inorganic pollutants. This paper reports the use of lux-marked Escherichia coli (selected as a general indicator) and lux-marked pseudomonads (selected for site relevance) to assess the toxicity of soils and groundwater at a BTEX contaminated site. This approach, coupled with a regime of sample manipulation, allows the determination of the nature of the toxicity as well as providing information on which to base a remediation strategy.