There is an increasing need for appropriate methods to determine soil quality and the effects of xenobiotics on soil organisms (Tarradellas and Bitton, 1997). The first and most standard methods for risk assessment of chemicals on soil organisms are the use of laboratory toxicity tests. These tests are used to estimate critical threshold concentrations from concentration-response relationships for single life cycle variables such as survival, growth and reproduction.
The development of more sensitive and predictive test methods to characterize the risk associated with exposure to xenobiotics is an area of intense research. One of these approaches is based on the use of biomarkers. By combining this approach with toxicity tests, as done in the present study, it is possible to determine if biomarkers are more sensitive or predictive in detecting the effect of pollutants. The results will represent a step towards a better extrapolation from the cell to the population and from acute to chronic toxicity.