Influence of laboratory storage on the organic contaminant content and water-extractable ecotoxicological potential of soil samples.

At present there is a high level of uncertainty about whether or not soil samples, which are required to be toxicologically characterized, could be preserved without affecting their toxicological characteristics. In the existing DIN/ISO standards for soil investigations, there is no documentation on the storage of soil samples after collection for (eco-)toxicological investigations. Furthermore, procedures for receiving justifiable and verifiable results from soil samples are quite vague. Therefore, the stability and changes in the biological effects of different soil contaminants were investigated by varying the storage conditions and the storage times of the soil. The limitations of storing soils could therefore be subsequently outlined. Recommendations for the optimization of storage conditions for back-up soil samples were made. These recommendations have the capability of finding entrance into DIN/ISO standards.