摘要：In this review a discussion on some factors inuencing the exposure matrices which, in turn, inuences the reliability of ecotoxicological bioassays on aquatic sediments, has been carried out. These factors include the variability induced on sediments by the sampling, storage, handling, and preparative operations. The exposure matrices-sediments in toto, interstitial water and elutriate, can be deeply modied by these actions, which alter the chemicals bioavailability and, therefore, the bioassay meaning. In order to obtain reproducible and scientically valid data, to be used in the ecological risk assessment, all these factors need to be considered and kept under control.
