A new quality assurance system for the evaluation of ecotoxicity studies submitted under the New Substances Notification Regulations in Canada.

New substances destined for import into, or manufacture in, Canada must be reported to Environment Canada and Health Canada under the New Substances Notification Regulations (Chemicals and Polymers) (NSNR). With the use of information provided by the notifier, and other complementary information available to the 2 departments, the New Substances Program conducts ecological and human health risk assessments. Over the past 10 y, more than 750 ecotoxicity studies have been submitted to the New Substances Program of Environment Canada under the NSNR. Most of these experimental studies are not publicly available but are useful in the ecological risk assessment of new substances and for the development of Quantitative Structure-Activity Relationships (QSARs). In this paper, we describe the development and validation of a computer-based scoring system and our approach in the development of scoring methods used to assess the quality and usability of ecotoxicity studies with fish, Daphnia spp., and green algae. Results of ranking exercises conducted with these methods are described and discussed, together with the potential use of these results in a regulatory context. In addition, the methods are discussed in comparison with other similar evaluation schemes described in the literature.