Research Product

Predictive toxicological models, including estimates of uncertainty, are necessary to address probability-based ecological risk assessments. A method and software (ICE) were developed for estimating acute toxicity of chemicals to species, genera, and families when data are lacking. Interspecies correlation models for acute toxicity (4082 models) were derived for 143 aquatic and terrestrial organisms using Model II least squares regression, where both variables are independent and subject to measurement error (log X2=a+b[log X1). Toxicity of a chemical to one species can be predicted from toxicity to another species with known certainty. Correlations are generally best within a taxonomic family, decreasing with increasing taxonomic distance. However, certain species (e.g., rainbow trout) were found to be the most useful of all species for acute estimations among taxa, including families. Correlations for wildlife species were not as good, in general, as those for aquatic species, but routes of exposure are different -- oral or dietary versus respiratory, respectively.