Chemical toxicity correlations for several protozoas, bacteria, and water fleas based on the Abraham solvation parameter model

Chemical toxicity data for three species of water fleas (Daphnia magna, Ceriodaphnia dubia, and Daphnia pulex), two protozoas (Tetrahymena pyriformis and Spirostomum ambiguum), and one bacterium (Pseudomonas putida) were retrieved from the published chemical literature. The compiled data were correlated with the Abraham solvation parameter model. Derived mathematical correlations described the observed published toxicity data to within an overall average standard deviation of approximately 0.27 log units. Principal component analysis of the correlation equations showed that the water–octanol system is a poor model for nonspecific aquatic toxicity, but that the water–isobutanol and water–pentanol systems are much better models.Key words: aquatic toxicities, median lethal molar concentration, polar narcosis, nonpolar narcosis, mathematical correlation, solvation parameter model, principal component analysis.