Investigation of correlations between chemical parameters of metal ions and acute toxicity in mice and Drosophila.

We are studying correlations between physicochemical properties associated with metal ions and observed toxicity. In order to test correlations, we obtained, under uniform conditions, LD50 values for acute toxicity in mice for 24 metal ions. The new data show a better correlation between LD50 and Pearson and Mawby's softness parameter sigma p, defined using chemical concepts of hard and soft acids and bases, than had been obtained by others. From a wide range of physicochemical parameters, the electrode potential can give almost as good a correlation as sigma p. Better correlations might exist for parameters more relevant to biological systems.