Some methods of obtaining quantitative structure-activity relationships for quantities of environmental interest

Methods are described for obtaining quantitative structure-activity relationships (QSAR) for the estimation of quantities of environmental interest. Toxicities of alkylamines and of alkyl alkanoates are well correlated by the alkyl bioactivity branching equation (ABB). Narcotic activities of 1,1-disubstituted ethylenes are correlated by the intermolecular forces bioactivity (IMF) equation. When the data set has a limited number of substituents in equivalent positions the group number (GN) equation, derivable from the IMF equation, can be used for correlation. It has been successfully applied to aqueous solubilities, 1-octanol-water partition coefficients, and bioaccumulation factors and ecological magnifications for organochlorine compounds. A combination of the omega method for combining data sets for different organisms with the GN equation has been used to correlate toxicities of organochlorine insecticides in two species of fish. Toxicities of carbamates have been correlated by a combination of the zeta method and the IMFB equation. The ABB and the GN equations are particularly useful in that they generally do not require parameter tables, and that the parameters they use are error-free. The methods presented here, as shown by the examples given, should make it possible to establish a collection of QSAR for toxicities, bioaccumulation factors, aqueous solubilities, partition coefficients, and other properties of sets of compounds of environmental interest.