Development of QSAR's in soil ecotoxicology: Earthworm toxicity and soil sorption of chlorophenols, chlorobenzenes and chloroanilines

Abstract

Soil adsorption and the toxicity of four chloroanilines for earthworms were investigated in two soil types. The toxicity tests were carried out with two earthworm species, Eisenia andrei and Lumbricus rubellus. LC50 values in mg kg−1 dry soil were recalculated towards molar concentrations in pore water using data from soil adsorption experiments. An attempt has been made to develop Quantitative Structure Activity Relationships (QSAR's) using these results and data on five chlorophenols and dichloroaniline in four soils and five chlorobenzenes in two soils published previously (Van Gestel and Ma, 1988, 1990; Van Gestel et al., 1991). Significant QSAR relationships were obtained between 1) adsorption coefficients (log K om ) and the octanol/water partition coefficient (log k ow ), and 2) LC50 values (in itμmol L−1 soil pore water) and log K ow . It can be concluded that both earthworm species tested are equally sensitive to chlorobenzenes and chloroanilines, E. andrei is more sensitive than L. rubellus to chlorophenols.