Performance of the ALOGPS 2.1 program for octanol-water partition coefficient prediction with organic chemicals on the Canadian Domestic Substances List

Sierra Rayne,Kaya Forest

doi:10.1038/npre.2009.3882.1

Abstract

AbstractThe KOWWIN and ALOGPS octanol-water partition coefficient (K~ow~) estimation software programs were compared for their capacity to accurately predict log K~ow~ values of 1596 organic compounds on the publicly available Domestic Substances List (DSL) from Environment Canada for which experimental data is available. KOWWIN contained a significantly lower number and magnitude of prediction errors compared to ALOGPS, particularly at experimental log K~ow~ values <2. Substantial predictive differences were observed between the two programs for 9093 compounds not having experimental K~ow~ data on the Canadian DSL. Predictive differences of up to 40 log K~ow~ units were found between KOWWIN and ALOGPS, and in some cases, the discrepancies were sufficiently large that strongly opposing hydrophobicity classifications were obtained.

Highlights

Octanol-water partition coefficients (Kow) are widely used in environmental and biological chemistry to predict and understand the partitioning behavior of neutral organic compounds and their salts into a range of organic materials
From an initial sample of 1771 experimental log Kow values in the Canadian Domestic Substances List (DSL) listing, the removal of some duplicate entries and errors resulted in a reduced set of 1596 compounds (Appendix Table 1)
The substantial number of errors and omissions in the original source Canadian DSL experimental Kow list necessitates prescreening by researchers prior to use

Summary

Introduction

Octanol-water partition coefficients (Kow) are widely used in environmental and biological chemistry to predict and understand the partitioning behavior of neutral organic compounds and their salts into a range of organic materials. =N(Cl)(C)C)c3ccccc3 cyclohexadien-1-ylidene]-N-methyl-, chloride pentanedioic acid, dimethyl ester 0.84 0.67 -0.17 propanoic acid, methyl ester 0.94 1.04 0.10 acetic acid, chloro-, ethyl ester 1.21 1.36 0.15 propanoic acid, ethyl ester

Results

Conclusion