A review of quantitative structure-activity relationship methods for the prediction of atmospheric oxidation of organic chemicals.

Organic compounds are chemically transformed in the troposphere by reaction with photochemically generated oxidants that include hydroxyl radicals, nitrate radicals, and ozone. The reaction rates are a measure of atmospheric persistence and are necessary for developing environmental exposure assessments. Since relatively few experimentally measured rate constants are available, environmental risk/exposure assessors must estimate degradation rates. Rates can be predicted through use of quantitative structure-activity relationships (QSARs). QSAR methods are described for estimating reaction rates with hydroxyl radicals, nitrate radicals, and ozone. QSAR accuracy and limitations are also discussed.