Air to lung partition coefficients for volatile organic compounds and blood to lung partition coefficients for volatile organic compounds and drugs

Values of in vitro gas to lung partition coefficients, Klung, of VOCs have been collected from the literature. For 44 VOCs, application of the Abraham solvation equation to log Klung yielded a correlation with R2 = 0.968 and S.D. = 0.25 log units. Combination of the log Klung values with log Kblood values leads to in vitro blood to lung partition coefficients, log Plung for 43 VOCs; an Abraham solvation equation correlated these values with a very poor R2 = 0.262 but with a very good S.D. = 0.190 log units.Values of in vivo log Plung for 80 drugs were collected, and were correlated with R2 = 0.647 and S.D. = 0.51 log units. When the log Plung values for VOCs and drugs were combined, an Abraham solvation equation could correlate the 123 compounds with R2 = 0.676 and S.D. = 0.43 log units. Division of the 123 compounds into a training set and a test set, showed that the training equation could predict log Plung values with an average error of 0.001 and a standard deviation of 0.44 log units; for drugs in the combined test set the average error was 0.02 and the standard deviation 0.43 log units.

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