Formulas for calculation of extraction volumes for commonly used pesticide residue extraction procedures

Formulas are presented for the calculation of extraction volume for pesticide residue procedures that use a single extraction with acetone, acetonitrile, or methanol, with or without prior dilution of these solvents with water. These formulas account for the volume change on mixing and for the volume contribution from the soluble sugars sucrose, glucose, and fructose. Results using these formulas are in agreement with the observed volumes of such mixtures within 0.3% throughout the following ranges, expressed as percent water in the mixtures: 15-38% for acetone, 4.8-59% for acetonitrile, and 9.3-33% for methanol.