Influence of the presence of ethanol on in vitro bioavailability of fungicide residues

Abstract The influence of ethanol on the in vitro bioavailability of nine fungicides in wines of varying degrees of alcohol is studied by simulating the digestive process by dialysis in semipermeable membranes. The dose of each fungicide corresponds to its added Maximum Residue Limits in the different matrices (water, ethanol, wines of 7, 11, 13 and 14.5% ethanol). A validated analytical methodology was used which includes extraction, partition according to the modified QuEChERS multiresidue method and liquid chromatography with triple quadrupole tandem mass spectrometry analysis. Interaction between the ethanol content and bioavailability was confirmed and increases were found in the dialyzed percentages with respect to the blank (the standard in water) for ametoctradin, mepanipyrim, cyazofamid, pyraclostrobin and metrafenone, while a decrease was observed for dimethomorph, boscalid and kresoxim-methyl. Fenhexamid showed no significant differences by alcohol content.