Multiresidue Analysis of Pesticides in Wines Using C-18 Solid-Phase Extraction and Gas Chromatography-Mass Spectrometry

¹ Bureau of Alcohol, Tobacco and Firearms, Alcohol and Tobacco Laboratory, National Laboratory Center, 1401 Research Blvd., Rockville, MD 20850.

jwwong{at}atfhq.atf.treas.gov

Procedures to analyze pesticides in wines were developed and evaluated. Wine samples were applied to solid-phase extraction cartridges (C-18, octadecyl), and pesticides were eluted with ethyl acetate. The reduced solvent extracts were subsequently screened and analyzed by gas chromatography-mass spectrometry using full scan or selected ion monitoring. Target and qualifier ions and retention times were used to screen, confirm, and determine recoveries of 48 common pesticides. Various parameters including pesticide spike concentrations, wine type (red and white), and salt addition prior to extraction were compared and evaluated for highest extraction efficiencies and optimal sensitivity in spiked wine samples. Suitable recoveries to most pesticides at the 0.01 and 0.10 mg/L fortifications were obtained by adding sodium chloride prior to extraction and ethyl acetate elution. These findings confirm that this is a fast and effective method for identifying several types of pesticides in wines.

Key words: pesticides in wine, identification, GC/MS

Submitted on March 23, 1999
Revised on August 10, 1999