Multiresidue determination of 19 fungicides in processed fruits and vegetables by capillary gas chromatography after gel permeation chromatography

A gas chromatographic (GC) method was developed for simultaneous determinat ion of 10 fungicides (chlorothalonil, vinclozolin, dichlofuanid, triadimefo n, penconazole, chlozolinate, captan, procymidone, triadimenol, folpet, hex aconazole, myclobutanil, cyproconazole, propiconazole, nuarimol, captafol, iprodione, fenarimol, and bitertanol) and the acaricide tetradifon in tomat o puree, peach nectar, orange juice, and canned peas. Samples were extracte d with acetone, partitioned with ethyl acetate-cyclohexane (50 + 50, v/v), and cleaned using gel permeation chromatography with ethyl acetate-cyclohex ane (50 + 50, v/v) as eluant. The final extract was analyzed by GC with ion trap mass spectrometry (ITMS) using a DB5 capillary column. Recoveries fro m fortified samples ranged from 74.6 to 99.3%, except for triadimenol and b itertanol. Quantitation limits for most anlytes were between 0.005 and 0.05 0 mg/kg. The purified extracts were analyzed further by GC with electron ca pture and nitrogen phosphorus detection, and the results were compared with those obtained by ITMS.