Determination of organochlorine pesticide residues in honey from the central zone of Portugal and the Valencian community of Spain

Abstract

In this study nine organochlorine pesticide residues (α-, β-, and γ-hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), aldrin, p, p′-DDE, p, p′-DDD, o, p′-DDT, and p, p′-DDT) in forty nine samples of honey collected from markets of Portugal and Spain during 2001 and 2002, respectively, were evaluated. For this evaluation, three analytical procedures were studied. The analytical procedure, based on LLE extraction with ethyl acetate followed by gas chromatography–electron-capture detection (GC–ECD) for quantification, and mass spectrometry (GC–MS) for confirmation, has been selected. Recoveries of spiked samples ranged from 68%, for β-HCH, and 126% for p, p′-DDT, for fortification levels between 10 and 100 μg/kg, and 64%, for α-HCH, and 143% for γ-HCH for fortification levels between 20 and 200 μg/kg. Limits of quantification, using GC–ECD, were from 0.01 and 0.10 mg/kg, and limits of detection between 0.001 and 0.02 mg/kg. Fourteen Valencian samples were contaminated, containing residues of HCB or/and HCH isomers. The frequency of detection was 56% for Spanish samples. In Portugal, 23 samples were contaminated, what means 95.8%. In Spanish samples, concentrations range from nd to 0.03 mg/kg for HCB, and nd to 2.24 mg/kg for HCH-total. The mean concentration and standard deviation were 0.017 ± 0.011 mg/kg for HCB, and 0.579 ± 0.747 mg/kg for HCH-total, contributing the γ isomer with the highest values. The samples from Portugal showed higher levels. Levels of HCB ranged from nd to 0.39 mg/kg. HCH-total ranged from nd to 4.86 mg/kg, and DDT-total from nd to 0.658 mg/kg. Mean concentration and standard deviation were 0.09 ± 0.116 mg/kg for HCB, 1.357 ± 1.30 mg/kg for HCH-total, and 0.143 ± 0.193 mg/kg for DDT-total.