Dietary risk assessment of organophosphorus and dithiocarbamate pesticides in a total diet study at a Brazilian university restaurant

Abstract

In this study ready-to-eat food samples were collected in the production line of the university restaurant of the University of Brasilia, Brazil, which serves non-vegetarian and vegetarian meals daily. Samples were analysed for the presence of ten organophosphorus insecticides (OPs) by GC/FPD, after extraction with ethyl acetate and anhydrous sodium sulfate (LOQ = 0.002 mg kg^–1), and for dithiocarbamate fungicides, as CS₂, using the spectrophotometric method (LOQ = 0.05 mg kg⁻¹). About 43% of the 175 samples analysed contained at least one OP compound at levels up to 1.83 mg kg⁻¹. Methamidophos was the compound most detected (37.7%), present in most of the soup, soybean and salad samples. No OP residues were found in fruit juice, beans and bran rice samples. The cumulative acute intake of OPs was estimated using methamidophos and acephate as index compounds (IC). The total cumulative intake represented 9.1% and 47.7% of the methamidophos ARfD for the non-vegetarian and vegetarian diets, respectively. When acephate was used as IC, the total intakes represented 20.7% and 116% of the ARfD for the non-vegetarian and vegetarian diets, respectively. Dithiocarbamates were detected in 70% of the 177 samples analysed, at levels up to 0.51 mg kg⁻¹ CS₂; all salad samples were positive and no residues were found in fruit juice. The chronic intake of dithiocarbamates represented 8.6 and 8.9% of the ADI (mancozeb) for the vegetarian and non vegetarian diets, respectively.

Keywords:

• gas chromatography
• exposure assessment
• risk assessment
• total diet
• pesticide residues
• organophosphorous
• vegetables
• fruit
• animal products
• meat
• beans