Exposure Assessment for Some Pesticides through Rice Consumption in Iran Using a Multiresidue Analysis by GC-MS

In communities which consume rice as main food, importance of risk assessment for contaminants is always taken into consideration by health authorities. The present study is an attempt for monitoring of 56 pesticides from different chemical groups in rice samples collected from local markets in Tehran and estimation of daily intake of interested pesticides through this monitoring. A valid method based on spiked calibration curves and QuEChERS sample preparation was developed for determination of pesticides residue in rice by GC/MS. The analytical results of the proposed method were in good agreement with the proficiency test (FAPAS 0969). One-hundred-thirty-five rice samples were analyzed and 11 pesticide residues were found in 10.4% of the samples. Of which 5.2% were contaminated with unregulated pesticides. None of the samples, which were contaminated with regulated pesticides, had contamination higher than maximum residue limit. The mean estimated dose (ED) was calculated with respect of mean of contamination and mean daily consumption of rice. ED of the found pesticides is much lower than the related ADIs.