Monitoring of pesticide residues in domestic vegetables in Thailand during 2015

Abstract

In Thailand, the Ministry of Public Health has the responsibility for regulatory monitoring safety of food. To assess the residue levels and to evaluate the exposure of the Thai population to pesticides, a nationwide surveillance program for pesticide residues in vegetables has been performed during 2015. A total of 934 samples of four types of vegetables including Chinese broccoli, ivy gourd, yardlong bean and water spinach were collected from wholesale markets by 77 Provincials Public Health Offices in collaboration with 14 Regional Medical Sciences Centers. All samples were sent to the accredited laboratory of the Bureau of Quality and Safety of Food and were examined for residues of 60 pesticides, including 20 organochlorines, 23 organophosphorus, 8 synthetic pyrethroids, 7 carbamates and 2 fungicides using multi-residue extraction and chromatography method. Predominantly, 22.3% of the samples had detectable pesticide residues at levels ranging from <0.01 to 5.9 mg/kg. Of the contaminated samples, the levels of 33.9, 31.9, 10.6 and 9.5% of the samples were pesticides detectable in yardlong bean, Chinese broccoli, ivy gourd and water spinach, respectively. The results showed a potential human dietary risk related to consumption of these vegetables. Governmental action plans should be developed with the cooperation of producers to reduce pesticide residues.