Detection of Organophosphate and Carbamate Pesticide Residues in Fresh Vegetables in Phra Nakhon Si Ayutthaya Province and Effectiveness of Washing Methods on Pesticide Residues in Kale

Abstract

The aim of the project is to study residues in organophosphate and carbamate pesticides in vegetables grown and sold in Phra Nakhon Si Ayutthaya province, and to study the effect of washing methods on pesticide residues in selected vegetable. A total of 150 samples, which were collected from the crop (65 samples) and from the distribution points (85 samples) in the province, of 21 vegetable types was tested with a Test Kit MJPK to detect the residues of organophosphate and carbamate insecticides. From the total of 150 vegetable samples, the detection of chemical residues was in a safe grade of 81 samples (54% of total samples), which referred to 45 and 36 samples of vegetables grown and sold in the province, respectively. There were 69 samples of unsafe grade (46% of total samples), which referred to 20 and 49 vegetables grown and sold in this area, respectively. The pesticide residues in climbing wattle, salad, bitter cucumber and mushroom were marked as safe (100% of each vegetable types), but the contaminated vegetables found in high proportions were lemon grass, Phak-Wan, and coriander (80, 80 and 71%, respectively). In addition, the washing vegetable with sodium bicarbonate and potassium permanganate could eliminate pesticide residues in kale.