Determination of occupational risk and exposure to pesticide residues on vegetables among greengrocers in fresh market Bangkok Thailand

Abstract

This mixed methods study aimed at assessing the magnitude of health risk from occupational exposure to pesticide residues (PRs) on vegetables. The study was conducted among 91 greengrocers in Padung Krung Kasem market, Bangkok. Data was collected in dry (April-May) and wet (August-October) seasons, including face-to-face interview, hand wipe sampling, and blood cholinesterase (ChE) level test, and then in-depth interview was conducted. The study revealed that all hand wipe samples contained many kinds of insecticides, including organophosphates, carbamates, and pyrethroids. PRs on hands detected in all samples were chlorpyrifos and cypermethrin. Wilcoxon signed rank test revealed that amount of chlorpyrifos and types of PRs on hands in the wet season significantly decreased when compared to the dry season (p<0.05), while amount of cypermethrin did not significantly differ. In addition, there were statistically significant differences in blood ChE level in both seasons (p<0.001). The most reported symptoms from exposure to PRs were fatigue/tiredness, skin rash/itching, headache, and eye irritation/blurred vision. At 99th percentile values of PR exposure, average daily dose (ADD) was 2.42x10-5 mg/kg/day and hazard index did not exceed acceptable level (HI=0.287). Besides, the significant relationship among practice regarding PR exposure, PRs on hands, ChE level, and health symptoms were found (p<0.05). Occupational exposure to PRs with poor practice may pose health effects. These findings suggest that risk communication among greengrocers should be done with guideline related to pesticide contamination in vegetables, especially proper personal hygiene practice, to prevent them from PR exposure and potential health risks.