Tracking pesticide exposure to operating workers for risk assessment in seed coating with tebuconazole and carbofuran.

Background: Coating seed with pesticides is an effective way to control plant pests, however, factory-based coating processes may carry a potential risk to operational workers of chemical exposure. To study the risk, carbofuran and tebuconazole were used to coat corn seed and their subsequent distribution on the bodies of workers was measured at manufacturers XFS and LS (Shanxi, China). Clothing was collected from workers during operations and analyzed using high-performance liquid chromatography.

Results: At XFS, dermal exposure to carbofuran was 4.83, 3.31 and 1.48 mg kg , and exposure to tebuconazole was 6.88, 5.16 and 1.72 mg kg for coating, packing and transport workers, respectively. At LS, dermal exposure to carbofuran was 2.32, 0.46 and 0.55 mg kg , and exposure to tebuconazole was 1.69, 0.46 and 0.70 mg kg , for coating, packing and transport workers, respectively. The level of pesticide exposure was significantly higher for seed-coating workers than for packing and transport workers. The main area of exposure was the hands for all workers and the lower limbs for packers; exposure was relatively uniform for pesticide handlers. Occupational risk was assessed based on margin of exposure (MOE). In seed-coating, the MOE was greater than 100 for tebuconazole, indicating no potential risk, but ranged from 0.25 to 2.88 for carbofuran, indicating the risk of a health impact.

Conclusion: The level of exposure varied depending on type of operation undertaken and body parts of workers' body, but the risk of a health impact was highly associated with pesticide toxicity. This provides a guideline for workers in pesticide manufacturing to ensure safe operation of the seed-coating process. © 2021 Society of Chemical Industry.