Dermal exposure and health risk assessment of emamectin benzoate among Thai farmers in Phitsanulok

Abstract

Emamectin benzoate (EB1) is a widely used pesticide in Thailand for controlling pests in rice and corn production. This study aimed to assess dermal exposure to EB1 among farmers using patch sampling and to evaluate the associated health risks. Seventy farmers regularly apply EB1 on their farms participated in this study. Seven patch samplers were attached to each participant at different body locations (head, chest, abdomen, upper arm, upper leg, lower leg, and back) to detect EB1 residues. The pesticide levels in the patches were analyzed using high-performance liquid chromatography with ultraviolet detection (HPLC-UV), and dermal risk assessment was performed using the hazard quotient (HQ) method. EB1 was detected on clothing in 5 participants (7.1 %) during the rice and corn planting seasons. The mean ± SD EB1 concentrations were 4.80 ± 1.06 mg/kg (range: 3.87–6.41 mg/kg) during rice planting and 4.13 ± 3.30 mg/kg (range: 1.24–8.91 mg/kg) during corn planting. All skin patch samples were below the limit of quantification (LOQ = 1.00 mg/kg) and limit of detection (LOD = 0.3 mg/kg). The calculated HQ values were all ≤1, indicating acceptable risk levels. These findings suggest minimal dermal exposure, likely due to effective protective clothing and application practices. Nonetheless, further improvements in personal protective equipment (PPE) and routine monitoring are recommended to reduce potential long-term health risks.