Silicone wristband as a sampling tool for insecticide exposure assessment of vegetable farmers

The use of passive sampling devices (PSDs) as an appropriate alternative to conventional methods of assessing human exposure to environmental toxicants was studied. One-time purposive sampling by a silicone wristband was used to measure insecticide residues in 35 volunteer pepper farmers in the Vea irrigation scheme in the Guinea savannah and the Weija irrigation scheme in the coastal savannah ecological zones of Ghana. A GC-MS/ MS method was developed and validated for quantifying 18 insecticides used by farmers in Ghana. Limits of detection (LODs) and quantitation (LOQs) ranged from 0.64 to 67 and 2.2-222 ng per wristband, respectively. The selected insecticides showed a range of concentrations in the various silicone wristbands from not detected to 27 mu g/wristband. The concentrations of 13 insecticides were above their LOQs. Chlorpyrifos had the highest detection frequencies and concentrations, followed by cyhalothrin and then allethrin. This study shows that silicone wristbands can be used to detect individual insecticide exposures, providing a valuable tool for future exposure studies. Ghanaian vegetable farmers are substantially exposed to insecticides. Hence, the use of appropriate personal protective equipment is recommended.