Permeation of Chlorpyrifos and Endosulfan Formulations Through Gloves

Abstract

The aim of this study was to determine the safe wearing periods for lined nitrile, Silver Shield laminate, and Viton gloves for challenges by the pesticide emulsifiable concentrates Lorsban 4E (chlorpyrifos active ingredient) and Thiodan 3 E.C. (endosulfan). An American Society for Testing Material-type permeation cell was used with hexane collection solvent at 30°C. Subsequent gas chromatography/mass spectrometry of collection side samples was done for samples taken every 10 minutes. For nitrile, endosulfan took 2 hours to break through, whereas chlorpyrifos took 2.5 hours, with the alkylbenzene inert components permeating after 20 minutes. The pesticides began permeating during the steady-state permeation periods of the inert components. This suggested an inert component facilitated transport mechanism for the pesticide with differential breakthrough. Both pesticides showed two steady-state periods in their cumulative mass versus time permeation curves. The second steady-state permeation rate was five to seven times the rate of the first, the average rates for the latter being 580 ± 250, 809 ± 70, and 430 ± 35 ng/cm²/min, respectively, for chlorpyrifos, α-endosulfan, and β-endosulfan. Silver Shield and Viton gloves did not allow pesticide or inert component permeation over 480 minutes, and are thus recommended for hand protection over nitrile.