Folpet permeation through nitrile gloves.

Abstract

The aim of this study was to investigate whether two different brands of unsupported and unlined nitrile gloves protected against aqueous emulsions of a Folpet wettable powder (50% Folpet) using an ASTM type-I-PTC 600 permeation cell at 30.0 +/- 0.1 degrees C held in a shaking water bath. An analytical method to determine Folpet using the internal standard method was first developed based on gas chromatography-mass spectrometry (GC-MS), and gas chromatography-electron capture detection (GC-ECD). A novel pyrolysis GC-ECD technique that quantified the thermal degradation product phthalimide had pg sensitivity suitable to detect the trace amounts of Folpet that permeated. The on-column conversion was (68.0 +/- 9.5) percent at 170 degrees C over the folpet injected mass range of 3 to 148 pg. The challenge solution in the permeation cell was 1.4 mg/mL aqueous emulsion of Folpet wettable powder, and 2-propanol was the collection solvent. After evaporation of the collection solvent, the time weighted average rate of permeation of Folpet through SafeSkin nitrile (an exams type of glove) after 8 hours was (42.1 +/- 2.9) ng/cm(2)/min compared with (2.04 +/- 0.69) ng/cm(2)/min for the Sol-Vex nitrile (industrial chemical resistant), the latter being about 21 times more protective and also near the limits of detection. The respective values after 4 hours of exposure were (28.4 +/- 1.2) and (0.65 +/- 0.36) ng/cm(2)/min. Diagnostic reflectance infrared minima of both challenge and collection sides of the gloves showed small changes in wave number and intensity values after 8 hours of exposure, with Folpet being detected in dried spots on the challenge side. GC-ECD-based permeation and IR reflectance data indicated high chemical resistance of the Sol-Vex gloves to an aqueous emulsion of Folpet.