Permeation of Comite® through protective gloves

Abstract

The goal of the study was to assess how protective disposable (Safeskin®) and chemical protective (Sol-Vex®) nitrile gloves were against Comite® emulsifiable concentrate formulation containing propargite (PROP) as active pesticidal ingredient because there were no explicit recommendations for the gloves that should be worn for hand protection. The glove material was exposed in ASTM-type I-PTC-600 permeation cells at 30.0±0.5°C, and gas chromatography–mass spectrometry used for PROP analysis. Aqueous solutions of Comite® at 40.4mg/mL permeated both Safeskin® and Sol-Vex® nitrile by 8h. Safeskin® showed a mean PROP mass permeated of 176±27μg after 8h compared with a mean mass permeated for Sol-Vex® of 3.17±4.08μg. Thus, Sol-Vex® was about 56 times more protective than Safeskin® for an 8-h exposure. However, the kinetics of the permeation revealed that Safeskin® can be worn for at least 200min before disposal. When undiluted Comite® challenged both types of nitrile, much faster permeation was observed. Safeskin® gloves showed two steady state periods. The first had lag times (tl) values of about 1h, although normalized breakthrough times (tb) were <10min. The second steady state rate (Ps) was on average four times the rate of the first period, and the second steady state period tl was about three times as long as that of the first steady state period, and about the same tl as for the aqueous solution. Sol-Vex® gloves exposed continuously to undiluted Comite® permeated above the normalized breakthrough threshold beyond 2.7h. A risk assessment revealed that the PROP skin permeation rate of 7.1ngcm−2h−1 was much slower than the first steady state Safeskin® glove Ps of 62,000ngcm−2h−1. Infrared analysis showed that the glove surfaces were not degraded by the Comite® challenge. The chemically protective Sol-Vex gloves protected adequately against undiluted formulation for about 2.7h, whereas they provided protection for nearly 8h when the formulation was diluted with water to the highest concentration for field application. In contrast, the disposable Safeskin gloves did not protect at all for the undiluted formulation, but did for 200min when the formulation was diluted with water to the highest concentration for spraying.