Comparison of Low-Level Sarin and Cyclosarin Vapor Exposure on Pupil Size of the Gottingen Minipig: Effects of Exposure Concentration and Duration

The effective concentrations of the nerve agents' sarin (GB) and cyclosarin (GF) as a function of exposure duration in the Gottingen minipig were investigated. The dependency of median effective dosage (ECT50) over time was also determined. Two sampling methods used to monitor and analyze the GB or GF vapor concentration in the exposure chamber included a quantitative technique using solid sorbent technique to trap nerve agent, followed by thermal desorption and gas chromatography and continuous monitoring technique using a phosphorus monitor. Physical parameters were monitored during exposure and recorded periodically. Sequential images of eye, under dim light conditions, were digitally captured for analysis and calculation of pupil area using a custom-designed software program. As a group, male minipigs were significantly more sensitive to the pupil constricting effects of GF than were female minipigs.