Accession Number:

ADA402869

Title:

Low-Level Sarin Vapor Exposure in Rats: Effect of Exposure Concentration and Duration on Pupil Size

Descriptive Note:

Final technical rept. Aug 2000-Sep 2001

Corporate Author:

EDGEWOOD CHEMICAL BIOLOGICAL CENTER ABERDEEN PROVING GROUND MD

Report Date:

2002-05-01

Pagination or Media Count:

40.0

Abstract:

The probability of sarin GB vapor-induced miosis was estimated in rats exposed to various combinations of exposure concentration and duration. Groups of male and female rats Sprague-Dawley were exposed to one of a series of GB vapor concentrations for a single duration 10-240 minutes, in a whole-body dynamic chamber. Separate effective concentrations for miosis defined as a post-exposure pupil diameter 50 or less of the pre-exposure pupil diameter in 50 of the exposed population EC50 and corresponding dose-response slopes were determined, for each exposure time, by the Bliss probit method. Contrary to that predicted by Habers rule, ECT50 values increased with exposure duration i.e., the CT for 50 of the exposed population to show miosis was not constant over time. Linear regression analysis was used to derive a model of low-level GB vapor-induced pupil diameter changes in the rat as a function of exposure concentration and time. Female rats were more sensitive to GB vapor toxicity than male rats. Miosis was the only clinical sign noted following GB vapor exposure. Blood esterase acetylcholinesterase, butyrylcholinesterase, and carboxylesterase activities were not inhibited by exposure to the low-level range of GB vapor.

Subject Categories:

  • Toxicology
  • Chemical, Biological and Radiological Warfare

Distribution Statement:

APPROVED FOR PUBLIC RELEASE