NCJ Number
145764
Journal
Journal of Forensic Sciences Volume: 38 Issue: 4 Dated: (July 1993) Pages: 950-955
Date Published
1993
Length
6 pages
Annotation
This study was undertaken to determine whether postmortem blood cholinesterase activity could be used as a screening test for exposure to chemical nerve agents.
Abstract
Whole blood cholinesterase activity at 25 degrees C was analyzed for a 1-week period to simulate the battlefield collection problems of hemolyzed blood samples, delayed specimen recovery, and unrefrigerated transfer to a testing facility. A total of 53 nonpreserved, postmortem whole blood specimens were analyzed in triplicate for cholinesterase activity. Results indicated a negligible loss of cholinesterase activity by day 7 of the study. Enzyme activities of specimens had a mean value of 0.48 initially and 0.45 pH units after 1 week. Whole blood from five healthy adults remained essentially unchanged during the study period, with an initial value of 0.59 and a final value of 0.52 pH units. To compare postmortem and simulated nerve agent values, aliquots from 18 of the original 53 postmortem specimens were frozen during day 1 of the study and thawed on day 7 with a cholinesterase inhibitor added. These specimens were then analyzed with the other specimens. All values from inhibited specimens were essentially 0 pH units compared to a range of 0.07 to 0.61 pH units for matched, uninhibited day 7 postmortem specimens. Fifteen nonpreserved specimens from the battlefield were analyzed to verify screen performance, and these results fell within the uninhibited postmortem range above. The authors conclude that cholinesterase activity in postmortem specimens collected within a 1-week period of death can be used as a screen for possible nerve agent exposure. 8 references and 2 tables