Time since discharge of rifles

The estimation of time since the latest discharge of rifles has been achiev ed by the SPME sampling technique and the GC-TEA analytical system. An unid entified compound, designated as the TEA2 compound, was detected in all the rifles investigated. The same compound was observed in shotguns and spent cartridges in our previous work. This compound escapes rapidly from the ins ide of rifle barrels, but can still be detected there one to two months aft er the shooting. The decrease of the TEA2 peak with time after shooting is non-exponential, and the curve-fitting procedure proposed for the estimatio n of time since discharge of shotguns can be applied also for rifles.