Hand wash samples control

The main problem associated with the application of gun-shot residue analysis is in the interpretation of the results. Lead is a ubiquitous contaminant of the environment, and little reliance can be placed on the presence of lead removed from the hand of a suspect. Barium and antimony are less commonly found in normal control samples however these elements can be present in hand swabs due to metal working, painting and other normal occupations. Also, the suspect must be apprehended soon after the incident and the swabs taken before the hands are washed. Nesbitt et al. [24]... 

Normally, 10-20 subjects are recruited for each product evaluated. A control product is sometimes used. During a washout period of at least 7 days, subjects are not permitted to use antimicrobial products or expose their hands to known compounds that have antimicrobial properties. The remaining study procedures are identical to those of the healthcare personnel handwash previously described, but the total number of washes is 5-10, with glove juice samples collected at baseline and after wash 1 and wash 5, and after wash 10 if 10 washes are used. The microbial sample counts taken after the test washes are then compared to the baseline values. 

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