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 real problem to be overcome will be the high concentration of acids present when 

 analyzing for additional trace components. 



Continued use of microscale purge and trap with direct sampling of the hand 

 in a Tedlar bag will most likely provide, in the near future, a useful method of 

 removing acids. Though this method is subject to compound discrimination of polar 

 compounds, concentration of sampled air is a desirable attribute. Air trapped in the 

 bag was used for the experiments contained in this dissertation; however, it is not 

 necessary that air be used. Once the hand is enclosed in the bag, the air could be 

 purged from the bag by an inert gas, such as helium. Purge and trap analyses 

 allowed for concentration of highly volatile materials and for removal of the high 

 concentrations of carboxylic acids which interfere with determination of trace 

 components present. 



Quantitation is a dilemma with respect to the bead sampling methods. The 

 actual quantitation by mass spectrometry is not the problem; however, sampling in 

 a consistent manner is. The concentration and presence of components on the skin 

 is not constant and is affected by many variables that have been observed to vary 

 from day to day. One possibility for quantitating known emanations from the skin 

 with direct sampling employing a Tedlar bag might be to coat an area of the skin 

 with a known non-toxic volatile to semi-volatile compound. This may yield some 

 insight about collection efficiency of emanations. Attempts could be made to spike 

 the beads with known concentrations of, for example, lactic acid and additional 



