Re: What is in a fingerprint ?

Dear Tasha,

Good question, and scientists have asked the same question, and several 
set out to find the answer.  Scientists knew for some time that a 
fingerprint left at a scene, called a latent print, consisted of the 
residue left behind when someone touched something.  This residue consists 
mostly of water, about 99%!  The rest of the material consists of fats, 
oils, salts, and in some cases, DNA.  

Over the years, police officers and scientists have noticed that the 
latents left behind by young children disappear faster than those of 
adults, and scientists have speculated that children's latents may have 
more volatile components which evaporate faster.  

I have listed the following articles that you can get from a library which 
should help answer your question as to the specific chemical nature of 
latent prints. I hope this helps.

Dale L. Laux
Forensic Scientist

S. K. Bramble, "Separation of latent fingermark residue by thin-layer 
chromatography," J. Forensic Sci. 40, 969 (1995).

M. V. Buchanan, K. Asano, A. Bohanon," Chemical characterization of 
fingerprints from adults and children," in Forensic Evidence Analysis and 
Crime Scene Investigation, J. Hicks, P. R. De Forest, V. M. Baylor, eds., 
Proc. SPIE 2941, 89 (1997).

R. A. H. van Oorschot, M. K. Jones, "DNA fingerprints from fingerprints," 
Nature 387, 767 (1997).

G. M. Mong, C. E. Petersen, T. R. W. Clauss, "Advanced fingerprint 
analysis project fingerprint constituents," Pacific Northwest National 
Laboratory, Richland, WA 99352, report PNNL-13019, Sept. 1999.

"Vanished Into Thin Air: The Search for Children's Fingerprints", Anal. 
Chem., July 1, 1995, pp. 435A-438A.