ABSTRACT
Introduction .................................................................................................... 64 Skin Anatomy.................................................................................................. 64
The Epidermis .......................................................................................... 65 The Dermis............................................................................................... 65
Secretory Glands ............................................................................................. 68 Eccrine Glands ......................................................................................... 69
Inorganic Compounds...................................................................... 69 Amino Acids ...................................................................................... 70 Proteins .............................................................................................. 71 Lipids.................................................................................................. 72 Miscellaneous Constituents .............................................................. 72
Sebaceous Glands..................................................................................... 73 Lipid Origin and Breakdown ........................................................... 75 Chemical Composition of Sebum ................................................... 76 Fatty Acids ......................................................................................... 76 Phospholipids .................................................................................... 78 Wax Esters.......................................................................................... 79 Sterols ................................................................................................. 79 Squalene ............................................................................................. 80 Miscellaneous Organic Compounds................................................ 80
Apocrine Glands ...................................................................................... 80 Variation of Sebum Composition With Age of Donor................................ 81
Newborns.................................................................................................. 82 Young Children ........................................................................................ 83 Adolescents ............................................................................................... 83 Post-Adolescence...................................................................................... 84
The Composition of Latent Print Residue.................................................... 85 United Kingdom Home Office................................................................ 85 Oak Ridge National Laboratory.............................................................. 86 Pacific Northwest National Laboratory.................................................. 87 Savannah River Technical Center Research............................................ 89 Forensic Science Service .......................................................................... 90
DNA From Latent Prints................................................................................ 91 DNA From Blood Prints and Stains....................................................... 91 DNA From Developed Latent Prints...................................................... 92
Miscellaneous Compounds and Contaminants ........................................... 93 Conclusions ..................................................................................................... 94 References ........................................................................................................ 95
The composition of human perspiration has been studied and reported extensively in the medical literature. The medical community has analyzed sweat for many purposes, including attempts to diagnose certain diseases, such as cystic fibrosis, and studies of skin conditions, such as acne. Even the perfume and cosmetics industry has an interest in determining the precise chemical nature of perspiration and how it might interact with their personal hygiene products. However, the information ascertained in these studies does not begin to address the issue that is most critical for forensic scientists. Knowing the precise contents of the various skin glands does not accurately represent the nature of what is actually secreted onto substrates from the fingers and palms. In operational scenarios, numerous contaminants are present in the fingerprint deposit, including material from other glands, cosmetics, perfumes, and food residues. In addition, the secreted material is almost immediately altered by oxidative and bacterial degradation mechanisms. These factors are particularly important since crime scene technicians seldom encounter latent print deposits immediately after they are deposited by a perpetrator. However, there is little information available that describes how a latent print deposit changes with time. Thus, a more thorough understanding of these transformations would allow forensic scientists to develop specific reagents for visualizing compounds known to be stable for long periods of time.
