Latent Prints
§Latent fingerprints are those that are not visible to the naked eye.  These prints consist of the natural secretions of human skin and require development for them to become visible.
§Most secretions come from three glands:
§Eccrine—largely water with both inorganic (ammonia, chlorides, metal ions, phosphates) and organic compounds (amino acids, lactic acids, urea, sugars). Most important for fingerprints.
§Apocrine—secrete pheromones and other organic materials.
§Sebaceous—secrete fatty or greasy substances.
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