Eccrine gland secretions from pores on the palms of the hand and soles of the feet partially contain organic components such as urea, lactic acid, and amino acids. Ninhydrin reacts with these amino acids, eventually resulting in what is commonly termed Ruhemann's purple. Ninhydrin, however, presents problems when fingerprints are associated with inks in the form of handwriting or from mechanically printed devices. In the traditional use of ninhydrin to enhance fingerprint ridge detail ninhydrin crystals are dissolved in solvents such as acetone, petroleum ether, heptane, or even ethyl ether. Acetone causes inks to bleed. Although petroleum ether or heptane are fine replacements for acetone, causing very little running/bleeding of ink, if handled carelessly they can create laboratory safety concerns. In 1996, 3M introduced its hydro-fluroether (HFE), 1-methoxy-nonafluorobutane (HFE-7100), commercially. Being volatile, nonflammable, environmentally safe, and having low overall toxicity, along with being compatible with inks, apparently makes this solvent an ideal carrier for ninhydrin. 2 figures and 11 references