NCJ Number
97584
Date Published
1984
Length
8 pages
Annotation
Calcium concentrations in permanent-waved head hair reveal useful patterns to be considered when suspect and control hair samples are compared.
Abstract
Laboratory study examined calcium concentration in human head hair as a function of the distance from the hair root. For growing hairs treated by permanent-waving, the measured concentration of calcium was low up to the distance corresponding to the latest treatment. At that position, the concentration of calcium suddenly increased to a level that remained roughly constant for the remaining part of the hair. Calcium profiles of hairs treated twice displayed rapid increases in calcium concentration at positions corresponding to the expected growth of the hairs. Thus, this analysis permits an estimation of the time elapsed since the last and previous treatments of a hair and should be valuable in forensic comparison of human head hair. The kinetics of calcium uptake by treated and nontreated hair was studied as well as some variations in calcium profiles obtained for the hair of one individual. Experiments with freshly treated hair showed that its calcium content was relatively low but increased rapidly upon repeated exposure to tap water. Calcium profiles obtained for hairs of one individual cannot be exact copies of each other, due to several possible factors. Also, some problems are encountered when the individual hair is in its nongrowing phase. Seven graphs and a list of five references are provided.