Table - link µmoles/gram of dry hair
||Human Homo sapiens
||Robbins, Clarence R. Chemical composition, pp.39-68, chapter 2 in the book Chemical and physical behavior of human hair / Clarence R. Robbins.-2nd ed (2002) p.43 table 2-2
|| Robbins, e.R., and Kelly, e.H. Amino Acid Composition of Human Hair, Textile Res. J. 40, 891 (1970) link  Ward, W.H., and Lundgren, H.P. In "Advances in Protein Chemistry," Vol. 9, and references therein, Academic Press, New York (1955)  Clay, R.e., Cook, K., and Routh, J.I. Studies in the Composition of Human Hair J. Am. Chem. Soc. 62, 2709 (1940)  Simmonds, D.H. The Amino Acid Composition of Keratins: Part V: A Comparsion of the Chemical Composition of Merino Wools of Differing Crimp with that of Other Animal Fibers Textile Res. J. 28, 314 (1958) link  J. H. Bradbury, G. V. Chapman, A. N. Hambly & N. L. R. King. Separation of Chemically Unmodified Histologica Lcomponents of Keratin Fibres and Analyses of Cuticles. Nature volume 210, pages 1333–1334 (1966) link
||Primary source  abstract: "Samples of hair from five different female Caucasians were selected, while attempting to eliminate or minimize variables introduced by factors, suggested in previous literature, related to genetics, malnutrition, and cosmetic alteration, to analyze for 18 amino acids." Primary source  p.2709 right column top paragraph: "The hair was cleaned and defatted by washing in benzene, dried in a vacuum oven for three to five hours at 65-70°, and stored in a vacuum desiccator over phosphorus pentoxide until analyzed. Total nitrogen was determined by the macro-Kjeldahl method. Total sulfur was determined gravimetrically by the Benedict-Denis method after preliminary oxidation with concentrated nitric acid, as suggested by Wilson and Lewis [ref 4]. Cystine was determined by the Sullivan [ref 6] and Shinohara [ref 7] methods, and cysteine by the methods of Shinohara [ref 8] and Lavine [ref 9]. The hair was hydrolyzed with 20% hydrochloric acid for ten hours in an electric oven at 124-127°. The hydrolysates were decolorized with kaolin."
||P.43 top paragraph: "Table 2-2 summarizes results from several sources describing quantitative whole fiber analyses of these 21 amino acids. These same amino acids are grouped according to functional group and summarized in Table 2-3 [BNID 116949]." P.44 3rd paragraph: "Table 2-2 shows substantial variation in the quantities of some of the amino acids, notably aspartic acid, proline, cystine, and serine, while considerably less dispersion is indicated for other amino acids, primarily valine, glutamic acid, glycine, alanine, leucine, and arginine." P.44 bottom paragraph: "The variation of cystine and cysteine in human hair has been studied extensively. Clay et al. [primary source 14] quantitatively analyzed hair from 120 different persons for cystine and cysteine (see Table 2-2). The hair in this study was selected from both males and females of varying age and pigmentation. Analysis was by the hydrolytic method of Shinohara [ref 31]."