Total free amino acids, ammonia, and protein in the sweat of children.

The concentrations of total free amino acids, ammonia and protein in sweat of 44 children, 20 males, and 24 females, 6 to 8 years old, were determined. The children were divided into three groups according to their height, weight, and body weight/height ratio; group I children had heights and weights below the 10th percentile for their age, group II had heights and weights between the 10th and 90th percentile, and group III had heights and weights above the 90th percentile. Sweating was induced by allowing the child to be moderatley active. The temperature at the time of the experiment was 31 to 33 C and the relative humidity 48%. The mean concentrations of total free amino acids (mg/100 ml) in sweat from groups I, II, and III children were 318.9 +/- 52.5, 293.9 +/- 82.9 and 265.1 +/- 57.0, respectively. Alanine, glycine, phenylalanine, threonine, and serine were the principal amino acids in sweat. The concentrations of ammonia in the sweat of group I, II, and III children were 6.90 +/- 2.97, 2.35 +/- 0.81, and 1.17 +/- 0.48 mg/100 ml, respectively. Protein concentrations were 44.15 +/- 14.07, 40.70 +/- 16.60, and 35.75 +/- 5.46 mg/100 ml, respectively.