The abundance of some elements in hair and nail from the Machakos District of Kenya.

Hair and nail samples collected from a population group in the Machakos District, Kenya, were studied for their elemental content using instrumental neutron activation analysis. In order to test for the type of probability distribution, frequency histograms of elemental concentration of 9 elements in hair, both for male and female subjects in the population, were plotted and chi 2-tests applied for normal distributions. Plots of cumulative frequency, using logarithmic probability paper, were used to illustrate the lognormal nature of the distributions of elements in hair such as Hg. Arithmetic and geometric means with respective standard deviations are presented for 15 elements in hair, divided into four groups according to age and sex. Results from nail samples available for a small number of subjects are also presented for males and females. Differences in concentrations for the various groups were investigated and discussed. Comparison was made with published data for a number of different populations.