determined from the average of five pulses at five different
locations on all 10 nails. For AA, the numbers in parentheses are
the standard deviation of three different determinations using nail
clippings taken from the same subject. The sample identifiers refer
to age and gender. Samples “49F 1” and “49F 2” are taken from two
different 49 year old females.
The determined concentrations of Ca, Mg, and Zn fall within
the (admittedly large) range found in the literature. Calcium in
healthy human nails has been found at concentrations ranging
from less than 100 ppm [3] to over 18,000 ppm [18]. Zinc has been