Hair collection and measurements procedure
Hair samples were cut at the scalp at 6
different locations on the head.. The total amount
of hair collected from each individual and then
analyzed ranged from 0.1to 0.5g. Hair samples
were rinsed with alcohol followed by triple
rinsing with water and then a repeated rinsing
with alcohol. Washed hair was dried at 105oC.
Dried samples were weighed and then mineralized
using a mixture of concentrated nitric and
perchloric acids (mixed at a ratio of 5:1)until