Procedure
Collection of samples. Urine samples from people
with occupational exposure as well as from people with
no known occupational exposure to cadmium were
collected in acid-washed polyethylene bottles and stored
at4#{176}C.
Analysis. To decrease the nonspecific absorption and
dissolve precipitates, we diluted the wines with an equal
volume of 0.3 mol/liter HNO3 and then stored them for
at least 1 h before analysis.1
All digestions and dilutions were done in polystyrene
tubes (Haeger Plastics, Stallarholmen, Sweden), which
previously had been washed with 0.1 mol/liter disodium
ethylenediaminetetraacetate and rinsed with metal-free
water.