The accuracy of cadmium determination in human
urine is difficult to ascertain because no certified
method or urine standard exists. Some might argue that
urine control materials are commercially available.
However, these have drawbacks because they are prepared
by adding an inorganic cadmium salt to urine,
which implies that the cadmium probably is not to be
found bound to the same type of compounds as after in
vivo uptake. However, the analytical recovery of cadmium
added to urine was, for >5 nmol/liter, about 100%
(Table 3), which implies good accuracy for our method.
Furthermore, results by another new method (15)
agreed well. That method, in turn, has shown good
agreement with a recently developed method for neutron
activation analysis (Sj#{246}strand, to be published).