Cadmium metabolism in man

The time course of the fall in blood cadmium concentrations after cessation of exposure has been measured in nine workmen exposed to cadmium. When the initial blood cadmium concentration was below 180 nmol/l (six subjects) it declined smoothly and roughly exponentially, with a mean half-life of 20.4 months and a final asymptote of 70 nmol/l; in the remaining three subjects (initial blood cadmium concentration above 180 nmol/l) the decay was less regular and more prolonged (mean half-life 31.4 months, final asymptote 92 nmol/l). The significance of these results in relation to occupational cadmium exposure is discussed.