Cobalt is an essential trace element in humans, mainly as
a component of Vitamin B12, cobalamin (Elinder and Friberg,
1986). The current recommended daily intake of cobalamin in
adults in the Nordic countries is 2.0 g/day (Anonymous, 2004),
corresponding to a cobalt requirement of 8 ng/day (Elinder and
Friberg, 1986). High levels of occupational cobalt exposure, usually
through inhalation, are associated with a series of adverse
respiratory health events like asthma, lung fibrosis and possibly
even lung cancer (International Agency for Research on Cancer,
1991), whereas cobalt from alimentary sources rarely is a medical
problem.