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MANFRED ANKE AN. R. ACAD. NAC. FARM.

The vanadium concentration in children’s hair indicated the va-
nadium pollution very well and better than that in nails (75). For the
identification of the vanadium status, all organs are suitable, and
especially the blood (59, 106). The highest levels of vanadium are
stored in bones, kidneys, spleen and ovary, the lowest in the aorta,
hair, muscle and, especially, in milk (Table 14).

Excretion and Balance of Vanadium

Animals and humans excrete most of the consumed, unabsorbed
vanadium with the faeces (25). The absorbed vanadium is removed
from the body mainly with urine and milk (3) and partly with bile (29).
The biological half-life of vanadium excreted in urine is 20-40 hours.
Animal studies indicate that the elimination of vanadium from the
body following inhalation of vanadium oxides is biphasic, with an
initial rapid elimination (10-20 hours) and a longer terminal phase
(40-50 days) (103, 78). Rats excrete 8 and 10% of injected vanadium
with the faeces and bile, respectively (133, 62). The elimination half-
lives of vanadium in rats were found to range between 11 and 132
hours for soft tissues and 376 hours for the bone. During the first day,
49% of the dosage was eliminated with the urine and 8% with the
faeces (1). The half-life for the elimination of vanadium from the bo-
dies of vanadium-fed diabetic rats was found to be about 12 d (101).

Faecal excretion of the nutritional vanadium intake amounts to
96% in men and non-lactating women, and to 79% in lactating
women (Table 15). Most of this vanadium is not absorbed. The form
of diet (mixed or ovo-lacto-vegetarian) (Table 15) has no influence
on the faecal excretion rate. On average, adults of both sexes and
with either form of diet eliminate 4% of the nutritional vanadium
intake renally (range: 2-6%).

The mean apparent rate of vanadium absorption by adults of
both diet forms amounts to 10%, and the mean vanadium balance is
+ 6%, with a variation between + 23 and – 15%.

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