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VOL. 70 (4), 961-999, 2004 VANADIUM - AN ELEMENT BOTH ESSENTIAL AND TOXIC

TABLE 6. Vanadium contents of several bulges of roots, stems and tubes
(µg/kg dry matter)

Species (n) xs Species (n) xs

Kohlrabi (25) 29 18 Carrot (34) 71 43
Onion (25) 41 66 Asparagus (7) 99 70
43 107 118 65
Potato without peel (38) 65 55 Leek (14) 471 240
White radish (6) Potato peel (24)

The leaves of all plant species and especially the perennial plants
on which game feeds in winter prove to be extremely rich in vana-
dium (Table 7) (4).

TABLE 7. Vanadium content of several winter grazing of game (µg/kg dry matter)

Species (n) xs Species (n) x s

Pine bork (29) 690 500 Raspberry (10) 1399 913
Spruce bork (17) 854 407 Pine twigs (5) 1626 552
Spruce twigs (8) 1002 523 3111 973
Bilberry herb (3) 1020 327 Heather (8) 3136 350
Oak twigs (3)

The vanadium porphyrin abundant in oil has formed post mor-
tem from chlorophyll. By measurements of the vanadium content in
tree rings, the yearly increase in atmospheric vanadium from vana-
dium-rich gasoline can be mapped (80).

High concentrations of vanadium are also found in a few species
of the mushroom genus Amanita. The vanadium-containing com-
pound found in mushrooms was named amavadine. The physiologi-
cal function of amavadine is unknown. Wever and Krenn (1990)
(132) suggested that amavadine acts as a cofactor with an oxidase or
peroxidase function. Up to now it remains a mystery as to why just
Amanita species have designed such an efficient chemistry for vana-
dium enrichment (81, 23).

Vanadium in plants decreases significantly with increasing age.
From the beginning of May to the middle of June, vanadium con-
tents were found to abate to a third of the initial level (Table 8).

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