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Trace Elements in Abiotic and Biotic Environments
installations and areas involved in military combat operations and training may have
higher concentrations of W, as a result of the use of military hardware containing
this metal (ATSDR 2005c).
Acute toxic reactions were observed from W dissolved in alcoholic drinks, following a tradition of French army artillery recruits, to drink wine or beer which
has rinsed a recently fired gun barrel. The symptoms of this acute intoxication were
sudden nausea on ingestion, onset of seizures, rapid onset of clouded consciousness
leading to coma and encephalopathy, moderate renal failure progressing to acute
tubular necrosis with anuria, and hypocalcemia (Voet van der et al. 2007).
There is little information on W in foods. Its concentration is low, and range from
0.005 to 0.05 mg/kg in vegetables, and from <0.0003 to 0.004 mg/kg in rice. Wines
contained W from 0.00001 to 0.001 mg/kg (Szefer and Grembecka 2007). Limited
available information indicates that levels of W in food are expected to be low.
The total W intake by the general U.S. population cannot be accurately estimated,
due to the lack of data regarding W content in food and drinking water (ATSDR 2005c).
52.7 ANIMALS
In animals, W compounds have the potential for causing adverse health effects
involving the gastrointestinal tract and central nervous system. These effects have
not been observed in humans. Chronic exposure to W compounds may result in permanent lung damage. Soluble forms of W, such as tungstate ions, are more bioavailable to fish and animals than insoluble forms.
Bioavailability of W and its compounds increases in the order of W metal <
W carbide < W ions. It may preferentially occupy enzyme sites, normally reserved for
the essential element, Mo, because Na tungstate may antagonize the normal metabolic
action of Mo, in its role as cofactor for some enzymes, such as xanthine dehydrogenase,
sulfite oxidase, aldehyde oxidase, and xanthine oxidase (secreted in animal milk).
Animals fed with W-containing diet have reduced activities of the Mo-containing
enzymes, xantine oxidase and sulfite oxidase. Guinea pigs treated orally or intravenously with W suffered from anorexia, colic incoordination of movement, trembling,
dyspnea, and weight loss (Gbaruko and Igwe 2007).