A metal taste and a greenish colored tongue represent characteristic signs of massive dust contamination of the workplace and inefficient individual protection gears.

Swallowing of inhaled particles can be responsible for minor digestive symptomd like :

-heart burns -loose stools quickly reversible at the end of exposure.

- Skin effects :

Cases of exzema-like dermatitis were reported in a Swedish study, around respiratory protection masks, hands, wrists and forearms, but only one worker tested positive to 2% sodium metavanadate in water skin test. No other publication reports confirmed allergy to vanadium, the sensitizing capacity of the metal appears improbable.

-Respiratory effects :

Repeated exposure to dust and fume can cause airways irritation and asthma-like symptoms and signs.

E.N.T. pathologies may be :

-rhinitis -pharyngitis and/or laryngitis.

Biopsies of the nasal mucous membrane showed a nonspecific inflammatory process.

Respiratory disorders may include :

-cough -thoracic wheezing or -delayed dyspneic (shortness of breath) crises -long term nonspecific bronchial hyperreactivity which corresponds to the definition of asthma caused by repeated exposure to peaked concentrations of irritating vapors or fumes, or Reactive Airways Dysfonction Syndrome (RADS).

Systemic effects :

All of the well controlled studies which attempted to demonstrate neurological, cardiovascular or other effects, proved to be negative.

Genotoxicity and carcinogenesis :

Experimentally :

Vanadium and compounds do not appear genotoxic; they are not mutagen nor cancerogenic.

In man :

No surmortality due to cancer, in particular bronchial, has been observed in the industrial setting.

Reproduction :

Experimentally :

Reproduction toxicity studies in the rat and the mouse are negative when the amounts used are nontoxic to the mother. As for sodium metavanadate, maternal toxicity is observed following a dose of 7.5 mg/kg/day, while embryofoetotoxicity is observed with doses greater than 15mg/kg/jour.

In man :

In man, there is no indication that vanadium can influence reproduction unfavourably.

Exposure :

The VEMP for vanadium pentoxide is 0.05 mg/m3 expressed as V2O5, for fume and respirable dust, in Quebec.

Avoidance of processes generating unnecessary dust is also importan. To this, we may add work in closed systems and improvement of the general ventilation.

Adequate equipment of respiratory protection should be worn during handling of vanadium compounds, and during cleaning of equipment which burns coal or mineral oils as in power stations.

Workers in confined places, as in boilers , must wear acid-proof clothing well fitted to the wrists and ankles, with adequate gloves and rubber boots. Good personal hygiene is necessary and double lockers should be available to separate working clothes from personal clothing.

Medical surveillance :

Clinical monitoring of exposed workers may include periodical spirometric measurements.

It may also include urinary biometrology which reflects the exposure that occurred in the previous 2 or 3 days.

The biological exposure index used in France is 50µg/g of creatinine.

Some authors propose the use of skin testing to screen those who would be sensitized to vanadium compounds, but this possibility seems very rare according to french authors.

References :

1-Occupational Medicine, Carl Zenz, last edition. 2-Occupational & Environmental Medicine, Joseph LaDou, last edition. 3-Chemical Hazards of the Workplace, Proctor & Hughes, last edition. 4-Sax's Dangerous Properties of Industrial Materials, Lewis C., last edition. 5-Clinical Environmental Health and Toxic Exposures, Sullivan & Krieger, 2001 5-Industrial Chemical Exposure, Lauwerys & Hoet, last edition. 7-Toxicologie Industrielle et Intoxications Professionnelles, Lauwerys R.,1999 8-Encyclopedie Medico-Chirurgicale- Toxicologie-Pathologie Professionnelle Paris, Testud F.; septembre 2001.