Asthma caused by occupational exposure to vanadium compounds.

Four workers from a recently established vanadium pentoxide refinery in Western Australia presented with green discoloration of the tongue, upper respiratory symptoms, and asthma. Three of them were non-atopic as judged by history, prick skin test responses, and total serum IgE levels. The two with most recent exposure to vanadium compounds exhibited bronchial hyperreactivity to histamine. Vanadium compounds appear to be capable of inducing asthma in previously normal subjects. One subject continued to wheeze eight weeks after this last exposure.