Occupational immediate‐type asthma and rhinitis due to rhodium salts

BACKGROUND: Whereas platinum salts are well known occupational allergens, rhodium salts have not been identified as inhalative sensitizing substances. METHODS: A 27-year-old atopic operator of an electroplating plant developed work-related shortness of breath and runny nose with sneezing after exposure to rhodium salts. Quantitative skin prick tests (SPT) and bronchial challenge tests with a dosimeter protocol were performed with quadrupling doses of the sodium chloride salts of rhodium (Na(3)RhCl(6)) and platinum (Na(2)PtCl(6)). RESULTS: The patient showed positive SPT reactions and positive bronchial immediate-type reactions with rhodium and platinum salts. Sensitivity to rhodium salt was much higher than to platinum salt; the molar concentrations differed by a factor of 256 in SPT and a factor of 16 in bronchial challenges. CONCLUSIONS: Rhodium salts should be considered as occupational immediate-type allergens.