Asthma due to inhaled wood dusts—Western red cedar and Iroko

Summary Occupational type exposure tests with wood dusts provoked specific late asthmatic reactions to Iroko or cedar wood dust in two asthmatic woodworkers respectively. Aqueous extracts gave immediate reactions only to Iroko in the Iroko sensitive patient, who also had precipitins only to the Iroko extract. No skin or serological or inhalation test reactions were given in non‐exposed subjects.