A preliminary report of a surveillance scheme of occupational asthma in the West Midlands.

The results from the first year of a notification scheme for occupational asthma in the West Midlands Region are presented. The scheme includes recognised new and old cases of occupational asthma. Thirty new cases were recognised per million general working population in the first year. Cases recognised in different occupational groups ranged from 154 per million painters and assembly workers to three per million clerical staff. Analysis of the agents to which workers with recognised occupational asthma were exposed identified commonly recognised agents such as isocyanates, colophony, and flour and generally less well recognised ones such as oil mists. The distribution of new and old reported cases, including those receiving compensation from the Department of Social Security, were calculated by health authority using estimated working population as the denominator. The number of reported cases varied from 303 per million in a semi-urban health authority that has a respiratory physician with a special interest in occupational asthma to less than 30 cases per million in eight health authorities. The most likely cause for these differences is lack of ascertainment.