Occupational asthma induced by inhaled carmine among butchers.

BACKGROUND

Carmine is a natural coloring agent for food and cosmetics. There have been several reports of occupational asthma among employees at factories making natural dyes, however, there are no cases reported among butchers.

OBJECTIVES

We report on two male patients who presented with a history of occupational asthma. Both patients are butchers and used a mixture of additives with carmine as dye in sausages.

METHODS

Skin prick tests were performed with common aeroallergens, commercial mixture additives and separated compound of the additive mixture. Total IgE, metacholine test, specific inhalatory challenge tests with carmine and mites, SDS-PAGE and IgE-immunoblotting were carried out.

RESULTS

Skin tests were positive to mites, additive mixture and carmine in both cases. Specific IgE to mites was positive only in patient one. Bronchial provocation tests were positive to metacholine and carmine and negative to Dermatophagoides pteronyssinus in both cases. IgE-immunoblot showed a specific IgE-binding band at 10 kDa and at a large number of bands along all molecular weights. No inhibition was achieved in carmine-IgE-specific bands with the D. pteronyssinus extract.

CONCLUSIONS

We report on two butchers with occupational asthma due to an IgE-mediated sensitization to carmine. There are several proteins that may act as allergens, and these may be conditioned by the route of exposure and are not cross-reactive with mite proteins. Carmine may be considered to be an etiologic agent in butcher's asthma.