Contact Allergy in Agricultural Workers

Agricultural workers (n = 121) referred to the Nofer Institute of Occupational Medicine for suspected occupational disease were subjected to dermatological and allergological examinations. All were patch and prick tested with standard occupational and environmental allergen sets. Contact dermatitis was diagnosed in 60 (49.6%) patients. In the women, the dominant allergy was that to nickel, benzalkonium, palladium, cobalt, thimerosal, fragrances and balsam of Peru, while the men were most frequently sensitive to chromates, cobalt, 4-phenylenediamine, fragrances, captan, formaldehyde, 4-aminoazobenzene, wool alcohols and cinnamic alcohol. Phenylmercuric chloride caused allergic reactions in 6 women and 2 men, while 6 workers were sensitive to neomycin. Allergy to glutaraldehyde was diagnosed in 3 workers, to lysol in 4, to chlorhexidine in 1, to chloramine in 1. Three patients reacted to thiurams, 3 to diphenylguanidine, 3 to mercaptobenzothiazole. Of the 9 workers sensitive to 4-phenylenediamine, only 2 men reacted additionally to N-isopropyl-N-4-phenylenediamine. Ziram (zinc dimethyldithiocarbamate) and copper sulfate caused allergy in 1 agricultural worker each. Immediate allergy was diagnosed in 43 (35.5%) patients. The dominant allergens in that category included straw dust, hay dust, wheat threshing, rye pollen and cow epithelium. The final diagnosis was based on the clinical picture and the results of the patch and prick tests. Allergic contact dermatitis was diagnosed in 27 (22.3%), atopic dermatitis in 27, irritant contact dermatitis in 15 (12.4%) and urticaria in 9 (7.5%) agricultural workers. Other dermal diseases were diagnosed in single patients. The clinical examinations showed no dermal lesions in 31 (25.6%) patients.