• Allergy
• Occupational asthma

The increasing awareness of problems with chemical pesticides used in greenhouses has led to a widespread use of biological control measures such as beneficial arthropods and microbiological pesticides. However, exposure to microbiological pesticides may confer a risk of immunoglobulin E-mediated sensitization.1 In a study by Baelum et al including 456 greenhouse workers, skin rash, nose and eye symptoms were seen in persons developing sensitization towards beneficial predatory mites during the 3-year study period and Groenewoud et al found a prevalence of 23% of sensitization to Amblyseius cucumeris in a cross-sectional study of 472 Dutch greenhouse workers.2 3 The predatory beneficial mites A cucumeris and Amblyseius californicus is known to cause sensitization and allergic symptoms from the skin, nose and eyes, but so far no case of occupational asthma caused by these predatory mites has been reported.

A 34-year-old male gardener, a non-smoker, was referred to our Department of Occupational and Environmental Health. The previous 10 years, he had been working in a tomato and green pepper nursery. During …