Occupational asthma, rhinitis and contact urticaria in greenhouse workers

Abstract

<b>Background:</b> Aim is to describe greenhouse workers’ occupational allergic diseases and increase the understanding of their nature. <b>Methods:</b> Systematic search from the patient register of Finnish Institute of Occupational Health identified 28 workers from tomato or cucumber growing greenhouses with diagnosis of allergic diseases from 2002 to 2020. We used skin prick tests and serum specific-IgE to detect occupational sensitization. Specific inhalation challenge (SIC) or workplace peak expiratory flow monitoring established occupational asthma (OA), nasal allergen challenge occupational rhinitis (OR), and open skin test occupational contact urticaria (OCU). <b>Results:</b> Most patients had more than one occupational allergic disease and were sensitized to several workplace agents.&nbsp;We identified fourteen OA cases, of which tomato plant caused four cases and cucumber plant three. Pest control orgnisms Amblyseius swirskii and mixture of parasitic wasps Encarsia formosa and Eretmocerus eremicus induced both two SIC-verified OA, while in three patients OA was related to storage mites. Additionally, we diagnosed nineteen OR caused by tomato, cucumber insects or mites, and fourteen OCU caused by tomato or cucumber. Three patients had systemic sting reaction to bumblebee. <b>Conclusion:</b> Cultivated plants, biological pest control organisms and storage mites may cause OA and OR, while OCU was induced only by cultivation plants. Cucumber and Amblyseius swirskii are novel causes of OA. Preventive measures in workplaces and regular health surveillance are needed to prevent allergic occupational diseases among greenhouse workers.