Prevention of occupational allergies

Abstract

In this paper two occupational risk groups are described as examples of prevention of work-related allergy: operating-room nurses of the Erasmus Medical Center and greenhouse workers in the western part of The Netherlands (the ‘Westland’ region). Natural Rubber Latex (NRL) allergy is an important health-care problem in the western world. Due to increasing use of rubber gloves, more workers in hospitals and laboratories are exposed to latex allergens. Latex hypersensitivity can induce local symptoms after glove use (usually caused by type-IV allergy to rubber additives), as well as more serious type-I allergic reactions ranging from urticaria and rhinoconjunctivitis to asthma and even anaphylactic shock. Prevalence rates of type-I latex atopy are ranging from 2.8 to 16.9 % for hospital personnel. We investigated the prevalence of natural-rubber latex allergy in a population at risk (operating-room personnel) in our hospital. This study was asked for by the Board of Directors in order to evaluate the need for a change in type of glove usage at the operating rooms. Regular OR staff members were tested in 1998 for latex allergy. Questionnaires, serologic testing and skin prick tests with different glove extracts were used. The study group comprised 163 persons (response rate 70 %). Twentythree persons (14.1 %) had specific IgE antibodies against latex. Of these 23 persons, 16 showed work-related type-I allergic symptoms. It was concluded that IgE-mediated allergy to natural rubber latex is a serious problem, also in our institute, and we prompted the Board of Directors to change the glove policy in the entire hospital. During 1999 no more powdered NRL-gloves were purchased. In 1999, an extensive study among bell-pepper growers showed that 35% was sensitized to bell-pepper pollen. Since a few years bee researchers experiment with bees to discard pollen from bell-pepper flowers. We investigated whether bees can reduce the pollen output in bell-pepper greenhouses and whether this reduction results in a decrease of allergic complaints in the greenhouse workers. Eighteen greenhouses participated in the study. The investigators paid three visits to each greenhouse, complaints during work were asked for, skin prick tests were performed, nasal Visual Analogue Scales were obtained and spirometry was done. In each greenhouse pollen was counted. In 6 and 3 of the greenhouses high and low numbers, respectively, of honeybees were placed throughout the pollen season of the sweet bell-pepper plant. It was found that bees reduced pollen counts in a dose-dependent way. Also, a significant trend relationship between Visual Analogue Score in nasal symptoms and exposure to bees was seen. Although the changes in lung function corresponded with the ordering of numbers of bees, statistical significance was not reached. We concluded that the interference of bees in bell-pepper greenhouses significantly reduces the pollen output. Reduction of pollen output decreases the work-related rhinitis symptoms in allergic greenhouse workers. This intervention study demonstrated very clearly that allergic work-related complaints of greenhouse workers, sensitized to bell-pepper pollen, are caused by occupational exposure to this pollen in the greenhouse.