Search

Background: Rhinitis symptoms among bell pepper greenhouse employees can be caused by an allergy to occupational allergens, such as bell pepper pollen and predatory mites, and common inhalant allergens., Objectives: To estimate the effect of sensitization to these allergens on rhinitis-specific quality of life (QoL) during and outside the flowering period and to evaluate whether the QoL of sensitized employees is comparable with that of chrysanthemum greenhouse employees with rhinitis and an average population sample with perennial rhinitis., Methods: We invited 233 employees with rhinitis symptoms to complete 2 rhinitis QoL questionnaires and to undergo skin prick testing with common inhalant allergens and occupational allergen extracts. Multiple regression analysis was used to estimate the impact of sensitization to the various allergens on QoL., Results: Sensitization to bell pepper pollen had a significant negative effect on all the domain and mean QoL scores. The other allergens had no effect on QoL. A significant decrease in all the rhinitis scores was found outside the flowering period. There were no relevant differences in the mean scores of the different domains for both occupational groups. Greenhouse employees scored higher on limitations in activities and much lower on emotional, sleeping, and practical problems compared with individuals with perennial rhinitis., Conclusions: Bell pepper greenhouse employees are impaired in QoL because of their sensitization to bell pepper pollen, suggesting that bell pepper pollen is the most important occupational allergen in greenhouse workers with allergic symptoms. A common allergy does not have more impact on a person's day-to-day life than an occupational allergy; however, there is a clear difference in the way in which an occupational group is hampered compared with a nonoccupational group.

Background: In 1999, an extensive study among bell pepper growers showed that a predatory mite, Amblyseius cucumeris, is a potentially relevant source of occupational allergens because 23% of the population had positive skin prick test reactions., Objective: To investigate whether cross-reactivity between A. cucumeris and Dermatophagoides pteronyssinus is responsible for the cosensitization to both mite species found in 58.7% of A. cucumeris-sensitized greenhouse workers., Methods: Fifteen serum samples from greenhouse workers with work-related inhalant allergy and a positive radioallergosorbent test (RAST) reaction to A. cucumeris or D. pteronyssinus were selected for immunoblot analysis using extracts of both mites. A subselection (n = 5) was used for RAST and immunoblot inhibition to investigate potential cross-reactivity., Results: On immunoblot, 2 distinct patterns were observed: one pattern showed common protein bands in A. cucumeris and D. pteronyssinus blots suggestive of cross-reactivity between A. cucumeris and D. pteronyssinus and the other pattern showed no shared protein bands. Dermatophagoides pteronyssinus RAST inhibition with A. cucumeris extract was low in 4 serum samples (<25% inhibition) and nearly absent in 1 serum sample; A. cucumeris RAST inhibition with D. pteronyssinus extract was high in 1 serum sample (75% inhibition), low in 2 serum samples (35% and <15% inhibition), and absent in 2 serum samples. These results were confirmed by immunoblot inhibition experiments., Conclusions: Amblyseius cucumeris, a new occupational allergen, has species-specific antigens and common antigens that are cross-reactive with the house dust mite D. pteronyssinus.

Background: In a previous investigation, a high prevalence of allergy to sweet bell pepper pollen was found among exposed horticulture workers. Allergy to plant-derived food is often the consequence of primary sensitization to common pollen allergens., Objective: We therefore investigated the cross-reactivity between sweet bell pepper pollen and pollen from grass, birch or mugwort., Method: We selected 10 sera from greenhouse workers who had, besides specific IgE against sweet bell pepper pollen, also IgE to grass, birch or mugwort pollen. Cross-reactivity was tested by the inhibition of IgE binding to solid-phase coupled sweet bell pepper pollen extract. The 10 sera were also analysed for IgE binding to sweet bell pepper pollen by immunoblotting., Results: With these sera, no or small inhibition of IgE binding to sweet bell pepper pollen extract was observed with grass, birch and mugwort pollen. With immunoblotting, major IgE-binding structures were seen at 14, 29 and 69 kDa in sweet bell pepper pollen extract., Conclusion: The results of our study demonstrate that sweet bell pepper pollen contains allergens that have no or limited cross-reactivity with common pollen allergens. With sera from the 10 patients tested, sensitization to sweet bell pepper pollen was not the consequence of primary sensitization to common pollen allergens.

Background: An increasing number of allergic complaints appear to have occurred among Chrysanthemum greenhouse employees. The aim of this study was to estimate the prevalence of work-related allergic symptoms and the prevalence of sensitization to pollen of different members of the Chrysanthemum family., Methods: We studied 104 employees who were invited to answer an extensive questionnaire and to complete a rhinitis quality of life questionnaire. In addition, they were skin prick tested on location with inhalant allergens and home-made pollen extracts of seven different members of the Chrysanthemum family. Radio-allergo-sorbent tests were performed to confirm IgE-mediated reactions., Results: Work-related symptoms were reported in 56.7% of all cases, with the main symptom being rhinitis. Sensitization to Chrysanthemum pollen was found in 20.2% of the employees without one member of the Chrysanthemum family in particular being most prevalent. Sensitization to Chrysanthemum pollen was considered to be an important risk factor for the occurrence of work-related symptoms of the upper airways. Furthermore, inhalant atopy as well as sensitization to common airborne pollen including mugwort were closely associated with sensitization to Chrysanthemum what might be suggestive for cross-sensitization., Conclusions: There is a high prevalence of work-related symptoms in Chrysanthemum greenhouses. In one-third of the employees these symptoms were caused by an IgE-mediated allergy caused by the pollen of the flowers. Inhalant atopy appeared to have a great impact on the development of such a sensitization. Measurements to reduce the pollen exposure are necessary to prevent a further increase of this occupational allergy.

Background: Protection against thrips, a common pest in bell pepper horticulture is effectively possible without pesticides by using the commercially available predatory mite Amblyzeius cucumeris (Ac). The prevalence of sensitization to Ac among exposed greenhouse employees and its clinical relevance was studied., Methods: Four hundred and seventytwo employees were asked to fill in a questionnaire and were tested on location. Next to RAST, skin prick tests (SPTs) were performed with common inhalant allergens, the storage mite Tyrophagus putrescentiae (Tp) which serves as a temporary food source during the cultivation process and Ac. Furthermore, nasal challenge tests with Ac were carried out in 23 sensitized employees., Results: SPTs positive to Ac were found in 109 employees (23%). Work-related symptoms were reported by 76.1%. Sensitization to Tp was found in 62 employees of whom 48 were also sensitized to Ac. Immunoglobulin (Ig)E-mediated allergy to inhalant allergens appeared to be an important risk factor for sensitization to Ac. Employees with rhinitis symptoms showed a significantly higher response to all Ac doses during the nasal challenge test compared with employees without rhinitis symptoms., Conclusions: The predatory mite Ac is a new occupational allergen in horticulture which can cause an IgE-mediated allergy in exposed employees. It is biologically active on the mucous membranes of the nose and therefore clinically relevant for the development of work-related symptoms.

Background: An increasing number of allergic complaints appear to have occurred among bell pepper greenhouse employees., Objective: The aim of this study was to estimate the prevalence of work-related allergic symptoms and the prevalence of sensitization to specific occupational allergens and its determinants., Methods: We studied 472 employees who were invited to answer an extensive questionnaire and to be tested on location with inhalant allergens and home-made extracts of the bell pepper plant. In addition, peak expiratory flow monitoring and RASTs were performed., Results: Work-related symptoms were reported in 53.8% of all cases. Sensitization to the bell pepper plant was found in 35.4%. Positive reactions to leaf, stem and/or juice, however, were associated in nearly 90% with sensitization to pollen, which appeared to be most important allergen of the plant. Sensitization to the bell pepper plant and inhalant atopy were considered the most important risk factors for the occurrence of work-related symptoms of the upper airways (PRR 2.63, CI 2.11-3.25 and PRR 2.25, CI 1.82-2.79) as well as of the lower airways (PRR 4.08, CI 2.38-7.00 and PRR 3.16, CI 1.87-5.33)., Conclusion: There is a surprisingly high prevalence of work-related respiratory symptoms (53.8%) in bell pepper horticulture. In two-thirds of the employees, symptoms at work were associated with an IgE-mediated allergy due to the high and chronic exposure to bell pepper pollen. Complaints at work without specific sensitization to bell pepper pollen can be caused by non-specific hyper-reactivity or atopy to other occupational allergens. The extent of this occupational allergy has important consequences for the health care of this large, still growing occupational group.