An increasing number of plants for re-use of refuse have been constructed in Denmark in recent years. The Kaastrup Plant near Skive was opened in spring 1986. The plant accepts household rubbish and industrial refuse separately. The refuse is sorted by machine (industrial refuse is sorted partially manually) and in a large partially open machine plant, refuse is converted into fuel pellets. During a period of eight months, eight out of 15 employees developed respiratory symptoms. In seven, bronchial asthma was diagnosed and chronic bronchitis in one person. Four had initial symptoms of the organic dust toxic syndrome. After further six months, another case of occupationally-conditioned asthma occurred in the plant. Only two out of nine had previously had asthma or atopic disease. The investigation did not reveal any evidence of type-I allergy. Six out of nine had specific precipitating antibodies to refuse while all had negative RAST tests to this. In spring 1989, from six to eighteen months after the onset of the symptoms, six had still dyspnoea on exertion and three had positive histamine-provocation tests and seven out of nine had left the plant. Occupational medical measurements revealed dust concentrations of 8.1 mg/cubic millimeter in September 1986 and total germs of up to 3 x 10(9) cfu/cubic meter. Construction of the plant involved considerable contact with the refuse on account of the cleansing processes and open systems and it was reconstructed in the course of 1987/1988 so that the hygienic conditions are now acceptable.(ABSTRACT TRUNCATED AT 250 WORDS)
Wood trimmers are exposed to molds that periodically grow on timber, and may develop acute as well as chronic pulmonary function impairment. This study examined whether these acute changes in pulmonary function are predictors for a longitudinal deterioration in pulmonary function, beyond normal aging and exposure. Across-shift changes in pulmonary function, measured during a working week, were evaluated in 15 wood trimmers with a follow-up time of 27 months. Twenty-six sawmill workers, employed at the same plants as the wood trimmers, served as control subjects. The highest concentration of viable mold spores for the wood trimmers was 10(6) colony-forming units (cfu)/m3, i.e., several times higher than the corresponding value for the sawmill workers. At the follow-up, wood trimmers had a lower forced vital capacity (FVC) on average, after adjustment for age and height, compared to the sawmill workers. In addition, a correlation was found between the across-week change in forced expiratory volume in 1 second (FEV1) and the decline in FEV1 between the first and the second occasion, after adjusting for normal aging in nonsmoking wood trimmers (r2 = 84%, p
Welders are exposed to airborne particles from the welding environment and often develop symptoms work-related from the airways. A large fraction of the particles from welding are in the nano-size range. In this study we investigate if the welders' airways are affected by exposure to particles derived from gas metal arc welding in mild steel in levels corresponding to a normal welding day.
In an exposure chamber, 11 welders with and 10 welders without work-related symptoms from the lower airways and 11 non-welders without symptoms, were exposed to welding fumes (1 mg/m3) and to filtered air, respectively, in a double-blind manner. Symptoms from eyes and upper and lower airways and lung function were registered. Blood and nasal lavage (NL) were sampled before, immediately after and the morning after exposure for analysis of markers of oxidative stress. Exhaled breath condensate (EBC) for analysis of leukotriene B4 (LT-B4) was sampled before, during and immediately after exposure.
No adverse effects of welding exposure were found regarding symptoms and lung function. However, EBC LT-B4 decreased significantly in all participants after welding exposure compared to filtered air. NL IL-6 increased immediately after exposure in the two non-symptomatic groups and blood neutrophils tended to increase in the symptomatic welder group. The morning after, neutrophils and serum IL-8 had decreased in all three groups after welding exposure. Remarkably, the symptomatic welder group had a tenfold higher level of EBC LT-B4 compared to the two groups without symptoms.
Despite no clinical adverse effects at welding, changes in inflammatory markers may indicate subclinical effects even at exposure below the present Swedish threshold limit (8 h TWA respirable dust).
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Cites: Int Arch Allergy Appl Immunol. 1973;45(1):57-604580380
History of acute symptoms (cough, wheezing, shortness of breath, fever, stuffy nose, and skin itching/rash) following exposure to grain dust was obtained from 661 male and 535 female current and former farmers. These symptoms were relatively common: 60% of male and 25% of female farmers reported at least one such symptom on exposure to grain dust. Association of cough, wheezing, shortness of breath, and stuffy nose with skin reactivity and capacity to form IgE is consistent with an allergic nature of these symptoms. Barley and oats dust were perceived as dust most often producing symptoms. On the other hand, grain fever showed a different pattern, i.e., it was not associated with either skin reactivity or total IgE. Smoking might modify the susceptibility to react to grain dust with symptoms. Only those who reported wheezing on exposure to grain dust may have an increased risk to develop chronic airflow obstruction.
OBJECTIVES: This study examined certain occupational exposures and the risk for adult-onset asthma. METHODS: A nested case-referent study of adult-onset asthma was performed on a random population sample (N=15813), aged 21 to 51 years. Cases for the study included 2 groups: subjects reporting "physician-diagnosed" asthma (N=251) and a broader "asthma" group (N=362). The "asthma" group consisted of subjects with "physician-diagnosed" asthma (N=251) and subjects reporting asthma-like symptoms without having "physician-diagnosed" asthma (N=111). The referents (N=2044) were randomly selected from the whole population sample. The case-referent sample was investigated with a comprehensive questionnaire about occupational exposures, asthma, respiratory symptoms, smoking, and atopy. Odds ratios were calculated with stratification for gender, year of diagnosis, and birth year. RESULTS: The highest odds ratio for "physician-diagnosed" asthma was associated with exposure to flour dust [odds ratio (OR) 2.8, 95% confidence interval (95% CI) 1.5-5.2] and the occupational handling of resin-based paints (isocyanates) (OR 3.0, 95% CI 1.6-5.9). Exposure to welding fumes, textile dust, and work with glues containing acrylates was also associated with an increased odds ratio for "physician-diagnosed" asthma. Including persons with asthma-like symptoms (ie, the asthma group) showed similar results. CONCLUSION: This population-based case-referent study from Sweden indicates that occupational exposure to acrylate-based compounds and welding fumes is associated with increased risk for adult-onset asthma.
BACKGROUND: The overall aim of this study was to investigate how airborne house dust particles may contribute to an allergic immune response, and thereby also to asthma and allergic diseases. MATERIAL AND METHODS: Using transmission electron microscopy, we quantified and characterized airborne house dust particles, with regard to elemental and size distribution. Furthermore, an immunogold labelling technique was used to study whether some common allergens were present on the surface of airborne house dust particles. Finally, a mouse model was used to study the adjuvant activity of airborne house dust on the IgE antibody response. RESULTS: A vast majority of the airborne particles samples from homes in Oslo were found to be less than 2.5 microns in diameter, thus they are liable to penetrate deep into the respiratory tree. This PM2.5 fraction contained, in addition to sulphur aerosols and silicates, many soot particles, most of them being less than 1 micron in diameter. These soot particles were found to carry allergens on their surface. We also found that diesel exhaust particles, which is probably a main soot component of airborne house dust, absorbed several wellknown allergens in vitro. Furthermore, the airborne house dust particles were found to elicit a local lymph node response, and to have an adjuvant activity on the production of IgE antibodies to ovalbumin as a model allergen. INTERPRETATION: These results show that indoor suspended particulate matter contains a lot of potential allergen carriers, i.e. soot particles (carbon aggregates), most of them being less that 1 micron in diameter and thereby able to transport allergens deep into the airways. In addition, our results indicate that suspended particulate matter may have an adjuvant effect on the production of IgE to common environmental allergens, and also may provoke a local inflammatory response.
