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Biomedical subjects

H Nordman

Publications and source records attributed to H Nordman.

At least 37 records · Page 2Linked to original sources
PubMed1998

Diethanolamine-induced occupational asthma, a case report.

BACKGROUND: Amino alcohols are low molecular weight chemicals used widely in industrial processes, often as minor constituents. They have been found to cause allergic contact dermatitis. Marked exposure through airways is uncommon in other than occupational settings where chemicals containing amino alcohols may be heated or vaporized, liberating free amino alcohols into the ambient air. A few cases of asthma and allergic rhinitis have been reported, but the amounts inducing the airway reactions have not been defined. OBJECTIVE: To further characterize ethanolamine-induced asthma and define the concentration inducing the asthmatic reaction, a case of diethanolamine-induced occupational asthma in a patient handling diethanolamine containing cutting fluid is reported. METHODS: Suspicion of work related asthma was raised by symptoms and peak expiratory flow monitorings at work and at home. Specific bronchial provocation tests with the cutting fluid containing DEA and with DEA aerosol at two different concentration below the American Conference of Governmental Industrial Hygienists threshold limit value of DEA (2.0 mg/m3) were done. RESULTS: DEA caused asthmatic airway obstruction at two different concentrations below the ACGIH TLV. A slight dose-response relationship was observed. Specific IgE-antibodies against DEA could not be found. CONCLUSIONS: DEA is able to induce occupational asthma by a sensitization mechanism, the exact pathophysiological mechanism of which is not known.

Adult↗
PubMed1998

Occupational respiratory hypersensitivity caused by preparations containing acrylates in dental personnel.

BACKGROUND: Allergic contact dermatitis caused by acrylate compounds is common in dental personnel; they also often complain of work-related respiratory or conjunctival symptoms. OBJECTIVE: The aim of the present study was to report the cases of acrylates induced respiratory hypersensitivity in dental personnel diagnosed in Finland during the last 6 years. METHODS: Occupational asthma, rhinitis, laryngitis and pharyngitis cases were diagnosed according to patient history, PEF monitoring, and a work-simulating provocation test. RESULTS: Twelve cases of respiratory hypersensitivity caused by acrylates diagnosed in dental personnel (six dentists and six dental nurses) in 1992-97 are reported. During this period one case of conjunctivitis and one of laryngitis have been published separately. Nine cases of occupational asthma, two rhinitis cases, and one laryngitis case were verified according to the challenge tests with dental acrylate compounds (acrylates, methacrylates and epoxy acrylates). Only three patients had positive skin-prick test reactions to common environmental allergens, and none reacted to acrylates in the skin-prick tests. Five patients had an elevated total IgE (>110 kU/L). PEF follow-up showed an occupational effect in all examined eight patients with diagnosed asthma. The mean duration of exposure to acrylates was 22 years, and the duration of respiratory symptoms 8 years. CONCLUSIONS: The results indicate that acrylates constitute an important hazard for dental workers. The mechanism of respiratory hypersensitivity is still unknown, and it is probably not IgE-mediated.

Acrylates↗
PubMed1998

Respiratory health of cigar factory workers.

OBJECTIVES: To determine whether occupational exposure to raw tobacco causes respiratory or allergic diseases, an excess of respiratory symptoms, a decrease in lung function, or parenchymal changes in chest radiography among Finnish cigar workers. METHODS: This cross sectional study included all Finnish cigar workers (n = 106) exposed to raw tobacco and also a group of unexposed matched referents. Data were collected with a self administered questionnaire, flow volume spirometry, measurements of diffusing capacity of the lung for carbon monoxide, chest radiography and skin prick tests. A questionnaire was also sent to former workers of the factory. RESULTS: There were no significant differences between the groups in the prevalence of respiratory symptoms and chest radiography findings. Nine of 102 tobacco workers had pulmonary fibrosis of at least 1/0 (according to the International Labour Organisation (ILO) 1980 classification) and the corresponding figure was five for the referents. The tobacco workers tended to have a low forced vital capacity (FVC), and they had impaired forced expiratory volume in 1 second and lower means of the maximal expiratory flow at 25% of the FVC significantly more often than the referents. Diffusing capacity tended to be lower among the referents. The referents more often had atopy and earlier atopic diseases than the exposed workers. These results indicate the possibility of selection among the exposed workers. CONCLUSIONS: No excess of prevalence of respiratory symptoms in the tobacco workers was found. According to the questionnaire episodes of allergic alveolitis may have occurred in the cigar factory workers. However, in the absence of impairments in lung function and radiological changes it was not possible to distinguish humidifier fever and allergic alveolitis. In exposure conditions that include humidification of the air humidifier, fever and allergic alveolitis constitute a risk for tobacco workers. No effects were shown of exposure to tobacco dust on lung function.

Adult↗
PubMed1998

Progression of asbestosis predicts lung cancer.

STUDY OBJECTIVES: To explore whether the progression of asbestosis correlates with the risk of lung cancer among patients with asbestosis. DESIGN: A group of 85 asbestosis patients (78 men and 7 women) were radiographically followed up between 1979 and 1987. Two or three posteroanterior radiographs taken from each patient in 1978 to 1979, 1983 to 1984, and 1986 to 1987 were classified according to the International Labour Office 1980 classification and were used to divide the patients into progressors and nonprogressors. Follow-up for cancer was done automatically through the files of the Finnish Cancer Registry from the time of determination of the progression status to December 31, 1994. Predictors of lung cancer risk were studied with a logistic regression model, and the standardized incidence ratio (SIR) was calculated for lung cancer. RESULTS: Of the 24 male patients with progressive small opacity profusion, 11 (46%) developed lung cancer, as opposed to 5 (9%) of the 54 male patients without progression. The SIR for lung cancer was 37 (95% confidence interval, 18 to 66) for the progressors and 4.3 (1.4 to 9.9) for the nonprogressors. In both groups, all the lung cancer cases occurred among smokers or ex-smokers. None of the seven female patients showed progressive small opacity profusion. One of them developed lung cancer. In the logistic regression model including all 85 asbestosis patients, radiographic progression of small opacity profusion (p=0.0009) and current smoking (0.0021) were significant predictors of lung cancer morbidity. CONCLUSIONS: Asbestosis patients with radiographic progression of small opacity profusion over a few years are at a higher risk of lung cancer than those with a less aggressive course of the disease. The progression of pulmonary fibrosis may be an independent risk factor that, in addition to smoking history and the intensity of asbestos exposure, could be used to estimate lung cancer risk.

Adult↗
PubMed1997

Mucus glycoproteins from pig gastric mucosa: identification ofdifferent mucin populations from the surface epithelium.

Pig gastric mucins were isolated from the surface epithelium of the cardiac region, corpus and antrum using density-gradient centrifugation after extraction in 6 M guanidinium chloride. In CsCl/0.5 M guanidinium chloride, mucins solubilized from the cardiac region appeared as a broad unimodal band at 1.52 g/ml whereas those from the corpus and antrum occurred as high- and low-density populations at 1.50 and 1.45 g/ml respectively. High-iron diamine reacted more strongly with the cardiac mucins and the high-density populations from corpus and antrum than with the two low-density ones. In keeping with this, approx. 60% of the oligosaccharides from the former mucins and 20% from the latter contained sulphate. All surface epithelial cells of the cardiac region stained with high-iron diamine, whereas in the corpus only the epithelium in the bottom of the pits reacted, suggesting that the high-density population from this region originates from these cells. Mucins from all regions were composed of subunits, each containing highly glycosylated domains. The mucins from the cardiac region were larger than those from the corpus and antrum, and reduced subunits as well as high-molecular-mass glycopeptides from the cardiac mucins were larger than the corresponding fragments from the other regions. Ion-exchange HPLC showed that reduced subunits from the cardiac mucins and the high-density populations from the corpus and antrum were more 'acidic' than reduced subunits from the two low-density ones. All mucins contained a 'neutral'fraction, in particular those from the antrum. Pig gastric mucus thus contains a number of distinctly different mucin populations varying in buoyant density, size, 'acidity', glycosylation, sulphation and tissue origin.

Animals↗
PubMed1997

Glycosylation differences between pig gastric mucin populations: a comparative study of the neutral oligosaccharides using mass spectrometry.

Five mucin populations were isolated from the cardiac region,corpus and antrum of pig gastric mucosa. The released neutral oligosaccharides were permethylated and analysed using high-temperature gas chromatography-mass spectrometry (GC-MS) as well as matrix-assisted laser-desorption mass spectrometry (MALDI-MS). Thirty different oligosaccharides with up to six monosaccharide residues were characterized using both techniques, but the presence of an additional 49 structures was suggested on the basis of their molecular mass by MALDI-MS. Oligosaccharides based on core-1 (Galbeta1-3GalNAcalpha1-) and core-2 [Galbeta1-3(GlcNAcbeta1-6)GalNAcalpha1-] structures were widely distributed, whereas core-3 structures (GlcNAcbeta1-3GalNAcalpha1-) were present only in mucins from the cardiac region and corpus, and core-4 structures [GlcNAcbeta1-3(GlcNAcbeta1-6)GalNAcalpha1-] were present exclusively in mucins from the cardiac region. Furthermore the oligosaccharides from one of the mucins from the corpus were significantly longer than those from the other populations. The results illustrate vast structural diversity, but the relative abundances show only a few dominating structures, suggesting that many oligosaccharides may be quite rare in pig gastric mucins. Well-defined mucin populations with distinctly different glycosylation can thus be identified in pig stomach, suggesting that glycosylation of the large secreted mucins from this tissue is not a random event.

Animals↗
PubMed1997

Occurrence of asthma and chronic bronchitis among female hairdressers. A questionnaire study.

We carried out a retrospective cohort study using a self-administered questionnaire to assess the risk of hairdressers to develop asthma and chronic bronchitis. A representative sample of 4433 female hairdressers and an equal number of shop personnel in employment in 1980 was drawn from the Longitudinal Census Data File of Statistics Finland. Physician-diagnosed asthma, chronic bronchitis, and other respiratory diseases in 1980 and 1995 were inquired about in the respiratory part of the questionnaire. The response rate to the questionnaire was 82% for the hairdressers (n = 3484) and 79% for the referents (n = 3357). The prevalence of asthma among the hairdressers was 5.6% in 1980 and 10.1% in 1995, and the prevalence of chronic bronchitis was 3.9% in 1980 and 5.6% in 1995. The relative risk for asthma (odds ratio [OR]: 1.7, 95% confidence interval [CI]: 1.3 to 2.3 in 1980; and OR: 1.7, 95% CI: 1.4 to 2.2 in 1995) and for chronic bronchitis (OR: 2.2, 95% CI: 1.5 to 3.2 in 1980; and OR: 1.9, 95% CI: 1.4 to 2.6 in 1995) among hairdressers was almost twice that in the reference group. The incidence rate of asthma in 1980 through 1995 was 2.2 and of chronic bronchitis was 1.1 cases per 1000 person-years among hairdressers, whereas the rate in the reference group was 1.3 asthma cases and 0.9 chronic bronchitis cases per 1000 person-years. The relative risk for developing asthma during the 15 years observation time was 1.7 (95% CI: 1.1 to 2.5) and for chronic bronchitis was 1.2 (95% CI: 0.7 to 1.9) among hairdressers, compared with referents. Our results indicate that hairdressers are at higher risk for developing asthma.

Adult↗
PubMed1997

Self reported respiratory symptoms and diseases among hairdressers.

OBJECTIVES: Hairdressers are exposed to many irritative and allergenic substances capable of causing occupational respiratory symptoms and diseases. The self reported prevalence of respiratory symptoms and diseases was studied, and the risks among hairdressers compared with saleswomen was estimated. METHODS: A cross sectional prevalence study of respiratory symptoms and diseases was carried out among hairdressers and supermarket saleswomen, with a computer assisted telephone interview method (CATI). The study population comprised all the female hairdressers and supermarket saleswomen aged 15-54 years in the Helsinki metropolitan area, Finland. Disproportionate random samples of female hairdressers and sales-women were drawn from the trade union membership registers. The interviews were carried out between February and April 1994. A response rate of 80.5% (355/440) was obtained for hairdressers and 82.2% (583/709) for saleswomen. Atopy, smoking, chronic illnesses, type of work, working hours, working conditions, personal and professional use of hair products, and the use of personal protective devices were assessed. The outcome variables were self reported symptoms of the upper and lower respiratory tract. These were used to define chronic bronchitis, and asthma, laryngitis, and allergic rhinitis diagnosed by a physician. RESULTS: There was a considerable difference in the prevalence of chronic bronchitis; 6.8% in hairdressers versus 1.9% in saleswomen. The odds ratio (OR) adjusted for age, smoking, and atopy for chronic bronchitis indicated an increased risk of chronic bronchitis (OR 4.8, 95% confidence interval (95% CI) 2.2 to 10.1). No association was found between work as a hairdresser and asthma, laryngitis, and allergic rhinitis. Also the prevalence of rhinitis, rhinitis with eye symptoms, cough with phlegm, dyspnoea, and dyspnoea accompanied by cough was increased among hairdressers. The corresponding adjusted risk ORs were 1.7 (95% CI 1.3 to 2.3) for rhinitis, 1.9 (95% CI 1.4 to 2.6) for rhinitis with eye symptoms, 1.4 (CI 1.1 to 1.9) for cough with phlegm, 1.5 (95% CI 1.0 to 2.2) for dyspnoea, and 1.6 (95% CI 1.0 to 2.7) for dyspnoea with cough. CONCLUSIONS: Our results indicate an increased prevalence of upper and lower respiratory symptoms among hairdressers. Allergenic and irritative chemicals in hairdressing are likely candidates explaining the difference found between the hairdressers and controls. Work related reasons should be considered when a hairdresser presents with airway symptoms. Preventive actions are needed to improve the working conditions and personal protection.

Adolescent↗
PubMed1997

Sensitization to industrial enzymes in enzyme research and production.

OBJECTIVES: This study investigated sensitization to industrial enzymes in Finnish enzyme production and in Finnish laboratories. METHODS: A cross-sectional study was conducted in 2 plants producing industrial enzymes and in their product development and research laboratories. Sensitization to enzymes and environmental allergens was examined by skin prick tests and specific immunoglobulin E determinations (radioallergosorbent test). The employees were interviewed for work-related respiratory symptoms. Altogether 173 employees were examined. RESULTS: The skin prick test showed 21 employees (12%) to be sensitized to one or more enzymes. Sixteen positive persons also had specific immunoglobulin E. Atopy was distinctly associated with enzyme sensitization. An exposure-response relationship was found for enzyme sensitization and for respiratory symptoms during work. For sensitization, the exposure-response linear trend was statistically significant. It weakened but remained statistically significant after stratification for atopy. For symptoms, likewise, the exposure-response linear trend was statistically significant, and the statistical significance remained after stratification for atopy. CONCLUSION: The study confirmed that industrial enzymes are potent sensitizers. The handling of dry enzymes in laboratory work may cause sensitization. Sensitization may even follow minute degrees of exposure, such as among office personnel. Atopics are more susceptible to sensitization than nonatopics. Nonatopics are also clearly at risk; the demonstrated exposure-response relationship emphasizes the need for and advantages of proper exposure control.

Adult↗
PubMed1997

Respiratory symptoms, pulmonary function and allergy to fur animals among fur farmers and fur garment workers.

OBJECTIVES: This study determined the prevalence of respiratory symptoms and immediate hypersensitivity to fur allergens among fur farmers and fur garment workers and measured the pulmonary function of these groups of workers. METHODS: Fur farmers (N=188) and fur garment workers (N=175) were compared with workers in a factory producing polyvinyl products (N=181) and bank and health center workers (N=118), respectively. The groups were given a self-administered questionnaire, lung function tests (spirometry, diffusing capacity), and skin prick tests to common environmental allergens, and epithelium (hair) and urine of fur animals. RESULTS: Rhinitis symptoms and eye complaints were significantly more common among the fur garment workers than among their referents, but were not associated with atopy. Between the fur farmers and their referents, the symptom prevalence did not differ significantly. Smoking explained the lower forced vital capacity and forced expiratory volume in 1 second of the fur garment workers. The prevalence of positive skin tests did not differ significantly between the exposed group and their respective referents. The skin tests showed cross-reactivity between antibodies to fur and domestic animal allergens. As confirmed by a questionnaire sent to former fur workers, selection took place for both groups of fur workers. CONCLUSIONS: Fur garment workers have an excess of rhinitis and eye symptoms, which primarily appear to be nonimmunologic. Allergy to fur animals forces sensitized workers, especially asthmatics, to leave the trade. A supplementary questionnaire to former workers on pertinent exposures and reasons for leaving a particular job can be recommended for use in prevalence studies.

Adolescent↗
PubMed1997

Allergic alveolitis following exposure to epoxy polyester powder paint containing low amounts (<1%) of acid anhydrides.

Only one case report concerning allergic alveolitis caused by polyester powder paint has been published previously. The aim of this study was to determine whether phthalic anhydride (PA) or trimellitic anhydride (TMA) is the alveolitis-causing agent in such paint. A 61 year old woman showed recurrent symptoms of chills, cough, and fever whilst at work. She was working in a plant where epoxy polyester powder paints were used to paint metal. The paint was found to contain low (<1%) amounts of TMA and PA. The patient showed shadowing on chest radiographs. In bronchoalveolar lavage, lymphocytosis (67%) and a low T-helper/T-suppressor ratio (0.2) were found. Transfer factor was within normal limits, but a slight reduction was verified after re-exposure to the paint. The symptoms, exposure, reduction in transfer factor, findings on chest radiographs and bronchoalveolar lavage were consistent with allergic alveolitis. In conclusion, the polyester powder paint used in the plant caused allergic alve olitis in this patient. Of the constituents in the paint, trimellitic anhydride and phthalic anhydride were the possible causative agents.

Air Pollutants, Occupational↗
PubMed1997

IgE response to fur animal allergens and domestic animal allergens in fur farmers and fur garment workers.

OBJECTIVE: The aim of this study was to compare the IgE response to the most commonly farmed fur animals with that to domestic animals. METHODS: IgE-immunoblotting and RAST-inhibition analyses were performed using RAST-positive sera from fur workers sensitized to fur allergens and sera from patients sensitized to domestic animal allergens. RESULTS: The urine extracts of mink, blue fox, silver fox, raccoon dog and fitchew contained more protein bands than the fur extracts did. Allergens with the same molecular weight were found in all of the fur and urine extracts. The most prominent allergenic bands had molecular weights of 62-67 kDa, 23-25 kDa and 18-19 kDa. With crossreacting sera the reciprocal RAST inhibition with all five animal extracts indicated common IgE-binding epitopes, probably common allergens (especially the 62-67 kDa bands). Urine and fur contain common allergens, since urine allergens strongly inhibited the IgE-binding to fur allergens. The IgE binding to allergenic bands of fur animal extracts was also observed in immunoblotting when dog and cat RAST-positive sera were used, but not for cow RAST-positive sera. RAST inhibition of dog-positive sera with fur animal extracts and fur-positive sera with dog extract confirmed the crossreactivity of these IgE antibodies. No such inhibition was seen with cow extract. CONCLUSION: The results of the RAST inhibition and immunoblotting suggest that fur animals have IgE binding epitopes or allergens in common with cat and dog--possibly albumin--but not with cow.

Agricultural Workers' Diseases↗
PubMed1997

Occupational asthma caused by triglycidyl isocyanurate (TGIC).

BACKGROUND: Polyester powder paints are extensively used in metal painting. Triglycidyl isocyanurate (TGIC), an epoxy compound, is often used as a hardener. Several cases of allergic eczema from occupational exposure to TGIC have been reported in the literature. OBJECTIVE: We examined a 36-year-old non-smoking man who worked mainly as a spray painter, using a polyester powder paint containing 4% TGIC. During painting he used protective clothing and a motorized breathing protector. After 4 years he developed eczema on his hands, face and body, and an occupational allergic eczema caused by TGIC was diagnosed. He also suffered from powder-paint-related asthmatic symptoms. METHODS: Occupational asthma was diagnosed in accordance with the accepted guidelines. Inhalation challenge tests were performed with the paint and TGIC. RESULTS: Spirometry showed slight obstruction; the blood eosinophils and serum IgE value were elevated. Skin-prick tests with common environmental allergens were negative. The challenge test with lactose powder was also negative. A challenge test with a paint containing TGIC (4%) induced a dual reaction in PEF and a late 23% fall in FEV1. A test with TGIC (4%) mixed with lactose induced a dual PEF reaction, and also dual changes in spirometry. The PD15 in the histamine challenge test decreased significantly after the challenge tests. CONCLUSIONS: To our knowledge this is the first diagnosed case of occupational asthma caused by TGIC. This case report emphasizes the importance of protecting both the skin and respiratory tract of workers against chemicals such as TGIC, capable of causing skin and respiratory allergy.

Adult↗
PubMed1996

Pocket-sized spirometer for monitoring bronchial challenge procedures.

Diagnosis of occupational asthma is verified by inhalation challenge testing when frequent monitoring of peak expiratory flow (PEF) or forced expiratory volume in 1 s (FEV1) is needed. FEV1 measurements also allow frequent monitoring of changes in small airways. For the follow-up of lung function of suspected occupational asthma, a reliable, personal and mobile device is needed. We studied the accuracy of a pocket-sized spirometer, Micro Plus Spirometer (MP), compared with our former combination of two devices, i.e. the values of forced expiratory volume in 1 s (FEV1) with those measured with the Vitalograph bellow spirometer (V); and the peak expiratory flow (PEF) values with the values obtained with a Wright PEF meter (W). In healthy control subjects, the values of FEV1 obtained with Micro Plus correspond well to those obtained using a bellow spirometer (R = 0.97) and the mean difference (MP-V) was -0.06 1 irrespective of the mean FEV1 value. W gives smaller PEF values than the MP; the mean difference in PEF (MP-W) was 44 1 min-1, but the values increased linearly with increasing flow. The poor relation between PEF values might be based on the low reliability of the Wright device. In patient follow-up, the FEV1 values measured with MP and V showed a good correlation (R = 0.99). The PEF values in patients increase linearly measured with W vs. MP with increasing flow values. In conclusion, we found the pocket-sized spirometer a handy and useful device for monitoring bronchial challenge procedures in patients with suspected occupational asthma. The number of exhalations during the challenge test follow-up is lessened when FEV1 and peak expiratory flow (PEF) can be measured simultaneously.

Adult↗
PubMed1996

Enzyme exposure and enzyme sensitisation in the baking industry.

OBJECTIVES: To assess the exposure to enzymes and prevalence of enzyme sensitisation in the baking industry. METHODS: A cross sectional study was conducted in four bakeries, one flour mill, and one crispbread factory. Sensitisation to enzymes, flours, and storage mites was examined by skin prick and radioallergosorbent (RAST) tests. 365 workers were tested. The workers were interviewed for work related respiratory and skin symptoms. Total dust concentrations were measured by a gravimetric method, and the concentration of alpha-amylase in air was measured by a catalytic method. An immunochemical method was used for measuring cellulase and xylanase in air. RESULTS: Total measured dust concentrations were from 0.1 to 18 mg/m3, with highest values in dough making areas of bakeries. The alpha-amylase concentrations generally followed the total dust concentrations and reached the highest values < 6.6 micrograms/m3 in the same areas. Cellulase and xylanase varied with concentrations < 180 ng/m3 and < 40 ng/m3, respectively, in the flour mill and the crispbread factory. No cellulase, but concentrations of 1-200 ng/m3 xylanase, were found in the bakeries, probably indicating the natural xylanase activity of wheat. 12 workers (8%) in the bakeries, three (5%) in the flour mill, and four (3%) in the crispbread factory were skin prick positive to enzymes. The corresponding percentages of positive reactions to flours were 12%, 5%, and 8%. CONCLUSIONS: The study confirmed that industrial enzymes in baking used as additives in a powdered form pose a risk of sensitisation. The no effect air concentrations for industrial enzymes are not known. Based on present knowledge, however, lowering exposures and eliminating short and high peaks by technical measures would lower the risk of sensitisation. This would be most effectively accomplished by shifting to non-dusty products.

Adult↗
PubMed1996

Occupational asthma: measures of frequency from four countries.

Disease registers and surveillance schemes are not necessarily designed to measure incidence and prevalence, but their data can provide useful epidemiological insights. Their main functions are the detection and identification of hazards so that further cases can be prevented, and to provide a database for research to improve our understanding of the determinants and consequences of disease. Occupational asthma probably accounts for only a small proportion of adult asthma, of the order of 2-6% in the UK. On the other hand, asthma is very common and so thousands of people in the UK and in other western countries have asthma as a result of their work. The frequency of the disease in less developed countries is unknown but is potentially very large. Information on incidence is patchy but from Finland, where ascertainment is most complete, there are approximately 140 per million working people affected each year, and even there disease in the self-employed is probably missed. Data for the UK are limited to cases seen by specialist physicians and the best estimate is that the annual incidence of such cases is about 50 per million. Through internal comparisons and analysis it is possible to judge the extent to which variation in ascertainment and reporting have affected the frequency of reported disease, but so far it has not been possible to measure the underestimation due to persons with work-related symptoms not seeking medical attention or not being referred to a specialist.

Adolescent↗
PubMed1996

A thirteen-year follow-up of respiratory effects of acute exposure to sulfur dioxide.

OBJECTIVES: In 1977, nine men were accidentally exposed to sulfur dioxide in an explosion in a pyrite mine. The lung function of seven men was followed after the accident. A four-year follow-up has been published previously. The greatest decrease in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), and maximal midexpiratory flow (MMEF) was observed one week after the accident, after which all these parameters improved without reaching the preaccident level. Reversible bronchial obstruction was still present in three patients, and a positive reaction in the histamine challenge test was found for four. In the present paper, the lung function follow-up 13 years after the accident is reported for six men. METHODS: The patients' clinical condition, chest X-ray, spirometry, and histamine challenge test were studied 13 years after the incident. RESULTS: Spirometry was normal in one worker, two displayed obstruction, and three had a combined obstructive and restrictive, mainly obstructive, ventilatory impairment. In the histamine challenge test, four patients showed bronchial hyperreactivity, one with a nearly significant reaction. Because of bronchial obstruction one patient could not perform the challenge test. CONCLUSIONS: This 13-year follow-up showed that acute inflammatory obstruction caused by exposure to sulfur dioxide left, as sequelae, obstructive impairment of ventilatory function and permanent bronchial hyperreactivity. The clinical picture displayed by these patients was named the "reactive airways dysfunction syndrome" (RADS) in 1985. Four of the patients also showed symptoms of chronic bronchitis.

Acute Disease↗