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PubMed2005

Use of surrogate markers of biological agents in air and settled dust samples to evaluate a water-damaged hospital.

UNLABELLED: An environmental survey was conducted in two hospital buildings in Montana, one of which had historical water incursion on the top floors and higher prevalence of reported respiratory symptoms that improved when the occupants were away from work. We measured culturable fungi and bacteria, fungal spores, endotoxin, and sub-micron particles in air; and culturable fungi and bacteria, endotoxin, markers of fungi (extra-cellular polysaccharides specific for Penicillium/Aspergillus, ergosterol, and beta(1-->3) glucans) and cat allergen in chair and floor dusts. For the analytes measured in air, the correlation coefficients ranged from 0.43 to 0.78 (P < 0.05). In chair dust, beta(1-->3) glucan concentrations correlated with culturable fungi and ergosterol concentrations. We found that sub-micron particles and markers of microbiological agents, but not culturable microbiological agents, were significantly positively associated with the building that had both historical water damage and higher prevalence of reported respiratory symptoms. Chair dust measurements tended to be higher in the non-complaint building. These results suggest that air and floor dust measurements of marker compounds may be better indicators of current health risk in a water-damaged environment than chair dust measurements or measurements of culturable fungi or bacteria in air or settled dust. PRACTICAL IMPLICATIONS: Detection and quantification of nonculture-based microbiological markers and/or agents of disease may be useful methods to assess microbial contamination and to more accurately evaluate microbial exposures in the indoor environment for exposure-response studies.

Air Microbiology↗
PubMed2005

Allergens and endotoxin in settled dust from day-care centers and schools in Oslo, Norway.

UNLABELLED: Allergy to indoor allergens can cause frequent and severe health problems in children. Because little is known about the content of allergens in the indoor environments in Norway, we wanted to assess the levels of cat, dog and mite allergens in schools and day-care centers in Oslo. Allergen levels in dust samples from 155 classrooms and 81 day-care units were measured using commercially available enzyme-linked immunosorbent assay (ELISA) kits. Additionally, we measured the levels of endotoxin in 31 day-care units, using the limulus amebocyte lysate test. Most of the dust samples contained detectable amounts of cat and dog allergens. In mattress and floor dust (day-care centers), and curtain and floor dust (schools) the median Fel d 1 levels were 0.17, 0.002, 0.02 and 0.079 microg/m2, while the median Can f 1 levels were 1.7, 0.03, 0.1 and 0.69 microg/m2, respectively. Levels of cat and dog allergens in school floor dust were associated with the number of pupils with animals at home. In contrast, <1% of the samples had measurable levels of the mite allergen Der p 1. Moreover, the levels of endotoxin tended to be higher in dust from floors (1.4 ng/m2) compared with that from mattresses (0.9 ng/m2). PRACTICAL IMPLICATIONS: To reduce allergen exposure, allergic individuals should be placed in the classes/rooms with the fewest pet owners. Moreover, mattresses in day-care centers are major reservoirs of cat and dog allergens and should be cleaned frequently.

Air Pollution, Indoor↗
PubMed2006

Fungal and endotoxin measurements in dust associated with respiratory symptoms in a water-damaged office building.

UNLABELLED: We investigated the associations of fungal and endotoxin levels in office dust with respiratory health in 888 (67% participation) occupants of a water-damaged building. We analyzed floor and chair dusts from 338 workstations for culturable fungi and endotoxin. Based on averages, we ranked each floor of the building as low, medium, or high for occupants' exposure to each of these agents. Multivariate logistic regression models for building-related symptoms included this ranking of fungi and endotoxin, age, gender, race, smoking status, and duration of occupancy. Using floor dust measures, we found significantly increased odds for lower respiratory symptoms [wheeze, chest tightness, attacks of shortness of breath, and attacks of cough: odds ratios (OR) = 1.7 (95% confidence interval (CI): 1.02-2.77) to 2.4 (95% CI: 1.29-4.59)], throat irritation [OR = 1.7, (95% CI: 1.06-2.82)], and rash/itchy skin [OR = 3.0, (95% CI: 1.47-6.19)] in the highest fungal exposure group compared to the lowest, with generally linear exposure-response relationships. Nonlinear relationships were observed for many of these symptoms and endotoxin in floor dust. Interaction models showed that endotoxin modified effects of fungi on respiratory symptoms. Our findings of exposure interactions and exposure-response relationships of fungal and endotoxin with increased risk of building-related symptoms contribute to an understanding of the role of microbial agents in building-related asthma and respiratory and systemic symptoms. PRACTICAL IMPLICATIONS: Our demonstration of exposure-response relationships between measurements of fungi and/or endotoxin in floor dusts and building-related symptoms implies that microbial agents in floor dust may be a good surrogate measure for dampness-related bioaerosol exposure, considering that measurements of microbial agents in air often fail to demonstrate the associations between exposure and health. In addition, our finding that endotoxin exposure may change the effect of fungal exposure (and vice versa) on respiratory heath suggests that exposure to both fungi and endotoxin should be assessed in epidemiological investigations examining the effect of fungal or endotoxin exposure on respiratory health in indoor environments.

Air Pollution, Indoor↗
PubMed1983

The action of dust in the airways on secretion into the trachea of the cat.

The effects of inert dusts administered into cat airways on the release of radiolabelled mucus glycoproteins (mucins) from an isolated tracheal segment have been investigated. Charcoal dust or barium sulphate powder, when placed in the segment, stimulated release of both 35S- and 3H-labelled mucins. The effect of dust was not significantly reduced after denervation of the segment. Charcoal dust, when added to the inspired air, caused an increase in release of mucins labelled with both radio-isotopes. Bilateral vagotomy significantly reduced this effect, but atropine and l-propranolol administered together did not. It is concluded that inert dust can stimulate tracheal mucin output both by a local mechanism and by activation of a reflex. The types of receptor that may be involved in the reflex, and the possible role of the mucotropic effects of dust in airway clearance, are discussed.

Animals↗
PubMed1974

Effects of carbon dust inhalation on the cell-mediated immune response in mice.

The effects of carbon dust inhalation on the bone marrow-derived (B) and thymus-derived (T) lymphocyte populations of spleen and mediastinal lymph node (MLN) cultures were examined. The concanavalin A (Con A)-responsive cell population (T cells) in the spleen was found to be depressed after 7 days of pre-exposure to carbon dust. However, this effect was transient, and after 14, 21, and 28 days of pre-exposure to carbon dust, the Con A-responsive cells exhibited a 30 to 40% enhancement over control group responses. Conversely, Con A-responsive cells in the pooled MLN cultures exhibited depression, ranging from 22 to 33% below control group values, after 7, 14, and 28 days of pre-exposure to carbon dust. The lipopolysaccharide (LPS)-responsive cell population (B cells) in the spleens of carbon-exposed mice was found not to differ significantly from control group values after all times of pre-exposure. LPS-responsive cells in the MLN cultures exhibited enhancement, ranging from 49 to 74% above control values, after 14, 21, and 28 days of pre-exposure to carbon dust. The ability of carbon spleen cell cultures from carbon-exposed mice to undergo antigen induced blast transformation after sensitization with Mycobacterium tuberculosis H37Ra was also determined. Mice exposed to carbon dust inhalation 2 weeks before and 3 weeks after aerosol or subcutaneous immunization exhibited significantly enhanced ratios of transformation upon culture of their spleen lymphocytes with purified protein derivative of tuberculin.

Aerosols↗
PubMed2004

Dust concentrations and respiratory risks in coalminers: key risk estimates from the British Pneumoconiosis Field Research.

To help inform the setting of dust control standards in coalmines, this brief review summarises the most recent and reliable exposure-response relations, for damaging respiratory effects, derived from the Pneumoconiosis Field Research (PFR). Collecting data over 38 years in the British coal industry, this was a programme of prospective research on the respiratory health of coal miners, characterised by regular health surveys and detailed measurements of dust and silica concentrations in the workplace. Exposure-response relations are presented for coal workers' simple pneumoconiosis category II, progressive massive fibrosis, defined deficits of lung function (FEV1), and category II silicosis. This simplified overview provides a guide to the most recent and most reliable estimates from the PFR of dust-related risks of substantial pulmonary disease, and to the magnitude of the effects. Control of dust sufficient to prevent category II simple pneumoconiosis should prevent most cases of progressive massive fibrosis and most dust related large lung function deficits. Where the dust contains high proportions of silica, control to low levels is essential, and even quite brief excursions of silica to high levels must be avoided.

Adult↗
PubMed1987

Exposure to respirable coalmine dust and incidence of progressive massive fibrosis.

Data gathered since 1953 concerning more than 30,000 coalminers while employed at 24 collieries in England, Scotland, and Wales have been used to study the incidence of progressive massive fibrosis (PMF) in working coalminers. Results refer to 52,264 approximately five year intervals when the miners were at risk of an attack of PMF. One objective of the present study was to describe how the five year attack rate of PMF was related to miners' age, colliery, and simple pneumoconiosis category at the start of the periods at risk. The main objective was to estimate the relation between exposure to dust and incidence of PMF and to examine how this relation changes in the presence of coalworkers' simple pneumoconiosis (CWSP). Film readings, in some cases based on clinical assessments only, showed 462 attacks of PMF over the five year risk periods. The men concerned had experienced higher cumulative exposures to dust than their colleagues of similar age at the same collieries, a result found at 65 of the 68 age colliery groups where an attack had occurred. The association was highly significant statistically. Simple pneumoconiosis clearly predisposed to PMF, with five year attack rates of 13.9%, 12.5%, 4.4%, and 0.2% among men with categories 3, 2, 1, and 0 respectively at the start of the risk periods. Once simple pneumoconiosis category 1 or more had been attained, those with higher cumulative exposure to dust were not at greater risk of an attack of PMF than other men with the same CWSP category. Among most miners, those with category 0, however, the risks of an attack of PMF increased clearly with exposure. Risks of an attack were higher among older men irrespective of CWSP category. In addition, there were large colliery specific variations in incidence related to variations in the carbon content of the coal though not fully explained by them. It is concluded that cumulative exposure to respirable dust is the decisive central factor in the development of PMF. Its effect is primarily in causing simple pneumoconiosis category 1 or higher which predisposes to PMF, though the dust related incidence among men with category 0 is not negligible in view of the large numbers at risk. Continuation of the policy to minimise dust concentrations underground therefore seems the only secure strategy to limit, and eventually eliminate, PMF.

Adult↗
PubMed1993

Longitudinal and cross sectional analyses of exposure to coal mine dust and pulmonary function in new miners.

The association between exposure to dust and pulmonary function was studied by longitudinal and cross sectional analyses in a group of United States underground coal miners beginning work in or after 1970. Quantitative estimates of exposure to respirable coal mine dust were derived from air samples taken periodically over the entire study period. The cohort included 977 miners examined both in round 2 (R2) (1972-5) and round 4 (R4) (1985-8) of the National Study of Coal Workers' Pneumoconiosis. Multiple linear regression models were developed for both cross sectional (pulmonary function at R2 and R4) and longitudinal (change in pulmonary function between R2 and R4) analyses with exposure partitioned into pre-R2 and post-R2 periods and controlled for covariates including smoking history. The results indicate a rapid initial (at R2) loss of FVC and FEV1 in association with cumulative exposure of the order of 30 ml per mg/m3-years. Between R2 and R4 (about 13 years) no additional loss of function related to dust exposure was detected although the percentage of predicted FVC and FEV1 did decline over the period. After some 15 years since first exposure (at R4), a statistically significant association of cumulative exposure with FEV1 of about -5.9 ml per mg/m3-years was found. These results indicate a significant non-linear effect of exposure to dust on pulmonary function at dust concentrations present after regulations took effect. The initial responses in both the FVC and FEV1 are consistent with inflammation of the small airways in response to exposure to dust.

Adult↗
PubMed1994

Emphysema and airway obstruction in non-smoking South African gold miners with long exposure to silica dust.

OBJECTIVE: Occupational exposure to silica dust is associated with significant impairment of lung function. The present study investigates which pathological changes in the lung are associated with impairment of lung function in silica dust exposed workers who were life-long non-smokers. METHODS: 242 South African white gold miners who were lifelong non-smokers and who had a necropsy at death were studied. The pathological features identified at necropsy were the degree and type of emphysema, the presence of airway disease, and the degree of silicosis in the lung parenchyma and pleura. These features were related to lung function tests done a few years before death, to type of impairment (obstructive or restrictive), and to cumulative silica dust exposure. RESULTS: The degree of emphysema found at necropsy was not associated with a statistically significant impairment of lung function or with dust exposure. The degree of silicosis in the lung parenchyma and the large airways disease (based on mucus gland hyperplasia) were associated with a statistically significant impairment of lung function. The large airway disease was, however, not positively associated with dust exposure or silicosis. In miners with a moderate or a higher degree of limitation of airflow the main findings were silicosis, heart disease, and obesity. The presence of small airways disease could not be established from the necropsy material. CONCLUSION: The results indicate that the level of exposure to silica dust to which these miners were exposed, without a confounding effect of tobacco smoking, is not associated with a degree of emphysema that would cause a statistically significant impairment of lung function. Silicosis of the lung parenchyma was associated with loss of lung function. Other factors that may play a part in impairment of lung function in these miners are obesity and heart disease.

Adult↗
PubMed1995

New method for an occupational dust challenge test.

OBJECTIVES: Specific challenge tests with a suspected allergen in the workplace are standard to confirm the diagnosis of asthma. Facilities for sophisticated exposure tests are available only in a few institutions. A pilot study was carried out that used a novel approach for an occupational dust challenge test with a rotahaler. METHODS: Nine consecutive patients were enrolled in this study. Six of these proved to have asthma to red cedar by challenge tests with plicatic acid. They were challenged with a maximum dosage of 80 mg of red cedar dust and spruce dust (control) with a rotahaler on separate days in a single blinded manner. A positive reaction was defined as a fall in the forced expiratory volume in one second (FEV1) or the peak expiratory flow (PEF) after a challenge test of > or = 20% below the baseline value. RESULTS: Three of the six patients who reacted to plicatic acid also had a positive response to red cedar dust delivered through a rotahaler. All three patients with a negative response to challenge with plicatic acid also showed a negative response to red cedar dust. CONCLUSIONS: This pilot study showed that a positive challenge test with a rotahaler to deliver red cedar dust was specific in the diagnosis of red cedar asthma but a negative response could not rule out the diagnosis. The rotahaler has merits of being easy to operate, safe, inexpensive, and readily available. The usefulness of this method and its reproducibility have to be examined in a series of patients.

Adult↗
PubMed2000

Symptoms, airway responsiveness, and exposure to dust in beech and oak wood workers.

OBJECTIVES: To investigate the relation between levels of cumulative exposure to wood dust and respiratory symptoms and the occurrence of bronchial hyperresponsiveness among beech and oak workers. METHODS: 114 Male woodworkers from five furniture factories and 13 male unexposed controls were examined. The unexposed control group was supplemented by 200 male historical controls. Statistical analyses were performed excluding and including the historical controls. Dust concentration was measured by personal sampling methods. Cumulative exposure to dust was calculated for each woodworker by multiplying the duration of the work by the intensity of exposure (years. mg/m(3)). Bronchial hyperresponsiveness was assessed by the methacholine bronchial challenge test. Subjects were labelled methacholine bronchial challenge positive if forced expiratory volume in 1 second (FEV(1)) fell by >/=20%. The linear dose-response slope was calculated as the last dose divided by the total dose given. RESULTS: 443 Dust samples were collected. The median cumulative exposure to dust was 110 years.mg/m(3) with lower and upper quartiles at 70 and 160 years.mg/m(3) Overall, no declines in FEV(1) and forced vital capacity (FVC) were found with increasing exposures. A dose-response relation was found between intensity of exposure on the one hand, and sore throat, increased prevalence of positive methacholine bronchial challenge tests, and steeper dose-response slope, on the other. CONCLUSION: Exposure to oak and beech dust may lead to the development of sore throat and bronchial hyperresponsiveness.

Adult↗
PubMed1988

Effect of house dust mite avoidance measures on adult atopic asthma.

Twenty one adult patients with asthma, with positive skin test responses to the European house dust mite, Dermatophagoides pteronyssinus, were randomly allocated to a control group or to a group applying house dust mite avoidance measures. These included an initial application of liquid nitrogen to mattresses and bedroom carpets to kill the live house dust mite population. Histamine airway responsiveness, symptom scores, peak expiratory flow rates (PEF), and house dust mite numbers were determined during the two week pretrial and eight week trial periods. Nine patients in each group completed the study. By the end of the study there was a significant reduction in live mites in the "avoidance" group but not in the control group. The avoidance group showed a significant improvement in symptom scores measured on a linear analogue scale, in the number of hours each day spent wheezing (mean reduced from 8.6 to 4.5 hours), and in PEF (l/min) both in the morning (from 364 to 388) and in the evening (from 368 to 392). These changes were not found in the control group. The provocative concentration (PC) of histamine causing a 20% fall in FEV1 (PC20FEV1) had increased significantly in the avoidance group at eight weeks (from 0.58 to 2.3 mg/ml), whereas no change was seen in the control group (from 0.93 to 1.21 mg/ml). These results show that house dust mite avoidance, combined with initial killing of the mite by liquid nitrogen, diminishes airway responsiveness and improves asthma symptom control over an eight week period in adult asthmatic patients with house dust mite allergy.

Adolescent↗
PubMed1991

Silicosis in a Himalayan village population: role of environmental dust.

The Himalayan villages of Chuchot Shamma and Stok were surveyed because silicosis had been suspected from the radiographs of some of the inhabitants. The villages are agricultural, and Chuchot is exposed to frequent dust storms. Chest radiographs of villagers aged 50-62 were assessed blind by two independent observers using ILO criteria. In Chuchot five of seven men and all of the nine women examined showed varying grades of silicosis, compared with three of 13 men and seven of 11 women in Stok, which lies 300 metres higher and is exposed to fewer dust storms. The difference in prevalence of silicosis between the two villages was significant, as was the differences between men and women. Three patients from the village adjoining Chuchot were later found to have radiological evidence of progressive massive fibrosis. A necropsy on a man in a neighbouring village in the Indus valley showed classical silicosis in a hilar lymph node. Chemical analysis of the inorganic dust in the lung showed that 54.4% was elemental silicon [corrected]. This was similar to the silicon [corrected] content of dust samples collected from houses in Chuchot, which included particles of respirable size. X-ray microanalysis showed that quartz formed 16-21% of the inorganic lung dust. This study suggests that silicosis is common among the older inhabitants of these Himalayan villages. The dust exposure is clearly environmental and not industrial. Further studies are needed to define the extent and severity of silicosis in this community and to examine possible preventive measures.

Dust↗
PubMed1993

Additive effects of exposure to silica dust and smoking on pulmonary epithelial permeability: a radioaerosol study with technetium-99m labelled DTPA.

BACKGROUND: Increased pulmonary epithelial permeability evaluated by the rate of clearance from lung to blood of the radioaerosol solute technetium-99m labelled diethylenetriamine pentaacetate (99mTc-DTPA) has been reported in smokers and in workers exposed to silica dust. A study was carried out to determine whether there are additive effects of cigarette smoke and exposure to silica dust on clearance rates of 99mTc-DTPA in ceramic workers. METHODS: Thirty one subjects with silicosis were studied, of whom 18 smoked cigarettes and 13 were non-smokers. They had similar histories of exposure to silica dust, and radiological alterations consistent with silicosis. The results from these patients were compared with those from normal subjects and smokers previously studied by the authors. RESULTS: Pulmonary function values were normal in most patients and not significantly different among groups. The median (range) rate of clearance of 99mTc-DTPA in smokers with silicosis was 4.1 (1.9-12.7) %/minute, which was higher than the rates in non-smoking patients with silicosis of 2.2 (1.1-6.6) %/minute and in smokers without exposure to silica dust of 2.9 (1.6-4.5) %/minute. These differences were more evident and significant when the clearance rates of the lower lobes of the three groups were compared. Clearance rates higher than 3%/minute were much more frequent in smokers with silicosis (85%) than in non-smoking patients with silicosis (15%) and in smokers (40%). CONCLUSION: In ceramic workers with radiographic changes resulting from exposure to silica dust, there is an additive effect of inhalation of silica dust and cigarette smoking on clearance rates of 99mTc-DTPA.

Adult↗
PubMed1997

Effect of exposure to swine dust on levels of IL-8 in airway lavage fluid.

BACKGROUND: Inhalation of swine dust causes airway inflammation with influx of inflammatory cells, predominantly neutrophils, into the lungs. A study was undertaken to determine whether or not exposure to swine dust induces release of interleukin 8 (IL-8) into upper and lower airways and how this possible release is related to cellular influx. A further aim was to study the relationship between the inflammatory response and swine dust exposure. METHODS: Thirty one healthy, non-smoking, previously unexposed subjects were exposed to swine dust during three hours work in a swine house. Bronchoalveolar lavage (BAL) was performed two weeks before and 24 hours after the exposure (n = 16). Nasal lavage and acoustic rhinometry were carried out 1-2 hours before and seven hours after the start of the exposure (n = 31). Exposure measurements were performed with personal sampling equipment. RESULTS: The exposure led to 19-fold and 70-fold increases in the neutrophil concentrations in nasal lavage and BAL fluid, respectively (p < 0.001). In BAL, fluid macrophages, lymphocytes and eosinophils increased significantly. The IL-8 levels in BAL fluid increased from < 31.3 ng/l to 63 (43-109) ng/l (median (25-75th percentile), p < 0.001), and in nasal lavage fluid the concentrations increased from 144 (97-227) ng/l to 1064 (864-1437) ng/l (p < 0.001). IL-8 levels showed a significant correlation with the increase in neutrophils in the nasal lavage fluid but not in the BAL fluid. Acoustic rhinometry demonstrated significant swelling of the nasal mucosa. The air concentration of inhalable dust was 23.3 (20.0-29.3) mg/m3, endotoxin 1.3 (1.1-1.4) micrograms/m3, and muramic acid 0.99 (0.78-2.1) microgram/m3. CONCLUSIONS: The concentration of IL-8 increases in BAL fluid and nasal lavage fluid following exposure to swine dust and may be one of the chemoattractants contributing to the recruitment of neutrophils to the nasal cavity and the alveolar space.

Adult↗
PubMed1991

Respiratory effects of occupational exposure to tobacco dust.

The ventilatory capacities of 195 tobacco factory workers exposed to tobacco dust and 190 Libyan men not exposed to tobacco dust were measured. In both groups, the forced vital capacity (FVC) and forced expiratory volume in 1 s were found to be correlated with age, stature, sitting height and body surface area. Those exposed to tobacco dust have decreased ventilatory capacity values as compared with age-matched unexposed workers. The duration of exposure to tobacco dust does not appear to have any significant effect on the ventilatory function. There was no significant difference in the lung function test values between the smokers and nonsmokers in both groups. The flow-volume curves were constructed for the unexposed and exposed groups of workers. At 25% FVC, in the group exposed to tobacco dust, there was a decrease in air flow by 20.8% as compared to age-matched normal unexposed Libyans. This indicates that the small airways are affected by exposure to tobacco dust. Flow-volume curves are useful in the assessment of lung function status.

Adult↗
PubMed1997

Cow hair allergen (Bos d 2) content in house dust: correlation with sensitization in farmers with cow hair asthma.

Farmers (N = 45) suffering from occupational cow hair asthma were visited at home to evaluate the concentration of cow hair major allergen Bos d 2 in the house dust and to correlate these results with measures of avoidance, degree of sensitization, clinical symptoms, and lung function. Bos d 2 was determined by rocket immunoelectrophoresis. In dust of tiles and linoleum Bos d 2 was difficult to detect, whereas dust samples of carpets often contained high concentrations of the allergen (50-520 micrograms/g fine dust). Bos d 2 levels were significantly higher when barn and living quarters were in the same building. Concentrations of cow hair-specific IgE were correlated with concentrations of Bos d 2 in house dust samples. A concentration of 20-29 micrograms Bos d 2 per gram of house dust could be established as threshold value for relevant IgE sensitization. Avoiding the barn is not a sufficient avoidance measure for cow hair asthmatics if the partner continues cattle farming. Cessation of cattle farming and avoiding the former barn results in a marked reduction in Bos d 2 concentration in living quarters, a decreased degree of sensitization, and a reduced symptom score. Farmers with cow hair asthma should avoid cattle and thoroughly clean all carpets in the living quarters to avoid continuous cow allergen exposure.

Adult↗
PubMed1994

Swine dust causes intense airways inflammation in healthy subjects.

Fourteen healthy, nonsmoking subjects were exposed to swine dust while weighing pigs for 3 to 5 h in a swine-confinement building. All but one participant was previously unexposed to swine dust. Bronchoalveolar lavage (BAL) was performed and blood samples were drawn before and after exposure. Total dust and endotoxins were measured by air sampling in filter cassettes carried in the breathing zone. The air concentration of endotoxins was 0.6 (range, 0.08 to 1.3) micrograms/m3, and of total dust was 13.5 (range, 5.6 to 24.0) mg/m3. The air concentrations of ammonia, carbon dioxide, and hydrogen sulfide were low. The exposure induced fever in three and malaise and drowsiness in six of the subjects. Compared with preexposure values, a 75-fold increase in neutrophilic granulocytes, a two- to threefold increase in mononuclear cells, and a significant increase in eosinophilic granulocytes were observed in the BAL fluid obtained 1 day (approximately 22 h) after exposure (p < 0.01 for all cell types). The fibronectin and albumin concentrations in the BAL fluid significantly increased (p < 0.01 for both). The number of leukocytes in peripheral blood was almost doubled 6 h after exposure and was still significantly elevated after 1 day. Blood concentrations of orosomucoid and C-reactive protein (CRP) were significantly increased 1 day after exposure. We conclude that exposure to swine dust in a swine-confinement building induces an intense inflammatory reaction in the airways as assessed by BAL. The airway cellular response is characterized by a dramatic increase in neutrophils. The components in the swine dust that cause the reaction are not clear.

Adult↗