Lungs Of Workers Research Articles

Tobacco Worker's Lung: A Neglected Subtype of Hypersensitivity Pneumonitis.

Tobacco worker's lung (TWL) is a type of hypersensitivity pneumonitis (HP) affecting workers exposed to tobacco leaves and molds in the humidified environment of the tobacco production industry. Limited epidemiological data point to a prevalence of TWL that is not negligible and probably underestimated. As in other types of HP, an acute vs. chronic presentation depends on the pattern of the exposure. Therefore, the clinical presentation can vary from an acute influenza-like syndrome, mostly self-limiting with the removal of the exposure, to an insidious onset of cough, exertional dyspnea, fatigue and weight loss in chronic presentations, where fibrotic changes may be observed. The main treatment strategy is the removal of the exposure to tobacco dust and molds, while the main aim of corticosteroid therapy is to reduce morbidity and prevent complications, namely the development of pulmonary fibrosis and permanent lung dysfunction. Despite the fact that TWL is quite well described, preventive measures are not usually adopted in the tobacco production industry. We present here a state of the art review of this neglected, preventable, but still prevalent and occupational-related subtype of HP.

Hypersensitivity Pneumonitis Caused by Oyster Mushrooms: A Case of Mushroom Worker's Lung

Hypersensitivity Pneumonitis Caused by Oyster Mushrooms: A Case of Mushroom Worker's Lung

Measuring the activity of inhaled ²²²Rn using a lung counting system.

A new method of directly measuring (222)Rn progeny in a worker's lung using a lung counting system is introduced. To determine the efficiency of the lung counting system, a torso phantom manufactured by the China Institute for Radiation Protection was used, where activated carbon that had been loaded in a radon chamber with a defined quantity of radon represented the lungs, which were usually made of urethane foam. The minimum detectable activity (MDA) of (214)Bi, one of the (222)Rn progenies, was estimated to be 7.3 Bq for a measurement time of 4000 s. Based on the time (222)Rn progenies stay in the lung, it may be concluded that the lung counting system described can be well used for directly measuring the activity of (214)Bi in the lung short time after a worker inhaled (222)Rn at his/her workplace.

Flock Worker's Lung Disease: Natural History of Cases and Exposed Workers in Kingston, Ontario

BackgroundThe natural history of flock worker's lung (FWL) and longitudinal lung function changes in nylon flock-exposed workers have not been well characterized. MethodsSymptoms, pulmonary function testing, and chest radiographs from five index cases, subsequent case referrals, and screened employees of a flocking plant in Kingston, Ontario, Canada, were compared and analyzed for changes over time (variable follow-up intervals between 1991 and 2011). ResultsNine cases and 30 flock-exposed workers without FWL were identified. Four cases had persistent interstitial lung disease despite three having left the workplace. Two developed hypoxemic respiratory failure and secondary pulmonary hypertension and died of complications 18 and 20 years after diagnosis, respectively. Five cases resolved after leaving the workplace. Compared with resolved cases, persistent cases had lower diffusing capacity of the lung for carbon monoxide at presentation (P < .05) and follow-up (P < .05). Among exposed workers employed for 14.5 ± 4.7 years, five had abnormal chest radiographs vs none at baseline (P = .001) over 14.8 ± 4.6 years of follow-up. The prevalence of wheeze increased (P = .001), and FEV1/FVC decreased (P < .001). FEV1 % predicted was significantly lower at follow-up (P = .05). Average FEV1 decline was 46 mL/year (range, −27 to 151 mL/y). Seventy-seven percent of exposed workers were current or former smokers. ConclusionsThe natural history of FWL includes the following patterns: complete resolution of symptoms; radiographic and pulmonary function abnormalities; permanent, but stable symptoms and restrictive pulmonary function deficits; and progressive decline in pulmonary function, causing death from respiratory failure and secondary pulmonary hypertension. A low baseline diffusing capacity of the lung for carbon monoxide is associated with the persistence and progression of FWL.

Occupational Hypersensitivity Pneumonitis Reported to the Czech National Registry of Occupational Diseases in the Period 1992-2005

Between 1992 and 2005, 72 cases of occupational hypersensitive pneumonitis were reported to the Czech National Registry of Occupational Diseases. This represented 0.24% of all occupational diseases reported in the Czech Republic during that period. The greatest number of cases occurred in 1997 (10 cases), of which men constituted 58.3% (42 cases) and women 41.7% (30 cases). The most prevalent cases were farmer's lung (50 cases), malt worker's lung (7 cases) and chemical worker's lung (6 cases). Agriculture was the most common economic activity (total 48 cases), with cattleman and dairyman (total 26 cases) the most frequent occupations; less common were tractor driver (8 cases) and maltster (7 cases). Typical case reports after different exposures are presented. A peak in frequency was observed in the age groups of 45-49 and 50-54 yr (20.8% and 19.4% of cases, respectively) and within the first four years of employment (22.2% of cases). Median age was 48 yr and median exposure 12.5 yr. Incidence was in the range of 0.00-0.20 per 100,000 workers, which appears rather low. Due to the difficult diagnostics of hypersensitive pneumonitis, the actual number of cases is undoubtedly higher, and this disease is probably under-reported.

Pneumopathie d’hypersensibilité chez une endivière

We report a case of occupational hypersensitivity pneumonitis in a patient handling chicory leaves. The diagnosis was based symptoms of broncho-alveolitis with pyrexia, positive precipitins to moulds present on chicory, especially Fusarium, and the disappearance of the clinical and radiological manifestations following cessation of exposure to chicory. "Chicory worker's lung" is an occupational disease which should be considered in cases of respiratory symptoms suggestive of hypersensitivity pneumonitis and chronic exposure to chicory leaves.

Passing the hot potato…or popcorn

You'd better think twice before cranking up the microwave and sniffing the aroma from a freshly opened bag of popcorn. Environmental agencies are currently embroiled in an interesting jurisdictional overlap, at the federal and state level, over my favorite sports-viewing snack. The conflict is between the Food and Drug Administration (FDA), the Environmental Protection Agency (EPA), and the National Institute for Occupational Health and Safety (NIOSH) of the Occupational Health and Safety Admistration (OSHA). The problem involves dozens of workers around the US who have developed a debilitating lung disease called bronchiolitis obliterans, otherwise known as “popcorn worker's lung”, and other respiratory diseases, from exposure to fumes from the artificial butter flavoring, diacetyl, in microwave popcorn. The EPA regulates hazardous ambient air pollutants through the Clean Air Act (CAA) and the manufacture and distribution of imminently hazardous chemical substances under the Toxic Substances Control Act (TSCA), while OSHA is responsible for the regulation of airborne contaminants in the workplace. To add salt to the popcorn wound, the FDA governs food additives, of which diacetyl is one, and while it considers the chemical safe as an edible product, the problem lies with the form of exposure. Consumer inhalation does not fall under the jurisdiction of any of these agencies. In the 1990s, NIOSH conducted several studies that confirmed the link between occupational exposure to artificial butter flavoring and lung disease. In 2000, NIOSH issued recommendations to a Missouri microwave popcorn plant about protecting workers from this hazard, and in 2003 they sent an alert, recommending safeguards, to 4000 companies that might use or make butter flavoring. In the much larger food processing industry, however, tens of thousands of workers are estimated to work with such flavorings. In March of this year, California Assemblywoman Sally Lieber introduced a bill that would ban diacetyl in the state's workplace by 2010, and Cal-OSHA drafted a standard on occupational exposure to food flavorings. But the FDA remains stubborn – FDA Commissioner Von Eschenbach responded to a Congressional inquiry in May 2007 that “the agency does not have evidence that would cause it to take immediate action with respect to diacetyl” and that it will continue to monitor the issue. Citing OSHA's unwillingness to act, Representatives Lynn Woolsey and George Miller introduced in June of this year legislation that would require OSHA to set an interim and final standard for occupational exposure to diacetyl. The EPA has made a study of the harmful effects of breathing diacetyl fumes, but it is not yet public. One may, however, draw conclusions from the fact that at least one manufacturer of microwave popcorn announced it was reformulating its flavorings to eliminate diacetyl. Three months ago, Cecile Rose, an expert in occupational and environmental medicine at Denver's National Jewish Medical and Research Center, wrote to the FDA, the Centers for Disease Control and Prevention (CDC), the EPA, and OSHA, informing the agencies about a patient “with significant lung disease, whose clinical findings are similar to those described in affected workers, but whose only inhalational exposure is as a heavy, daily consumer of butter-flavored microwave popcorn”. While it is impossible to make sweeping judgments based on one case, the response to Rose is worrisome. The FDA simply isn't buying this as a reason for taking diacetyl off the GRAS list, while the EPA has undertaken a study of the inhalation effects and has apparently shared it with popcorn companies, but hasn't released the information publicly. The CDC reportedly didn't respond to Rose's inquiry at all. Perhaps OSHA will respond to Congressional action, but they are not charged with responsibility to consumers. Maybe the microwave popcorn and flavorings industries have indeed gotten the message. The flavoring manufacturers' trade association, known by the unfortunate acronym “FEMA”, stated: “out of an abundance of caution, FEMA recommends that its members who manufacture butter flavors containing diacetyl for use in microwave popcorn consider reducing the diacetyl content of these flavors to the extent possible”. Hopefully, some agency will solve this problem soon, because I've got a tense pro football season to deal with.

Mushroom worker's lung: organic dust exposure in the spawning shed

Two people employed for several years in the spawning shed of a mushroom farm developed mushroom worker's lung. The first patient presented in respiratory failure, with radiological features characteristic of hypersensitivity pneumonitis. The condition of the second patient was subacute on presentation, with a computed tomography (CT) scan showing ground-glass opacities. With absence from the workplace and no steroid therapy, the symptoms of both patients subsided and the results of lung function tests and CT scans improved markedly.

The bacterial profile of cotton lint from worldwide origins, and links with occupational lung disease

Byssinosis, the cotton worker's lung disease persists today in many countries. Several agents have been investigated with respect to causality; among these are Gram-negative bacteria. These organisms are a source of lipopolysaccharide toxins, which are potentially hazardous to the respiratory tract. Despite byssinosis being most prevalent in countries where adequate preventive procedures are lacking, the majority of past studies have been conducted on cotton from the United States. The current investigation, involved the identification of Gram-negative bacteria from cotton lint samples originating in 12 world regions. The current investigation, involved the identification of Gram-negative bacteria from cotton lint samples originating in 12 world regions. Building a bacterial profile of cotton samples with worldwide origins will be useful in isolating sources of these organisms, assessing the risk posed to industry, workers and ultimately assisting the prevention of byssinosis and related conditions.

Popcorn worker's lung: In vitro exposure to diacetyl, an ingredient in microwave popcorn butter flavoring, increases reactivity to methacholine☆

Workers who inhale microwave popcorn butter flavorings experience decrements in lung function and can develop clinical bronchiolitis obliterans, i.e., "popcorn worker's lung" (Kreiss, K., Gomaa, A., Kullman, G., Fedan, K., Simoes, E.J., Enright, P.L., 2002. Clinical bronchiolitis obliterans in workers at a microwave-popcorn plant. N. Engl. J. Med. 347, 330-338.). In a rat inhalation model, vapors of an artificial butter flavoring damaged the epithelium of the upper and lower airways (Hubbs, A.F., Battelli, L.A., Goldsmith, W.T., Porter, D.W., Frazer, D., Friend, S., Schwegler-Berry, D., Mercer, R.R., Reynolds, J.S., Grote, A., Castranova, V., Kullman, G., Fedan, J.S., Dowdy, J., Jones, W.G., 2002. Necrosis of nasal and airway epithelium in rats inhaling vapors of artificial butter flavoring. Toxicol. Appl. Pharmacol. 185, 128-135.). Diacetyl, a butter flavoring component, is a major volatile ketone in the popcorn-processing workplace. We investigated the effects of diacetyl on epithelium of guinea pig isolated airway preparations and the effects of diacetyl in vitro on reactivity to bronchoactive agents. In the isolated, perfused trachea preparation, diacetyl added to the intraluminal (mucosal) bath elicited responses that began with contraction (threshold ca. 3 mM) and ended with relaxation. After a 4-h incubation with intraluminal diacetyl (3 mM), contractions to extraluminal (serosal) methacholine (MCh) were slightly increased; however, sensitivity to intraluminally (mucosally) applied MCh was increased by 10-fold. Relaxation responses of MCh (3 x 10(-7) M)-contracted tracheas to extraluminally applied terbutaline and intraluminally applied 120 mM KCl, to evoke epithelium-derived relaxing factor release, were unaffected by diacetyl. Exposure of the tracheal epithelium in Ussing chambers to diacetyl decreased transepithelial potential difference and resistance. These findings suggest that diacetyl exposure compromised epithelial barrier function, leading to hyperreactivity to mucosally applied MCh. The respiratory epithelium appears to serve as an initial target for the toxic effects of diacetyl in the airways.

Hypersensitivity Pneumonitis Induced by Spores of Penicillium citrinum in a Worker Cultivating Enoki Mushroom

A 47-year-old Japanese woman was admitted to our hospital with a 2-week history of dry cough and shortness of breath. She had been engaged in Enoki mushroom production for 22 years. Chest X-ray and chest computed tomography (CT) scan showed bilateral fine-nodular shadows and ground glass opacity. Bronchoalveolar lavage fluid demonstrated an increase of total cell counts with predominant lymphocytosis. Pathological specimens obtained by video-assisted thoracoscopic surgery revealed alveolitis and noncaseating granuloma with giant cells. Lymphocyte stimulation test showed positive responses with Enoki mushroom, culture medium, and Penicillium citrinum. On double immunodiffusion test, a precipitation line was observed between patient's serum and Penicillium citrinum antigen. She was found to have hypersensitivity pneumonitis caused by Penicillium citrinum. This is the first report of mushroom worker's lung caused by Penicillium citrinum.

Identification of an Organism Associated with Mushroom Worker's Lung

Saccaromonospora viridis is a thermophilic actinomycetes organism which is found in mushroom compost, as well as being a causal agent of mushroom worker's lung (MWL) and other hypersensitivity pneumonitis conditions, including farmer's lung. Phenotypically, it is difficult to distinguish the seven species described for this genus based solely on chemtaxonomic characterization, therefore it was the aim of this study to examine partial 16S rDNA PCR amplification and direct sequencing, as an improved molecular means of identification of Saccharomonospora viridis, associated with MWL. The approach adopted in this study was to identify hypervariable regions within the 16S rRNA gene, which could be employed as signature sequences of the seven individual species within this genus and to employ highly conserved flanking primers to allow initial PCR amplification, prior to direct DNA sequencing of the 16S rDNA amplicon, in a partial 16S rDNA-sequence typing technique. Four universal 16S rDNA primer combinations [P11P/P13P, PSL/PSR, XB1(SV)/PSR and XB1(SV)/P13P] were compared for their ability to identify an unknown thermophilic Saccharomonospora organism from MWL. All PCR primer combinations coupled with direct sequencing allowed for the successful identification of the MWL isolate as S. viridis, demonstrating that universal 16S rDNA PCR primer pairs examined, including the P11P/P13P primer pair, flank regions within the 16S rRNA gene, of sufficient hypervariability to be able to reliably differentiate S. viridis from the other species within this genus. This approach may therefore be useful in the identification of Saccharomonospora spp. associated with composting, as well as with allergic alveolitis or pneumonitis associated occupational exposure in agricultural and horticultural environments, including mushroom production.

Fungi and the Indoor Environment: Their Impact on Human Health

Publisher Summary This chapter elucidates the role of fungi in the phenomenon of sick building syndrome (SBS). The most common symptoms of SBS are fatigue, runny nose, itchy eyes, sore throat, and headaches. Although no single cause for the above symptoms is likely to be found, the presence of certain molds is becoming increasingly associated with this phenomenon. Several studies suggest that the elevation of culturable Penicillium species conidia in the indoor air over the levels in the outside air causes health problems in human beings. The inhalation of Penicillium species conidia is associated with the initiation of an asthmatic attack. Alternaria species spores and Penicillium species conidia provoke immediate and delayed-type asthma in individuals already sensitized to these organisms. Penicillium species conidia tends to colonize the heating, ventilation, and air conditioning (HVAC) systems of buildings. There is one other important respiratory disease caused by the inhalation of Penicillium species conidia : cheese worker's lung or cheese washer's disease, an occupational disease.

Thin-section CT findings in flock worker's lung, a work-related interstitial lung disease.

To characterize the thin-section computed tomographic (CT) features of flock worker's lung (FWL) and to determine whether these features may be used to distinguish workers with FWL from flock workers who do not fulfill diagnostic criteria for FWL. Thin-section CT images obtained in 43 flock workers (including 11 with FWL) were reviewed independently by radiologists blinded to occupational and clinical details. CT features recorded included ground-glass opacities, consolidation, micronodules, reticular abnormality, and septal thickening. Thirty-five of the CT scans (including nine obtained in patients with FWL) were also studied by using quantitative image analysis. The Student t test was used to compare mean lung attenuation between the workers with FWL and those without it. Every patient with FWL and 19 (59%) of the 32 exposed flock workers who did not meet criteria for the disease had an abnormal thin-section CT scan. The most common findings in FWL were ground-glass opacities and micronodules. Quantitative analysis showed a mean lung attenuation of -736.4 HU in patients with FWL, compared with -775.0 HU in workers without the disease (P <.05). While ground-glass opacities, micronodules, or both were found in all cases of FWL, these abnormalities were also present in a substantial proportion of symptomatic flock workers who did not satisfy current criteria for FWL. Although nonspecific, these findings should suggest the diagnosis of FWL in exposed individuals.

Improved molecular identification of Thermoactinomyces spp. associated with mushroom worker's lung by 16S rDNA sequence typing.

Mushroom worker's lung (MWL) is a hypersensitivity pneumonitis or allergic alveolitis caused by a type III IgG-mediated immunopathogenic inflammatory reaction in the host due to the inhalation of several thermophilic organisms, including Thermoactinomyces spp. It is difficult to distinguish phenotypically the eight species of this genus; therefore, this study sought to develop an improved molecular means of identifying Thermoactinomyces spp. associated with MWL by partial 16S rDNA PCR amplification and direct sequencing. Hypervariable regions within the 16S rRNA gene, which could be employed as signature sequences of the eight individual species, were identified and employed with highly conserved flanking primers to allow initial PCR amplification, before direct DNA sequencing of the 16S rDNA amplicons. A novel 24-mer 16S rDNA oligonucleotide upstream primer was designed from in silico alignments of all Thermoactinomyces spp. and was employed in combination with downstream (reverse) 16S rDNA primers. This permitted the successful identification of all four isolates associated with mushroom workers' lung. The method may be useful in the identification of Thermoactinomyces spp. associated with allergic alveolitis or pneumonitis associated with occupational exposure in agricultural and horticultural environments.

Mushroom Worker's Lung Caused by Spores of Hypsizigus marmoreus (Bunashimeji): Elevated Serum Surfactant Protein D Levels

This is a report on two patients with occupational hypersensitivity pneumonitis (HP) caused by spores of Hypsizigus marmoreus (Bunashimeji) and serial follow-up measurements of serum surfactant protein D (SP-D) levels. The diagnosis of HP was confirmed immunologically by the detection of serum precipitins to spores of Bunashimeji, but not to other antigens, and by the positive results of in vitro lymphocyte proliferative response for Bunashimeji antigens using BAL fluid lymphocytes. This is the first case report of HP caused by Bunashimeji. Serum SP-D levels for the two patients (493 and 226 ng/mL; cut off level, 110 ng/mL) were elevated at diagnosis and decreased after separation from antigens following corticosteroid therapy. However, in one patient who returned to the same job, the symptoms appeared again and SP-D level also increased.

Health effects of asbestos and nonasbestos fibers.

Exposures to asbestos and synthetic fibers remain areas of great concern in the field of occupational lung disease. Despite extensive study, the health effects associated with fibers remains an area of substantial controversy. In particular, effects of fibers at relatively low doses, particularly for mesothelioma, remain a matter of evolving opinion, especially when integrated with the divergence of opinion on relative pathogenicity of different fiber types. Mechanistic studies continue to provide a window into pathogenesis and some hope for understanding dose-response relationships at the lower levels seen in contemporary Western workplaces and the general environment. Changes in clinical assessment based on use of new chest imaging techniques beyond the traditional plain film are also an area of evolution and begin to challenge B-reading as the definitive tool for noninvasive assessment of disease. Public health concerns have to a great extent been transported to the developing world where there is a strong trend toward increased use of asbestos, although it has been virtually eliminated from commerce in most developed countries. For nonasbestos fibers, the major unsettled issues are their relative potencies as carcinogens for the human lung and mesothelium and the need to sort out the relation between physical and chemical properties of these fibers and their pathogenicity. The recent discovery of "flock worker's lung" due to synthetic fibers once again alerts us to emerging diseases associated with new technologies.

Flock Worker's Lung: Broadening the Spectrum of Clinicopathology, Narrowing the Spectrum of Suspected Etiologies

Workers in the nylon flocking industry recently have been found to be at increased risk of chronic nongranulomatous interstitial lung disease. Although a spectrum of cytologic and histopathologic abnormalities has been observed, nonspecific interstitial pneumonia, lymphoid nodules, and lymphocytic bronchiolitis predominated in the 19 previously reported cases of flock worker's lung. Here we describe five additional patients who appear to expand the histopathologic spectrum and add to the evidence suggesting a causative role for respirable-sized nylon fragments. We studied all North American patients (n = 5) found in 1998 to satisfy our previous case definition of flock worker's lung. Two pulmonary pathologists independently reviewed each biopsy specimen. All five patients reported cough and dyspnea. Only one patient had crackles on chest auscultation. High-resolution CT scan, interpreted with attention to subtle ground-glass attenuation, remained a highly sensitive diagnostic test. Pulmonary function tests and plain chest radiograph were less sensitive. One patient's wedge biopsy showed previously described prototypical findings. Two others had transbronchial biopsies showing some of the same features. The fourth patient's wedge biopsy showed desquamative interstitial pneumonia. The fifth patient had bilateral synchronous adenocarcinoma but with radiographic evidence of diffuse interstitial fibrosis. These 5 patients and the 19 patients studied previously were exposed to nylon flock manufactured by a rarely used cutting technology. Findings in these five patients appear to broaden the spectrum of the clinicopathology of flock worker's lung and add to the evidence incriminating respirable-sized nylon particulates produced during the manufacture and use of rotary-cut nylon flock.

Flock Worker's Lung

Flock Worker's Lung

Bronchoprovocation Tests in the Diagnosis of Isocyanate-Induced Asthma

Over the past 25 years, investigators have continued to improve on the approach to providing nonirritant exposures for the accurate diagnosis of isocyanate-induced asthma. Although the technology used in testing has become more sophisticated and may be fairly considered the domain of the bioengineer, the chemist, and the industrial hygienist, the requirements of the physician have remained unchanged. The physician must observe the level of exposure closely and monitor the worker's symptoms and lung function. Direct physician involvement in the testing procedure remains critical to the worker's safety and for the accurate diagnosis of isocyanate-induced asthma.