Work-exacerbated Asthma Research Articles

Oscillometry in Asthma: Respiratory Modeling and Analysis in Occupational and Work-Exacerbated Phenotypes.

Asthma onset or worsening of the disease in adulthood may be associated with occupational asthma (OA) or work-exacerbated asthma (WEA). Oscillometry and respiratory modeling offer insight into the pathophysiology and contribute to the early diagnosis of respiratory abnormalities. This study aims to compare the changes due to OA and WEA and evaluate the diagnostic accuracy of this method. Ninety-nine volunteers were evaluated: 33 in the control group, 33 in the OA group, and 33 in the WEA group. The area under the receiver operator characteristic curve (AUC) was used to describe diagnostic accuracy. Oscillometric analysis showed increased resistance at 4hz (R4, p<0.001), 20hz (R20, p<0.05), R4-R20 (p<0.0001), and respiratory work (p<0.001). Similar analysis showed reductions in dynamic compliance (p<0.001) and ventilation homogeneity, as evaluated by resonance frequency (Fr, p<0.0001) and reactance area (p<0.0001). Respiratory modeling showed increased peripheral resistance (p<0.0001), hysteresivity (p<0.0001), and damping (p<0.0001). No significant changes were observed comparing OA with WEA in any parameter. For OA, the diagnostic accuracy analyses showed Fr as the most accurate among oscillometric parameters (AUC=0.938), while the most accurate from respiratory modeling was hysteresivity (AUC=0.991). A similar analysis for WEA also showed that Fr was the most accurate among traditional parameters (AUC=0.972), and hysteresivity was the most accurate from modeling (AUC=0.987). The evaluation of differential diagnosis showed low accuracy. Oscillometry and modeling have advanced our understanding of respiratory abnormalities in OA and WEA. Furthermore, our study presents evidence suggesting that these models could aid in the early diagnosis of these diseases. Respiratory oscillometry examinations necessitate only tidal breathing and are straightforward to conduct. Collectively, these practical considerations, coupled with the findings of our study, indicate that respiratory oscillometry in conjunction with respiratory modeling, may enhance lung function assessments in OA and WEA.

Cleaning Tasks and Products and Asthma Among Health Care Professionals.

Health care workers are at risk for work-related asthma, which may be affected by changes in cleaning practices. We examined associations of cleaning tasks and products with work-related asthma in health care workers in 2016, comparing them with prior results from 2003. We estimated asthma prevalence by professional group and explored associations of self-reported asthma with job-exposure matrix-based cleaning tasks/products in a representative Texas sample of 9914 physicians, nurses, respiratory/occupational therapists, and nurse aides. Response rate was 34.8% (n = 2421). The weighted prevalence rates of physician-diagnosed (15.3%), work-exacerbated (4.1%), and new-onset asthma (6.7%) and bronchial hyperresponsiveness symptoms (31.1%) were similar to 2003. New-onset asthma was associated with building surface cleaning (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.10-3.33), use of ortho-phthalaldehyde (OR, 1.77; 95% CI, 1.15-2.72), bleach/quaternary compounds (OR, 1.91; 95% CI, 1.10-3.33), and sprays (OR, 1.97; 95% CI, 1.12-3.47). Prevalence of asthma/bronchial hyperresponsiveness seems unchanged, whereas associations of new-onset asthma with exposures to surface cleaning remained, and decreased for instrument cleaning.

Disposition of Work-Related Asthma in a Spanish Asthma Cohort: Comparison of Asthma Severity Between Employed and Retired Workers

Exposure to certain agents in the workplace can trigger occupational asthma or work-exacerbated asthma, both of which come under the heading of work-related asthma (WRA). Understanding the burden that WRA represents can help in the management of these patients. To assess the influence of occupation on asthma in real life and analyze the characteristics of patients with WRA included in an asthma cohort. This was a prospective multicenter study of a cohort of consecutive patients with asthma. A standardized clinical history was completed. Patients were classified as having WRA or non-WRA. All patients underwent respiratory function tests, FeNO test, and methacholine challenge (methacholine concentration that causes a 20% drop in FEV1) at the beginning of the study. They were classified into two groups, depending on their employment status: employed (group 1) or unemployed (group 2). Of the 480 patients included in the cohort, 82 (17%) received the diagnosis of WRA. Fifty-seven patients (70%) were still working. Mean age (SD) was 46 (10.69) years in group 1 and 57 (9.91) years in group 2 (P < .0001). Significant differences were observed in adherence to treatment (64.9% in group 1 vs 88% in group 2; P= .0354) and in severe asthma exacerbations (35.7% in group 1 vs 0% in group 2; P= .0172). No significant differences were observed in the rest of the variables analyzed. The burden of WRA in specialized asthma units is not negligible. The absence of differences in the severity of asthma, the treatment administered, alterations in lung function, and the number of exacerbations in those working versus not working may support the idea that advice regarding changing jobs should be customized for individual patients.

A brief narrative on work-related asthma (WRA)

Work related asthma (WRA) is caused by exposure at work known as occupational asthma (OA) or exacerbated or aggravated by exposure at workplace known as work-exacerbated asthma (WEA) or work-aggravated asthma (WAA). Worldwide, WRA remains under detected and undermanaged. Failure to detect or treat WRA leads to increased healthcare cost, morbidity and mortality. The diagnostic work-up includes clinical history and detailed occupational history, assessment of the causative agent and the objective measurements. Del Roio LC et al (2020) have developed algorithm for the diagnosis of WRA with three primary diagnostic criteria and five additional criteria. Better knowledge and understanding of clinicians and other healthcare providers about WRA is vital for early consideration of WRA diagnosis among adult patients with asthma. While Optimum awareness of general public about WRA may possibly help in initiating discussion by affected workers with their healthcare service providers. The primary prevention includes reducing the burden of WRA by evading the use of potential sensitizers and restricting their exposure and limiting to workplace asthma triggers when their use cannot be avoided.

Screening tools for work-related asthma and their diagnostic accuracy: a systematic review protocol

IntroductionWork-related asthma (WRA) refers to asthma caused by exposures at work (occupational asthma) and asthma made worse by work conditions (work-exacerbated asthma). WRA is common among working-age adults with asthma...

Prevalence of work-related asthma among Egyptian farmers in Great Cairo

Work related asthma (WRA) refers to asthma induced by exposure to sensitizing agents and/or irritants in the workplace leaving health and economic consequences. Early diagnosis can improve the prognosis of WRA permitting sometimes full recovery. This study aimed to assess the prevalence of WRA among Egyptian adult agriculture workers. A multi-center cross sectional study included 150 adult workers from 4 different farms, during the period from 2019 and 2021. All participants were subjected to full medical history, clinical examination, chest x-ray, skin prick test and CBC to detect absolute eosinophilic count. Spirometry with post bronchodilatation test (reversibility test) at the farm (in the day of insecticide aerosol and without aerosol) and after a week off the farm was also done. Age, median ± SD, was 37.67 ± 9.75 years, duration of farming occupation was 21.84 ± 10.18 years. Of the 150 participants, 11 had WRA. Of these, 6 had allergic occupational asthma, 3/11 had work exacerbated asthma and only 2/11 had irritant occupational asthma. Of the allergic subjects, 7.3% tested positive to mixed pollens, 4.7% to Alternaria, 2% to penicillium and 2% to the farm pollens. The onset of respiratory symptoms was 13.45 ± 6.93 months after start working in the farm. A statistical significance was observed between WRA and non-WRA individuals regarding age, duration of farming occupation and asthma symptoms during workday (P < 0.001). There was a statistical significance between WRA group and non-WRA group regarding FEV1, FEV1/FVC ratio carried out at work, during holidays and during spraying (P < 0.001). Absolute eosinophilic count, mean among WRA group was 0.55 ± 0.13 (×103cells/mm3) with significance between WRA and non-WRA (P= 0.001). Farming occupation may cause WRA, therefore, more attention should be given to minimize exposure and risk of inducing WRA.

Characterizing Inflammatory Cell Asthma Associated Phenotypes in Dental Health Workers Using Cytokine Profiling.

Cytokines elicit a pro-inflammatory response by modifying the airway microenvironment in patients with acute or chronic asthma. The expression pattern of several distinct cytokines could be a useful discriminator in asthma. This study aimed to identify asthma subject groupings based on common inflammatory patterns and to determine the relationship between these identified patterns and asthma-associated clinical indices. A sub-group of 76 dental healthcare workers (HCWs) identified from a larger cross-sectional study of 454 dental HCWs in five dental institutions were evaluated further. A self-administered questionnaire elicited the health and employment history of subjects. Sera were analyzed for atopic status, latex sensitization, and 12 cytokines (IL-1β, 3, 4, 5, 6, 7, 8, 10, 12p70, eotaxin, GM-CSF, TNF-α). Pre and post-bronchodilator spirometry was performed on all HCWs. Data clustering and factor analysis were used to identify inflammatory cluster patterns of cytokines. Associations between the cytokine cluster groupings and relevant asthma-associated clinical indices were determined using multivariate logistic regression. The classification of asthma subtype based on cytokine patterns demonstrated both eosinophilic and neutrophilic inflammatory responses. Four phenotypically distinct subgroups relating to the severity of inflammation (acute or chronic) of the cell types were identified. Cytokine determinants for the neutrophilic subtype included IL-1β, 6, 8, 10, 12p70, and TNF-α whereas for the eosinophilic subtype these included IL-3, 4, 5, 7, eotaxin, and GM-CSF. The multivariate models showed a significant association between work-related chest symptoms and all four inflammatory patterns. However, stronger associations were observed for the acute neutrophilic (OR = 6.00, p < 0.05) compared to acute and chronic eosinophilic responses (OR = 4.30, p < 0.05; OR = 4.93, p < 0.05), respectively. Subjects with airway obstruction were more likely to have a mixed cellular infiltrate. The odds of work-exacerbated asthma were increased in acute or chronic eosinophilia (OR = 7.75 and 8.12; p < 0.05), respectively as well as with acute neutrophilia (OR = 6) sub-type. This study demonstrated that neutrophilic inflammatory cell asthma phenotypes coexist with eosinophilic inflammatory phenotypes suggesting a possible dual pathway for asthma in dental health workers, probably due to mixed exposures to high molecular weight (e.g., latex) and low molecular weight (e.g., acrylates) agents.

L’asthme professionnel et l’asthme aggravé par le travail. Quelles différences en termes de facteurs de risque et d’aptitude au travail ?

IntroductionAllergic asthma is currently the most frequent respiratory pathology in the workplace. Whether induced or aggravated by the work environment, the adequacy between this morbid state and work is often subject to re-evaluation. Aim to studyThe socio-professional, clinical, para-clinical and medico-legal characteristics of allergic asthma observed in the workplace, to assess their impact on the ability to work and to compare occupational asthma (OA) and work exacerbated asthma (WEA) in terms of associated professional and extra-professional factors and in terms of repercussions on aptitude. MethodsExhaustive retrospective descriptive study of all work-related allergic asthma files (OA and WEA), collected from the Department of Occupational Medicine and Occupational Pathologies of the University Hospital La Rabta in Tunis during the period from 1 January 2000 to December 31, 2020. ResultsThis is a series of 232 cases of work-related allergic asthma, including 76.7% OA and 23.3% WEA. The mean age of the patients was 40.28±8.96 years. The female gender was represented in 50.9% of cases. A personal history of atopy was reported by 16.5% of patients. The most represented professional category was that of unskilled workers (57.1%) with an average seniority of 11.43±7.96 years. The sectors that provided the most asthma were the textile sector (10%) and the health sector (10.9%). The clinical symptoms were dominated by paroxysmal wheezing dyspnea (51.5%), punctuated by work. in the majority (86.6%). The responsible agents were high molecular weight allergens (HMW) in particular vegetable textile dust (9.9%), low molecular weight (LMW) such as isocyanate (11.6%), formaldehyde (11.2%) as well as respiratory irritants, mainly mold (7.8%) and non-specific dust (3.9%). Asthma justified a workstation adaptation in 47.8% of cases and a mutation in 40.9% of patients.Comparing the cases of work-induced asthma with those that were exacerbated, we found that age and length of service were higher in the OA group, (P=0.002) and (P=0.005). In addition, this group was also associated with the grade of unskilled worker (P=0.035), exposure to HMW allergens (P=0.008), as well as the prescription for a job transfer (P≤10-3). In addition, WEA was associated with a history of personal and family atopy with respectively (P≤10–3) and (P=0.017), work in the transport sector (P≤10-3) as well as prescription temporary unfitness for the post (P≤10–3). ConclusionThe etiologies of OA and WEA differ. Indeed, the etiologies of WEA are essentially respiratory irritants while in the OA are HMW allergens. In terms of aptitude, the impact on OA is more pejorative than WEA involving more mutation.

Pulmonary Function Testing in Work-Related Asthma: An Overview from Spirometry to Specific Inhalation Challenge.

Work-related asthma (WRA) is a very frequent condition in the occupational setting, and refers either to asthma induced (occupational asthma, OA) or worsened (work-exacerbated asthma, WEA) by exposure to allergens (or other sensitizing agents) or to irritant agents at work. Diagnosis of WRA is frequently missed and should take into account clinical features and objective evaluation of lung function. The aim of this overview on pulmonary function testing in the field of WRA is to summarize the different available tests that should be considered in order to accurately diagnose WRA. When WRA is suspected, initial assessment should be carried out with spirometry and bronchodilator responsiveness testing coupled with first-step bronchial provocation testing to assess non-specific bronchial hyper-responsiveness (NSBHR). Further investigations should then refer to specialists with specific functional respiratory tests aiming to consolidate WRA diagnosis and helping to differentiate OA from WEA. Serial peak expiratory flow (PEF) with calculation of the occupation asthma system (OASYS) score as well as serial NSBHR challenge during the working period compared to the off work period are highly informative in the management of WRA. Finally, specific inhalation challenge (SIC) is considered as the reference standard and represents the best way to confirm the specific cause of WRA. Overall, clinicians should be aware that all pulmonary function tests should be standardized in accordance with current guidelines.

Work-related asthma.

ABSTRACTWork-related asthma (WRA) is highly prevalent in the adult population. WRA includes occupational asthma (OA), which is asthma caused by workplace exposures, and work-exacerbated asthma (WEA), also known as work-aggravated asthma, which is preexisting or concurrent asthma worsened by workplace conditions. In adults, the estimated prevalence of OA is 16.0%, whereas that of WEA is 21.5%. An increasing number of chemicals used in industrial production, households, and services are associated with the incidence of adult-onset asthma attributable to exposure to chemicals. This review article summarizes the different types of WRA and describes diagnostic procedures, treatment, prevention, and approaches to patient management. It is not always easy to distinguish between OA and WEA. It is important to establish a diagnosis (of sensitizer-/irritant-induced OA or WEA) in order to prevent worsening of symptoms, as well as to prevent other workers from being exposed, by providing early treatment and counseling on social security and work-related issues.

Clinical Importance of Work-Exacerbated Asthma: Findings From a Prospective Asthma Cohort in a Highly Industrialized City in Korea.

PurposeWork-related asthma (WRA) occupies about 10%–30% of all asthma cases. Among 2 subtypes of WRA (occupational asthma [OA] and work-exacerbated asthma [WEA]), the rate of WEA has been reported to increase recently. WRA is described as having worse characteristics than non-WRA (NWRA), while WEA is known to show similar severity to OA in terms of symptoms and exacerbations. However, these data were mainly based on indirect surveys. Ulsan is a highly industrialized city in Korea; therefore, it is estimated to have a high incidence of WRA. This study aimed to identify the characteristics of WRA in the city.MethodsThis was a prospective asthma cohort study of individuals diagnosed with asthma and treated at Ulsan University Hospital between Jan 2015 and Dec 2016. Baseline characteristics and work-related inquiry (9 questionnaires) were investigated at enrollment. Various severity indices and job change were then investigated for the longitudinal analysis at 12 months after enrollment.ResultsIn total, 217 asthma patients completed the study. WRA accounted for 17% (36/217), with an equal number of WEA and OA (18 patients each). Before the work-related survey, only 33% (n = 12) of WRA patients (22% [4/18] of WEA and 44% [8/18] of OA) were diagnosed with WRA by the attending physicians. Compared to the NWRA group and the OA subgroup, the WEA subgroup had more outpatient visits, more oral corticosteroids prescriptions, and trends of low asthma control test scores and severe asthma. The rate of job change was markedly lower in the WEA subgroup than in the OA subgroup (20% vs. 5%).ConclusionsThe overall prevalence of WRA (17%) was similar to those of previous studies, but the share of WEA was high (50% of WRA). WEA was more severe than OA or NWRA. The possible reason for this severity is ongoing workplace exposure.

Causes and Phenotypes of Work-Related Asthma.

Work-related asthma (WRA) includes heterogeneous conditions, which have in common (i) symptoms and signs compatible with asthma and (ii) a relationship with exposures in the workplace. The types of WRA described in this review are distinguished by their etiology, comprising of work-exacerbated asthma (WEA), irritant-induced asthma (IIA), and immunologic occupational asthma (OA). There have been significant advances in the definition and characterization of the different forms of WRA by international panels of experts. The present review provides a comprehensive and updated view of the current knowledge on causes and phenotypes of WRA. Health care practitioners should consider WRA in any case of adult asthma, given that one fifth of workers with asthma report symptoms of WEA and it has been estimated that OA represents 10% to 25% of asthma in adulthood. The information provided in this review will facilitate the physician in the recognition of the different forms of WRA, since it has been established that five categories of agents are responsible for at least 60% of WEA cases and seven groups of agents are the cause of 70% of immunologic OA. In addition, there is agreement that IIA can be elicited not only by a single massive irritant exposure, but also by low/moderate repeated irritant exposures.

P.051 Improvements in workplace productivity in working patients with major depressive disorder: results from the AtWoRC study

Work-related asthma (WRA) is the most common chronic occupational lung disease in the developed world. Several factors including sociodemographic status and occupation/industry increase the risks of developing WRA. In this study, we sought to identify changes in patterns and characteristics among patients with WRA over a 15-year period in an occupational lung disease clinic.We performed a retrospective analysis of patients with WRA charts at the Occupational Lung Disease Clinic of a University Hospital in Toronto, Canada. Patients were divided into two periods classified by first attendance at the clinic 2000 through 2007 and 2008 through 2015. Comparisons between the two periods included: sociodemographic characteristics, smoking status, occupations, exposures, and submitted workers’ compensation claims.Fewer occupational asthma cases were seen in the more recent period vs the earlier period (40 vs 74 cases), with a smaller reduction in work-exacerbated asthma cases (40 vs 58). The recent period included a significantly smaller proportion employed in the manufacturing industry and isocyanate-induced cases compared with the earlier period. An increased proportion were employed in health-care and education industries (primarily cleaners and teachers) in the recent period, consistent with a corresponding increased frequency of cleaning agents and dust exposures.The changes observed in work sectors in the patients with WRA in this clinic in Toronto are consistent with reductions reported in Ontario workers’ compensation claims for occupational asthma and may relate to preventive measures. Cleaners and teachers should be a focus of further intervention measures for work-related asthma.

Allergen-specific IgE to recombinant latex allergens in occupational allergy diagnostics.

ObjectivesSpecific challenge tests (SICs) are considered reference tests for allergic occupational diseases diagnosis. However, in numerous cases, SICs cannot be carried out in the diagnosis of allergy to latex due to the risk of generalized reactions. The aim of the study was to evaluate the usefulness of sIgE determination to recombinant latex allergens in diagnostics of occupational respiratory allergy.Materials and MethodsThe study group comprised 44 healthcare workers (HCW) suspected of suffering from occupational respiratory allergy to latex (they underwent a physical examination, skin‐prick tests (SPTs) to common and latex allergens, spirometry and SIC) and 17 controls not occupationally exposed to latex, with a positive sIgE against latex. Each serum was tested for allergen‐specific IgE to aeroallergens, latex, eight recombinant latex allergens and CCD‐markers.ResultsSpecific IgE against Hev b5, 6.01, and 6.02 were significantly more frequently detected in HCWs and their mean serum levels were higher compared with the control group. In 26 HCWs with occupational asthma (OA), sensitization to Hev b5, Hev b6.01, Hev b6.02 was significantly more frequent than in 18 HCWs with work‐exacerbated asthma (WEA); they had positive results SPT to latex significantly more frequently in comparison with subjects with WEA.ConclusionsTest for recombinant latex allergens is much more accurate in recognition of latex allergy than test for latex extract, which seems to produce false‐positive results in patients with pollen allergy. The measurements of sIgE against recombinant latex allergens Hev b 6.01, 6.02, 5, and 8 are useful in differentiating OA from WEA.

Occupational Asthma or Work-exacerbated asthma?

Currently there is an increase in the prevalence of asthma and it seems that occupational exposure is one of the factors contributing to this increase. "Occupational asthma" refers to new onset asthma induced by exposure to a substance in the workplace, whereas "workaggravated asthma" refers to pre-existing asthma that is then exacerbated in the workplace. A correct diagnosis requires a high index of suspicion and establishing a temporal relationship between symptoms and work. An incorrect diagnosis can lead to important socioeconomic consequences for the worker. In Spain, Royal Order 1299/2006 on 10 November (amended on May 4, 2018) establishes the criteria for its classification and official recognition. In the context of an allergic process, an occupational etiology should be considered and occupational physicians in an occupational healht service can serve as consultants to guide and manage these cases. In this case report we established an association between an occupational exposure and asthma in a worker which led to a series of steps resulting in its acceptance as an occupational disease.

Update on the Management of Occupational Asthma and Work-Exacerbated Asthma.

Work-related asthma is the most common occupational lung disease encountered in clinical practice. In adult asthmatics, work-relatedness can account for 15%–33% of cases, but delays in diagnosis remain common and lead to worse outcomes. Accurate diagnosis of asthma is the first step to managing occupational asthma, which can be sensitizer-induced or irritant-induced asthma. While latency has traditionally been recognized as a hallmark of sensitizer-induced asthma and rapid-onset a defining feature of irritant-induced asthma (as in Reactive Airway Dysfunction Syndrome), there is epidemiological evidence for irritant-induced asthma with latency from chronic moderate exposure. Diagnostic testing while the patient is still in the workplace significantly improves sensitivity. While specific inhalational challenges remain the gold-standard for the diagnosis of occupational asthma, they are not available outside of specialized centers. Commonly available tests including bronchoprovocation challenges and peak flow monitoring are important tools for practicing clinicians. Management of sensitizer-induced occupational asthma is notable for the central importance of removal from the causative agent: ideally, removal of the culprit agent; but if not feasible, this may require changes in the work process or ultimately, removal of the worker from the workplace. While workers' compensation programs may reduce income loss, these are not universal and there can be significant socio-economic impact from work-related asthma. Primary prevention remains the preferred method of reducing the burden of occupational asthma, which may include modification to work processes, better worker education and substitution of sensitizing agents from the workplace with safer compounds.

Work-related asthma from cleaning agents versus other agents.

Cleaning agents have been commonly implicated as causative or triggering factors in work-related asthma (WRA), mainly from epidemiologic studies. Relatively few clinical series have been reported. We aimed to compare socio-demographic and clinical features among tertiary clinic patients with WRA exposed to cleaning and non-cleaning products. Analyses were conducted on a patient database containing 208 patients with probable WRA referred to the asthma and airway centre at a tertiary centre hospital in Canada from 2000 to 2014. Chi-squared and independent samples t-tests were used to analyse categorical and continuous data, respectively. Twenty-two (11%) WRA cases were attributed to a variety of cleaning product exposures, 12 were diagnosed as occupational asthma (OA) and 10 as work-exacerbated asthma (WEA) (10% of all OA and 11% of all WEA). There were multiple exposures and the responsible agent(s) could seldom be clearly identified. Most frequent categories of exposure were surfactants, alcohols, disinfectants and acids. Compared to WRA with other exposures, those with cleaning agent exposures had a significantly larger proportion of females (82 versus 35%, P < 0.001), included a higher percentage of workers in healthcare (41 versus 4%, P < 0.001), and submitted more workers' compensation claims (86 versus 64%, P = 0.05). Other characteristics were comparable. In a tertiary referral clinic, patients with WRA from cleaning agent exposure had clinical characteristics that were similar to those with WRA from other causes. Most frequent exposures were surfactants, alcohols, disinfectants and acids.

Low dose of chlorine exposure exacerbates nasal and pulmonary allergic inflammation in mice

Work-exacerbated asthma (WEA) is defined as preexisting asthma that worsens with exposure to irritants [e.g., chlorine (Cl2) derivatives] in the workplace. The maximum allowable concentration in the workplace of Cl2 exposure is 3 mg/ m3 (described in OSHA). We investigated in an experimental asthma model in mice the effects of a single exposure to a sodium hypochlorite dose with this allowed chlorine concentration and a tenfold higher dose. Acute chlorine exposure at 3.3 mg/m3 in the OVA-sensitized group increased eosinophils in the peribronquial infiltrate, cytokine production, nasal mucus production and the number of iNOS positive cells in the distal lung compared to only sensitized mice. The exposure to a higher dose of 33.3 mg/m3 in the OVA-sensitized group resulted in an increase in respiratory system elastance, in the total and differential numbers of inflammatory cells in bronchoalveolar lavage fluid, IL-4, IL-5, and IL-17 in the lungs, eosinophils in peribronquial infiltrate and mucus content in nasal compared to non-exposed and sensitized animals. In this asthma model, chorine exposures at an allowable dose, contributed to the potentiation of Th2 responses. The functional alterations were associated with increased iNOS and ROCK-2 activation in the distal lung.

Reply to Voelkel: Cigarette Smoke Is an Endothelial Cell Toxin.

Asthma is a very common disease in adults, including in those who work outside the home. Work-related asthma refers to asthma that is either caused by or worsened by something at work. It is very important to know whether someone has work-related asthma because there are specific ways to manage it. There are two types of work-related asthma: occupational asthma and work-exacerbated asthma. Occupational asthma is when something at work causes you to have new onset asthma. Work-exacerbated asthma (WEA) means the asthma you already have been diagnosed with is being made worse from something at work. Typically this occurs when substances present in that workplace trigger asthma symptoms. This fact sheet will tell you more about WEA.

Work-exacerbated Asthma.

Asthma is a very common disease in adults, including in those who work outside the home. Work-related asthma refers to asthma that is either caused by or worsened by something at work. It is very important to know whether someone has work-related asthma because there are specific ways to manage it. There are two types of work-related asthma: occupational asthma and work-exacerbated asthma. Occupational asthma is when something at work causes you to have new onset asthma. Work-exacerbated asthma (WEA) means the asthma you already have been diagnosed with is being made worse from something at work. Typically this occurs when substances present in that workplace trigger asthma symptoms. This fact sheet will tell you more about WEA.