Impact of Wildfires on Cardiovascular Health.

Wildfire smoke (WFS) is a mixture of respirable particulate matter, environmental gases, and other hazardous pollutants that originate from the unplanned burning of arid vegetation during wildfires. The increasing size and frequency of recent wildfires has escalated public and occupational health concerns regarding WFS inhalation, by either individuals living nearby and downstream an active fire or wildland firefighters and other workers that face unavoidable exposure because of their profession. In this review, we first synthesize current evidence from environmental, controlled, and interventional human exposure studies, to highlight positive associations between WFS inhalation and cardiovascular morbidity and mortality. Motivated by these findings, we discuss preventative measures and suggest interventions to mitigate the cardiovascular impact of wildfires. We then review animal and cell exposure studies to call attention on the pathophysiological processes that support the deterioration of cardiovascular tissues and organs in response to WFS inhalation. Acknowledging the challenges of integrating evidence across independent sources, we contextualize laboratory-scale exposure approaches according to the biological processes that they model and offer suggestions for ensuring relevance to the human condition. Noting that wildfires are significant contributors to ambient air pollution, we compare the biological responses triggered by WFS to those of other harmful pollutants. We also review evidence for how WFS inhalation may trigger mechanisms that have been proposed as mediators of adverse cardiovascular effects upon exposure to air pollution. We finally conclude by highlighting research areas that demand further consideration. Overall, we aspire for this work to serve as a catalyst for regulatory initiatives to mitigate the adverse cardiovascular effects of WFS inhalation in the community and alleviate the occupational risk in wildland firefighters.

Tularemia From Veterinary Occupational Exposure.

Tularemia is a disease caused by Francisella tularensis, a highly infectious bacteria that can be transmitted to humans by direct contact with infected animals. Because of the potential for zoonotic transmission of F. tularensis, veterinary occupational risk is a concern. Here, we report on a human case of tularemia in a veterinarian after an accidental needlestick injury during abscess drainage in a sick dog. The veterinarian developed ulceroglandular tularemia requiring hospitalization but fully recovered after abscess drainage and a course of effective antibiotics. To systematically assess veterinary occupational transmission risk of F. tularensis, we conducted a survey of veterinary clinical staff after occupational exposure to animals with confirmed tularemia. We defined a high-risk exposure as direct contact to the infected animal's body fluids or potential aerosol inhalation without use of standard personal protective equipment (PPE). Survey data included information on 20 veterinary occupational exposures to animals with F. tularensis in 4 states. Veterinarians were the clinical staff most often exposed (40%), followed by veterinarian technicians and assistants (30% and 20%, respectively). Exposures to infected cats were most common (80%). Standard PPE was not used during 80% of exposures; a total of 7 exposures were categorized as high risk. Transmission of F. tularensis in the veterinary clinical setting is possible but overall risk is likely low. Veterinary clinical staff should use standard PPE and employ environmental precautions when handling sick animals to minimize risk of tularemia and other zoonotic infections; postexposure prophylaxis should be considered after high-risk exposures to animals with suspected or confirmed F. tularensis infection to prevent tularemia.

Creatinine clearance is maintained in a range of wet-bulb globe temperatures and work-rest ratios during simulated occupational heat stress.

We tested the hypothesis that compliance with the National Institute for Occupational Safety and Health (NIOSH) heat stress recommendations will prevent reductions in glomerular filtration rate (GFR) across a range of wet-bulb globe temperatures (WBGTs) and work-rest ratios at a fixed work intensity. We also tested the hypothesis that noncompliance would result in a reduction in GFR compared with a work-rest matched compliant trial. Twelve healthy adults completed five trials (four NIOSH compliant and one noncompliant) that consisted of 4 h of exposure to a range of WBGTs. Subjects walked on a treadmill (heat production: approximately 430 W) and work-rest ratios (work/h: 60, 45, 30, and 15 min) were prescribed as a function of WBGT (24°C, 26.5°C, 28.5°C, 30°C, and 36°C), and subjects drank a sport drink ad libitum. Peak core temperature (TC) and percentage change in body weight (%ΔBW) were measured. Creatinine clearance measured pre- and postexposure provided a primary marker of GFR. Peak TC did not differ among NIOSH-compliant trials (P = 0.065) but differed between compliant versus noncompliant trials (P < 0.001). %ΔBW did not differ among NIOSH-compliant trials (P = 0.131) or between compliant versus noncompliant trials (P = 0.185). Creatinine clearance did not change or differ among compliant trials (P ≥ 0.079). Creatinine clearance did not change or differ between compliant versus noncompliant trials (P ≥ 0.661). Compliance with the NIOSH recommendations maintained GFR. Surprisingly, despite a greater heat strain in a noncompliant trial, GFR was maintained highlighting the potential relative importance of hydration.NEW & NOTEWORTHY We highlight that glomerular filtration rate (GFR) is maintained during simulated occupational heat stress across a range of total work, work-rest ratios, and wet-bulb globe temperatures with ad libitum consumption of an electrolyte and sugar-containing sports drink. Compared with a work-rest matched compliant trial, noncompliance resulted in augmented heat strain but did not induce a reduction in GFR likely due to an increased relative fluid intake and robust fluid conservatory responses.

Recurrent Occupational Hantavirus Infections Linked to Feeder Rodent Breeding Farm, Taiwan, 2022.

We investigated 2 acute cases and 1 previous case of Seoul hantavirus infection in workers in a feeder rodent breeding farm in Taiwan. Prevalence of hantavirus IgG among the tested feeder rats was 37.5%. Appropriate prevention measures, including using disinfection protocols and personal protective equipment, are crucial to lowering risk.

Infective SARS-CoV-2 in Skull Sawdust at Autopsy, Finland.

We assessed the distribution of SARS-CoV-2 at autopsy in 22 deceased persons with confirmed COVID-19. SARS-CoV-2 was found by PCR (2/22, 9.1%) and by culture (1/22, 4.5%) in skull sawdust, suggesting that live virus is present in tissues postmortem, including bone. Occupational exposure risk is low with appropriate personal protective equipment.

Occupational asbestos exposure and risk of esophageal cancer: A systematic review and meta-analysis.

Esophageal cancer (EC), which includes squamous cell carcinoma (ESCC) and adenocarcinoma (EAC), is an important cancer with poor prognosis and high mortality rate. Several occupational exposures have been associated with EC. We aim to investigate the association between occupational asbestos exposure and EC risk, considering types of asbestos and histology of the disease. We included studies mentioned in the list of references in previous reviews and pooled analyses, and we conducted an independent search in PubMed and Scopus. Forest plots of relative risks (RR) were constructed based on the association between occupational asbestos and EC risk. Random-effects models were used to address heterogeneity between 48 independent cohort and case-control studies. We found an association between occupational asbestos exposure and EC (meta-relative risk [RR] = 1.20, 95% confidence interval [CI] = 1.09-1.32; I2 = 58.8%, p-heterogeneity [het] <.001). The results of stratification by job (p-het = .20) indicate an increased RR among asbestos product workers (RR = 1.39, 95% CI = 1.07-1.81), asbestos applicators (RR = 1.41, 95% CI = 1.20-1.67), and construction workers (RR = 1.12, 95% CI = 1.02-1.24). There was no heterogeneity in meta-RR according to outcome (p = .29), geographic region (p = .69), year of publication (p = .59), quality score (p = .73), asbestos type (p = .93), study design (p = .87), and gender (p = .88), control for potential confounders (p = .20), year of first employment (p = .94) and exposure level (p = .43). The stratification analysis by histology type found an increased RR for both ESCC 1.33(1.03-1.71) and EAC 1.45(1.03-2.04) (p-het = .68). We didn't find evidence of publication bias (p = .07). The results of our study suggest that occupational asbestos exposure is associated with an increased risk of EC in both histology types.

Risk of hypersensitivity pneumonitis and other interstitial lung diseases following organic dust exposure.

BACKGROUND: Organic dust is associated with hypersensitivity pneumonitis, and associations with other types of interstitial lung disease (ILD) have been suggested. We examined the association between occupational organic dust exposure and hypersensitivity pneumonitis and other ILDs in a cohort study. METHODS: The study population included all residents of Denmark born in 1956 or later with at least 1 year of gainful employment since 1976. Incident cases of hypersensitivity pneumonitis and other ILDs were identified in the Danish National Patient Register 1994-2015. Job exposure matrices were used to assign individual annual levels of exposure to organic dust, endotoxin and wood dust from 1976 to 2015. We analysed exposure-response relations by different exposure metrics using a discrete-time hazard model. RESULTS: For organic dust, we observed increasing risk with increasing cumulative exposure with incidence rate ratios (IRR) per 10 unit-years of 1.19 (95% CI 1.12 to 1.27) for hypersensitivity pneumonitis and 1.04 (95% CI 1.02 to 1.06) for other ILDs. We found increasing risk with increasing cumulative endotoxin exposure for hypersensitivity pneumonitis and other ILDs with IRRs per 5000 endotoxin units/m3-years of 1.55 (95% CI 1.38 to 1.73) and 1.09 (95% CI 1.00 to 1.19), respectively. For both exposures, risk also increased with increasing duration of exposure and recent exposure. No increased risks were observed for wood dust exposure. CONCLUSION: Exposure-response relations were observed between organic dust and endotoxin exposure and hypersensitivity pneumonitis and other ILDs, with lower risk estimates for the latter. The findings indicate that organic dust should be considered a possible cause of any ILD. TRIAL REGISTRATION NUMBER: j.no.: 1-16-02-196-17.

A Screening Approach to the Safe-and-Sustainable-by-Design Development of Advanced Insulation Materials.

Herein, a Safe-and-Sustainable-by-Design (SSbD) screening strategy on four different inorganic aerogel mats and two conventional mineral wools for ranking purposes is demonstrated. Given that they do not consist of particles, the release is first simulated, addressing three occupational exposure scenarios, realistic for their intended use as building insulators. No exposure to consumers nor to the environment is foreseen in the use phase, however, aerosols may be released during mat installation, posing an inhalation risk for workers. All four aerogel mats release more respirable dust than the benchmark materials and 60% thereof deposits in the alveolar region according to modelling tools. The collected aerogel dust allows for subsequent screening of hazard implications via two abiotic assays: 1) surface reactivity in human blood serum; 2) biodissolution kinetics in lung simulant fluids. Both aerogels and conventional insulators show similar surface reactivity. Differences in biodissolution are influenced by the specifically designed organic and inorganic structural modifications. Aerogel mats are better-performing insulators (2-fold lower thermal conductivity than the benchmark) However, this work demonstrates how investment decisions can be balanced with safety and sustainability aspects. Concepts of analogy and similarity thus support easily accessible methods to companies for safe and economically viable innovation with advanced materials.

Postexposure prophylaxis for occupational exposure to selected pathogens for healthcare personnel.

PURPOSE OF REVIEW: Timely postexposure prophylaxis is important after an occupational exposure. Here we review select organisms, exposure opportunities in the healthcare setting, and postexposure prophylaxis regimens. RECENT FINDINGS: Needlestick injuries pose a risk of exposure to bloodborne pathogens, such as HIV, Hepatitis B, and Hepatitis C. Risk mitigation strategies should be reexamined in light of newer vaccines and therapeutics. Increased vaccine hesitancy and vaccine denialisms may foster the re-emergence of some infections that have become extremely uncommon because of effective vaccines. With increasing occurrences of zoonotic infections and the ease of global spread as evidenced by COVID-19 and mpox, healthcare exposures must also consider risks related to emerging and re-emerging infectious diseases. SUMMARY: Early recognition and reporting of occupational exposures to pathogens with available postexposure prophylaxis is key to mitigating the risk of transmission. Providers should be able to evaluate the exposure and associated risks to provide prompt and appropriate postexposure prophylaxis.

Extreme Heat and Occupational Health Risks.

Climate change poses a significant occupational health hazard. Rising temperatures and more frequent heat waves are expected to cause increasing heat-related morbidity and mortality for workers across the globe. Agricultural, construction, military, firefighting, mining, and manufacturing workers are at particularly high risk for heat-related illness (HRI). Various factors, including ambient temperatures, personal protective equipment, work arrangements, physical exertion, and work with heavy equipment may put workers at higher risk for HRI. While extreme heat will impact workers across the world, workers in low- and middle-income countries will be disproportionately affected. Tracking occupational HRI will be critical to informing prevention and mitigation strategies. Renewed investment in these strategies, including workplace heat prevention programs and regulatory standards for indoor and outdoor workers, will be needed. Additional research is needed to evaluate the effectiveness of interventions in order to successfully reduce the risk of HRI in the workplace.

Evaluation of environmental antibiotic contamination by surface wipe sampling in a large care centre.

OBJECTIVES: Exposure of healthcare workers to antibiotics may cause adverse health effects. Results of environmental contamination with antibiotics, obtained by taking surface wipe samples, can be used as an indicator for potential exposure to these sensitizing drugs. The objective was to describe the results of repeated measurements of contamination with antibiotics on multiple surfaces in hospital wards. Standardized needle and syringe preparation techniques and cleaning procedures were used. METHODS: The preparation table and the floor around the waste bin in six wards were sampled and analysed for contamination with the antibiotics amoxicillin, benzylpenicillin, cefotaxime, ceftriaxone, flucloxacillin, meropenem, piperacillin and vancomycin. Sampling was performed in four trials during 8 months. Depending on the outcome of the trials, the cleaning procedure was adapted. Liquid chromatography with tandem mass spectrometry was used for the analysis of the drugs. RESULTS: During the four trials, contamination with all eight antibiotics was omnipresent on all preparation tables and floors in the six wards. The highest contamination was found for amoxicillin (1291 ng/cm2). Changing the cleaning procedure did not reduce the level of contamination. CONCLUSIONS: Surface contamination with the antibiotics was widespread and most probably caused by spillage during the preparation in combination with an ineffective cleaning procedure. Strategies should be developed and implemented by institutions for safe handling of antibiotics to reduce environmental contamination and potential exposure of healthcare workers to these sensitizing drugs.

A procedural step analysis of radiation exposure in fenestrated endovascular aortic repair.

OBJECTIVE: Radiation exposure during complex endovascular aortic repair may be associated with tangible adverse effects in patients and operators. This study aimed to identify the steps of highest radiation exposure during fenestrated endovascular aortic repair (FEVAR) and to investigate potential intraoperative factors affecting radiation exposure. METHODS: Prospective data of 31 consecutive patients managed exclusively with four-fenestration endografts between March 1, 2020, and July 1, 2022 were retrospectively analyzed. Leveraging the conformity of the applied technique, every FEVAR operation was considered a combination of six overall stages composed of 28 standardized steps. Intraoperative parameters, including air kerma, dose area product, fluoroscopy time, and number of digital subtraction angiographies (DSAs) and average angulations were collected and analyzed for each step. RESULTS: The mean procedure duration and fluoroscopy time was 140 minutes (standard deviation [SD], 32 minutes), and 40 minutes (SD, 9.1 minutes), respectively. The mean air kerma was 814 mGy (SD, 498 mGy), and the mean dose area product was 66.8 Gy cm2 (SD, 33 Gy cm2). The percentage of air kerma of the entire procedure was distributed throughout the following procedure stages: preparation (13.9%), main body (9.6%), target vessel cannulation (27.8%), stent deployment (29.1%), distal aortoiliac grafting (14.3%), and completion (5.3%). DSAs represented 23.0% of the total air kerma. Target vessel cannulation and stent deployment presented the highest mean lateral angulation (67 and 63 degrees, respectively). Using linear regression, each minute of continuous fluoroscopy added 18.9 mGy of air kerma (95% confidence interval, 17.6-20.2 mGy), and each DSA series added 21.1 mGy of air kerma (95% confidence interval, 17.9-24.3 mGy). Body mass index and lateral angulation were significantly associated with increased air kerma (P < .001). CONCLUSIONS: Cannulation of target vessels and bridging stent deployment are the steps requiring the highest radiation exposure during FEVAR cases. Optimized operator protection during these steps is mandatory.

Effect of Pb-exposure and B vitamin deficiencies on δ-aminolevulinic acid dehydratase activity among workers from Pb recycling plants.

Previous studies reported that Pb exposure causes a negative association with delta-aminolevulinic acid dehydratase activity (δ-ALAD), but the impact of Pb exposure (dose and time), B vitamin deficiencies, and lifestyle factors needs to be explored. In this study, the impact of Pb exposure, B vitamin deficiencies, and lifestyle factors on δ-ALAD activity among workers exposed to Pb from the Pb-recycling process was evaluated. Blood lead levels (BLLs), B vitamins (B6, B9, and B12), hematological factors (Hb% and HCT), lifestyle factors, and δ-ALAD activity was assessed in 170 male Pb-exposed workers engaged in the Pb recycling process. BLLs are estimated using the ICP-OES method. B vitamins in serum samples from workers were determined using the ELISA method. The δ-ALAD activity in whole blood samples was determined using the spectrophotometer method. The lifestyle factors were collected using a standard questionnaire. The δ-ALAD activity was significantly decreased in workers with the habits of alcohol use, tobacco consumption, hematocrit < 41%, mild and moderate categories of anemia, vitamin B6 and B12 deficiency, and BLL categories of 10-30, 30-50, and > 50 µg/dL. Multiple regression analysis revealed that the independent variables of alcohol consumption (ß = - 0.170; P = 0.025), BLLs (ß = - 0.589; P = 0.001) and Hb% (ß = 0.183; P = 0.001) significantly influenced the δ-ALAD activity with 44.2% (R2 = 0.442). Among the workers exposed to Pb from the Pb recycling plant, δ-ALAD activity was considerably reduced by Pb exposure, B vitamin deficiency, hematological parameters, and lifestyle factors.

Shedding light on occupational exposure to the sun.

Roughly one in three non-melanoma skin cancer deaths worldwide is associated with working outdoors in the sun. Gary Humphreys reports.

Aristolochic Acid Exposure via Dermal Contact or Inhalation of Herbal Powders: Evidence of Occupational Exposure in Herbalists with Urothelial Cancer.

Emerging evidence showing urothelial cancer in herbalists is linked to aristolochic acid (AA) exposure; however, the exposure pathway remains unclear. Here, we show that dermal contact and inhalation of fine powders of AA-containing herbs are significant occupational AA exposure pathways for herbalists. We initiated the study by quantifying the amount of AA in the AA-containing powder deposited on gloves and face masks worn by the operators of an AA-containing herb grinding machine. Then, we measured the kinetics of dermal absorption and dissolution of AA from fine powders of AA-containing herbs into artificial sweat and surrogate lung fluid. Lastly, we quantified the mutagenic AA-DNA adduct levels formed in the kidneys of mice exposed to AA-containing fine powders through dermal contact. Our findings highlight an urgent occupational risk that should demand implementation of safety standards for herbalists exposed to AA-containing fine powders.

A systematic review of the epidemiology evidence on talc and cancer.

Over the past several decades, there have been many epidemiology studies on talc and cancer published in the scientific literature, and several reviews and meta-analyses of talc and respiratory, female reproductive, and stomach cancers, specifically. To help provide a resource for the evaluation of talc as a potential human carcinogen, we applied a consistent set of examination methods and criteria for all epidemiology studies that examined the association between talc exposure (by various routes) and cancers (of various types). We identified 30 cohort, 35 case-control, and 12 pooled studies that evaluated occupational, medicinal, and personal-care product talc exposure and cancers of the respiratory system, the female reproductive tract, the gastrointestinal tract, the urinary system, the lymphohematopoietic system, the prostate, male genital organs, and the central nervous system, as well as skin, eye, bone, connective tissue, peritoneal, and breast cancers. We tabulated study characteristics, quality, and results in a systematic manner, and evaluated all cancer types for which studies of at least three unique populations were available in a narrative review. We focused on study quality aspects most likely to impact the interpretation of results. We found that only one study, of medicinal talc use, evaluated direct exposure measurements for any individuals, though some used semi-quantitative exposure metrics, and few studies adequately assessed potential confounders. The only consistent associations were with ovarian cancer in case-control studies and these associations were likely impacted by recall and potentially other biases. This systematic review indicates that epidemiology studies do not support a causal association between occupational, medicinal, or personal talc exposure and any cancer in humans.

Characterizing the Burden of Occupational Chemical Exposures by Sociodemographic Groups in the United States, 2021.

Objectives. To estimate the number and prevalence of workers in the United States exposed to chemical hazards available in the Canadian job-exposure matrix (CANJEM) database and examine exposure disparities across sociodemographic groups. Methods. We merged US worker demographic data from the Current Population Survey with CANJEM to characterize the burden and sociodemographic distribution of 244 chemical exposures in the United States in 2021. An interactive version of the full data set is available online (https://deohs.washington.edu/us-exposure-burden). Results. Of the chemical exposures examined, the most prevalent were cleaning and antimicrobial agents (14.7% of workforce estimated exposed), engine emissions (12.8%), organic solvents (12.1%), polycyclic aromatic hydrocarbons (10.1%), and diesel engine emissions (8.3%). Racial and ethnic minoritized groups, persons with lower educational attainment, foreign-born noncitizens, and males were generally overrepresented in exposure to work-related chemical hazards. Conclusions. In the United States, marginalized sociodemographic groups are estimated to experience an inequitable burden to many chemical exposures because of occupational segregation. Data from this analysis can inform occupational and public health research, policy, and interventions aimed at reducing the burden of disease and health inequities in the United States. (Am J Public Health. 2024;114(1):57-67. https://doi.org/10.2105/AJPH.2023.307461).

Radiation exposure of urologists during endourological procedures: a systematic review.

INTRODUCTION: Ionizing radiation is used daily during endourological procedures. Despite the dangers of both deterministic and stochastic effects of radiation, there is a lack of knowledge and awareness among urologists. This study reviewed the literature to identify the radiation exposure (RE) of urologists during endourological procedures. METHODS: A literature search of the Medline, Web of Science, and Google Scholar databases was conducted to collect articles related to the radiation dose to urologists during endourological procedures. A total of 1966 articles were screened. 21 publications met the inclusion criteria using the PRIMA standards. RESULTS: Twenty-one studies were included, of which 14 were prospective. There was a large variation in the mean RE to the urologist between studies. PCNL had the highest RE to the urologist, especially in the prone position. RE to the eyes and hands was highest in prone PCNL, compared to supine PCNL. Wearing a thyroid shield and lead apron resulted in a reduction of RE ranging between 94.1 and 100%. Educational courses about the possible dangers of radiation decreased RE and increased awareness among endourologists. CONCLUSIONS: This is the first systematic review in the literature analyzing RE to urologists over a time period of more than four decades. Wearing protective garments such as lead glasses, a thyroid shield, and a lead apron are essential to protect the urologist from radiation. Educational courses on radiation should be encouraged to further reduce RE and increase awareness on the harmful effects of radiation, as the awareness of endourologists is currently very low.

Trends in the use of radiation protection and radiation exposure of European endourologists: a prospective trial from the EULIS-YAU Endourology Group.

INTRODUCTION: Due to the radiation exposure for the urology staff during endourology, our aim was to evaluate the trends of radiation protection in the operation room by endourologists from European centers and to estimate their annual radiation. METHODS: We conducted a multicenter study involving experienced endourologists from different European centers to evaluate whether the protection and threshold doses recommended by the International Commission on Radiation Protection (ICRP) were being followed. A 36-question survey was completed on the use of fluoroscopy and radiation protection. Annual prospective data from chest, extremities, and eye dosimeters were collected during a 4-year period (2017-2020). RESULTS: Ten endourologists participated. Most surgeons use lead aprons and thyroid shield (9/10 and 10/10), while leaded gloves and caps are rarely used (2/10 both). Six out of ten surgeons wear leaded glasses. There is widespread use of personal chest dosimeters under the apron (9/10), and only 5/10 use a wrist or ring dosimeter and 4 use an eye dosimeter. Two endourologists use the ALARA protocol. The use of ultrasound and fluoroscopy during PCNL puncture was reported by 8 surgeons. The mean number of PCNL and URS per year was 30.9 (SD 19.9) and 147 (SD 151.9). The mean chest radiation was 1.35 mSv per year and 0.007 mSv per procedure. Mean radiation exposure per year in the eyes and extremities was 1.63 and 11.5 mSv. CONCLUSIONS: Endourologists did not exceed the threshold doses for radiation exposure to the chest, extremities and lens. Furthermore, the ALARA protocol manages to reduce radiation exposure.

Recent developments in occupational asthma.

PURPOSE OF REVIEW: Occupational asthma (OA) is a complex condition that can be difficult to diagnose. The purpose of this review is to describe some recent findings regarding the epidemiology of OA, the occupational sensitizing agents, the prognosis of OA, and its primary prevention. RECENT FINDINGS: The risk of developing OA varies according to the geographic localization of the worker, the type of industry and the type of sensitizing agents. New findings have been reported for several known sensitizing agents, such as isocyanates, seafood & cleaning agents, and their related industries, such as hairdressing salons and schools. Moreover, a few new sensitizing agents, such as cannabis, have been identified in the past few years. The prognosis of OA seems worse than that of nonwork-related asthma. It is mainly determined by the duration and the level of exposure. Primary prevention is crucial to reduce the number of new cases of OA. Complete avoidance of exposure to the causal agent remains the optimal treatment of sensitizer-induced OA. SUMMARY: Improving our knowledge regarding OA and its causative agents is key to enable an early recognition of this condition and improve its prognosis. Further research is still needed to improve primary prevention.