Asbestos-related Lung Disease Research Articles

Reconstructing historical exposure to asbestos: the validation of 'educated guesses'.

In both the epidemiological and legal context, the causal attribution of asbestos-related lung diseases requires retrospective exposure assessment (REA). To assess the correlation between the retrospective assessment of occupational and anthropogenic environmental exposure to asbestos and its content in the lung tissue. Based on the available exposure information, a team of occupational physicians retrospectively assessed cumulative exposure to asbestos in 24 subjects who died of asbestos-related diseases. The asbestos lung content was analysed using analytical scanning electron microscope (SEM-EDS). The Log10 asbestos fibre count in the autoptic samples was predicted as a function of the Log10 estimated cumulative exposure using univariate regression analysis. The median count of asbestos fibres by grams of dry weight (ff/gdw) in the lung tissue was 81 339 (range 0-2 135 849.06); it was 287 144 (range 0-2 135 849.06) among the occupationally exposed, and 29 671 (range 0-116 891) among the subjects who only had anthropogenic environmental and/or household exposure. Amphiboles, and particularly amosite (52%) and crocidolite (43%), were detected in all the study subjects. Chrysotile was not detected in any of the samples. Overall, the retrospective estimate of lifetime cumulative exposure to asbestos showed a moderate correlation with the total asbestos fibre count in the autoptic lung, with the regression model explaining 38-55% of the total variance. Detailed information on occupational, environmental and household exposure circumstances would be indispensable for experienced industrial hygienists and/or occupational physicians to reliably assess past exposure to amphiboles or mixed types of asbestos.

Lung cancer and mesothelioma risks in a prospective cohort of workers with asbestos-related lung or pleural diseases.

Asbestos causes mesothelioma and lung cancer. In the European Union, asbestos was banned in 2005, but it is still in use in many other countries. The aim of this study was to estimate the lung cancer and mesothelioma incidence risk of men with benign asbestos-related lung or pleural diseases. Between 2008 and 2018, 2439 male participants of a German surveillance program for asbestos workers were included in the cohort. All participants had a recognized occupational asbestos-related disease of the pleura or lung. We estimated the mesothelioma and lung cancer risks by calculating standardized incidence ratios (SIR) with corresponding 95% confidence intervals (95% CI). We observed 64 incident lung cancer and 40 mesothelioma cases in the cohort. An SIR of 17.60 (95% CI: 12.57-23.96) was estimated for mesothelioma and 1.27 (95% CI: 0.98-1.62) for lung cancer. The presence of pleural plaques was associated with a strongly increased risk (SIR: 13.14; 95% CI: 8.51-19.40) for mesothelioma, but not for lung cancer (SIR: 1.05; 95% CI: 0.76-1.41). The highest lung-cancer risk (SIR: 2.56; 95% CI 1.10-5.04) was revealed for cohort members with less than 40 years since first asbestos exposure. Lung cancer risks by duration of asbestos exposure did not show a consistent time trend, but for time since last exposure a trend for mesothelioma was seen. Compared to the general population, we demonstrated an association between benign asbestos-related lung or pleural disease and mesothelioma risk in workers with a history of occupational asbestos exposure. Because lung-cancer risk is dominated by smoking habits, a possible effect of asbestos exposure may have been masked. Efforts should be made to ban production and use of asbestos worldwide and to establish safe handling rules of legacy asbestos.

The Chest CT Finding of Pleural Plaques and Asbestosis in Lung Cancer Patients: A Case Study

A sixty-eight years old man was referred to the hospital for evaluation of lung adenocarcinoma treatment. Chest computed tomography (CT) imaging showed lung nodule, pleural plaques, ground-glass opacity, and parenchymal bands related to asbestosis. Pleural plaques are the proxy of asbestos exposure, and asbestosis is lung parenchymal fibrosis caused by asbestos. The interview revealed that the patient had worked as an owner of a construction firm for more than 37 years. Construction workers are at high risk of getting asbestos-related diseases because some building materials have asbestos. This case study aimed to describe chest CT findings of asbestosis and pleural plaques that suggest the presence of asbestos exposure in a lung cancer case. This case showed the pivotal role of chest CT to define asbestos-related lung diseases and a structured interview to obtain past asbestos exposure.

Inhalation Toxicity of Talc.

Respirable talc powder (RTP) is a complex mineral mixture of talc along with accessory minerals, including tremolite, anthophyllite, quartz, magnesite, dolomite, antigorite, lizardite, and chlorite. The industrial mining, milling, and processing of talc ore is associated with elevated incidences of fibrotic and neoplastic diseases, which are also seen among workers exposed to RTP in secondary industries and individuals using processed cosmetic talc for personal use. There is controversial evidence of a link between the talc-induced lung diseases and a potential contamination with asbestos fibers. This controversy is fueled by inadequate exposure data and the complex mineralogy and terminology of the accessory minerals. Talc aerosols exhibit a wide range of mineral habits, including particulates and fibrous structures that have dimensional and compositional characteristics related to the development of asbestos-related lung disease. The inhalation toxicology of RTP is based on the analysis of occupational hygiene and animal inhalation studies conducted between the 1940s and the 1990s and more recent mechanistic studies conducted both in vivo and in vitro. The review of talc toxicity studies reveals that the occupational studies provide only equivocal links between any of the components of the aerosols and the development of pulmonary cancer; however, there is substantial evidence of an association between the aerosols and pleural and pulmonary fibrosis and the development of nonmalignant respiratory disease. The animal inhalation and implantation studies appear to be less than optimal, which also appears to be true for the in vivo and in vitro studies. The mechanistic studies have identified the key pathogenic characteristics of asbestos to be long and thin fibers that are durable in lung tissues and fluids. Talc toxicity studies show that talc particles and fibers are durable and can remain in the lung for up to 40 years after the end of exposure. This extended tissue residence is considered to constitute a continuing tissue exposure that is capable of inducing the documented inflammatory and proliferative response. There is less consensus as to whether there is a threshold fiber length effect, as long, thin fibers (>5 μm) form only a small fraction of talc aerosols and the possible role of fibers >5 μm in the translocation from the lung to the pleura and their association with pleural fibrotic and carcinogenic lesions. Long, thin fibers are preferentially deposited in hot spots in the lung, such as airway bifurcations, areas typically associated with the development of lung cancer. The platy structures typical of talc can form oblate structures behaving more as fibers in the air stream, and these have also been shown to deposit preferentially in such locations. The review of the inhalation toxicity of talc provides a plausible explanation for the carcinogenic potential of RTP.

Imaging of asbestos-related lung and pleural diseases as an endemic exposure in Egypt

BackgroundAsbestos refers to a group of naturally occurring silicate minerals which have been traditionally used in building materials and household products. Inhalation of asbestos fibers, however, has been associated with adverse health outcomes, with the disease manifestations principally affecting the thorax. The aim of our study is to detect and evaluate the different radiological patterns of asbestos-related lung and pleural disease and its complicationsResultsMDCT examination was able to assess and distinguish asbestosis as well as asbestos-related lung and pleural disease besides detection of any associated complications.ConclusionThis study demonstrates that while reporting of malignant asbestos-related pleural disease is adequate, there is room for improvement in the reporting of more benign disease.

Distribution of Asbestos Enterprises and Asbestosis Cases - China, 1997-2019.

What is already known on this topic?Asbestos is classified as a Class I Carcinogen by the International Agency for Research on Cancer (IARC) because exposure causes mesothelioma and lung cancer in addition to asbestosis and plaques. So far, asbestos has been banned in 67 countries, but chrysotile, a commonly encountered form of asbestos, is still widely used in China and most developing countries. Most asbestos-caused cancers are not reported, recorded, and compensated in many countries.What is added by this report?Enterprises manufacturing asbestos products have been migrating from economically developed Eastern China to relatively underdeveloped central and western regions between 2010 and 2019. Asbestosis cases reported in Tianjin, Beijing, Shandong, Xinjiang, Gansu, Qinghai, and Sichuan accounted for a large proportion of the total cases in China, which was inconsistent with the distribution of asbestos-related enterprises (AREs). The reported asbestosis cases versus total pneumoconiosis cases declined from 2.81% to 0.39% from 2006–2017, and this proportion reached 0.69% in 2018.What are the implications for public health practice?Robust occupational and environmental health assessments and reporting are needed to define the epidemiology of asbestos-related lung diseases, and management of using asbestos and existing products containing asbestos need strengthening and follow-up. Enterprises should be encouraged to use safer substitutes and gradually ban asbestos materials in China.

Cytological analysis of bronchoalveolar lavage fluid in asbestos-exposed workers.

Background:Asbestos-related lung diseases are a group of heterogeneous disorders with different pathogenesis and prognosis. Very few studies investigated the BALF cell profile of asbestos exposed workers. The existence of a relationship between bronchoalveolar lavage fluid (BALF) cellular pattern and specific diagnosis and/or asbestos exposure biomarkers would allow the identification of effect biomarkers useful in the follow up of asbestos-exposed workers and in the diagnosis of asbestos-related diseases.Objectives:To assess BALF cell profile in formerly asbestos-exposed workers and its relationship with asbestos fibre (amphibole and chrysotile) and asbestos body (AB) concentrations.Methods:113 male workers formerly exposed to asbestos underwent bronchoscopy with bronchoalveolar lavage and were retrospectively enrolled. 35 of them were affected by pleural plaques and 10 were affected by asbestosis. Pulmonary functional tests (PFT), BALF cellular pattern, BALF mineralogical analysis with asbestos fibres and AB counting were performed in each patient. A statistical analysis with a multivariate linear regression model was adopted.Results:From the statistical analysis of data a direct correlation between pack-years and BALF macrophages was found. Inversely correlation between pack-years and BALF lymphocytes was detected. There was not relationship among BALF cellular pattern, PFT values, specific diagnosis, BALF AB count or BALF asbestos fibre concentration.Discussion:BALF cellular pattern does not seem to be related to asbestos exposure biomarkers like AB and asbestos fibre concentration in BALF. Instead, smoke habit can induce an increase in BALF macrophages and a decrease of BALF lymphocytes count.

Prevalence of Asbestos-Related Disease Among Workers in Sri Lanka.

Background:Asbestos products are manufactured and used in Sri Lanka in the construction and automobile industries.Objective:To determine radiologically if exposure to asbestos caused lung disease among workers handling asbestos products, and to generate data in Sri Lanka where no such data exist due to poor reporting and a poor surveillance system.Methods:Following ethics approval and written consent plain chest X-rays and exposure data were obtained in 230 workers in asbestos manufacturing, building construction, building demolition, tsunami debris cleanup, and other trades. The assumption was that all exposed workers were exposed to chrysotile. Participants were from provinces with asbestos factories, and where tsunami cleanup had occurred.Findings and Conclusions:Radiological findings of the 230 participants showed lung fibrosis in 7% (16 cases), and other non-asbestos-related lung conditions. Of the 16 fibrosis cases, none were in manufacturing workers, one in a construction worker, six in tsunami workers, six in demolition workers, and three cases in others. Globally, Sri Lanka has one of the highest consumptions of chrysotile asbestos per capita. This first known study documenting asbestos disease in Sri Lanka is clearly a limited, self-selected group of workers studied with obvious limitations. The prevalence of asbestos-related lung disease among tsunami and demolition worker indicates that a risk exists for asbestos material already in use in Sri Lanka. Hence a significant concern is the safety of asbestos demolition workers and cleanup workers exposed to asbestos debris from major natural disasters such as hurricanes, tornados, typhoons, and tsunamis.

Association between increased small airway obstruction and asbestos exposure in patients with asbestosis.

Asbestos exposure may cause asbestos-related lung diseases including asbestosis, pleural abnormalities and malignancies. The role of asbestos exposure in the development of small airway obstruction remains controversial. Anatomic and physiologic small airway abnormalities may develop as part of the pathophysiologic process of asbestosis. We hypothesized that inhalation of asbestos may induce small airway defects in addition to asbestosis and pleural abnormalities. In total, 281 patients with newly diagnosed asbestosis were evaluated. Clinical data were collected from the patients' medical charts. The patients were classified into various stages according to their chest X-ray findings using the International Labour Organization classification. Pulmonary function was evaluated by plethysmography and the forced oscillation technique. Expiratory flow, including the predicted values of the maximum expiratory flow between 25% and 50% of the forced vital capacity (MEF25-50 ), was significantly lower in the different stages of asbestosis. Accordingly, the predicted percentage of R5 -R20 was significantly higher with increasing stages of asbestosis. Furthermore, the duration of exposure to asbestos was significantly associated with the forced expiratory volume in the first second (FEV1 )/forced vital capacity (FVC) ratio and the predicted percentage of MEF25 or MEF50 according to the regression analysis in non-smoking patients with asbestosis. The predicted percentage of FEV1 or the FEV1 /FVC ratio was significantly lower and the predicted percentage of R5 -R20 was significantly higher in smokers than non-smokers. The patients with asbestosis have small airway obstructive defects that are significantly associated with asbestos exposure.

Chest ultrasonography in health surveillance of asbestos-related lung diseases.

Exposure to asbestos fibers can lead to different lung diseases, such as pleural thickening and effusion, asbestosis, mesothelioma, and lung cancer. These diseases are expected to peak in the next few years. The aim of the study was to validate ultrasonography (US) as a diagnostic tool in the management of lung diseases in subjects with a history of occupational exposure to asbestos. Fifty-nine retired male workers previously exposed to asbestos were enrolled in the study. Chest US was performed in all the subjects. The US operator was blinded to earlier performed computed tomography (CT) scan reports and images. The sonographic pathological findings were pleural thickening (with or without calcifications), peripheral lung consolidation, and focal sonographic interstitial syndrome and diffuse pneumogenic sonographic interstitial syndrome (pulmonary asbestosis). Significant US findings were recorded, stored, and subsequently compared with CT scans. With some patients falling into more than one category, on CT scan, pleural thickening was reported in 33 cases (56%, 26 with calcifications), focal interstitial peripheral alterations in 23 (39%), asbestosis in 6 (10%), and peripheral lung consolidation in 13 cases (22%). Comparing each pathological condition to CT scan reports, US findings had high levels of sensitivity, specificity, positive, and negative predictive values. US did not prove effective for the detection of central lung nodules or diaphragmatic pleural thickenings. Chest US was considered to be the best technique to detect minimal pleural effusions (six subjects, 10%). Chest US might be considered an additional tool to follow up subjects occupationally exposed to asbestos who have already undergone CT scan examination and whose pathology is detectable by US as well.

Action needed to prevent increase of asbestos-related lung diseases in Asia

Action needed to prevent increase of asbestos-related lung diseases in Asia

Asbestos in Asia.

Asbestos is a global killer. Despite lessons learned in the developed world on the use of asbestos and its hazardous pulmonary consequences, its use continues to increase in Asia. Although some countries such as Japan, Korea and Singapore have curtailed the use of this mineral, there are numerous countries in Asia that continue to mine, import and use this fibre, particularly China, which is one of the largest consumers in the world. Numerous factors ranging from political and economic to the lack of understanding of asbestos and the management of asbestos-related lung disease are keys to this observed trend. Awareness of these factors combined with early intervention may prevent the predicted Asian 'tsunami' of asbestos diseases.

In vivo Optical Coherence Tomography Imaging of the Mesothelium Using Developed Window Models

The mesothelium is an essential lining for maintaining the normal homeostasis of the closed body cavity and a central component of pathophysiologic processes. The mesothelium has been known as the end target for asbestos which induces asbestos-related lung diseases. Malignant mesothelioma (MM) is a rare and fatal neoplasm predominantly due to asbestos exposure. Adaptation of an advanced and reliable technology is necessary for early detection of MM because it is difficult to diagnose this disease in its early stages. Optical coherence tomography (OCT) provides cross-sectional images of micro-tissue structures with a resolution of <TEX>$2-10{\mu}m$</TEX> that can image the mesothelium with a thickness of <TEX>${\sim}100{\mu}m$</TEX> and, therefore, enable investigation of early development of MM. The mesothelium is typically located at the pleura and tunica vaginalis of the scrotum. In this study, we developed animal window models in the above two anatomical sites to visualize mesothelial layers within the mesothelium. OCT images at the two locations were also acquired.

Signals in asbestos related diseases in human breath - preliminary results

Several diseases occur due to asbestos exposure. Until today, asbestos predicted mortality and morbidity will increase because of the long latency period. Actually, the methods to investigate asbestos related disease are mostly invasive. Therefore, the aim of the present paper was to investigate, whether signals in human breath could be correlated to Asbestos related lung diseases using a multi-capillary column (MCC) connected to an ion mobility spectrometer (IMS) as non-invasive method. Here, the breath samples of 10 mL of 25 patients suffering from asbestos related diseases. This group includes patients with asbestos related pleural thickening with and without pulmonary fibrosis. Twelve healthy persons constitute the control group and the breath samples are compared with those of the BK4103 patients. In total 83 peaks are found in the IMS-Chromatogram. A discrimination was possible with p-values <0.001 for two peaks (99.9 %), <0.01 (99 %) for 5 peaks and <0.05 (95 %) for 17 peaks. The most discrimination peaks alpha pinene and 4-ethyltoluol were identified among some others with lower p-values. The corresponding Box-and-Whisker-Plots comparing both groups are presented. In addition, a decision tree including all peaks was created that shows a differentiation with alpha pinene between BK4103 (pleural plaques group) and the control group. In addition, the sensitivity was calculated to 96 %, specificity was 50 %, positive and negative predictive values were 80 % and 86 %. Ion mobility spectrometry was introduced as non-invasive method to separate both groups Asbestos related and healthy. Naturally, the findings need further confirmation on larger population groups, but encourage further investigations, too.

P207 Reporting of asbestos related lung disease to HM Coroner: A retrospective analysis

BackgroundAsbestos related lung disease consists of a spectrum of disorders, ranging from benign pleural plaques to mesothelioma. In patients with a history of asbestos exposure, radiological imaging can be used...

Incidence of asbestosis and other benign lung diseases: Spain, 1962-2010

We lack in Spain of a full description of the diseases caused by asbestos since its inclusion in the list of occupational diseases 1961. The aim of this study is to know the incidence of asbestosis and other asbestos-related benign lung diseases, which were recognized as occupational diseases by the Spanish Social Security system between 1962 and 2010. Cases were obtained from Reports of the National Insurance Institute (1962 to 1975), from Employment Ministry Statistics and Reports of the Work Health and Safety Department (1976 to 1981), and from the Employment Statistics Yearbooks (from 1982). Specific rates were obtained by economic activity and occupation. We represent temporal trends in the number of the diseases under study and described their geographic distribution by provinces. Between 1963 and 2010, 815 cases of asbestosis and 46 cases of fibrous pleural or pericardial disease were recognized. Since 1990 until 2001 Fiber-cement sector accumulated 189 cases of asbestosis, Shipbuilding sector 173, Construction sector 49 and Metallurgy 35. By occupation, fixed machinery operators had 114 cases; in molders, welders, sheet metal workers and fitters 88 cases; and painters, plumbers and pipe fitters 59 cases. The autonomous communities with the highest number of cases were Valencia (106), Galicia (86), Andalusia (82), Catalonia (75), Madrid (58), and the Basque Country (41). Incidence rates and the time trend of professional asbestosis in Spain may be demonstrating the underreporting of the occupational origin of these diseases in our country. The most affected sectors were that of the fiber-cement and the naval one and the highest incidence was given in the Valencian Community.

Libby vermiculite exposure and risk of developing asbestos-related lung and pleural diseases

The vermiculite ore formerly mined in Libby, Montana, contains asbestiform amphibole fibers of winchite, richterite, and tremolite asbestos. Because of the public health impact of widespread occupational and nonoccupational exposure to amphiboles in Libby vermiculite, numerous related studies have been published in recent years. Here we review current research related to this issue. Excess morbidity and mortality classically associated with asbestos exposure have been well documented among persons exposed to Libby vermiculite. Excess morbidity and mortality have likewise been documented among persons with only nonoccupational exposure. A strong exposure-response relationship exists for many malignant and nonmalignant outcomes and the most common outcome, pleural plaques, may occur at low lifetime cumulative exposures. The public health situation related to Libby, Montana, has led to huge investments in public health actions and research. The resulting studies have added much to the body of knowledge concerning health effects of exposures to Libby amphibole fibers specifically and asbestos exposure in general.

Asbestos-related Lung Disease

In this work, we describe both benign and malignant asbestos-related diseases and provide an updated review of recent advances in the field. It has long been appreciated that the inhalation of asbestos fibers causes several well-described respiratory diseases including pleural plaques, diffuse pleural thickening, asbestosis, lung cancer, and malignant pleural mesothelioma (MPM). However, despite this knowledge and stricter industrial controls, the incidence of these diseases continues to increase in many parts of the world. In fact, despite the introduction of strict limits early in the 20th century, the mortality rate due to MPM is still increasing in industrialized countries such as the United Kingdom and Australia. In this update we provide an overview of each disease entity while concentrating on the role that newer imaging techniques, including high-resolution computed tomography, magnetic resonance imaging, and positron emission tomography /computed tomography, play in the diagnosis of asbestos-related pleural and parenchymal diseases. As the incidence of MPM continues to increase in many parts of the world, this review also focuses on new approaches to the diagnosis and treatment of this devastating condition. A description of the potential use and limitations of biomarkers in the diagnosis and monitoring of the disease is included along with recent trial data examining novel vaccine-based biological therapies.

Asbestos-the Silent Killer: a review of screening and diagnostic imaging of asbestos related lung disease

An epidemic of asbestos related lung (ARLD) disease stares the developed countries in the face. However, these countries have lately banned the use of asbestos. Nevertheless, Western countries have no qualms of selling asbestos to poor countries that have no credible health safety regulations in the work place. Epidemiologic studies predicted a decline in incidence of ARLD in the US after the year 2000, with a peak incidence in the UK in 2020. Lung cancer (LC) develops in up to 25% of asbestos workers. In exposed nonsmokers, there is 5-fold increase. In exposed individuals, smoking further increases the risk of bronchogenic carcinoma by 80-90-fold. However the silent killer, asbestos is still active in developing countries and is likely to remains so in decades to come. In the Middle East, immigrant workers still work in asbestos environment. Saudi Arabia is the only major country in the Middle East that has banned asbestos, but workers continue to be at risk due to maintenance work on buildings built before the ban. As asbestos related lung disease remains silent in many and has a long latent period, the only way of detecting these diseases early is by diligence being aware of the patient&amp;rsquo;s occupational history and affective imaging. Presently there is no credible screening for ARLD. Here we review imaging studies in ARLD to increase awareness of this potentially lethal disease. Whereas diagnosis of ARLD is a matter for compensation in the developed countries it is a matter of survival in the developing world where industrialization has just begun and may take decades to remove the threat of asbestos. In this review we will discuss the clinical, radiologic, and pathologic features of ARLD.

Asbestos-the Silent Killer: a review of screening and diagnostic imaging of asbestos related lung disease

An epidemic of asbestos related lung (ARLD) disease stares the developed countries in the face. However, these countries have lately banned the use of asbestos. Nevertheless, Western countries have no qualms of selling asbestos to poor countries that have no credible health safety regulations in the work place. Epidemiologic studies predicted a decline in incidence of ARLD in the US after the year 2000, with a peak incidence in the UK in 2020. Lung cancer (LC) develops in up to 25% of asbestos workers. In exposed nonsmokers, there is 5-fold increase. In exposed individuals, smoking further increases the risk of bronchogenic carcinoma by 80-90-fold. However the silent killer, asbestos is still active in developing countries and is likely to remains so in decades to come. In the Middle East, immigrant workers still work in asbestos environment. Saudi Arabia is the only major country in the Middle East that has banned asbestos, but workers continue to be at risk due to maintenance work on buildings built before the ban. As asbestos related lung disease remains silent in many and has a long latent period, the only way of detecting these diseases early is by diligence being aware of the patient’s occupational history and affective imaging. Presently there is no credible screening for ARLD. Here we review imaging studies in ARLD to increase awareness of this potentially lethal disease. Whereas diagnosis of ARLD is a matter for compensation in the developed countries it is a matter of survival in the developing world where industrialization has just begun and may take decades to remove the threat of asbestos. In this review we will discuss the clinical, radiologic, and pathologic features of ARLD.