Ecological association between asbestos-related diseases and historical asbestos consumption: an international analysis

The characteristics of asbestos-related disease claims made to the Korea Workers' Compensation and Welfare Service (KCOMWEL) from 2011 to 2015

Background

This study aimed to enhance understanding of the epidemiologic characteristics of asbestos-related diseases, and to provide information that could inform policy-making aimed at prevention and compensation for occupational asbestos exposure, through analyzing asbestos-related occupational disease claims to Korea Workers’ Compensation and Welfare Service from 2011 to 2015.

Methods

We analyzed 113 workers who filed medical care claims or survivor benefits for asbestos exposure and occupational-related disease from 2011 to 2015. Among these claims, we selected approved workers’ compensation claims relating to malignant mesothelioma and lung cancer, and analyzed the general characteristics, exposure characteristics, pathological characteristics, and occupation and industry distribution.

Results

Malignant mesothelioma and lung cancer occurred predominantly in males at 89.7 and 94%, respectively. The mean age at the time of diagnosis for malignant mesothelioma and lung cancer was 59.5 and 59.7 years, respectively, while the latency period for malignant mesothelioma and lung cancer was 34.1 and 33.1 years, respectively. The companies involving exposed workers were most commonly situated within the Busan-Ulsan-Gyeongnam region. Histology results for lung cancer indicated adenocarcinoma as the most common form, accounting for approximately one half of all claims, followed by squamous cell carcinoma, and small cell lung cancer. The most common occupation type was construction in respect of malignant mesothelioma, and shipbuilding in respect of lung cancer.

Conclusions

Considering the long latency period of asbestos and that the peak period of asbestos use in Korea was throughout the mid-1990s, damage due to asbestos-related diseases is expected to show a continued long-term increase. Few studies providing an epidemiologic analysis of asbestos-related diseases are available; therefore, this study may provide baseline data to assist in predicting and preparing for future harm due to asbestos exposure.

Trial registration

DUIH 2018–02–004-001. Registered 28 Februrary 2018.

Current management strategies for peritoneal mesothelioma

Mesothelioma of the peritoneum is a distinct entity that requires multidisciplinary care to improve oncological outcomes. In this article, we review the current management strategies discussed at the PSOGI meeting in Washington DC 2016 and provide evidence based recommendations for diagnosis and management of this disease.

Trends and the Economic Effect of Asbestos Bans and Decline in Asbestos Consumption and Production Worldwide

Although some countries have reduced asbestos consumption and instituted bans, other countries continue to produce and consume asbestos even as asbestos-related deaths mount and the associated societal costs are high. Asbestos production and consumption has declined globally; the number of bans has increased; and the speed at which countries have tapered off consumption has increased. Using country-level data, we study the economic impact of historical changes in the production and use of asbestos. We compare changes in gross domestic product (GDP) following the enactment of asbestos bans. We do not find any significant effect on GDP following an asbestos ban. In a regional case study, we compare changes in GDP and employment with changes in asbestos production. Regional-level data revealed a temporary employment decline at the local level that was then reversed.

Asbestos-Related Disorders in Germany: Background, Politics, Incidence, Diagnostics and Compensation

There was some limited use of asbestos at end of the 19th century in industrialized countries including Germany, but its consumption dramatically increased after World War II. The increase in use and exposure was followed by the discovery of high numbers of asbestos-related diseases with a mean latency period of about 38 years in Germany. The strong socio-political pressure from the asbestos industry, its affiliated scientists and physicians has successfully hindered regulatory measures and an asbestos ban for many years; a restrictive stance that is still being unravelled in compensation litigation. This national experience is compared with the situation in other industrialized countries and against the backdrop of the constant efforts of the WHO to eliminate asbestos-related diseases worldwide.

Asbestos Consumption in Mongolia: 1996-2014

Asbestos is still used in Mongolia in the energy and construction sectors, among others. However, limited data is available on asbestos consumption and asbestos-related disease in Mongolia. The purpose of this paper is to present the available information on the importation of asbestos into Mongolia. We used data on annual asbestos imports between 1996 and 2014 from Mongolian Customs Statistics and the National Council on Toxic and Hazardous Substances Affairs. The uses of this material are also presented with respect to chrysotile alone. Most asbestos is used for construction. Mongolia started using asbestos in the energy and construction industries as thermal insulation in 1961. Asbestos is still allowed for use in Mongolia under the Law on Toxic and Hazards Substances. There are no asbestos mines in Mongolia, and the manufacture of asbestos-containing materials does not take place there. Thus, asbestos is mainly imported from China and Russia. Mongolia used 44,422 metric tons of asbestos-containing materials between 1996 and 2014. In Mongolia, with the current use of asbestos, there will be a continuing risk of developing asbestos-related diseases from past use, and proper oversight of asbestos-involving activities and the safe removal and disposal of asbestos must be considered.

The Global Health Dimensions of Asbestos and Asbestos-Related Diseases

The Collegium Ramazzini (CR) reaffirms its long-standing position that responsible public health action is to ban all extraction and use of asbestos, including chrysotile. This current statement updates earlier statements by the CR with a focus on global health dimensions of asbestos and asbestos-related diseases (ARDs). The ARD epidemic will likely not peak for at least a decade in most industrialized countries and for several decades in industrializing countries. Asbestos and ARDs will continue to present challenges in the arena of occupational medicine and public health, as well as in clinical research and practice, and have thus emerged as a global health issue. Industrialized countries that have already gone through the transition to an asbestos ban have learned lessons and acquired know-how and capacity that could be of great value if deployed in industrializing countries embarking on the transition. The accumulated wealth of experience and technologies in industrialized countries should thus be shared internationally through global campaigns to eliminate ARDs.

Capture of mesothelioma cells with 'universal' CTC-chip

Malignant mesothelioma (MM) is a highly aggressive malignant tumor, predominantly associated with job-related exposure to asbestos. Development of effective and non-invasive modalities for diagnosis is an important issue in occupational medicine. Circulating tumor cells (CTCs), which are tumor cells that are shed from primary tumors and circulate in the peripheral blood, may be detected at an earlier stage than malignant tumors, and detection of CTCs may provide a novel insight into the diagnosis of MM. In a previous study evaluating clinical utility of CTCs, detected with a widely used system 'CellSearch', the authors indicated a significant however insufficient capability in the diagnosis of MM, suggesting need for a more sensitive system. Accordingly, the authors developed a novel microfluidic system to capture CTCs (CTC-chip), and demonstrated that the CTC-chip effectively captured MM cells (ACC-MESO-4) spiked in the blood by conjugating an anti-podoplanin antibody. The results of the present study demonstrated that the CTC-chip coated with the anti-podoplanin antibody captured another MM cell (ACC-MESO-1). However, the capture efficiencies were lower than those for ACC-MESO-4. In addition, an anti-mesothelin antibody was used to capture CTCs, however the CTC-chip coated with the anti-mesothelin antibody failed to effectively capture MM cells, possibly due to low mesothelin expression. Overall, the CTC-chip may capture specific types of CTCs by conjugating any antibody against an antigen expressed on CTCs, and may be a useful system for the diagnosis of malignant tumors, including MM.

Circulating complement component 4d (C4d) correlates with tumor volume, chemotherapeutic response and survival in patients with malignant pleural mesothelioma

Only limited information is available on the role of complement activation in malignant pleural mesothelioma (MPM). Thus, we investigated the circulating and tissue levels of the complement component 4d (C4d) in MPM. Plasma samples from 55 MPM patients, 21 healthy volunteers (HV) and 14 patients with non-malignant pleural diseases (NMPD) were measured by ELISA for C4d levels. Tissue specimens from 32 patients were analyzed by C4d immunohistochemistry. Tumor volumetry was measured in 20 patients. We found no C4d labeling on tumor cells, but on ectopic lymphoid structures within the tumor stroma. Plasma C4d levels did not significantly differ between MPM, HV or NMPD. Late-stage MPM patients had higher plasma C4d levels compared to early-stage (p = 0.079). High circulating C4d was associated with a higher tumor volume (p = 0.047). Plasma C4d levels following induction chemotherapy were significantly higher in patients with stable/progressive disease compared to those with partial/major response (p = 0.005). Strikingly, patients with low C4d levels at diagnosis had a significantly better overall survival, confirmed in a multivariate cox regression model (hazard ratio 0.263, p = 0.01). Our findings suggest that circulating plasma C4d is a promising new prognostic biomarker in patients with MPM and, moreover, helps to select patients for surgery following induction chemotherapy.

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

BACKGROUND

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.

METHODS

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.

RESULTS

Expiratory flow, including the predicted values of the maximum expiratory flow between 25% and 50% of the forced vital capacity (MEF_25-50 ), 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.

CONCLUSIONS

The patients with asbestosis have small airway obstructive defects that are significantly associated with asbestos exposure.

Transnational Dynamics Amid Poor Regulations: Taiwan's Asbestos Ban Actions and Experiences

This article describes the history of the asbestos use regulation process in Taiwan and the associated factors leading to its total ban in 2018. Despite the long history of asbestos mining and manufacturing since the Japanese colonial period, attempts to understand the impact of asbestos on the health of the population and to control its use did not emerge until the early 1980s. We attempted to investigate the driving forces and obstructions involved in asbestos regulations by reviewing available public sources and scientific journal articles and conducting interviews with key propagators of the asbestos regulation and ban. Correlation between asbestos exposure and asbestos-related diseases has already been established; however, authorities have been unable to effectively regulate the extensive application of asbestos in various light industries that support economic growth since the 1960s. More stringent regulations on asbestos use in industries and an eventual ban were caused indirectly by appeals made by visionary scholars and healthcare professionals but also due to the subsidence of asbestos-related industries. With the elucidation of factors that affect asbestos regulation and ban, a thorough long-term healthcare plan for the neglected victims of asbestos-related diseases and upstream measures for policy change must be developed.

Estimation of the global burden of mesothelioma deaths from incomplete national mortality data

Background

Mesothelioma is increasingly recognised as a global health issue and the assessment of its global burden is warranted.

Objectives

To descriptively analyse national mortality data and to use reported and estimated data to calculate the global burden of mesothelioma deaths.

Methods

For the study period of 1994 to 2014, we grouped 230 countries into 59 countries with quality mesothelioma mortality data suitable to be used for reference rates, 45 countries with poor quality data and 126 countries with no data, based on the availability of data in the WHO Mortality Database. To estimate global deaths, we extrapolated the gender-specific and age-specific mortality rates of the countries with quality data to all other countries.

Results

The global numbers and rates of mesothelioma deaths have increased over time. The 59 countries with quality data recorded 15 011 mesothelioma deaths per year over the 3 most recent years with available data (equivalent to 9.9 deaths per million per year). From these reference data, we extrapolated the global mesothelioma deaths to be 38 400 per year, based on extrapolations for asbestos use.

Conclusions

Although the validity of our extrapolation method depends on the adequate identification of quality mesothelioma data and appropriate adjustment for other variables, our estimates can be updated, refined and verified because they are based on commonly accessible data and are derived using a straightforward algorithm. Our estimates are within the range of previously reported values but higher than the most recently reported values.

Estimated future incidence of malignant mesothelioma in South Korea: Projection from 2014 to 2033

Malignant mesothelioma is a malignant tumor on the pleura or the peritoneum caused mostly by asbestos. Although asbestos is not currently used in South Korea, the incidence of mesothelioma is increasing due to its long latent period. This study predicted the incidence of malignant mesothelioma in South Korea over the next 20 years using an age-period-cohort (APC) model. Data regarding mesothelioma incidence from 1994–2013 were acquired from the Korea Central Cancer Registry (KCCR). Demographic data, including prospective resident data, were acquired from the Korean Statistical Information Service (KOSIS) for 1994–2033. An APC model with Møller’s power-link function was utilized to predict the incidence of mesothelioma. It was predicted that 2,380 and 1,199 new cases of mesothelioma in men and women, respectively, would occur over the next 20 years. For both sexes, the mesothelioma incidence rate was predicted to be greater in 2029–2033 compared to that in 2009–2013 (men, 0.282 vs 0.563; women, 0.155 vs 0.217). For men, the age-standardized incidence rate was predicted to be slightly greater in 2029–2033 relative to the rate in 2009–2013 (0.228 vs 0.235), while the age-standardized incidence rate in women decreased within the same timeframe (0.113 vs 0.109). The changes in mesothelioma incidence were mostly caused by changes in the population structure due to aging and not by changes in the mesothelioma risk ratio. The results of this study project a continuous increase in mesothelioma incidence in South Korea over the next 20 years. Although the projected increase in mesothelioma incidence was not related to an increase in the mesothelioma risk ratio, continuous preventive efforts are necessary to reduce the exposure to asbestos and prevent the trend from worsening.

Compensation for Asbestos-Related Diseases in Japan: Utilization of Standard Classifications of Industry and Occupations

Background:

Asbestos-related diseases (ARD) are occupational hazards with high mortality rates. To identify asbestos exposure by previous occupation is the main issue for ARD compensation for workers. This study aimed to identify risk groups by applying standard classifications of industries and occupations to a national database of compensated ARD victims in Japan.

Methods:

We identified occupations that carry a risk of asbestos exposure according to the International Standard Industrial Classification of All Economic Activities (ISIC). ARD compensation data from Japan between 2006 and 2013 were retrieved. Each compensated worker was classified by job section and group according to the ISIC code. Risk ratios for compensation were calculated according to the percentage of workers compensated because of ARD in each ISIC category.

Results:

In total, there were 6,916 workers with ARD who received compensation in Japan between 2008 and 2013. ISIC classification section F (construction) had the highest compensated risk ratio of 6.3. Section C (manufacturing) and section F (construction) had the largest number of compensated workers (2,868 and 3,463, respectively). In the manufacturing section C, 9 out of 13 divisions had a risk ratio of more than 1. For ISIC divisions in the construction section, construction of buildings (division 41) had the highest number of workers registering claims (2,504).

Conclusion:

ISIC classification of occupations that are at risk of developing ARD can be used to identify the actual risk of workers’ compensation at the national level.

Lung function not affected by asbestos exposure in workers with normal Computed Tomography scan

BACKGROUND

It has been suggested that asbestos exposure affects lung function, even in the absence of asbestos-related pulmonary interstitial or pleural changes or emphysema.

METHODS

We analyzed associations between well-known asbestos-related risk factors, such as individual cumulative asbestos exposure, and key lung function parameters in formerly asbestos-exposed power industry workers (N = 207) with normal CT scans. For this, we excluded participants with emphysema, fibrosis, pleural changes, or any combination of these.

RESULTS

The lung function parameters of FVC, FEV1, DLCO/VA, and airway resistance were significantly associated with the burden of smoking, BMI and years since end of exposure (only DLCO/VA). However, they were not affected by factors directly related to amount (eg, cumulative exposure) or duration of asbestos exposure.

CONCLUSIONS

Our results confirm the well-known correlation between lung function, smoking habits, and BMI. However, we found no significant association between lung function and asbestos exposure.

Pathway deviation-based biomarker and multi-effect target identification in asbestos-related squamous cell carcinoma of the lung

Asbestos-related lung carcinoma is one of the most devastating occupational cancers, and effective techniques for early diagnosis are still lacking. In the present study, a systematic approach was applied to detect a potential biomarker for asbestos-related lung cancer (ARLC); in particular asbestos-related squamous cell carcinoma (ARLC-SCC). Microarray data (GSE23822) were retrieved from the Gene Expression Omnibus database, including 26 ARLC-SCCs and 30 non-asbestos-related squamous cell lung carcinomas (NARLC-SCCs). Differentially expressed genes (DEGs) were identified by the limma package, and then a protein-protein interaction (PPI) network was constructed according to the BioGRID and HPRD databases. A novel scoring approach integrating an expression deviation score and network degree of the gene was then proposed to weight the DEGs. Subsequently, the important genes were uploaded to DAVID for pathway enrichment analysis. Pathway correlation analysis was carried out using Spearman's rank correlation coefficient of the pathscore. In total, 1,333 DEGs, 391 upregulated and 942 downregulated, were obtained between the ARLC-SCCs and NARLC-SCCs. A total of 524 important genes for ARLC-SCC were significantly enriched in 22 KEGG pathways. Correlation analysis of these pathways showed that the pathway of SNARE interactions in vesicular transport was significantly correlated with 12 other pathways. Additionally, obvious correlations were found between multiple pathways by sharing cross-talk genes (EGFR, PRKX, PDGFB, PIK3R3, SLK, IGF1, CDC42 and PRKCA). On the whole, our data demonstrate that 8 cross-talk genes were found to bridge multiple ARLC-SCC-specific pathways, which may be used as candidate biomarkers and potential multi-effect targets. As these genes are involved in multiple pathways, it is possible that drugs targeting these genes may thus be able to influence multiple pathways simultaneously.

Role of postoperative radiotherapy in the management of malignant pleural mesothelioma : A propensity score matching of the SEER database

INTRODUCTION

This study assessed the prognostic impact of postoperative radiotherapy in patients with surgically resected malignant pleural mesothelioma (MPM).

METHODS

MPM patients diagnosed between 2000 and 2013 were identified from the SEER (Surveillance, Epidemiology, and End Results) database. A propensity-matched analysis was performed considering baseline characteristics (age, gender, race, histology, TNM stage, and type of surgery).

RESULTS

A total of 2166 patients were identified. The median age was 60 years (range 25-85 years), and 469 patients received postoperative radiotherapy. Both before and after propensity score matching, overall survival (P < 0.0001 and P = 0.012, respectively) was better in the postoperative radiotherapy group. When the overall survival was stratified by histology, postoperative radiotherapy did not improve the survival in sarcomatoid histology patients both before and after matching (P = 0.424 and P = 0.281, respectively). In multivariate analysis of the matched population, not receiving postoperative radiotherapy did not correlate with worse survival (hazard ratio: 1.175; P = 0.12). Factors associated with worse survival include sarcomatoid histology, nodal positivity, and age ≥70.

CONCLUSION

Evidence from this analysis is insufficient on its own to routinely recommend postoperative radiotherapy for surgically resected MPM. However, large-scale prospective clinical trials are warranted to further evaluate this intervention in nonsarcomatoid histology.

Intensity-Modulated Radiation Therapy Improves the Target Coverage Over 3-D Planning While Meeting Lung Tolerance Doses for All Patients With Malignant Pleural Mesothelioma

PURPOSE

To investigate high conformality on target coverage and the ability on creating strict lung dose limitation of intensity-modulated radiation therapy in malignant pleural mesothelioma.

PATIENTS AND METHODS

Twenty-four radiation therapy plannings were evaluated and compared with dosimetric outcomes of conformal radiation therapy and intensity-modulated radiation therapy. Hemithoracal radiation therapy was performed on 12 patients with a fraction of 1.8 Gy to a total dose of 50.4 Gy. All organs at risk were contoured. Radiotherapy plannings were differed according to the technique; conformal radiation therapy was planned with conventionally combined photon-electron fields, and intensity-modulated radiation therapy was planned with 7 to 9 radiation beam angles optimized in inverse planning. Strict dose-volume constraints were applied.

RESULTS

Intensity-modulated radiation therapy was statistically superior in target coverage and dose homogeneity (intensity-modulated radiation therapy-planning target volume 95 mean 100%; 3-dimensional conformal radiation therapy-planning target volume 95 mean 71.29%, P = .0001; intensity-modulated radiation therapy-planning target volume 105 mean 11.14%; 3-dimensional conformal radiation therapy-planning target volume 105 mean 35.69%, P = .001). The dosimetric results of the remaining lung was below the limitations on intensity-modulated radiation therapy planning data (intensity-modulated radiation therapy-lung mean dose mean 7.5 [range: 5.6%-8.5%]; intensity-modulated radiation therapy-lung V5 mean 55.55% [range: 47%-59.9%]; intensity-modulated radiation therapy-lung V20 mean 4.5% [range: 0.5%-9.5%]; intensity-modulated radiation therapy-lung V13 mean 13.43% [range: 4.2%-22.9%]).

CONCLUSION

With a complex and large target volume of malignant pleural mesothelioma, intensity-modulated radiation therapy has the ability to deliver efficient tumoricidal radiation dose within the safe dose limits of the remaining lung tissue.

Management of malignant pleural mesothelioma - part 3 : Data from the Austrian Mesothelioma Interest Group (AMIG) database

Background

Malignant pleural mesothelioma (MPM) is a rare but aggressive tumor originating from the pleural cavity with a strong link to previous asbestos exposure. In order to determine the demographics, diagnostics, therapeutic strategies, and prognosis of MPM patients in Austria, the Austrian Mesothelioma Interest Group (AMIG) was founded in 2011. In this report the data from the AMIG MPM database collected to date are reported.

Methods

A prospective observational registry was initiated, including patients with histologically verified MPM diagnosed and treated at specialized centers in Austria. Patient inclusion started in January 2011 and follow-up was completed until September 2015.

Results

A total number of 210 patients were included. There were 167 male and 43 female patients with a mean age of 67.0 years (SD ± 11.3) at the time of diagnosis. Asbestos exposure was confirmed in 109 (69.4 %) patients. The histological subtype was epithelioid in 141 (67.2 %), sarcomatoid in 16 (7.6 %), biphasic in 28 (13.3 %), and MPM not otherwise specified in 25 (11.9 %) patients. Of the patients, 30 (14.3 %) received best supportive care (BSC) only, 71 (33.8 %) chemotherapy (CHT) alone, four (1.9 %) radiotherapy (RT) alone, 23 (11.9 %) CHT/RT, two (0.9 %) surgery alone, and 76 (36.2 %) curative surgery within a multimodality treatment (MMT), which was more frequently performed for patients younger than 65 years and with early-stage disease (I + II). Median overall survival (OS) was 19.1 months (95 % CI 14.7–23.5). The 1‑, 3‑, and 5‑year OS rates were 66 %, 30 %, and 23 %, respectively, and OS was significantly better in patients undergoing surgery within MMT (5-year survival 5 % vs. 40 %, p = 0.001).

Conclusion

Patients with earlier disease stages, younger age, good performance status, and epithelioid histology were more likely to undergo MMT including surgery, which resulted in a more favorable outcome.

Asbestos exposure and mesothelioma incidence and mortality in Bulgaria

Bulgaria totally banned the import, production and use of asbestos in 2005, but produced and used asbestos products during the last 3-4 decades of the 20th century. The aim of this study was to follow the incidence and mortality of mesothelioma in Bulgaria in relation to past occupational exposures. A literature search between 1960 and 2014 was conducted to obtain information on asbestos consumption, occupational exposure and asbestos-related diseases (ARDs). Data on registered mesotheliomas were provided by the National Cancer Register and data for recognized occupational ARDs were provided by the National Social Security Institute. An increase in the incidence of mesothelioma from 5 to 58 from 1993 to 2013, with 666 cases in the 21-year period, was registered. Incidence, mortality rates, deaths and male-to-female ratios and were lower in comparison to industrialized countries. The increase in mesothelioma incidence is considered as a consequence of more recent production and use of asbestos and asbestos products and the high occupational exposure between 1977 and 1989, while the lower rate of mesothelioma deaths and male-to-female ratio need to be investigated further.

The global health dimensions of asbestos and asbestos-related diseases

The Collegium Ramazzini is an international scientific society that examines critical issues in occupational and environmental medicine with a view towards action to prevent disease and promote health. The Collegium derives its name from Bernardino Ramazzini, the father of occupational medicine, a professor of medicine of the Universities of Modena and Padua in the late 1600s and the early 1700s. The Collegium is comprised of 180 physicians and scientists from 35 countries, each of whom is elected to membership. The Collegium is independent of commercial interests.

Classification and management of asbestos-containing waste: European legislation and the Italian experience

OBJECTIVE

Production of a new classification of Asbestos Containing Products (ACPs), materials (ACM) and Asbestos Containing Waste (ACW), in addition to a correct identification of landfills where ACW should be disposed of in Europe.

METHODS

Analysis of the European and Italian legislation, study of waste classification and management in the main European countries, data analysis of mapping of Italian landfills and quantification of ACW disposed there.

FINDINGS

Classification according to unique criteria (physical state, substances with which asbestos minerals have been blended, function of the asbestos, etc.). Highlights of cases of incorrect management of ACW in Europe, specifying the Italian ones. Considering the significant inconsistencies between the European and national regulations and the actual implementation of those regulations, this paper provide some precise indications for the proper assignment to ACW of the European Waste Catalogue (EWC) codes. Lastly, suitable types of landfills at which ACW should be disposed of have been identified, in order to assisting the persons involved in ACW management to avoid undue exposition and their improper disposal.

CONCLUSION

This study reports a useful manual for classifying worldwide ACPs based on their physical state and considering the substances with which the asbestos minerals have been blended. Moreover several clear tables allow the asbestos remediation and waste management operators to suitably classify and dispose of ACW.

Estimating the incidence of malignant mesothelioma in Vietnam: a pilot descriptive cancer registration study

INTRODUCTION

Global asbestos consumption has shifted toward lower income countries, particularly in the Asian region including Vietnam where asbestos and asbestos-containing products have been imported since the late 1960s.

METHODS

This pilot descriptive epidemiological study aimed to provide contemporary estimates of malignant mesothelioma incidence (histological subtype M9050/3; ICD-O-3) by gender and age group as recorded across nine cancer registries in Vietnam.

RESULTS

We identified 148 incident cases of malignant mesothelioma during 1987-2013. The majority of cases were recorded in the Hanoi region (n = 93) and were aged 55 years or older (n = 96).

DISCUSSION

By carefully reviewing existing cancer registry records in Vietnam, we identified a larger number of malignant mesothelioma cases than previously estimated. We recommend the use of cancer registry data in tracking future asbestos-related disease in Vietnam.

UK asbestos imports and mortality due to idiopathic pulmonary fibrosis

BACKGROUND

Previous studies have demonstrated that the rising mortality due to mesothelioma and asbestosis can be predicted from historic asbestos usage. Mortality due to idiopathic pulmonary fibrosis (IPF) is also rising, without any apparent explanation.

AIMS

To compare mortality due to these conditions and examine the relationship between mortality and national asbestos imports.

METHODS

Mortality data for IPF and asbestosis in England and Wales were available from the Office for National Statistics. Data for mesothelioma deaths in England and Wales and historic UK asbestos import data were available from the Health & Safety Executive. The numbers of annual deaths due to each condition were plotted separately by gender, against UK asbestos imports 48 years earlier. Linear regression models were constructed.

RESULTS

For mesothelioma and IPF, there was a significant linear relationship between the number of male and female deaths each year and historic UK asbestos imports. For asbestosis mortality, a similar relationship was found for male but not female deaths. The annual numbers of deaths due to asbestosis in both sexes were lower than for IPF and mesothelioma.

CONCLUSIONS

The strength of the association between IPF mortality and historic asbestos imports was similar to that seen in an established asbestos-related disease, i.e. mesothelioma. This finding could in part be explained by diagnostic difficulties in separating asbestosis from IPF and highlights the need for a more accurate method of assessing lifetime occupational asbestos exposure.

An intrapleural administration of zoledronic acid for inoperable malignant mesothelioma patients: a phase I clinical study protocol

Background

The third generation of bisphosphonates is clinically in use for patients of osteoporosis or malignancy-linked hypercalcemia. The agents can also produce anti-tumor effects on bone metastasis of several types of tumors. We recently found that one of the agents achieved cytotoxicity to mesothelioma in vitro and in an orthotopic animal model. Mesothelioma is resistant to a number of chemotherapeutic agents, and suppression of local tumor growth is beneficial to the patients since metastasis to extra-thoracic organs is relatively infrequent until a late stage.

Methods/design

We demonstrated in an orthotopic mouse model that an intrapleural but not intravenous injection of zoledronic acid, one of the third generation bisphosphonates, at a clinically equivalent dose suppressed the tumor growth. Nevertheless, a high concentration of zoledronic acid administrated in the pleural cavity produced pleural adhesion. We also showed that zoledronic acid produced synergistic cytotoxic effects with cisplatin, the first-line chemotherapeutic agent for mesothelioma. We then planned to conduct a phase I clinical study to investigate any adverse effects and a possible clinical benefits produced by an intrapleural administration of zoledronic acid to mesothelioma patients who became resistant to the first-line chemotherapeutic agents. The clinical trial is a dose escalation study starting with 0.4, 1, 4, 8 and 16 mg per person since safety of administration of zoledronic acid into the pleural cavity remains unknown. Each dose group consists of three persons and the protocol allows to repeat administration of the same dose into the pleural cavity at a 4-weeks interval.

Discussion

We will conduct a possible combinatory study of intrapleural administration of zoledronic acid and systemic administration of the first-line agent to a chemotherapy-naïve patient based on the maximum tolerance dose of zoledronic acid determined by the present clinical trial. We propose that administration of bisphosphonates in a closed cavity is a treatment strategy for tumors developed in the cavity probably through the direct cytotoxic activity.

Trial registration: UMIN clinical trials registry, Japan. Register ID: UMIN8093.

Mesothelioma from asbestos exposures: Epidemiologic patterns and impact in the United States

Mesothelioma, a rare tumor, is highly correlated with asbestos exposure. Mesothelioma, similar to all asbestos-related diseases, is dose/intensity dependent to some degree, and studies showed the risk of mesothelioma rises with cumulative exposures. Multiple processes occur in an individual before mesothelioma occurs. The impact of mesothelioma in the United States has been continuous over the last half century, claiming between 2,000 and 3,000 lives each year. Mesothelioma is a preventable tumor that is more frequently reported as associated with asbestos exposure among men than women. However, the rate of asbestos-associated mesothelioma is on the rise among women due to better investigation into their histories of asbestos exposure. It is of interest that investigators detected asbestos-associated cases of mesothelioma in women from nonoccupational sources-that is, bystander, incidental, or take-home exposures. It is postulated that asbestos-associated mesotheliomas, in both men and women, are likely underreported. However, with the implementation of the most recent ICD-10 coding system, the correlation of mesothelioma with asbestos exposure is expected to rise to approximately 80% in the United States. This study examined the demographic and etiological nature of asbestos-related mesothelioma.

The global health dimensions of asbestos and asbestos-related diseases

The Collegium Ramazzini is an international scientific society that examines critical issues in occupational and environmental medicine with a view towards action to prevent disease and promote health. The Collegium derives its name from Bernardino Ramazzini, the father of occupational medicine, a professor of medicine of the Universities of Modena and Padua in the late 1600s and the early 1700s. The Collegium is comprised of 180 physicians and scientists from 35 countries, each of whom is elected to membership. The Collegium is independent of commercial interests.

Advances in the diagnosis, treatment and prognosis of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a rare cancer originated from pleural mesothelial cells. MPM has been associated with long-term exposure to asbestos. The prognosis of MPM is poor due to the difficulty of making diagnosis in the early stage, the rapid progression, the high invasiveness and the lack of effective treatment. Although the incidence of MPM is low in China to date, it has a tendency to increase in the coming years. The variety of clinical features may cause the delay of diagnosis and high rate of misdiagnosis. The diagnosis of MPM is based on biopsy of the pleura and immunohistochemistry. As China has become the largest country in the consumption of asbestos, it would give rise to a new surge of MPM in the future. The current treatment of MPM is multimodality therapy including surgery, radiotherapy, chemotherapy and immunotherapy. Two surgical procedures are commonly applied: extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D). Three dimensional conformal radiotherapy is used to denote a spectrum of radiation planning and delivery techniques that rely on the 3D imaging to define the tumor. Cisplatin combined with pemetrexed (PEM) is the first-line chemotherapy for MPM. The principal targets in immunotherapy include T cells (Treg), CTLA-4 and PD-1. The diagnosis, treatment and prognosis still remain a major challenge for clinical research and will do so for years to come.

The next mesothelioma wave: mortality trends and forecast to 2030 in Brazil

BACKGROUND

There are limited data on mesothelioma mortality in industrializing countries, where, at present, most of the asbestos consumption occurs.

OBJECTIVES

To analyze temporal trends and to calculate mortality rates from mesothelioma and cancer of the pleura in Brazil from 2000 to 2012 and to estimate future mortality rates.

METHODS

We retrieved records of deaths from mesothelioma (ICD-10C45) and cancer of the pleura (ICD-10C38.4) from 2000 to 2012 in adults aged 30 years and over. Crude and age-standardized mortality rates (ASMR) were calculated. Rate ratios of mean crude mortality for selected municipalities were compared to the Brazilian rate. A regression was carried out of the annual number of deaths against asbestos consumption using a Generalized Additive Model (GAM). The best model was chosen to estimate the future burden and peak period of deaths.

RESULTS

There were 929C45 and 1379 C38.4 deaths. The ratio of men to women for C45 was 1.4. A positive trend in C45 numbers was observed in Brazil (p=0.0012), particularly in São Paulo (p=0.0004) where ASMRs presented an increasing linear trend (p=0.0344). Selected municipalities harboring asbestos manipulation presented 3.7-11 fold rate ratios of C45 compared to Brazil. GAM presented best fits for latencies of 34 years or more. It is estimated that the peak incidence of C45 mortality will occur between 2021 and 2026.

CONCLUSIONS

The observed ASMRs and the gender ratio close to 1 suggest underreporting. Even so, deaths are increasing and mesothelioma clusters were identified. Compared to industrialized countries Brazil displays a 15-20 year lag in estimated peak mesothelioma mortality which is consistent with the lag of asbestos peak consumption in the country.

Emerging evidence that the ban on asbestos use is reducing the occurrence of pleural mesothelioma in Sweden

AIMS

Several countries have banned the use of asbestos. The future health impacts of previous use have been modeled but there are to our knowledge no convincing studies showing a decreased occurrence of asbestos-related diseases due to a ban. The aim of our study was to estimate the effects of the ban and other measures to decrease the use of asbestos in Sweden.

METHODS

The effect was measured through comparing the incidence of pleural malignant mesothelioma in birth cohorts who started to work before and after the decrease in the use of asbestos, i.e. in mid-1970s. Cases were identified through the Swedish Cancer Registry and the analysis was restricted to persons born in Sweden.

RESULTS

Men and women born 1955-79 had a decreased risk of malignant pleural mesothelioma compared to men and women born 1940-49 (RR 0.16, 95% CI 0.11-0.25; and RR 0.47, 95% CI 0.23-0.97 respectively). The decreased use of asbestos prevented each year about 10 cases in men and two cases in women below the age of 57 years in 2012.

CONCLUSIONS

The ban and decreased use of asbestos in Sweden can be measured today in birth cohorts that started their working career after the decrease.

A clinical protocol to inhibit the HGF/c-Met pathway for malignant mesothelioma with an intrapleural injection of adenoviruses expressing the NK4 gene

Background

The hepatocyte growth factor (HGF)/c-Met signal pathway is up-regulated in human mesothelioma and suppression of the HGF/c-Met signaling with a competitive inhibitor, NK4 homologous to HGF in the structure, produced anti-tumor effects to mesothelioma in a preclinical study. Mesothelioma is highly resistant to a number of chemotherapeutic agents but distant metastasis to extra-thoracic organs is relatively infrequent until the late stage.

Methods/design

We planned to conduct a clinical study of gene therapy with adenoviruses expressing the NK4 gene (Ad-NK4) to control the local tumor growth. The study is designed to inject Ad-NK4 into the intrapleural cavity with a dose escalation manner from 10¹⁰ to 10¹² virus particles per patient and to examine safety and possible clinical benefits. The clinical investigation is a first-in-human trial to use the NK4 gene and to block the HGF/c-Met pathway with gene medicine. We conducted in vivo animal experiments to examine the safety level as one of the preclinical studies, and showed that Ad DNA administered in the pleural cavity was detected in many parenchymal organs. Biochemical and pathological analyses showed that liver damages were the major adverse effects with little toxicity to other organs. These studies firstly demonstrated biodistribution and transgene expression after an intrapleural injection of Ad vectors in an animal study, which contrasts with an intravenous injection showing relatively rapid clearance of Ad-NK4.

Discussion

The clinical study can also provide information regarding production of NK4 protein and antibody against NK4, and inhibition levels of the HGF/c-Met pathway by detecting dephosphorylation of c-Met in mesothelioma cells. These data will be crucial to judge whether local production of NK4 molecules can be an anti-cancer strategy.

Trial registration: UMIN clinical trials registry, Japan. Register ID: UMIN15771

Epigenetic down-regulation of integrin α7 increases migratory potential and confers poor prognosis in malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a devastating malignancy characterized by invasive growth and rapid recurrence. The identification and inhibition of molecular components leading to this migratory and invasive phenotype are thus essential. Accordingly, a genome-wide expression array analysis was performed on MPM cell lines and a set of 139 genes was identified as differentially expressed in cells with high versus low migratory activity. Reduced expression of the novel tumour suppressor integrin α7 (ITGA7) was found in highly motile cells. A significant negative correlation was observed between ITGA7 transcript levels and average displacement of cells. Forced overexpression of ITGA7 in MPM cells with low endogenous ITGA7 expression inhibited cell motility, providing direct evidence for the regulatory role of ITGA7 in MPM cell migration. MPM cells showed decreased ITGA7 expressions at both transcription and protein levels when compared to non-malignant mesothelial cells. The majority of MPM cell cultures displayed hypermethylation of the ITGA7 promoter when compared to mesothelial cultures. A statistically significant negative correlation between ITGA7 methylation and ITGA7 expression was also observed in MPM cells. While normal human pleura samples unambiguously expressed ITGA7, a varying level of expression was found in a panel of 200 human MPM samples. In multivariate analysis, ITGA7 expression was found to be an independent prognostic factor. Although there was no correlation between histological subtypes and ITGA7 expression, importantly, patients with high tumour cell ITGA7 expression had an increased median overall survival compared to the low- or no-expression groups (463 versus 278 days). In conclusion, our data suggest that ITGA7 is an epigenetically regulated tumour suppressor gene and a prognostic factor in human MPM.

Tetralogy of Fallot and Hypoplastic Left Heart Syndrome - Complex Clinical Phenotypes Meet Complex Genetic Networks

In many cases congenital heart disease (CHD) is represented by a complex phenotype and an array of several functional and morphological cardiac disorders. These malformations will be briefly summarized in the first part focusing on two severe CHD phenotypes, hypoplastic left heart syndrome (HLHS) and tetralogy of Fallot (TOF). In most cases of CHD the genetic origin remains largely unknown, though the complexity of the clinical picture strongly argues against a dysregulation which can be attributed to a single candidate gene but rather suggests a multifaceted polygenetic origin with elaborate interactions. Consistent with this idea, genome-wide approaches using whole exome sequencing, comparative sequence analysis of multiplex families to identify de novo mutations and global technologies to identify single nucleotide polymorphisms, copy number variants, dysregulation of the transcriptome and epigenetic variations have been conducted to obtain information about genetic alterations and potential predispositions possibly linked to the occurrence of a CHD phenotype. In the second part of this review we will summarize and discuss the available literature on identified genetic alterations linked to TOF and HLHS.

Fast neutron radiotherapy in the treatment of malignant pleural mesothelioma

INTRODUCTION

Malignant pleural mesothelioma (MPM) is a fatal disease lacking standardized treatment. We describe the use of fast neutron radiation therapy in MPM patients referred to the Department of Radiation Oncology at the University of Washington Medical Center.

MATERIALS AND METHODS

Retrospective chart review of MPM patients receiving neutron radiotherapy treatment from 1980 to 2012.

RESULTS

A total of 30 MPM patients received fast neutron radiotherapy as part of their treatment regimen. Median age at diagnosis was 59.6 years (range, 46.6 to 72.3 y). Eighteen patients received fast neutron radiotherapy as a component of trimodality treatment. Median overall survival was 20.3 months (range, 5.5 to 73.3 mo) with 1 patient censored at 34.8 months and all other patients with confirmed dates of death. One patient receiving radiotherapy alone as a palliative measure died during radiation treatment. One patient was unable to tolerate radiotherapy and stopped before completing prescribed treatment. On univariate analysis, Brigham Stage at presentation was a significant predictor of survival (P<0.01). No significant differences in survival were observed when comparing patients who received trimodality treatment compared to those who did not.

CONCLUSIONS

Fast neutron radiotherapy may be utilized in the management of MPM patients. However, treatment with fast neutron radiotherapy did not significantly improvement outcome, even when used in a trimodality regimen.

Asbestos: use, bans and disease burden in Europe

OBJECTIVE

To analyse national data on asbestos use and related diseases in the European Region of the World Health Organization (WHO).

METHODS

For each of the 53 countries, per capita asbestos use (kg/capita/year) and age-adjusted mortality rates (deaths/million persons/year) due to mesothelioma and asbestosis were calculated using the databases of the United States Geological Survey and WHO, respectively. Countries were further categorized by ban status: early-ban (ban adopted by 2000, n = 17), late-ban (ban adopted 2001-2013, n = 17), and no-ban (n = 19).

FINDINGS

Between 1920-2012, the highest per capita asbestos use was found in the no-ban group. After 2000, early-ban and late-ban groups reduced their asbestos use levels to less than or equal to 0.1 kg/capita/year, respectively, while the no-ban group maintained a very high use at 2.2 kg/capita/year. Between 1994 and 2010, the European Region registered 106,180 deaths from mesothelioma and asbestosis, accounting for 60% of such deaths worldwide. In the early-ban and late-ban groups, 16/17 and 15/17 countries, respectively, reported mesothelioma data to WHO, while only 6/19 countries in the no-ban group reported such data. The age-adjusted mortality rates for mesothelioma for the early-ban, late-ban and no-ban groups were 9.4, 3.7 and 3.2 deaths/million persons/year, respectively. Asbestosis rates for the groups were 0.8, 0.9 and 1.5 deaths/million persons/year, respectively.

CONCLUSION

Within the European Region, the early-ban countries reported most of the current asbestos-related deaths. However, this might shift to the no-ban countries, since the disease burden will likely increase in these countries due the heavy use of asbestos.

Diagnosis and treatment of malignant pleural mesothelioma

There are three major challenges in the diagnosis of malignant pleural mesothelioma: mesothelioma must be distinguished from benign mesothelial hyperplasia; malignant mesothelioma (and its subtypes) must be distinguished from metastatic carcinoma; and invasion of structures adjacent to the pleura must be demonstrated. The basis for clarifying the first two aspects is determination of a panel of monoclonal antibodies with appropriate immunohistochemical evaluation performed by highly qualified experts. Clarification of the third aspect requires sufficiently abundant, deep biopsy material, for which thoracoscopy is the technique of choice. Video-assisted needle biopsy with real-time imaging can be of great assistance when there is diffuse nodal thickening and scant or absent effusion. Given the difficulties of reaching an early diagnosis, cure is not generally achieved with radical surgery (pleuropneumonectomy), so liberation of the tumor mass with pleurectomy/decortication combined with chemo- or radiation therapy (multimodal treatment) has been gaining followers in recent years. In cases in which surgery is not feasible, chemotherapy (a combination of pemetrexed and platinum-derived compounds, in most cases) with pleurodesis or a tunneled pleural drainage catheter, if control of pleural effusion is required, can be considered. Radiation therapy is reserved for treatment of pain associated with infiltration of the chest wall or any other neighboring structure. In any case, comprehensive support treatment for pain control in specialist units is essential: this acquires particular significance in this type of malignancy.

Significance of serum mesothelin in an asbestos-exposed population in the Czech Republic

AIMS

Pleural mesothelioma is a highly aggressive and difficult-to-treat form of cancer induced by asbestos in 80-90% of cases. The population group most at risk of the condition are asbestos-exposed workers. Mesothelin or soluble mesothelin-related protein (SMRP) is studied as a potential marker of mesothelioma in the at-risk population.

METHODS

The study comprised 239 subjects with a mean duration of occupational exposure to asbestos of 19.9 years. In all of them, a complete medical history was taken, focused on exposure duration and a physical examination, a chest X-ray or other imaging investigations and a lung function test were performed. Their serum SMRP levels were measured and biopsy samples were taken to diagnose pleural disease. Based on the above examinations, the subjects were classified into subgroups and serum SMRP concentrations were statistically analyzed with respect to individual parameters.

RESULTS

In asbestos-exposed individuals, mesothelin levels were significantly higher in those with pathological X-ray findings than in those with normal X-ray results (0.78 ± 0.63 vs. 0.50 ± 0.35, P<0.0001). The group of patients with benign disease had statistically significantly higher mesothelin levels than those with normal X-ray findings (0.755 ± 0.543 vs. 0.50 ± 0.35, P<0.001). In the group with present malignant processes, mesothelin levels were higher than in individuals with benign disease (1.19 ± 0.89 vs. 0.76 ± 0.54, P=0.015). Only a weak correlation was found between mesothelin levels and asbestos exposure duration. There were relatively high sensitivity and high specificity (75% and 90.6%, respectively) of serum mesothelin for pleural mesothelioma. However, given the small number of mesothelioma cases in the group, the results cannot be considered as statistically significant.

CONCLUSIONS

In persons followed up for asbestos exposure, increased mesothelin levels signalize pathological processes in the chest and correlate with severity of the disease. The study suggests that mesothelin cannot be considered a reliable marker for the early stage of malignant degeneration of pleural disease but only an additional criterion for examination of the followed-up individuals.

Radiological surveillance of formerly asbestos-exposed power industry workers: rates and risk factors of benign changes on chest X-ray and MDCT

BACKGROUND

To determine the prevalence of asbestos-related changes on chest X-ray (CXR) and low-dose multidetector-row CT (MDCT) of the thorax in a cohort of formerly asbestos-exposed power industry workers and to assess the importance of common risk factors associated with specific radiological changes.

METHODS

To assess the influence of selected risk factors (age, time since first exposure, exposure duration, cumulative exposure and pack years) on typical asbestos-related radiographic changes, we employed multiple logistic regression and receiver operating characteristic (ROC) analysis.

RESULTS

On CXR, pleural changes and asbestosis were strongly associated with age, years since first exposure and exposure duration. The MDCT results showed an association between asbestosis and age and between plaques and exposure duration, years since first exposure and cumulative exposure. Parenchymal changes on CXR and MDCT, and diffuse pleural thickening on CXR were both associated with smoking. Using a cut-off of 55 years for age, 17 years for exposure duration and 28 years for latency, benign radiological changes in the cohort with CXR could be predicted with a sensitivity of 82.0% for all of the three variables and a specificity of 47.4%, 39.0% and 40.6%, respectively.

CONCLUSIONS

Participants aged 55 years and older and those with an asbestos exposure of at least 17 years or 28 years since first exposure should be seen as having an increased risk of abnormal radiological findings. For implementing a more focused approach the routine use of low-dose MDCT rather than CXR at least for initial examinations would be justified.

Potential effects of environmental chemical contamination in congenital heart disease

There is compelling evidence that prenatal exposures to environmental xenobiotics adversely affect human development and childhood. Among all birth defects, congenital heart disease (CHD) is the most prevalent of all congenital malformations and remains the leading cause of death. It has been estimated that in most cases the causes of heart defects remain unknown, while a growing number of studies have indicated the potential role of environmental agents as risk factors in CHD occurrence. In particular, maternal exposure to chemicals during the first trimester of pregnancy represents the most critical window of exposure for CHD. Specific classes of xenobiotics (e.g. organochlorine pesticides, organic solvents, air pollutants) have been identified as potential risk factors for CHD. Nonetheless, the knowledge gained is currently still incomplete as a consequence of the frequent heterogeneity of the methods applied and the difficulty in estimating the net effect of environmental pollution on the pregnant mother. The presence of multiple sources of pollution, both indoor and outdoor, together with individual lifestyle factors, may represent a further confounding element for association with the disease. A future new approach for research should probably focus on individual measurements of professional, domestic, and urban exposure to physical and chemical pollutants in order to accurately retrace the environmental exposure of parents of affected offspring during the pre-conceptional and pregnancy periods.

Asbestos Exposure Causes Mesothelioma, But Not This Asbestos Exposure: An Amicus Brief to the Michigan Supreme Court

Manufacturers of asbestos brakes, supported by many manufacturing and insurance industry amicus curie, requested the Michigan Supreme Court to dismiss testimony of an expert regarding the ability of asbestos dust from brakes to cause mesothelioma as "junk science". Scientists are concerned with the sweeping and unequivocal claims that any conclusion that asbestos from brakes caused a signature asbestos-related disease in a particular person must be "junk science". The manufacturers' sweeping pronouncements are what veer from accepted, reliable mainstream scientific methods and conclusions. This article outlines the evidence supporting the conclusion that asbestos from brakes can and does cause mesothelioma, and describes the defendants' attempts to fabricate doubt about this conclusion.