Recent mortality from pleural mesothelioma, historical patterns of asbestos use, and adoption of bans: a global assessment

From Diagnosis to Survivorship: The Role of Social Determinants in Cancer Care

Social determinants of health (SDOH) profoundly influence cancer outcomes. Disparities in these areas contribute to delayed diagnoses, limited access to advanced treatments, and poorer survival rates, disproportionately affecting marginalized populations. While advancements in cancer care have improved survival, these benefits remain unevenly distributed. This review examines the impact of SDOH on cancer care across multiple domains. It highlights the ways in which structural barriers exacerbate disparities in prevention, diagnosis, and treatment. Evidence-based interventions, including Medicaid expansion, culturally tailored patient navigation programs, increased diversity in clinical trials, telemedicine expansion, and the integration of SDOH screening into oncology workflows-offer promising strategies for addressing these inequities. By integrating these strategies into clinical practice and health policy, the healthcare system can foster a more just and inclusive future for cancer treatment and survivorship.

Lung cancer statistics, 2023

Despite decades of declining mortality rates, lung cancer remains the leading cause of cancer death in the United States. This article examines lung cancer incidence, stage at diagnosis, survival, and mortality using population-based data from the National Cancer Institute, the Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries. Over the past 5 years, declines in lung cancer mortality became considerably greater than declines in incidence among men (5.0% vs. 2.6% annually) and women (4.3% vs. 1.1% annually), reflecting absolute gains in 2-year relative survival of 1.4% annually. Improved outcomes likely reflect advances in treatment, increased access to care through the Patient Protection and Affordable Care Act, and earlier stage diagnosis; for example, compared with a 4.6% annual decrease for distant-stage disease incidence during 2013-2019, the rate for localized-stage disease rose by 3.6% annually. Localized disease incidence increased more steeply in states with the highest lung cancer screening prevalence (by 3%-5% annually) than in those with the lowest (by 1%-2% annually). Despite progress, disparities remain. For example, Native Americans have the highest incidence and the slowest decline (less than 1% annually among men and stagnant rates among women) of any group. In addition, mortality rates in Mississippi and Kentucky are two to three times higher than in most western states, largely because of elevated historic smoking prevalence that remains. Racial and geographic inequalities highlight longstanding opportunities for more concerted tobacco-control efforts targeted at high-risk populations, including improved access to smoking-cessation treatments and lung cancer screening, as well as state-of-the-art treatment.

Do patterns of past asbestos use and production reflect current geographic variations of cancer risk?: mesothelioma in Ontario and British Columbia, Canada

PURPOSE

Canada was a major global asbestos producer and consumer. Geographic patterns of Canadian asbestos use and mesothelioma, a highly fatal cancer linked to asbestos exposure, have not been previously reported. This study summarized key trends in mesothelioma incidence by geography and time in two Canadian provinces, Ontario and British Columbia (BC), and explored how past workforce characteristics and geographic trends in asbestos production and use may shape variations in regional rates of mesothelioma.

METHODS

We report trends in mesothelioma incidence (1993-2016) for Ontario and British Columbia using population-based incidence data that were age-standardized to the 2011 Canadian population. Historical records of asbestos production and use were analyzed to geo-locate industrial point sources of asbestos in Ontario and BC. The prevalence of occupations in regions with the highest and lowest rates of mesothelioma in Ontario and BC were calculated using labor force statistics from the 1981 Canadian Census.

RESULTS

Regional mesothelioma rates varied in both provinces over time; more census divisions in both Ontario and BC registered mesothelioma rates in the highest quintile of incidences during the period 2009 to 2016 than in any prior period examined. Certain occupations such as construction trades workers were more likely to be overrepresented in regions with high mesothelioma rates.

CONCLUSION

This work explored how studying asbestos exposure and mesothelioma incidence at small-scale geographies could direct cancer surveillance and research to more targeted areas. Findings indicated that regional variations in mesothelioma could signal important differences in past occupational and potentially environmental exposures.

The Potential Contribution of Hexavalent Chromium to the Carcinogenicity of Chrysotile Asbestos

Chrysotile asbestos is a carcinogenic mineral that has abundantly been used in industrial and consumer applications. The carcinogenicity of the fibers is partly governed by reactive Fe surface sites that catalyze the generation of highly toxic hydroxyl radicals (HO•) from extracellular hydrogen peroxide (H2O2). Chrysotile also contains Cr, typically in the low mass permille range. In this study, we examined the leaching of Cr from fibers at the physiological lung pH of 7.4 in the presence and absence of H2O2. Furthermore, we investigated the potential of cells from typical asbestos-burdened tissues and cancers to take up Cr leached from chrysotile in PCR expression, immunoblot, and cellular Cr uptake experiments. Finally, the contribution of Cr to fiber-mediated H2O2 decomposition and HO• generation was studied. Chromium readily dissolved from chrysotile fibers in its genotoxic and carcinogenic hexavalent redox state upon oxidation by H2O2. Lung epithelial, mesothelial, lung carcinoma, and mesothelioma cells expressed membrane-bound Cr(VI) transporters and accumulated Cr up to 10-fold relative to the Cr(VI) concentration in the spiked medium. Conversely, anion transporter inhibitors decreased cellular Cr(VI) uptake up to 45-fold. Finally, chromium associated with chrysotile neither decomposed H2O2 nor contributed to fiber-mediated HO• generation. Altogether, our results support the hypothesis that Cr may leach from inhaled chrysotile in its hexavalent state and subsequently accumulate in cells of typically asbestos-burdened tissues, which could contribute to the carcinogenicity of chrysotile fibers. However, unlike Fe, Cr did not significantly contribute to the adverse radical production of chrysotile.

Investigation of asbestos concentration in ambient and lavage fluids of patients referred for bronchoscopy, Ahvaz

Introduction

The amount of fibers in the lungs is considered to reflect the cumulative intensity of past asbestos exposure, and bronchoalveolar lavage (BAL) has been proposed to be a good indicator of the presence and quantity of asbestos particles in the lungs. This study evaluated the asbestos concentration in BAL fluids of asbestos-exposed and unexposed pulmonary patients and the environment of Ahvaz city.

Methods

This prospective study was conducted on 80 patients underwent diagnostic fiberoptic bronchoscopy referred to Imam Khomeini Hospital in Ahvaz, Iran, in 2019. Patients with Lung diseases were divided into three groups based on CT scan results: normal (n = 32), lung cancer (n = 40) and Interstitial lung disease (n = 8). The analysis of asbestos fiber concentration in BAL fluid was carried out by Scanning Electron Microscope (SEM).

Results

The positive asbestos test was detected in 69% of all subjects, including 64% of whom had asbestos-related jobs and 74.5% of those with non-related jobs (p = 0.240). The concentrations of asbestos fiber in the BAL in normal patients, lung cancer and interstitial fibrosis (ILD) were 8.13 ± 5.38, 9.66 ± 7.30 and 6.31 ± 1.98 f/ml, respectively (P = 0.492). There was no significant difference between the asbestos levels and exposure history (P = 0.877). The mean concentration of asbestos in the ambient air during the current year was 2.69 ± 0.57 f/ml (2.26-3.70), and the correlation between asbestos levels in BAL and the air was not significant (r = 0.147; P = 0.243).

Conclusions

The exposure of different occupational and non-occupational groups to this carcinogenic substance indicates the need for environmental and individual control measures to reduce and prevent asbestos exposure.

Soil-pH and cement influence the weathering kinetics of chrysotile asbestos in soils and its hydroxyl radical yield

Chrysotile asbestos is a toxic and carcinogenic mineral that has been used in a variety of industrial and consumer applications. Much of the fiber- and cement-containing asbestos waste has ended up in terrestrial environments. Chrysotile weathering in soils and the potential for natural attenuation have, however, hardly been examined yet. Here we explored how soil properties influence the dissolution rate of chrysotile, the release of the carcinogenic metals chromium and nickel, and the hydroxyl radical (HO^•) generation by chrysotile fibers. Chrysotile dissolution rates in soil suspensions decreased with increasing soil-pH and were lower than reported rates in soil-free systems. Dissolved organic carbon did not markedly accelerate dissolution at circumneutral pH, whereas cement mixed with soil inhibited dissolution because of its alkalinity. The HO^•-yield of incubated fibers in non-amended soils eventually decreased by 60-75%. The decline was fastest in an acidic podzol soil, yet was followed by a small rebound. Cement amendment induced the largest HO^•-yield reduction (∼90%), presumably due to surface coating of the fibers. Overall, this work demonstrates that the potential for natural attenuation of chrysotile asbestos in soils critically depends on soil chemical parameters and the presence of cement in association with the fibers.

Asbestos and Zeolites: from A to Z via a Common Ion

Asbestos and zeolites are silicate-based minerals, linked inextricably via paradoxical similarities and differences which have emanated from different geological epochs. Both have been employed in the service of humanity through millennia: asbestos, for its "inextinguishable" quality of being an insulator against heat and fire; zeolite, a "boiling stone" with its volcanic and marine sedimentary rock origins, for its propensity to adsorb water and remove metals and toxins. Serious adverse health effects observed in asbestos miners as long ago as the 1st Century AD did not halt the rising popularity of asbestos. As the miracle material of the 1900s, asbestos production and consumption exploded, culminating in its ubiquity in ships, vehicles, homes, commercial buildings, and over 3000 different industrial and household products. Through the 1940s and 1950s, epidemiological studies concluded that asbestos was a likely cause of asbestosis, lung cancer, and malignant mesothelioma, and it is now banned in many but far from all countries. The long latency between exposure to asbestos and the occurrence of cancer has obscured the deadly consequences of asbestos exposure for centuries. Even today, a considerable part of the world population is insufficiently aware of the dangers of asbestos, and millions of tons of this carcinogen continue to be mined and used worldwide. Zeolites, both natural and synthetic, are microporous aluminosilicate minerals commonly used in a myriad of processes, in the petrochemical industry, in domestic appliances and cleaning agents, as commercial adsorbents and exchangers for toxins and pollutants, and as catalysts. Zeolites are found in agriculture, veterinary science, and human health. More recently, new materials such as carbon nanotubes are being employed in materials requiring durability and thermal and electrical conductivity, yet nanotubes are now joining the ranks of more established particulates such as asbestos and silica, in causing human disease. In this review, we compare and contrast the similarities and differences of these two groups of silicate minerals and their waxing and waning use in the employ of humanity.

Burden of Mesothelioma Deaths by National Income Category: Current Status and Future Implications

Background: This study compares estimates of the global-level mesothelioma burden with a focus on how existing national mortality data were utilized and further assesses the interrelationship of country-level mesothelioma burden and asbestos use with national income status. Methods: Country-level mesothelioma deaths in the WHO Mortality Database as of December 2019 were analyzed by national income category of countries in terms of data availability and reliability. Numbers of mesothelioma deaths from the study of Odgerel et al. were reanalyzed to assess country-level mesothelioma death burdens by national income status. Results: Among 80 high-income countries, 54 (68%) reported mesothelioma to the WHO and 26 (32%) did not, and among 60 upper middle-income countries, the respective numbers (proportions) were 39 (65%) countries and 21 (35%) countries, respectively. In contrast, among 78 low- and lower middle-income countries, only 11 (14%) reported mesothelioma deaths while 67 (86%) did not. Of the mesothelioma deaths, 29,854 (78%) were attributed to high- and upper middle-income countries, and 8534 (22%) were attributed to low- and lower middle- income countries. Conclusions: The global mesothelioma burden, based on reported numbers, is currently shouldered predominantly by high-income countries; however, mesothelioma burdens will likely manifest soon in upper middle-income and eventually in low and lower middle-income countries.

Identifying the reactive sites of hydrogen peroxide decomposition and hydroxyl radical formation on chrysotile asbestos surfaces

Background

Fibrous chrysotile has been the most commonly applied asbestos mineral in a range of technical applications. However, it is toxic and carcinogenic upon inhalation. The chemical reactivity of chrysotile fiber surfaces contributes to its adverse health effects by catalyzing the formation of highly reactive hydroxyl radicals (HO^•) from H₂O₂. In this Haber-Weiss cycle, Fe on the fiber surface acts as a catalyst: Fe³⁺ decomposes H₂O₂ to reductants that reduce surface Fe³⁺ to Fe²⁺, which is back-oxidized by H₂O₂ (Fenton-oxidation) to yield HO^•. Chrysotile contains three structural Fe species: ferrous and ferric octahedral Fe and ferric tetrahedral Fe (Fe³⁺_tet). Also, external Fe may adsorb or precipitate onto fiber surfaces. The goal of this study was to identify the Fe species on chrysotile surfaces that catalyze H₂O₂ decomposition and HO^• generation.

Results

We demonstrate that at the physiological pH 7.4 Fe³⁺_tet on chrysotile surfaces substantially contributes to H₂O₂ decomposition and is the key structural Fe species catalyzing HO^• generation. After depleting Fe from fiber surfaces, a remnant fiber-related H₂O₂ decomposition mode was identified, which may involve magnetite impurities, remnant Fe or substituted redox-active transition metals other than Fe. Fe (hydr)oxide precipitates on chrysotile surfaces also contributed to H₂O₂ decomposition, but were per mole Fe substantially less efficient than surface Fe³⁺_tet. Fe added to chrysotile fibers increased HO^• generation only when it became incorporated and tetrahedrally coordinated into vacancy sites in the Si layer.

Conclusions

Our results suggest that at the physiological pH 7.4, oxidative stress caused by chrysotile fibers largely results from radicals produced in the Haber-Weiss cycle that is catalyzed by Fe³⁺_tet. The catalytic role of Fe³⁺_tet in radical generation may also apply to other pathogenic silicates in which Fe³⁺_tet is substituted, e.g. quartz, amphiboles and zeolites. However, even if these pathogenic minerals do not contain Fe, our results suggest that the mere presence of vacancy sites may pose a risk, as incorporation of external Fe into a tetrahedral coordination environment can lead to HO^• generation.

Predictions of Mortality from Pleural Mesothelioma in Italy After the Ban of Asbestos Use

Even if the epidemic of malignant pleural mesothelioma (MPM) is still far from being over worldwide, the health effects of regulations banning asbestos can be evaluated in the countries that implemented them early. Estimates of MPM future burden can be useful to inform and support the implementation of anti-asbestos health policies all around the world. With this aim we described the trends of MPM deaths in Italy (1970-2014) and predicted the future number of cases in both sexes (2015-2039), with consideration of the national asbestos ban that was issued in 1992. The Italian National Statistical Institute (ISTAT) provided MPM mortality figures. Cases ranging from 25 to 89 years of age were included in the analysis. For each five-year period from 1970 to 2014, mortality rates were calculated and age-period-cohort Poisson models were used to predict future burden of MPM cases until 2039. During the period 1970-2014 a total number of 28,907 MPM deaths were observed. MPM deaths increased constantly over the study period, ranging from 1356 cases in 1970-1974 to 5844 cases in 2010-2014. The peak of MPM cases is expected to be reached in the period 2020-2024 (about 7000 cases). The decrease will be slow: about 26,000 MPM cases are expected to occur in Italy during the next 20 years (2020-2039). The MPM epidemic in Italy is far from being concluded despite the national ban implemented in 1992, and the peak is expected in 2020-2024, in both sexes. Our results are consistent with international literature.

Environmental and Occupational Exposure to Asbestos as a Result of Consumption and Use in Poland

Asbestos is harmful to human health; exposure to asbestos causes a wide range of asbestos-related diseases.

AIM

Malignant mesothelioma (MM) is unique to occupational and environmental asbestos exposure.

METHODS

Environmental asbestos exposure was examined in relation to asbestos use and manufacturing, the quantity of the asbestos-containing products still in use, the concentrations of asbestos fibres in the air and the number of MM cases diagnosed each year per county.

RESULTS

The correlation coefficient of the measurements of the asbestos fibre concentrations in the air and the quantity of asbestos-cement products in use is high and amounts to 0.68. Meanwhile, the correlation coefficient of the measurements of asbestos fibre concentrations in air and MM morbidity rate resulting from environmental exposure calculated for particular counties in provinces is low and amounts to 0.37. The highest MM morbidity rate was observed for Małopolskie and Śląskie, a typical industrial area of Poland.

CONCLUSIONS

There are MM cases which are still attributable to occupational asbestos exposure, although MM cases resulting from environmental exposure to asbestos have an increased MM risk. Poland is among those countries with a low MM incidence rate, which seems to be an underestimation of environmental asbestos exposure. As long as asbestos-cement products are used in the environment, actions should be undertaken to protect public health.

Epidemiology of Mesothelioma

Since 1973 the International Agency for Research on Cancer has classified asbestos as a certain carcinogen, but today it is still used in several countries. To date, mesothelioma risk is certainly linked not only to occupational exposures but also to environmental exposures. The incidence and mortality are increasing worldwide, especially in developing countries where asbestos is still often used without adequate measures for worker safety. The epidemiological surveillance systems of related asbestos diseases are instruments of public health adopted internationally. The experience and the operating methodology of the Italian mesothelioma registry and the data produced from 1996 to 2015 highlight how in countries where the asbestos ban has been active for over 20 years the risk of asbestos remains present, especially in the construction sector as well as for the environmental exposures of the resident population near companies that used asbestos in their production cycle. Worldwide, it is necessary to introduce the ban on the extraction, processing, and marketing of asbestos as claimed by the international scientific community.

Prevention of Asbestos Exposure in Latin America within a Global Public Health Perspective

BACKGROUND

Asbestos consumption in Latin America (LA) amounts to 10% of yearly global production. Little is known about the impact of asbestos exposure in the region.

OBJECTIVE

To discuss scientific and socio-economic issues and conflicts of interest and to summarize epidemiological data of asbestos health effects in LA.

DISCUSSION

Recent data on chrysotile strengthened the evidence of its carcinogenicity and showed an excessive risk of lung cancer at cumulative exposure levels as low as 1.5 fibre-years/ml. Technology for substitution is available for all asbestos-containing products and ceasing asbestos production and manufacturing will not result in unemployment and loss of income, except for the mining industry. The flawed arguments used by the industry to maintain its market, both to the public and in courtrooms, strongly relies on the lack of local evidence of the ill effects and on the invisibility of asbestos-related diseases in LA, due to the limited number of studies and the exposed workers' difficulty accessing health services. The few epidemiological studies available show clear evidence of clusters of mesothelioma in municipalities with a history of asbestos consumption and a forecasted rise in its incidence in Argentina and Brazil for the next decade. In Brazil, non-governmental organizations of asbestos workers were pivotal to counterbalance misinformation and inequities, ending recently in a Supreme Court decision backing an asbestos ban. In parallel, continuous efforts should be made to stimulate the growth of competent and ethical researchers to convey adequate information to the scientific community and to the general public.

The Effect of pH and Biogenic Ligands on the Weathering of Chrysotile Asbestos: The Pivotal Role of Tetrahedral Fe in Dissolution Kinetics and Radical Formation

Chrysotile asbestos is a soil pollutant in many countries. It is a carcinogenic mineral, partly due to its surface chemistry. In chrysotile, FeII and FeIII substitute Mg octahedra (Fe[6]), and FeIII substitutes Si tetrahedra (Fe[4]). Fe on fiber surfaces can generate hydroxyl radicals (HO. ) in Fenton reactions, which damage biomolecules. To better understand chrysotile weathering in soils, net Mg and Si dissolution rates over the pH range 3.0-11.5 were determined in the presence and absence of biogenic ligands. Also, HO. generation and Fe bulk speciation of pristine and weathered fibers were examined by EPR and Mössbauer spectroscopy. Dissolution rates were increased by ligands and inversely related to pH with complete inhibition at cement pH (11.5). Surface-exposed Mg layers readily dissolved at low pH, but only after days at neutral pH. On longer timescales, the slow dissolution of Si layers became rate-determining. In the absence of ligands, Fe[6] precipitated as Fenton-inactive Fe phases, whereas Fe[4] (7 % of bulk Fe) remained redox-active throughout two-week experiments and at pH 7.5 generated 50±10 % of the HO. yield of Fe[6] at pristine fiber surfaces. Ligand-promoted dissolution of Fe[4] (and potentially Al[4]) labilized exposed Si layers. This increased Si and Mg dissolution rates and lowered HO. generation to near-background level. It is concluded that Fe[4] surface species control long-term HO. generation and dissolution rates of chrysotile at natural soil pH.

Characteristics and long-term outcomes of advanced pleural mesothelioma in Latin America (MeSO-CLICaP)

Background

Malignant pleural mesothelioma (MPM) is an aggressive tumor, associated with poor prognosis. There is a lack of information about the clinical and pathological features related with survival in the Latin American population.

Methods

The MeSO‐CLICaP registry identified 302 patients with advanced MPM diagnosed and treated between January 2008 and March 2016. The Cox model was applied to determine the variables associated with survival. A random forest tree model was built to predict the response to first‐line chemotherapy among Latin American patients.

Results

The median age was 61.1 years (SD 10.6 years), 191 (63.2%) were men, 65.9% were ever smokers, and 38.7% had previous exposure to asbestos. A total of 237 (78.5%) had epithelioid tumors, and 188 (62.3%) and 114 (37.7%) cases had stage III or IV MPM, respectively. A total of 49 patients (16.2%) underwent pleurectomy, 57 (18.9%) received radiotherapy, and 279 patients received first‐line platinum‐based chemotherapy. The overall response rate to first‐line chemotherapy was 40.4%, progression‐free survival to first‐line treatment was 5.7 months (95% CI 4.9–6.5), and 63 (20.8%) patients had pemetrexed maintenance. The median overall survival was 16.8 months (95% CI 13.0–20.5), and multivariate analysis found that stage (P = 0.013), and pleurodesis (P = 0.048), were independent prognostic factors for first‐line overall survival. The model to predict response to first‐line chemotherapy obtained a 0.98 area under the curve, a sensitivity of 93%, and a specificity of 95% for detecting responders and non‐responders.

Conclusion

This study identifies factors associated with clinical benefit from chemotherapy among advanced MPM Latin American patients, emphasizing the impact of histology and the clinical benefit of chemotherapy on outcomes.

BAP1 gene mutations in Egyptian patients with advanced sporadic malignant pleural mesothelioma (MPM): relation with clinical outcomes and survival

BACKGROUND

Malignant Pleural Mesothelioma (MPM) is a lethal cancer with few therapeutic options. Patients with MPM have a poor prognosis, with estimated 1 year median survival and currently no treatment is curative. The BRCA associated protein 1 (BAP1) has the highest prevalence of protein-altering mutations identified in MPM.

AIMS

Assessment of the frequency and pattern of BAP1 gene mutations in Egyptian patients with advanced sporadic MPM in relation to disease progression and survival rates in order to identify a novel therapeutic target for MPM.

METHODS

This prospective, cohort study included 122 patients who were diagnosed and treated as advanced MPM. BAP1 gene mutations were assessed from circulating tumor cells (CTCs) by polymerase chain reaction (PCR) and sequencing and these mutations have been confirmed using the tumor tissue. BAP1 immunohistochemistry was performed using the Dako Envision visualization system. The relationship between BAP1 gene mutations, PFS and OS rates was assessed using the log rank test. The relationship between BAP1 gene mutations, clinical response and patient's clinicopathological characteristics was assessed using chi-square test.

RESULTS

Forty seven (38.5%) MPM cases showed one or more mutations in BAP1 gene. The presence of BAP1 mutations associated significantly with BAP1 protein expression (p < 0.001), the incidence of organ metastasis (p = 0.04), PFS after second line treatment (p = 0.04) and clinical response after second line treatment (p = 0.01) only.

CONCLUSION

BAP1 gene mutations are relatively common in Egyptian patients with advanced sporadic MPM. BAP1 mutations are associated with disease progression especially after second line therapy and the incidence of organ metastasis.

Upcoming epidemic of asbestos-related malignant pleural mesothelioma in Taiwan: A prediction of incidence in the next 30 years

BACKGROUND/PURPOSE

Globally, asbestos-related diseases (ARDs) keep rising over the coming decades. The epidemic of ARDs will be a burden on public health. We aimed to predict the malignant pleural mesothelioma (MPM) incidence in the next 30 years for Taiwan based on historical asbestos consumption.

METHODS

We collected annual data on local asbestos consumption during 1939-2015 and sex-specific incidence of pleural cancer as a proxy for MPM during 1979-2013. We applied Poisson log-linear models to predict future MPM numbers under the assumption that latency periods between asbestos exposure and MPM incidence were between 25 and 45 years.

RESULTS

Asbestos consumption reached a peak in the 1980s, with a total of 668 thousand metric tons during 1939-2015. The observed number of MPM incidence increased by 9- and 6-fold in males and females during 1979-2013, with a cumulative number of 907. Given a latency period of 31 years, MPM incidences were expected to peak around 2012-2016 for males and 2016-2020 for females. In 2017-2046, the predicted total number of new MPM might reach 659 cases (95% confidence interval = 579-749); and the male to female ratios ranged from 1.8 to 2.8.

CONCLUSION

The MPM epidemic in Taiwan will likely peak in 2012-2020 as a result of local asbestos consumption. Approximately 659 new MPM cases in the next 30 years warrant an urgent need to implement a total asbestos ban and put more resources on a comprehensive surveillance, diagnosis, and follow-up health care system for ARDs.

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.

Diagnostic value of microRNAs in asbestos exposure and malignant mesothelioma: systematic review and qualitative meta-analysis

Background

Asbestos is a harmful and exceptionally persistent natural material. Malignant mesothelioma (MM), an asbestos-related disease, is an insidious, lethal cancer that is poorly responsive to current treatments. Minimally invasive, specific, and sensitive biomarkers providing early and effective diagnosis in high-risk patients are urgently needed. MicroRNAs (miRNAs, miRs) are endogenous, non-coding, small RNAs with established diagnostic value in cancer and pollution exposure. A systematic review and a qualitative meta-analysis were conducted to identify high-confidence miRNAs that can serve as biomarkers of asbestos exposure and MM.

Methods

The major biomedical databases were systematically searched for miRNA expression signatures related to asbestos exposure and MM. The qualitative meta-analysis applied a novel vote-counting method that takes into account multiple parameters. The most significant miRNAs thus identified were then subjected to functional and bioinformatic analysis to assess their biomarker potential.

Results

A pool of deregulated circulating and tissue miRNAs with biomarker potential for MM was identified and designated as “mesomiRs” (MM-associated miRNAs). Comparison of data from asbestos-exposed and MM subjects found that the most promising candidates for a multimarker signature were circulating miR-126-3p, miR-103a-3p, and miR-625-3p in combination with mesothelin. The most consistently described tissue miRNAs, miR-16-5p, miR-126-3p, miR-143-3p, miR-145-5p, miR-192-5p, miR-193a-3p, miR-200b-3p, miR-203a-3p, and miR-652-3p, were also found to provide a diagnostic signature and should be further investigated as possible therapeutic targets.

Conclusion

The qualitative meta-analysis and functional investigation confirmed the early diagnostic value of two miRNA signatures for MM. Large-scale, standardized validation studies are needed to assess their clinical relevance, so as to move from the workbench to the clinic.

An Overview of Asbestos and Malignant Pleural Mesothelioma: An Iranian Perspective

Asbestos refers to a group of minerals that appears naturally in the environment as bundles of fibers. The incidence rate of asbestos-related diseases has considerably increased as well as the amount of asbestos utilization in few countries. Malignant pleural mesothelioma (MPM) is a rare type of aggressive and life threatening neoplasm which arise from various serous surfaces: pleura, peritoneum, tunica vaginalis and pericardium. The first case of MPM was reported in 1947. MPM etiologically is associated to the exposure of asbestos fibers. This form of malignancy is difficult to diagnose in paraclinical work-ups because mesothelioma could occur within 10-20 years of the first-time exposure to asbestos. The burden of MPM is not yet to be wholly understood. The toxic side effects of asbestos on environment and people compelled the European countries to accept the French view upon this matter. However, this approach has not been accepted by some developing countries. This review provides a brief points and facts in relation to MPM and asbestos in Iran.

Novel systemic therapy against malignant pleural mesothelioma

Malignant pleural mesothelioma is an aggressive tumor of the pleura with an overall poor prognosis. Even with surgical resection, for which only a subset of patients are eligible, long term disease free survival is rare. Standard first-line systemic treatment consists of a platinum analog, an anti-metabolite, and sometimes anti-angiogenic therapy, but there is currently no well-established standard therapy for refractory or relapsed disease. This review focuses on efforts to develop improved systemic therapy for the treatment of malignant pleural mesothelioma (MPM) including cytotoxic systemic therapy, a variety of tyrosine kinase inhibitors and their downstream effector pathways, pharmacologic targeting of the epigenome, novel approaches to target proteins expressed on mesothelioma cells (such as mesothelin), arginine depletion therapy, and the emerging role of immunotherapy. Overall, these studies demonstrate the challenges of improving systemic therapy for MPM and highlight the need to develop therapeutic strategies to control this disease.

Mortalidad por mesotelioma en Argentina, 1980-2013

Se estimó la tasa de mortalidad por mesotelioma y su distribución sociodemográfica y temporal en Argentina para el período 1980-2013 con datos del Sistema de Estadísticas Vitales del Ministerio de Salud de la Nación. Se encontraron 3.259 defunciones por mesotelioma, lo que resulta en una tasa de mortalidad estandarizada por edad de 3,1/1.000.000 en 1980 y de 5,7/1.000.000 en 2013, con un aumento promedio del 84,1% en 34 años. El incremento de la tendencia fue más claro a partir de 1997. En todos los años, la tasa de mortalidad fue mayor en hombres que en mujeres. Los resultados sugieren antecedentes de exposición al asbesto en el pasado. Aparentemente, la exposición predominante fue la ocupacional, más común entre los hombres que concentraron los casos. Se recomiendan acciones dirigidas a hacer más efectiva la prohibición ya en vigor y la vigilancia en salud orientada a los ambientes de trabajo, trabajadores previamente expuestos y la población en general.

Transformation of the released asbestos, carbon fibers and carbon nanotubes from composite materials and the changes of their potential health impacts

Composite materials with fibrous reinforcement often provide superior mechanical, thermal, electrical and optical properties than the matrix. Asbestos, carbon fibers and carbon nanotubes (CNTs) have been widely used in composites with profound impacts not only on technology and economy but also on human health and environment. A large number of studies have been dedicated to the release of fibrous particles from composites. Here we focus on the transformation of the fibrous fillers after their release, especially the change of the properties essential for the health impacts. Asbestos fibers exist in a large number of products and the end-of-the-life treatment of asbestos-containing materials poses potential risks. Thermal treatment can transform asbestos to non-hazardous phase which provides opportunities of safe disposal of asbestos-containing materials by incineration, but challenges still exist. Carbon fibers with diameters in the range of 5–10 μm are not considered to be respirable, however, during the release process from composites, the carbon fibers may be split along the fiber axis, generating smaller and respirable fibers. CNTs may be exposed on the surface of the composites or released as free standing fibers, which have lengths shorter than the original ones. CNTs have high thermal stability and may be exposed after thermal treatment of the composites and still keep their structural integrity. Due to the transformation of the fibrous fillers during the release process, their toxicity may be significantly different from the virgin fibers, which should be taken into account in the risk assessment of fiber-containing composites.

Developing Asbestos Job Exposure Matrix Using Occupation and Industry Specific Exposure Data (1984-2008) in Republic of Korea

Background

The goal of this study is to develop a general population job-exposure matrix (GPJEM) on asbestos to estimate occupational asbestos exposure levels in the Republic of Korea.

Methods

Three Korean domestic quantitative exposure datasets collected from 1984 to 2008 were used to build the GPJEM. Exposure groups in collected data were reclassified based on the current Korean Standard Industrial Classification (9^th edition) and the Korean Standard Classification of Occupations code (6^th edition) that is in accordance to international standards. All of the exposure levels were expressed by weighted arithmetic mean (WAM) and minimum and maximum concentrations.

Results

Based on the established GPJEM, the 112 exposure groups could be reclassified into 86 industries and 74 occupations. In the 1980s, the highest exposure levels were estimated in “knitting and weaving machine operators” with a WAM concentration of 7.48 fibers/mL (f/mL); in the 1990s, “plastic products production machine operators” with 5.12 f/mL, and in the 2000s “detergents production machine operators” handling talc containing asbestos with 2.45 f/mL. Of the 112 exposure groups, 44 groups had higher WAM concentrations than the Korean occupational exposure limit of 0.1 f/mL.

Conclusion

The newly constructed GPJEM which is generated from actual domestic quantitative exposure data could be useful in evaluating historical exposure levels to asbestos and could contribute to improved prediction of asbestos-related diseases among Koreans.

Current and future risks of asbestos exposure in the Australian community

BACKGROUND

Australia mined asbestos for more than 100 years and manufactured and imported asbestos products. There is a legacy of in situ asbestos throughout the built environment.

METHODS

The aim of this study was to identify the possible sources of current and future asbestos exposure from the built environment. Telephone interviews with environmental health officers, asbestos removalists, and asbestos assessors in Australia sought information about common asbestos scenarios encountered.

RESULTS

There is a considerable amount of asbestos remaining in situ in the Australian built environment. Potential current and future sources of asbestos exposure to the public are from asbestos-containing roofs and fences, unsafe asbestos removal practices, do-it-yourself home renovations and illegal dumping.

CONCLUSION

This research has highlighted a need for consistent approaches in the regulation and enforcement of safe practices for the management and removal of asbestos to ensure that in situ asbestos in the built environment is managed appropriately.

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.

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.

Environmental risk of mesothelioma in the United States: An emerging concern-epidemiological issues

Despite predictions of decline in mesothelioma following the ban of asbestos in most industrial countries, the incidence is still increasing globally, particularly in women. Because occupational exposure to asbestos is the main cause of mesothelioma, it occurs four- to eightfold more frequently in men than women, at a median age of 74 years. When mesothelioma is due to an environmental exposure, the M:F sex ratio is 1:1 and the median age at diagnosis is ~60 years. Studying environmental risk of mesothelioma is challenging because of the long latency period and small numbers, and because this type of exposure is involuntary and unknown. Individual-based methods cannot be used, and new approaches need to be found. To better understand the most recent trends of mesothelioma in the United States, all mesothelioma deaths reported to the Centers for Disease Control and Prevention (CDC) during 1999-2010 were analyzed. Among all mesothelioma deaths in the United States, the 1920s birth cohort significantly predominated, and the proportion of younger cohorts constantly decreased with time, suggesting a decline in occupational exposure in these cohorts. The M:F mesothelioma sex ratio fell with time, suggesting an increased proportion of environmental cases. Environmental exposures occur in specific geographic areas. At the large scale of a state, mesotheliomas related to environmental exposure are diluted among occupational cases. The spatial analysis at a smaller scale, such as county, enables detection of areas with higher proportions of female and young mesothelioma cases, thus indicating possible environmental exposure, where geological and environmental investigations need to be carried out.

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.

Occupational and environmental exposures and cancers in developing countries

BACKGROUND

Over the past few decades, there has been a decline in cancers attributable to environmental and occupational carcinogens of asbestos, arsenic, and indoor and outdoor air pollution in high-income countries. For low- to middle-income countries (LMICs), however, these exposures are likely to increase as industrialization expands and populations grow.

OBJECTIVE

The aim of this study was to review the evidence on the cancer risks and burdens of selected environmental and occupational exposures in less-developed economies.

FINDINGS

A causal association has been established between asbestos exposure and mesothelioma and lung cancer. For arsenic exposure, there is strong evidence of bladder, skin, lung, liver, and kidney cancer effects. Women are at the highest risk for lung cancer due to indoor air pollution exposure; however, the carcinogenic effect on the risk for cancer in children has not been studied in these countries. Cancer risks associated with ambient air pollution remain the least studied in LMICs, although reported exposures are higher than World Health Organization, European, and US standards. Although some associations between lung cancer and ambient air pollutants have been reported, studies in LMICs are weak or subject to exposure misclassification. For pulmonary cancers, tobacco smoking and respiratory diseases have a positive synergistic effect on cancer risks.

CONCLUSIONS

A precise quantification of the burden of human cancer attributable to environmental and occupational exposures in LMICs is uncertain. Although the prevalence of carcinogenic exposures has been reported to be high in many such countries, the effects of the exposures have not been studied due to varying country-specific limitations, some of which include lack of resources and government support.

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.

Incidence of malignant mesothelioma of the pleura in Québec and Canada from 1984 to 2007, and projections from 2008 to 2032

BACKGROUND

Continuous increase in male incidence of malignant mesothelioma of the pleura (MMP) despite the drop of asbestos production since 1980 in Québec motivated this study aiming to assess when the rates of MMP will decline.

METHODS

Age-standardized rates and trends were estimated over the 1984-2007 period by sex for Québec versus "Canada-excluding-Québec" (Can-Qc). An age-cohort regression was used to make projections for 2008-2032.

RESULTS

Average rates of MMP in Québec men and women were significantly higher than in Can-Qc. Projected rates peak between 2003 and 2012 in all four study populations and decline thereafter.

CONCLUSION

The higher MMP rates and observed/projected time patterns in Québec men are consistent with past asbestos production and occupational exposures. The excess in Québec women may also be explained by domestic and, for some, by neighborhood exposures. To pursue the decrease in MMP rates beyond 2032, efforts to reduce asbestos exposure should be maintained.

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.

Mesothelioma in occupational cohort studies: methodological considerations

OBJECTIVE

This article describes effective strategies for the identification and valid assessment of mortality due to mesothelioma.

METHODS

We manually reviewed all death certificates for mention of mesothelioma for all International Classification of Diseases (ICD) revisions. We tested the accuracy of our ascertainment method by comparing New Jersey death certificate data from our health status registry with histologically confirmed cases from the New Jersey State Cancer Registry.

RESULTS

We found reasonably good agreement between death certificate diagnoses and histologically confirmed cases, κ coefficient 0.86 (95% confidence interval, 0.76 to 0.95). Most mesothelioma deaths in our test and North American cohorts were coded to unspecified anatomical sites.

CONCLUSIONS

Limiting ascertainment to pleura and peritoneum ICD codes underestimates mesothelioma deaths. Reviewing all ICD codes that could contain mesothelioma is the only effective method for complete capture of mesothelioma diagnoses.

Designing hybrid onconase nanocarriers for mesothelioma therapy: a Taguchi orthogonal array and multivariate component driven analysis

Onconase (ONC) is a member of a ribonuclease superfamily that has cytostatic activity against malignant mesothelioma (MM). The objective of this investigation was to develop bovine serum albumin (BSA)-chitosan based hybrid nanoformulations for the efficient delivery of ONC to MM while minimizing the exposure to normal tissues. Taguchi orthogonal array L9 type design was used to formulate ONC loaded BSA nanocarriers (ONC-ANC) with a mean particle size of 15.78 ± 0.24 nm (ζ = -21.89 ± 0.11 mV). The ONC-ANC surface was hybridized using varying chitosan concentrations ranging between 0.100 and 0.175% w/v to form various ONC loaded hybrid nanocarriers (ONC-HNC). The obtained data set was analyzed by principal component analysis (PCA) and principal component regressions (PCR) to decode the effects of investigated design variables. PCA showed positive correlations between investigated design variables like BSA, ethanol dilution, and total ethanol with particle size and entrapment efficiency (EE) of formulated nanocarriers. PCR showed that the particle size depends on BSA, ethanol dilution, and total ethanol content, while EE was only influenced by BSA content. Further analysis of chitosan and TPP effects used for coating of ONC-ANC by PCR confirmed their positive impacts on the particle size, zeta potential, and prolongation of ONC release compared to uncoated ONC-ANC. PCR analysis of preliminary stability studies showed increase in the particle size and zeta potential at lower pH. However, particle size, zeta potential, and EE of developed HNC were below 63 nm, 31 mV, and 96%, respectively, indicating their stability under subjected buffer conditions. Out of the developed formulations, HNC showed enhanced inhibition of cell viability with lower IC50 against human MM-REN cells compared to ONC and ONC-ANC. This might be attributed to the better cell uptake of HNC, which was confirmed in the cell uptake fluorescence studies. These studies indicated that a developed nanotherapeutic approach might aid in reducing the therapeutic dose of ONC, minimizing adverse effects by limiting the exposure of ONC to normal tissues, and help in the development of new therapeutic forms and routes of administration.

The wild rat as sentinel animal in the environmental risk assessment of asbestos pollution: a pilot study

Asbestos has been banned in many countries, including Italy. However, sources of exposure may still exist, due to asbestos in-situ or past disposal of asbestos-containing waste. In an urban area with past high environmental exposure, like Casale Monferrato, the lung fiber burden in sentinel animals may be useful to identify such sources. A pilot study was conducted to assess the feasibility of its determination in wild rats, a suitable sentinel species never used before for environmental lung asbestos fiber burden studies. Within the framework of pest control campaigns, 11 adult animals from 3 sites in the urban area of Casale Monferrato and 3 control rats from a different, unexposed town were captured. Further, 3 positive and 3 negative control lung samples were obtained from laboratories involved in breeding programs and conducting experimental studies on rats. Tissue fiber concentration was measured by scanning electron microscopy with energy dispersive spectrometry. Asbestos (chrysotile and crocidolite) was identified in the lungs from rats from Casale Monferrato, but not in control rats and in negative control lung samples. Asbestos grunerite at high concentration was found in positive control lung samples. Measurement of the lung fiber burden in wild rats has proved feasible: it was possible not only to detect, but also to characterize asbestos fibers both qualitatively and quantitatively. The pilot study provides the rationale for using wild rats as sentinels of the soil contamination level in Casale Monferrato, to identify areas with the possible presence of previously unrecognized asbestos sources.

Curcumin: a double hit on malignant mesothelioma

Inflammation is a key mediator in the development of malignant mesothelioma, which has a dismal prognosis and poor therapeutic strategies. Curcumin, a naturally occurring polyphenol in turmeric, has been shown to possess anticarcinogenic properties through its anti-inflammatory effects. Inflammasomes, a component of inflammation, control the activation of caspase-1 leading to pyroptosis and processing of proinflammatory cytokines, interleukin (IL)-1β and IL-18. In the present study, we investigate the role of curcumin in pyroptotic cell death of malignant mesothelioma cells. Using in vitro models with mouse and human malignant mesothelioma cells, curcumin is shown to induce pyroptosis through activation of caspase-1 and increased release of high-mobility group box 1 (HMGB1) without processing of IL-1β and IL-18. Absence of IL-1β processing in response to curcumin-mediated caspase-1 activation is attributed to blockade of pro-IL-1β priming through inhibition of the NF-κB pathway. Furthermore, curcumin's cytotoxicity in malignant mesothelioma cells is demonstrated to be dependent on pyroptosis as inhibition of caspase-1 resulted in protection against curcumin-induced cell death. We also demonstrate that curcumin-mediated caspase-1 activation is oxidant dependent by using N-acetyl-L-cysteine (NAC) to inhibit pyroptosis. PCR array analysis using the human inflammasome template revealed that curcumin significantly downregulated levels of inflammasome-related gene expression involved in inflammation, e.g., NF-κB, toll-like receptors (TLR), and IL-1β. Our data indicate that curcumin has a double effect on malignant mesothelioma cells through induction of pyroptosis while subsequently protecting against inflammation.

Global estimates of the burden of injury and illness at work in 2012

This article reviews the present indicators, trends, and recent solutions and strategies to tackle major global and country problems in safety and health at work. The article is based on the Yant Award Lecture of the American Industrial Hygiene Association (AIHA) at its 2013 Congress. We reviewed employment figures, mortality rates, occupational burden of disease and injuries, reported accidents, surveys on self-reported occupational illnesses and injuries, attributable fractions, national economic cost estimates of work-related injuries and ill health, and the most recent information on the problems from published papers, documents, and electronic data sources of international and regional organizations, in particular the International Labor Organization (ILO), World Health Organization (WHO), and European Union (EU), institutions, agencies, and public websites. We identified and analyzed successful solutions, programs, and strategies to reduce the work-related negative outcomes at various levels. Work-related illnesses that have a long latency period and are linked to ageing are clearly on the increase, while the number of occupational injuries has gone down in industrialized countries thanks to both better prevention and structural changes. We have estimated that globally there are 2.3 million deaths annually for reasons attributed to work. The biggest component is linked to work-related diseases, 2.0 million, and 0.3 million linked to occupational injuries. However, the division of these two factors varies depending on the level of development. In industrialized countries the share of deaths caused by occupational injuries and work-related communicable diseases is very low while non-communicable diseases are the overwhelming causes in those countries. Economic costs of work-related injury and illness vary between 1.8 and 6.0% of GDP in country estimates, the average being 4% according to the ILO. Singapore's economic costs were estimated to be equivalent to 3.2% of GDP based on a preliminary study. If economic losses would take into account involuntary early retirement then costs may be considerably higher, for example, in Finland up to 15% of GDP, while this estimate covers various disorders where work and working conditions may be just one factor of many or where work may aggravate the disease, injury, or disorders, such as traffic injuries, mental disorders, alcoholism, and genetically induced problems. Workplace health promotion, services, and safety and health management, however, may have a major preventive impact on those as well. Leadership and management at all levels, and engagement of workers are key issues in changing the workplace culture. Vision Zero is a useful concept and philosophy in gradually eliminating any harm at work. Legal and enforcement measures that themselves support companies and organizations need to be supplemented with economic justification and convincing arguments to reduce corner-cutting in risk management, and to avoid short- and long-term disabilities, premature retirement, and corporate closures due to mismanagement and poor and unsustainable work life. We consider that a new paradigm is needed where good work is not just considered a daily activity. We need to foster stable conditions and circumstances and sustainable work life where the objective is to maintain your health and work ability beyond the legal retirement age. We need safe and healthy work, for life.

Potential years of life lost (PYLL) caused by asbestos-related diseases in the world

BACKGROUND

We applied the well-established, but rather under-utilized, indicator of Potential Years of Life Lost (PYLL) to estimate the global burden of mesothelioma and asbestosis.

METHODS

We analyzed all deaths caused by mesothelioma and asbestosis that were reported by 82 and 55 countries, respectively, to the World Health Organization (WHO) from 1994 to 2010.

RESULTS

The 128,015 and 13,885 persons who died of mesothelioma and asbestosis, potentially lost a total of 2.18 million and 180,000 years of life (PYLL), or, an annual average PYLL of 201,000 years and 17,000 years, respectively. The average PYLL per decedent were 17.0 and 13.0 years for mesothelioma and asbestosis, respectively.

CONCLUSIONS

The current burden of asbestos-related diseases (ARDs) in terms of PYLL is substantial. The future burden of ARDs can be eliminated by stopping the use of asbestos.

Awareness of Asbestos and Action Plans for Its Exposure can Help Lives Exposed to Asbestos

Despite the fact that asbestos is a known carcinogen to humans, it is still used in industrialized countries, especially Asian countries. The global incidence of asbestos-related diseases (ARDs) due to the past use of asbestos, continues to increase, although many countries have adopted a total ban on asbestos use. The implementation of effective strategies to eliminate ARDs is therefore an important challenge in Asia, where asbestos is still mined and consumed. Collaborative efforts and strategies at the local and international levels are vital, in the pursuit toward the elimination of ARDs in this region.

Mesothelioma incidence in 50 states and the District of Columbia, United States, 2003-2008

BACKGROUND

The decline in asbestos use in the United States may impact mesothelioma incidence.

OBJECTIVE

This report provides national and state-specific estimates of mesothelioma incidence in the United States using cancer surveillance data for the entire US population.

METHODS

Data from the National Program for Cancer Registries and the Surveillance, Epidemiology, and End Results program were used to calculate incidence rates and annual percent change.

RESULTS

During 2003-2008, an average of 1.05 mesothelioma cases per 100 000 persons were diagnosed annually in the United States; the number of cases diagnosed each year remained level, whereas rates decreased among men and were stable among women.

CONCLUSION

US population-based cancer registry data can be used to determine the burden of mesothelioma and track its decline. Even 30 years after peak asbestos use in the United States, 3200 mesothelioma cases are diagnosed annually, showing that the US population is still at risk.

Malignant mesothelioma in Eastern Asia

Relatively low numbers of malignant mesotheliomas have been reported from Eastern Asia. In order to explore the causes of this fact, the available data on mesothelioma incidence/mortality in five countries (Japan, South Korea, Taiwan, Hong Kong, and Singapore) were reviewed. Data on the industrial histories of the above countries were also examined. Mesothelioma incidence was low, despite a history of high shipbuilding and port activities, in which heavy exposure to asbestos generally has occurred. Underestimation of mesothelioma could partly explain the above discrepancy. Moreover, in some areas a sufficient latency period for mesothelioma development may have not yet elapsed, due to recent industrialization. However, other possibilities have to be considered. The cancer epidemiology in Eastern Asia differs deeply from that seen in Western countries, an indication of differences in etiologic factors of cancer as well as in co-factors. In addition, the oncogenic spectrum of asbestos is wide, and not completely defined. In a very different milieu from that of Western countries, asbestos could preferentially hit targets other than serosal membranes.

Elimination of asbestos use and asbestos-related diseases: an unfinished story

Asbestos is a proven human carcinogen. Asbestos-related diseases (ARDs) typically comprise lung cancer, malignant mesothelioma, asbestosis, pleural plaques, thickening and effusion. International organizations, notably the World Health Organization and the International Labour Organization, have repeatedly declared the need to eliminate ARDs, and have called on countries to stop using asbestos. However, the relevant national-level indicators (e.g., incidence/mortality rates and per capita asbestos use, as well as their interrelationships) indicate that ARDs are increasing and asbestos use is continuing in the world. Lessons learned by industrialized countries in terms of policy and science have led to a growing number of countries adopting bans. In contrast, industrializing countries are faced with a myriad of forces prompting them to continue using asbestos. Full-scale international cooperation will thus be needed, with industrialized countries sharing their experiences and technologies to enable industrializing countries to make smooth transitions to banned states and achieve the goal of eliminating ARDs.

Mitochondria-derived reactive intermediate species mediate asbestos-induced genotoxicity and oxidative stress-responsive signaling pathways

BACKGROUND

The incidence of asbestos-induced human cancers is increasing worldwide, and considerable evidence suggests that reactive oxygen species (ROS) are important mediators of these diseases. Our previous studies suggested that mitochondria might be involved in the initiation of oxidative stress in asbestos-exposed mammalian cells.

OBJECTIVE

We investigated whether mitochondria are a potential cytoplasmic target of asbestos using a mitochondrial DNA-depleted (ρ(0)) human small airway epithelial (SAE) cell model: ρ(0) SAE cells lack the capacity to produce mitochondrial ROS.

METHODS

We examined nuclear DNA damage, micronuclei (MN), intracellular ROS production, and the expression of inflammation-related nuclear genes in both parental and ρ(0) SAE cells in response to asbestos treatment.

RESULTS

Asbestos induced a dose-dependent increase in nuclear DNA oxidative damage and MN in SAE cells. Furthermore, there was a significant increase in intracellular oxidant production and activation of genes involved in nuclear factor κB and proinflammatory signaling pathways in SAE cells. In contrast, the effects of asbestos were minimal in ρ(0) SAE cells.

CONCLUSIONS

Mitochondria are a major cytoplasmic target of asbestos. Asbestos may initiate mitochondria-associated ROS, which mediate asbestos-induced nuclear mutagenic events and inflammatory signaling pathways in exposed cells. These data provide new insights into the molecular mechanisms of asbestos-induced genotoxicity.

Industrial pollution and pleural cancer mortality in Spain

Pleural cancer mortality is an acknowledged indicator of exposure to asbestos and mesothelioma mortality but in 15%-20% of cases no exposure can be recalled. In the past, asbestos was used in many industries and it is still found in many installations. Our objective was to ascertain whether there might be excess pleural cancer mortality among populations residing in the vicinity of Spanish industrial installations that are governed by the Integrated Pollution Prevention and Control (IPPC) Directive and the European Pollutant Release and Transfer Register Regulation and report their emissions to air. An ecological study was designed to examine pleural cancer mortality at a municipal level (8098 Spanish towns) over the period 1997-2006, during which 2146 deaths were registered. We conducted an exploratory "near vs. far" analysis to estimate the relative risks (RRs) of towns situated at a distance of <2 km from installations. This analysis was repeated for each of the 24 industrial groups. RR and their 95% credible intervals (95% CIs) were estimated on the basis of a Poisson conditional autoregressive Bayesian model with explanatory variables. Integrated nested Laplace approximations were used as a Bayesian inference tool. Analysis showed statistically significant RRs in both sexes in the vicinity of 7 of the 24 industrial groups studied (RR, 95% CI), namely, biocide facilities (2.595, 1.459-4.621), ship-building (2.321, 1.379-3.918), glass and mineral fibre production (1.667, 1.041-2.665), non-hazardous waste treatment (1.737, 1.077-2.799), galvanising (1.637, 1.139-2.347), organic chemical plants (1.386, 1.075-1.782) and the food and beverage sector (1.255, 1.006-1.562). In the proximity of sources pertaining to the biocide, organic chemical and galvanising sectors, the risk was seen to be rising among men and women, a finding that could indicate airborne environmental exposure. These results support that residing in the vicinity of IPPC-registered industries that release pollutants to the air constitutes a risk factor for pleural cancer.

OccIDEAS: An Innovative Tool to Assess Past Asbestos Exposure in the Australian Mesothelioma Registry

Malignant mesothelioma is an uncommon but rapidly fatal disease for which the principal aetiological agent is exposure to asbestos. Mesothelioma is of particular significance in Australia where asbestos use was very widespread from the 1950s until the 1980s. Exposure to asbestos includes occupational exposure associated with working with asbestos or in workplaces where asbestos is used and also 'take-home' exposure of family members of asbestos exposed workers. Asbestos exposure may also be non-occupational, occurring as a consequence of using asbestos products in non-occupational contexts and passive exposure is also possible, such as exposure to asbestos products in the built environment or proximity to an environmental source of exposure, for example an asbestos production plant. The extremely long latency period for this disease makes exposure assessment problematic in the context of a mesothelioma registry. OccIDEAS, a recently developed online tool for retrospective exposure assessment, has been adapted for use in the Australian Mesothelioma Registry (AMR) to enable systematic retrospective exposure assessment of consenting cases. Twelve occupational questionnaire modules and one non-occupational module have been developed for the AMR, which form the basis of structured interviews using OccIDEAS, which also stores collected data and provides a framework for generating metrics of exposure.

Immunohistochemistry and Molecular Diagnostics of Pleural Malignant Mesothelioma

Context.—The pathologic approach to pleural-based lesions is stepwise and uses morphologic assessment, correlated with clinical and imaging data supplemented by immunohistochemistry (IHC), and more recently, molecular tests, as an aid for 2 main diagnostic problems: malignant mesothelioma (MM) versus other malignant tumors and malignant versus reactive mesothelial proliferations.

Objective.—To present the current knowledge regarding IHC and molecular tests with respect to MM diagnosis, and in particular, the differentiation of the epithelioid type of MM from carcinoma metastatic to the pleural cavity.

Data Sources.—A review of immunohistochemical features of 286 consecutive MMs from 459 cases of pleural pathology, diagnosed during routine practice from 2003 to 2009. A survey of biomedical journal literature from MedLine/PubMed (US National Library of Medicine) focused on MM and associated tissue-based diagnostic IHC markers and molecular tests.

Conclusions.—The search for a single diagnostic marker of MM has so far been discouraging, given the biologic and phenotypic tumor heterogeneity of MM. The use of antibody panels has gained unanimous acceptance especially in the differential diagnosis between MM and metastatic carcinoma, whereas the usefulness of IHC is more limited when dealing with spindle cell malignancies or distinguishing malignant from reactive mesothelium. A great degree of interlaboratory variability in antibody combinations and clone selection within diagnostic panels still exists. Current investigations aim at selecting the most suitable and cost-effective combination of antibodies by using novel statistical approaches for assessing diagnostic performance beyond the traditional measures of sensitivity and specificity.