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The presentations in this session of the Monticello II conference were aimed at summarizing what is known about asbestiform and non-asbestiform elongate mineral particles (EMPs) and mesothelioma risks based on evidence from experimental and epidemiology studies. Dr. Case discussed case reports of mesothelioma over the last several decades. Dr. Taioli indicated that the epidemiology evidence concerning non-asbestiform EMPs is weak or lacking, and that progress would be limited unless mesothelioma registries are established. One exception discussed is that of taconite miners, who are exposed to grunerite. Drs. Mandel and Odo noted that studies of taconite miners in Minnesota have revealed an excess rate of mesothelioma, but the role of non-asbestiform EMPs in this excess incidence of mesothelioma is unclear. Dr. Becich discussed the National Mesothelioma Virtual Bank (NMVB), a virtual mesothelioma patient registry that includes mesothelioma patients' lifetime work histories, exposure histories, biospecimens, proteogenomic information, and imaging data that can be used in epidemiology research on mesothelioma. Dr. Bernstein indicated that there is a strong consensus that long, highly durable respirable asbestiform EMPs have the potential to cause mesothelioma, but there is continued debate concerning the biodurability required, and the dimensions (both length and diameter), the shape, and the dose associated with mesothelioma risk. Finally, Dr. Nel discussed how experimental studies of High Aspect Ratio Engineered Nanomaterials have clarified dimensional and durability features that impact disease risk, the impact of inflammation and oxidative stress on the epigenetic regulation of tumor suppressor genes, and the generation of immune suppressive effects in the mesothelioma tumor microenvironment. The session ended with a discussion of future research needs.

The aim of this study is the reconstruction of asbestos exposure in absence of environmental monitoring data, to use the results in a cohort study of railway rolling stock workers.To reconstruct past exposures, the production data (number of rolling stock and asbestos content) and working methods were reconstructed with former employees and company documentation, literature data, and author expertise.The result of the work is a job/exposure matrix from 1956 to 1979, when sprayed asbestos was used as insulator of the metal bodies. Annual exposure estimate varies from 0.08 to 4.9 fb/mL depending on the specific jobs. Thirty-one mesotheliomas with occupational exposure, one with environmental and one with family exposures, were identified.The originality of the study consists on the use of company production data to establish frequency duration of asbestos exposure.

Malignant pleural mesothelioma is an asbestos-related disease with poor survival. The prognostic role of histologic subtype is well established. Some studies (without a biological hypothesis) suggested that higher asbestos lung burden is associated with reduced survival.We selected subjects from two series of necropsies: residents in Brescia province (North-West Italy) and workers (or persons living with them) employed in the Monfalcone shipyards (North-East Italy). Asbestos fibers and asbestos bodies in lung samples were counted using a scanning electron and an optical microscope, respectively. Separately in the two series, we analyzed median survival time and fitted multivariable Cox regression models (adjusted for sex, period and age at diagnosis, and histopatholocical diagnosis) to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for three levels of asbestos fiber counts (reference:1 million fibers/g of dry lung tissue).We analyzed 185 necropsies, 83 in Brescia and 102 in Monfalcone. Despite a much higher lung burden in Monfalcone patients, median survival was slightly shorter in Brescia (8.3 mo) than in Monfalcone (10.2 mo). In Brescia, medium (1.0-9.9) and high (10+) fiber burden HRs were 0.91 (95% CI: 0.54-1.53) and 1.23 (95% CI: 0.41-3.70), respectively. In Monfalcone, the corresponding HRs were 1.18 (95% CI: 0.59-2.35) and 1.63 (95% CI: 0.77-3.45), respectively.No relationship between asbestos lung burden and survival was found. Histologic subtype was the strongest prognostic determinant.

Breast cancer is the most common cancer among women worldwide. In Taiwan, workers exposed to any of 31 hazardous chemicals or carcinogens in the work environment are designated as especially exposed workers (EEWs) by Taiwan's Ministry of Labor. We assessed the risk of breast cancer in this nationwide female EEW cohort.We conducted a nationwide retrospective study of 4,774,295 workers combining data collected from Taiwan's Ministry of Labor's EEW database between 1997 and 2018 and Taiwan's Cancer Registry between 1997 and 2016. Standardized incidence ratios (SIRs) for women exposed to different hazards and breast cancer incidence rate ratios (IRRs) were calculated by Poisson regression, adjusting for age and duration of exposure.3248 female workers with breast cancer and 331,967 without breast cancer were included. The SIRs and adjusted IRRs were 1.27 (95% CI 1.18-1.35) and 1.31 (95% CI 1.21-1.42) for lead, 1.74 (95% CI 1.23-2.24) and 1.52 (95% CI 1.13-2.04) for 1,1,2,2-tetrachloroethane, 1.47 (95% CI 1.12-1.82) and 1.42 (95% CI 1.12-1.81) for trichloroethylene/tetrachloroethylene), 1.40 (95% CI 1.23-1.57) and 1.38 (95% CI 1.22-1.57) for benzene, and 2.07 (95% CI 1.06-3.09) and 1.80 (95% CI 1.10-2.94) for asbestos. The results remained similar when factoring in a 2- or 5-year latency period.This study found possible correlations between occupational exposure to lead, chlorinated solvents (such as 1,1,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene), benzene, and asbestos with breast cancer risk among female EEW, suggesting a need for regular screening for breast cancer for employees exposed to these special workplace hazards.

Localized malignant peritoneal mesothelioma is a rare tumor with limited information in the literature. In this study, we present our experience with 18 cases seen in our hospital over a period of 43 years (1978 to 2021). Patients' median age was 55 years (y) (range: 33 to 79 y) and most of them were Caucasians. Patients presented with abdominal pain (11), ascites and right leg swelling (1), abdominal mass (1), and as incidental finding (1). Thirty percent of patients reported asbestos exposure, and all patients with available information had family history of tumors; a third had personal history of tumors. Seventy-seven percent had some form of abdominopelvic surgery and/or inflammatory process. Most cases had microscopic features typically seen in malignant mesothelioma; however, some cases had confounding features such as signet-ring cells, spindle cells, clear cell changes, and adenomatoid tumor-like appearance. BAP-1 by immunohistochemistry was lost in 1/3 cases. Only 1 patient underwent genetic testing and had an MSH2 germline mutation. Homozygous deletion of CDKN2A by FISH was not found in 1 tested case, although next-generation sequencing identified a CDKN2A pathogenic mutation. 16/18 (88%) had surgical treatment, and some also received adjuvant chemotherapy. The mean overall survival (OS) of our patients was 80.4 months (95% confidence interval: 54.3-106.52); the 3-year OS was 79%, while the 5-year OS was 52.6%. Fifty-three percent of patients had recurrences and 20% had tumor progression. Although the limited sample precludes definitive conclusions, small tumor size, low-grade cytology, and low mitotic index appeared to be associated with an indolent behavior.

Although asbestos has been banned in Switzerland since 1989, diseases caused by asbestos are still present and increasing today. In Switzerland, per year, occupational exposure to asbestos is responsible for approximately 135 deaths from mesothelioma and 930 deaths from lung cancer, though the latter is rarely recognized as an occupational disease. Taking an occupational history is essential for all such diagnosis, especially in smokers, whose risk of lung cancer increases due to the synergistic effect of asbestos and tobacco exposure. The medical practitioner can play an important role in occupational diseases being recognized as such, which is essential for the reimbursement of medical expenses by the accident insurance companies and the allocation of indemnities and pensions for the patient or their family.

Inhalation of asbestos fibers can cause malignant mesothelioma, a rapidly progressing and lethal cancer of the mesothelium, the thin layer of tissues surrounding internal organs in the chest and abdomen. Patients with malignant mesothelioma have a poor prognosis, with a median survival of 1 year from diagnosis. The estimated median interval from initial occupational asbestos exposure to death is 32 years (range = 13-70 years) (1). Occupational asbestos exposure is most often reported in men working in industries such as construction and manufacturing; however, women are also at risk for exposure to asbestos fibers, and limited data exist on longer-term trends in mesothelioma deaths among women. To characterize deaths associated with mesothelioma and temporal trends in mesothelioma mortality among women in the United States, CDC analyzed annual Multiple Cause of Death records from the National Vital Statistics System for 1999-2020, the most recent years for which complete data are available. The annual number of mesothelioma deaths among women increased significantly, from 489 in 1999 to 614 in 2020; however, the age-adjusted death rate per 1 million women declined significantly, from 4.83 in 1999 to 4.15 in 2020. The largest number of deaths was associated with the health care and social assistance industry (89; 15.7%) and homemaker occupation (129; 22.8%). Efforts to limit exposure to asbestos fibers, including among women, need to be maintained.

To understand the geographic distribution of and area-level factors associated with malignant mesothelioma incidence and survival in Australia.Generalised linear models and Bayesian spatial models were fitted using population registry data. Area-level covariates were socioeconomic quintile, remoteness category and state or territory. The maximised excess events test was used to test for spatial heterogeneity.There was strong evidence of spatial differences in standardised incidence rates for malignant mesothelioma but survival was uniformly poor. Incidence rates varied by state or territory and were lower in remote areas. Patterns in the geographic distribution of modelled incidence counts for malignant mesothelioma differed substantially from patterns of standardised incidence rates.Geographic variation in the modelled incidence counts of malignant mesothelioma demonstrates varying demand for diagnostic and management services. The long latency period for this cancer coupled with migration complicates any associations with patterns of exposure, however some of the geographic distribution of diagnoses can be explained by the location of historical mines and asbestos-related industries.

Historically, mesothelioma, which is almost exclusively a cancer of the pleura or peritoneum, has been referred to as a sentinel disease for asbestos exposure meaning that the disease is an epidemiologic marker for asbestos. This description of mesothelioma often has been misinterpreted to mean that the only risk factor for mesothelioma is asbestos. In addition to a few risk factors other than asbestos, in the US, background mesotheliomas, i.e. mesothelioma cases that are a consequence of spontaneous tumor formation, are the most prevalent number of cases after asbestos-associated cases.

Occupational asbestos exposure was prevalent in Taiwan, but asbestos-related diseases (ARDs) have rarely been recognized. We conducted in-depth face-to-face interviews with 16 patients with ARDs. All of them had worked in industries known for high asbestos exposure. However, only three patients had filed workers’ compensation (WC) claims, and of them, only two patients were approved. Reasons for the low compensation rate of ARDs could be divided into institutional barriers related to the flaws of the WC system and non-institutional barriers related to the knowledge status, causal interpretation, and social situations of individual workers. The Labor Occupational Accident Insurance and Protection Act passed in April 2021 has responded to the under-compensation of occupational diseases. However, the new act's effects toward improving the recognition of ARDs remain questionable. Our findings indicated that additional efforts are needed to remove non-institutional barriers hindering workers’ ability to ensure their compensation rights.

BACKGROUND: Pleural mesothelioma is a deadly asbestos induced cancer. Less than 10% of mesothelioma patients survive 5 years post diagnosis. However survival can range from a few months to a number of years. Accurate prediction of survival is important for patients to plan for their remaining life, and for clinicians to determine appropriate therapy. One unusual feature of mesothelioma is that patients frequently present with tumor-associated pleural effusions early in the course of the disease. OBJECTIVE: To study whether cells and molecules present in pleural effusions provide prognostic information for mesothelioma. METHODS: We profiled the cellular constituents and concentrations of 40 cytokines, chemokines and cellular factors (collectively “soluble factors”) involved in inflammatory and immune signalling pathways in pleural effusion samples from 50 mesothelioma patients. Associations with survival were evaluated by Cox proportional hazards regression methods. Results for the two soluble factors most significantly and independently associated with survival were validated in an independent set of samples (n= 51) using a separate assay system. RESULTS: Survival analysis revealed that IL8, IL2Ra (CD25) and PF4 were independent determinants of a more negative prognosis in mesothelioma patients, independent of other known prognostic factors. Lipocalin2 and IL4 were associated with better prognosis. CONCLUSIONS: This study demonstrates that pleural effusions rich in a range of soluble factors are associated with poor prognosis. These findings will enhance our ability to prognosticate outcomes in mesothelioma patients.

The potential toxic effects of short chrysotile and amphibole asbestos fibers with lengths5 to ∼10 µm have been debated over the years. This stems from the large database of epidemiology, toxicology, and

Asbestos fibers have been used as an industrial and construction material worldwide due to their high durability and low production cost. Commercial usage of asbestos is currently prohibited in Japan; however, the risk of asbestos-induced malignant mesothelioma (MM) remains. According to epidemiological data, the onset of MM is estimated to occur after a latent period of 30-40 years from initial exposure to asbestos fibers; thus, the continuous increase in MM is a concern. To explore the molecular mechanisms of MM using animal models, iron saccharate with iron chelator-induced sarcomatoid mesothelioma (SM) revealed hallmarks of homozygous deletion of Cdkn2a/2b by aCGH and microRNA-199/214 by expression microarray. Oral treatment of iron chelation by deferasirox decreased the rate of high-grade SM. Moreover, phlebotomy delayed MM development in crocidolite-induced MM in rats. In Divalent metal transporter 1 (Dmt1) transgenic mice, MM development was delayed because of low reactive oxygen species (ROS) production. These results indicate the importance of iron and ROS in mesothelial carcinogenesis. The aims of this review focus on the pathogenesis of elongated mineral particles (EMPs), including asbestos fibers and multiwalled carbon nanotubes (MWCNTs) that share similar rod-like shapes in addition to the molecular mechanisms of MM development.

Notwithstanding the ban in 1992, asbestos exposure for workers in the construction sector in Italy remains a concern. The purpose of this study is to describe the characteristics of malignant mesothelioma (MM) cases recorded by the Italian registry (ReNaM) among construction workers. Incident mesothelioma cases with a definite asbestos exposure have been analyzed. Characteristics of cases and territorial clusters of crude rates of MM in construction workers have been described, as well as the relation between asbestos use before the ban and the historical trend of workforce in the construction sector in Italy. ReNaM has collected 31,572 incident MM cases in the period from 1993 to 2018 and asbestos exposure has been assessed for 24,864 (78.2%) cases. An occupational exposure has been reported for 17,191 MM cases (69.1% of subjects with a definite asbestos exposure). Among them, 3574 had worked in the construction sector, with an increasing trend from 15.8% in the 1993–98 period to 23.9% in 2014–2018 and a ubiquitous territorial distribution. The large use of asbestos in construction sector before the ban makes probability of exposure for workers a real concern still today, particularly for those working in maintenance and removal of old buildings. There is a clear need to assess, inform, and prevent asbestos exposure in this sector.

Background Malignant pleural mesothelioma (MPM) is a rare but fatal cancer, which is largely caused by exposure to asbestos. Reliable information about the incidence of MPM prior the influence of asbestos is lacking. The nationwide regional incidence trends for MPM remain poorly characterized. We use nationwide MPM data for Denmark (DK), Finland (FI), Norway (NO) and Sweden (SE) to assess incidence, mortality and survival trends for MPM in these countries. Methods We use the NORDCAN database for the analyses: incidence data were available from 1943 in DK, 1953 in FI and NO and 1958 in SE, through 2016. Survival data were available from 1967 through 2016. World standard population was used in age standardization. Results The lowest incidence that we recorded for MPM was 0.02/100,000 for NO women and 0.05/100,000 for FI men in 1953–57, marking the incidence before the influence of asbestos. The highest rate of 1.9/100,000 was recorded for DK in 1997. Female incidence was much lower than male incidence. In each country, the male incidence trend for MPM culminated, first in SE around 1990. The regional incidence trends matched with earlier asbestos-related industrial activity, shipbuilding in FI and SE, cement manufacturing and shipbuilding in DK and seafaring in NO. Relative 1-year survival increased from about 20 to 50% but 5-year survival remained at or below 10%. Conclusion In the Nordic countries, the male incidence trends for MPM climaxed and started to decrease, indicating that the prevention of exposure was beneficial. Survival in MPM has improved for both sexes but long-term survival remains dismal.

Objective Patients with idiopathic pulmonary fibrosis (IPF) commonly present with sicca symptoms. This study aimed to assess labial minor salivary glands (LMSGs) in those patients to rule out Sjogren's syndrome (SS), in which sicca symptoms are the clinical hallmark. Study Design Cases of patients with IPF with sicca symptoms referred to the oral medicine clinic at the University of Florida within the last 13 years were selected with institutional review board approval. Demographic characteristics, clinical findings, laboratory results, and histomorphologic parameters were retrospectively analyzed. Results A total of 12 patients (9 men and 3 women, ages 55-76 years) were identified. History of exposure to asbestos or chemicals, smoking, and medication information was obtained. All patients reported sicca symptoms with 57% of those exhibiting objective or borderline dryness. Anti-SSA/Ro and anti-SSB/La were positive in 25% and 8% of the cases, respectively. Microscopically, 1 out of 12 patients was biopsy positive in the absence of anti-SSA/Ro, fulfilling the 2016 SS criteria with positive sialometry. Conclusions A LMSG biopsy is critical to identify SS in patients with diagnosed IPF and present sicca symptoms, especially those with negative serology, as revealed in our study.

Introduction:\ud Malignant pleural mesothelioma (MPM) is difficult to diagnose. An accurate blood biomarker could prompt specialist referral or be deployed in future screening. In earlier retrospective studies, SOMAscan proteomics (Somalogic, Boulder, CO) and fibulin-3 seemed highly accurate, but SOMAscan has not been validated prospectively and subsequent fibulin-3 data have been contradictory.\ud \ud Methods:\ud A multicenter prospective observational study was performed in 22 centers, generating a large intention-to-diagnose cohort. Blood sampling, processing, and diagnostic assessment were standardized, including a 1-year follow-up. Plasma fibulin-3 was measured using two enzyme-linked immunosorbent assays (CloudClone [used in previous studies] and BosterBio, Pleasanton, CA). Serum proteomics was measured using the SOMAscan assay. Diagnostic performance (sensitivity at 95% specificity, area under the curve [AUC]) was benchmarked against serum mesothelin (Mesomark, Fujirebio Diagnostics, Malvern, PA). Biomarkers were correlated against primary tumor volume, inflammatory markers, and asbestos exposure.\ud \ud Results:\ud A total of 638 patients with suspected pleural malignancy (SPM) and 110 asbestos-exposed controls (AECs) were recruited. SOMAscan reliably differentiated MPM from AECs (75% sensitivity, 88.2% specificity, validation cohort AUC 0.855) but was not useful in patients with differentiating non-MPM SPM. Fibulin-3 (by BosterBio after failed CloudClone validation) revealed 7.4% and 11.9% sensitivity at 95% specificity in MPM versus non-MPM SPM and AECs, respectively (associated AUCs 0.611 [0.557–0.664], p = 0.0015) and 0.516 [0.443–0.589], p = 0.671), both inferior to mesothelin. SOMAscan proteins correlated with inflammatory markers but not with asbestos exposure. Neither biomarker correlated with tumor volume.\ud \ud Conclusions:\ud SOMAscan may prove useful as a future screening test for MPM in asbestos-exposed persons. Neither fibulin-3 nor SOMAscan should be used for diagnosis or pathway stratification.

Background Substantial variation in health care costs for malignant pleural mesothelioma (MPM) has previously been identified. Materials and Methods We analyzed the changes in health care costs in MPM in Finland during 2002–2012. Finland has low‐threshold public health care and a mandatory Workers' Compensation scheme that covers all occupational‐related disease expenses. The costs include treatment costs for inpatients, hospice care, medication costs, rehabilitation costs, and travel costs. All costs are expressed in 2012 prices, adjusted using the consumer price index. Results A total of 907 MPM patients were included in the study. Mean duration of inpatient episodes increased 7% per year from 2002 to 2012, correlating with total costs (R2 = 0.861, p, Malignant pleural mesothelioma is a rare cancer, but one of the most frequent occupational malignant diseases. We evaluated the annual health care costs and changes in costs in Finland 2002–2012. Compared with the average health care costs, the total costs and the cost per patient were growing 2‐fold faster in mesothelioma patients. Only a proportion of healthcare costs were charged appropriately Workers' Compensation Insurance.

Despite Italy banning use and production of asbestos in 1992, it continues to represent a risk to human health due to its permanence in the places where it was located. The aim of this work is to estimate how many schools in Rome (Italy) have asbestos containing materials (ACM), and to assess whether the location, condition and nature of ACM can influence the level of risk for student health. 3,672 schools were contacted and 1,451 participated to asbestos survey. 692 bulk samples were collected and analyzed by optical and electron microscope and Fourier transform infrared spectrometer. About 16% of the surveyed schools had ACM. Most of the ACM were not accessible to students (water tanks, boiler thermal insulations). Asbestos-cement materials and vinyl floor tiles were the most common non-friable materials found in schools and equipment insulation linings and Bunsen burner gauze mats were the friable ACM found in science laboratories. Measures to prevent or reduce asbestos hazards were applied where necessary. This study allowed to develop the awareness of the asbestos health hazard among headteachers and the need to manage these hazards appropriately. It represents the beginning of a larger study leading to ACM national mapping in schools.

Mesothelioma Most mesotheliomas originate in the pleura and are due to asbestos exposure. The incidence is decreasing somewhat with asbestos remediation, but mortality remains high in part because ...

Background Neighborhood exposure to asbestos increases the risk of developing malignant mesothelioma (MM) in residents who live near asbestos mines and asbestos product plants. The area of Casale Monferrato (Northwest Italy) was impacted by several sources of asbestos environmental pollution, due to the presence of the largest Italian asbestos cement (AC) plant. In the present study, we examined the spatial variation of MM risk in an area with high levels of asbestos pollution and secondly, and we explored the pattern of clustering. Methods A population-based case–control study conducted between 2001 and 2006 included 200 cases and 348 controls. Demographic and occupational data along with residential information were recorded. Bivariate Kernel density estimation was used to map spatial variation in disease risk while an adjusted logistic model was applied to estimate the impact of residential distance from the AC plant. Kulldorf test and Cuzick Edward test were then performed. Results One hundred ninety-six cases and 322 controls were included in the analyses. The contour plot of the cases to controls ratio showed a well-defined peak of MM incidence near the AC factory, and the risk decreased monotonically in all directions when large bandwidths were used. However, considering narrower smoothing parameters, several peaks of increased risk were reported. A constant trend of decreasing OR with increasing distance was observed, with estimates of 10.9 (95% CI 5.32–22.38) and 10.48 (95%CI 4.54–24.2) for 0–5 km and 5–10 km, respectively (reference > 15 km). Finally, a significant (p Conclusions In this study, we found an increasing pattern of mesothelioma risk in the area around a big AC factory and we detected secondary clusters of cases due to local exposure points, possibly associated to the use of asbestos materials.

In the lungs, asbestos develops an Fe-rich coating (Asbestos Body, AB) that becomes the actual interface between the foreign fibers and the host organism. Conventional approaches to study ABs require an invasive sample preparation that can alter them. In this work, a novel combination of x-ray tomography and spectroscopy allowed studying unaltered lung tissue samples with chrysotile and crocidolite asbestos. The thickness and mass density maps of the ABs obtained by x-ray tomography were used to derive a truly quantitative elemental analysis from scanning x-ray fluorescence spectroscopy data. The average mass density of the ABs is compatible with that of highly loaded ferritin, or hemosiderin. The composition of all ABs analyzed was similar, with only minor differences in the relative elemental fractions. Silicon concentration decreased in the core-to-rim direction, indicating a possible partial dissolution of the inner fiber. The Fe content in the ABs was higher than that possibly contained in chrysotile and crocidolite. This finding opens two opposite scenarios, the first with Fe coming from the fiber bulk and concentrating on the surface as long as the fiber dissolves, the second where the Fe that takes part to the formation of the AB originates from the host organism Fe-pool.

Between 1948 and 1965, the Canari asbestos mine (Corsica, France) discharged 11 million tonnes of serpentinite rubble into the sea. This study, therefore, aims to assess the environmental and health risks associated with contamination of potentially toxic elements using bioindicators (seagrass and fish) in the areas bordering the former mine within the perimeter of the Cap Corse and Agriate Marine Natural Park. The results and multivariate statistical analyses of the potentially toxic elements, made it possible to identify a concentration gradient, a model of bioaccumulation, and the occurrence of different groups, thus reflecting a spatial variation of the contamination. These results indicate that the former asbestos mine can still be considered, 55 years after its closure, as a major source of Co, Cr, and Ni for marine ecosystems and still influences the quality of the coastal area today. Our study, therefore, indicates that the two most polluted sites (Albo and Negru) are the closest stations to the south of the old Canary asbestos mine. According to the Trace Elements Pollution Index (TEPI) values, 6 species were classified as having a high contamination level: Scorpaena notata (1.37), Scorpaena porcus (1.36), Sepia officinalis (1.27), Diplodus vulgaris (1.02), Spicara maena (0.95), and Mullus surmuletus (0.94). Regarding the potentially toxic elements measured in the edible tissues of fish, the concentrations were all below the regulatory thresholds and did not reveal any potential risk to human health (Cd, Cu, Fe, Pb, Se, Sn, Zn). This work provides new and useful information to improve the monitoring of the environmental quality of a region characterized by previous mining activity and to assess the potential risk to human health due to the consumption of fish. Beyond the purely scientific aspects, these results could serve as decision support at the regional level for the definition of long-term public policies.

Asbestos mining operations have left South Africa with a legacy of asbestos contamination and asbestos-related diseases continue to be a problem. The large-scale mining of three types of asbestos presents a unique opportunity to study malignant mesothelioma of the pleura (mesothelioma) in South Africa. This study aimed to describe the demographics of deceased individuals diagnosed with mesothelioma and explore any associations between the histological morphology of mesothelioma and asbestos characteristics. We reviewed the records of all deceased miners and ex-miners from the Pathology Automation System (PATHAUT) database of the National Institute of Occupational Health (NIOH) that were histologically diagnosed with mesothelioma in the period from January 2006–December 2016 (11 years). The study population does not include all cases of mesothelioma in South Africa but rather those that reached the compensation system. Crocidolite asbestos fibres were identified in the majority of mesothelioma cases (n = 140; 53.4%). The epithelioid subtype was most commonly present in both occupational and environmental cases. Cases with the sarcomatous subtype were older at death and fewer female cases were diagnosed with this subtype. No relationship between mesothelioma subtype and asbestos type or asbestos burden or fibre size was established.

Peer reviewed: True, Malignant mesothelioma is an aggressive tumour of the pleura (MPM) or peritoneum with a clinical presentation at an advanced stage of the disease. Current therapies only marginally improve survival and there is an urgent need to identify new treatments. Carcinoma-associated fibroblasts (CAFs) represent the main component of a vast stroma within MPM and play an important role in the tumour microenvironment. The influence of CAFs on cancer progression, aggressiveness and metastasis is well understood; however, the role of CAF-derived extracellular vesicles (CAF-EVs) in the promotion of tumour development and invasiveness is underexplored. We purified CAF-EVs from MPM-associated cells and healthy dermal human fibroblasts and examined their effect on cell proliferation and motility. The data show that exposure of healthy mesothelial cells to EVs derived from CAFs, but not from normal dermal human fibroblasts (NDHF) resulted in activating pro-oncogenic signalling pathways and increased proliferation and motility. Consistent with its role in suppressing Yes-Associated Protein (YAP) activation (which in MPM is a result of Hippo pathway inactivation), treatment with Simvastatin ameliorated the pro-oncogenic effects instigated by CAF-EVs by mechanisms involving both a reduction in EV number and changes in EV cargo. Collectively, these data determine the significance of CAF-derived EVs in mesothelioma development and progression and suggest new targets in cancer therapy.

Pleural mesothelioma (PM) is a rare and aggressive disease that arises from the mesothelial cells lining the pleural cavity. Approximately 80% of PM patients have a history of asbestos exposure. The long latency period of 20–40 years from the time of asbestos exposure to diagnosis, suggests that multiple somatic genetic alterations are required for the tumorigenesis of PM. The genomic landscape of PM has been characterized by inter- and intratumor heterogeneity associated with the impairment of tumor suppressor genes such as CDKN2A, NF2, and BAP1. Current systemic therapies have shown only limited efficacy, and none is approved for patients with relapsed PM. Advances in understanding of the molecular landscape of PM has facilitated several biomarker-driven clinical trials but so far, no predictive biomarkers for targeted therapies are in clinical use. Recent advances in the PM genetics have provided optimism for successful molecular strategies in the future. Here, we summarize the molecular mechanism underlying PM pathogenesis and review potential therapeutic targets.

The Asbestos Hazard Emergency Response Act (AHERA) became a law in 1986, and the US Environmental Protection Agency (USEPA) was mandated to promulgate rules to regulate the inspection, management, and abatement of asbestos-containing building materials (ACBM) in schools. This study describes 10 years (2008-2017) of AHERA compliance site inspection data conducted by the New Jersey Department of Health (NJDOH).To establish the level to which inspected NJ schools comply with AHERA regulations, to characterize compliance deficiencies including those that may lead to increased asbestos exposure risk to students and school employees, and to determine whether age, type, and geographic location of school impacted the likelihood of noncompliance.Information collected during 456 unique inspections between 2008 and 2017 was analyzed.Inspections were conducted at public and private schools in New Jersey. These included elementary, middle, and high schools, as well as charter and vocational/technical schools.Descriptive statistics and multiple logistic regression modeling of 3 factors, school type, geographical region, and school age.NJDOH inspectors found damage to friable ACBM in 50% (n = 229) of the schools and fiber release episodes in 27% of inspections (n = 121). The case of schools failing to attach warning labels on or immediately adjacent to ACBM was the most frequently noted compliance deficiency over the 10-year period. The modeling output showed that compliance was associated with the type of school and geographical region.Inspected schools during the 10-year period were in serious noncompliance with AHERA regulations. This included deficiencies that demonstrate a potential exposure to asbestos such as missing ACBM in management plans, damaged ACBM, lack of protection of short-term workers and custodial staff, and the identification of fiber release episodes. Modeling results of specific school characteristics can help direct limited resources to mitigate potential asbestos exposures.

Although alveolar macrophages play a critical role in malignant transformation of mesothelial cells following asbestos exposure, inflammatory and oxidative processes continue to occur in the mesothelial cells lining the pleura that may contribute to the carcinogenic process. Malignant transformation of mesothelial cells following asbestos exposure occurs over several decades; however, amelioration of DNA damage, inflammation, and cell injury may impede the carcinogenic process. We have shown in an in vitro model of asbestos-induced macrophage activation that synthetic secoisolariciresinol diglucoside (LGM2605), given preventively, reduced inflammatory cascades and oxidative/nitrosative cell damage. Therefore, it was hypothesized that LGM2605 could also be effective in reducing asbestos-induced activation and the damage of pleural mesothelial cells. LGM2605 treatment (50 µM) of huma n pleural mesothelial cells was initiated 4 h prior to exposure to asbestos (crocidolite, 20 µg/cm2). Supernatant and cells were evaluated at 0, 2, 4, and 8 h post asbestos exposure for reactive oxygen species (ROS) generation, DNA damage (oxidized guanine), inflammasome activation (caspase-1 activity) and associated pro-inflammatory cytokine release (IL-1β, IL-18, IL-6, TNFα, and HMGB1), and markers of oxidative stress (malondialdehyde (MDA) and 8-iso-prostaglandin F2a (8-iso-PGF2α). Asbestos induced a time-dependent ROS increase that was significantly (p < 0.0001) reduced (29.4%) by LGM2605 treatment. LGM2605 pretreatment also reduced levels of asbestos-induced DNA damage by 73.6% ± 1.0%. Although levels of inflammasome-activated cytokines, IL-1β and IL-18, reached 29.2 pg/mL ± 0.7 pg/mL and 43.9 pg/mL ± 0.8 pg/mL, respectively, LGM2605 treatment significantly (p < 0.0001) reduced cytokine levels comparable to baseline (non-asbestos exposed) values (3.8 pg/mL ± 0.2 pg/mL and 5.4 pg/mL ± 0.2 pg/mL, respectively). Furthermore, levels of IL-6 and TNFα in asbestos-exposed mesothelial cells were high (289.1 pg/mL ± 2.9 pg/mL and 511.3 pg/mL ± 10.2 pg/mL, respectively), while remaining undetectable with LGM2605 pretreatment. HMGB1 (a key inflammatory mediator and initiator of malignant transformation) release was reduced 75.3% ± 0.4% by LGM2605. Levels of MDA and 8-iso-PGF2α, markers of oxidative cell injury, were significantly (p < 0.001) reduced by 80.5% ± 0.1% and 76.6% ± 0.3%, respectively. LGM2605, given preventively, reduced ROS generation, DNA damage, and inflammasome-activated cytokine release and key inflammatory mediators implicated in asbestos-induced malignant transformation of normal mesothelial cells.

Background There is conflicting evidence on the association between asbestos exposure and prostate cancer (PCa). Two recent meta-analyses have claimed that exposure is associated with increased PCa incidence and mortality, but they suffer from some methodological flaws. Given the potential importance of this research question, we aimed to perform a methodologically sound systematic review and meta-analysis to investigate the association between occupational asbestos exposure and the incidence of and mortality from PCa. Methods We followed PRISMA guidelines to systematically search for pertinent articles in three relevant electronic databases: Pubmed, Scopus, and Embase, from their inception to July 2020. The methodological quality of included articles was evaluated using the US National Institutes of Health tool. Standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) for PCa, as well as respective 95% confidence intervals (CIs), were extracted or calculated for each included cohort. Main and subgroup meta-analyses according to first year of employment, industry, asbestos type, and geographic region were performed. Results Sixty-five articles comprising 68 cohorts were included. PCa incidence and mortality were not significantly associated with occupational asbestos exposure (pooled SIR: 1.06, 95% CI: 1.00-1.13, P = 0.062; pooled SMR: 1.03, 95% CI: 0.99-1.06, P = 0.115). PCa incidence was higher among workers employed after 1960 (SIR: 1.10, 95% CI: 1.01-1.20). Pooled SIR was elevated in European (SIR: 1.09, 95% CI: 1.01-1.18) and UK cohorts (SIR: 1.05, 95% CI: 1.02-1.09). Mortality was elevated in North American cohorts (SMR: 1.06, 95% CI: 1.02-1.10). Studies of lower methodological quality appeared to yield elevated SIRs or SMRs. Conclusions This systematic review and meta-analysis provides evidence that men with occupational asbestos exposure have a PCa incidence and mortality similar to that of the general population. Temporal and geographical variables seem to be related to higher SMR or SIR.

Background Mesothelioma of the pleural or peritoneal cavities is one of the deadliest cancer types. The incidence of pleural subtypes has decreased over time due to decrease in asbestos exposure, and the current treatment landscape is changing due to introduction of novel therapies. In this study we have analysed contemporary epidemiological data of mesothelioma on a national level before the advent of immunotherapy. Material and methods Complete national data on 1509 pleural and peritoneal malignant mesothelioma from the Cancer Registry of Norway from 2000 to 2019 are presented. Age standardised incidence and median survival were calculated. Results The age-standardised incidence of pleural mesothelioma among males has decreased from 1.7 per 100 000 in 2000-2004 to 1.1 in 2015-2019, whereas the incidence for females has been stable, lower than 0.3 per 100 000 throughout the period. Incidence of peritoneal mesotheliomas remained low, below 0.08 per 100 000. The female to male ratio among pleural mesotheliomas was 1:7 with no differences among morphological subtypes, whereas this ratio was 1:1.2 in peritoneal mesotheliomas. Median age at diagnosis for pleural mesothelioma was 73 years and 76 years for females and males respectively in the last 5-year period, and 67 years for peritoneal mesotheliomas of both sexes. Median survival among pleural mesotheliomas has been stable, with significantly worse prognosis among sarcomatoid subtype (5.4 months) compared to epithelioid subtype (15.8 months). Peritoneal mesothelioma of the epithelioid subtype, representing 38% of cases, had a median survival of 43.3 months, contrasting the non-epithelioid subtype of 5.1 months. Discussion Mesothelioma is still a significant disease with a dismal prognosis. Improvement in treatment is warranted.

From 2018 to 2020, the United States Environmental Protection Agency (EPA) performed a risk evaluation of chrysotile asbestos to evaluate the hazards of asbestos-containing products (e.g. encapsulated products), including brakes and gaskets, allegedly currently sold in the United States. During the public review period, the EPA received more than 100 letters commenting on the proposed risk evaluation. The Science Advisory Committee on Chemicals (SACC), which peer reviewed the document, asked approximately 100 questions of the EPA that they expected to be addressed prior to publication of the final version of the risk assessment on 30 December 2020. After careful analysis, the authors of this manuscript found many significant scientific shortcomings in both the EPA's draft and final versions of the chrysotile risk evaluation. First, the EPA provided insufficient evidence regarding the current number of chrysotile-containing brakes and gaskets being sold in the United States, which influences the need for regulatory oversight. Second, the Agency did not give adequate consideration to the more than 200 air samples detailed in the published literature of auto mechanics who changed brakes in the 1970-1989 era. Third, the Agency did not consider more than 15 epidemiology studies indicating that exposures to encapsulated chrysotile asbestos in brakes and gaskets, which were generally in commerce from approximately 1950-1985, did not increase the incidence of any asbestos-related disease. Fourth, the concern about chrysotile asbestos being a mesothelioma hazard was based on populations in two facilities where mixed exposure to chrysotile and commercial amphibole asbestos (amosite and crocidolite) occurred. All 8 cases of pleural cancer and mesothelioma in the examined populations arose in facilities where amphiboles were present. It was therefore inappropriate to rely on these cohorts to predict the health risks of exposure to short fiber chrysotile, especially of those fibers filled with phenolic resins. Fifth, the suggested inhalation unit risk (IUR) for chrysotile asbestos was far too high since it was not markedly different than for amosite, despite the fact that the amphiboles are a far more potent carcinogen. Sixth, the approach to low dose modeling was not the most appropriate one in several respects, but, without question, it should have accounted for the background rate of mesothelioma in the general population. Just one month after this assessment was published, the National Academies of Science notified the EPA that the Agency's systematic review process was flawed. The result of the EPA's chrysotile asbestos risk evaluation is that society can expect dozens of years of scientifically unwarranted litigation. Due to an aging population and because some fraction of the population is naturally predisposed to mesothelioma given the presence of various genetic mutations in DNA repair mechanisms (e.g. BAP1 and others), the vast majority of mesotheliomas in the post-2035 era are expected to be spontaneous and unrelated in any way to exposure to asbestos. Due to the EPA's analysis, it is our belief that those who handled brakes and gaskets in the post-1985 era may now believe that those exposures were the cause of their mesothelioma, when a risk assessment based on the scientific weight of evidence would indicate otherwise.

Funder: British Lung Foundation (BLF); doi: https://doi.org/10.13039/501100000351, Funder: Royal Society through a University Research Fellowship and the Engineering and Physical Sciences Research Council (EPRSC), Funder: China Scholarship Council (CSC); doi: https://doi.org/10.13039/501100004543, Mesothelioma is an aggressive cancer that is associated with exposure to asbestos. Although asbestos is banned in several countries, including the UK, an epidemic of mesothelioma is predicted to affect middle-income countries during this century owing to their heavy consumption of asbestos. The prognosis for patients with mesothelioma is poor, reflecting a failure of conventional chemotherapy that has ultimately resulted from an inadequate understanding of its biology. However, recent work has revolutionised the study of mesothelioma, identifying genetic and pathophysiological vulnerabilities, including the loss of tumour suppressors, epigenetic dysregulation and susceptibility to nutrient stress. We discuss how this knowledge, combined with advances in immunotherapy, is enabling the development of novel targeted therapies.

Malignant pleural mesothelioma (MPM) is an incurable malignancy associated with high symptom burden and poor prognosis. The relationship between asbestos exposure and MPM incidence is well-established. The incidence rate of MPM in Australia and New Zealand is among the highest globally. Matching the experience of other nations with legal restrictions on asbestos, incidence is expected to fall. In contrast, the incidence of MPM is rising in the developing nations of the Asia-Pacific as consumption and mining (albeit to a lesser extent) of asbestos continues. The incidence of MPM in these nations is currently low or unknown, reflecting insufficient latency periods since industrial use of asbestos, deficient resources for accurate diagnosis, and lack of occupational disease or cancer registries. The landscape of treatment for MPM is rapidly changing with combination immunotherapy now demonstrating improved survival in the first-line setting. Considering vast global inequity in access to anticancer treatments, establishing minimum standard of care for MPM in developing nations is of greater significance. Here, we review the evidence that form the basis of our minimum-standard recommendations for diagnosis, systemic treatment, management of recurrent pleural effusions, and symptom management. We also briefly review evidence-based treatment that may be considered for those with access.

Background Malignant pleural mesothelioma is a highly aggressive tumor associated with asbestos exposure. There are few effective treatment options for mesothelioma, and patients have a very poor prognosis. Mesothelioma has the potential to represent an appropriate disease to prevent because of its strong association with asbestos exposure and the long latency from exposure to the disease on-set. Methods In the present study, we tested biological activity and toxicity of an artichoke freeze-dried extract (AWPC) as potential complementary preventive/early stage treatment agent for mesothelioma. This phase II clinical study then was conducted in 18 male-patients with evidence of radiographic characteristics related to asbestos exposure such as asbestosis or benign pleural disease as surrogate disease for mesothelioma clinical model. Results We investigate AWPC biological activity assessing its effect on mesothelin serum level, a glycoprotein with low expression in normal mesothelial cells and high expression in mesothelioma and asbestos related diseases. We also assess the AWPC effect on circulating miRNAs, as novel biomarkers of both cancer risk and response to therapeutic targets. While we found a small and not significant effect of AWPC on mesothelin serum levels, we observed that AWPC intake modulated 11 serum miRNAs related to gene-pathways connected to mesothelioma etiology and development. In terms of toxicity, we also did not observe any severe adverse effects associated to AWPC treatment, only gastro-intestinal symptoms were reported by five study participants. Conclusions We observed an interesting AWPC effect on miRNAs which targets modulate mesothelioma development. New and much larger clinical studies based on follow-up of workers exposed to asbestos are needed to corroborate the role of AWPC in prevention and early treatment of mesothelioma. Trial registration ClinicalTrials.gov, NCT02076672. Registered 03/03/2014.

International audience; Malignant pleural mesothelioma (MPM) is an aggressive cancer mainly related to asbestos exposure. Despite recent therapeutic advances, notably immunotherapies, the benefit remains limited and restricted to a small percentage of patients. Thus, a better understanding of the disease is needed to identify new therapeutic strategies. Recently, interleukin 7 receptor (IL-7R) has been described as being expressed by MPM cells and associated with poorer patient survival. Thus, the aim of this work was to study the IL-7R/IL-7 pathway in MPM using patient samples. We found that, although more than 40% of MPM cells expressed IL-7R, IL-7 had no effect on their intracellular signaling. Accordingly, the addition of IL-7 to the culture medium did not affect MPM cell growth. Using The Cancer Genome Atlas (TCGA) database, we showed that high IL7 gene expression in MPM tumors was associated with a higher overall patient survival and an induction of genes involved in the immune response. In pleural effusions (PEs), we found that IL-7 concentration was not a good diagnostic biomarker. However, we observed that high IL-7 levels in PEs were associated with shorter survival of MPM patients, but not of lung cancer patients. The prognostic value of IL-7 was also conserved when only patients with epithelioid mesothelioma, the most common histological type of MPM, were analyzed. Taken together, our study suggests that, although the IL-7R/IL-7 signaling pathway is not functional in MPM cells, IL-7 expression in PEs may have prognostic value in MPM patients.

In Calabria (Southern Italy) naturally occurring asbestos (NOA) mainly occurs in the ophiolitic sequences cropping in the Mount Reventino area. The most common type of asbestos detected was the amphibole tremolite; fibrous antigorite and minor chrysotile were also found. The development of asbestos-related diseases depends on, among other things, the morphological characteristics of fibers, length and width, affecting the durability of asbestos fibers in the lung. In this work fifteen lung samples of sheep, goats and wild boars, grazing around the Mount Reventino area were collected and asbestos fibers analysed. Observed fibers (357), of which 97 % were tremolite and 3 % antigorite fibers, were grouped according to species, grazing area and age of the animals. The aim of this work was to highlight any differences among the groupings and to compare our size results with data in literature related to exposed populations. Principal Component Analysis (PCA) highlighted a positive correlation between tremolite fiber length and width and revealed groupings in terms of animal age. The Kruskal-Wallis test showed statistically significant differences between fiber mean widths in young and old animals. 63 % observed asbestiform fibers were longer than 5 μm and 7 % of the fibers were longer than 20 μm (critical fiber length connected to the frustrated phagocytosis by the macrophage). Fibers conforming to the Stanton Hypothesis size (predictor of the carcinogenic potency of fibers) were 1 %. Our size parameters of fibers detected in the animal lungs were in fairly good agreement with literature data for human asbestos exposure to tremolite. These results confirmed that an animal-sentinel system could be used to monitor the natural background of the airborne breathable fibers exposure. In addition, the size correlation of animal-human breathed fibers could be useful to study their potential toxicity. Additional data are necessary for improving the agreement with human exposure data.

Esophageal cancer is the sixth most common cause of cancer death worldwide. In France, Brittany is one of the regions most seriously affected. This increased incidence is usually linked to high rates of alcohol overconsumption and smoking, established risk factors for esophageal cancer, but the region has special occupational exposures. We aim to describe the occupational exposures of patients with esophageal cancer. Between June and October 2020, we conducted a monocentric descriptive study in a French Teaching Hospital and identified 37 eligible patients. We gathered data through a systematic individual interview for each participant and by an analysis of their medical file. We were able to include 36 patients; most were men (n = 27, 75.0%) and smokers (n = 25, 69.4%), 21 (58.3%) presented an adenocarcinoma esophageal cancer, 13 (36.1%) a squamous cell cancer, and 2 other types. On occupational exposure, patients declared respectively high exposure by manipulating asbestos materials for 11 (30.6%) patients, regularly in contact with benzene by handling fuel in 7 cases (19.4%), chlorinated solvents in 4 cases (11.1%), pesticides in 4 cases, and ionizing radiation exposure in 3 patients (8.3%). Our findings support the creation of a large-scale study to explore the impact of occupational exposures, particularly exposure to asbestos and hydrocarbons.