Occupational Asbestos Exposure Research Articles

Health surveillance for former asbestos exposed worker: a specific programme developed in an Italian region.

Asbestos-related diseases usually have a long latency since first exposure and this legitimates a health surveillance programme addressed to asbestos workers after the cessation of their occupational exposure. After a brief history of health surveillance initiatives performed in Italy as well as in other countries, we describe a regional programme for former asbestos-exposed workers, focusing on organizational features. A regional group of experts defined its operational and economical aspects. The Regional Council supported the whole programme, making it free of charge for all subjects who fulfil the predefined enrolment criteria (being resident in the region, being younger than 80 years old with cessation of occupational asbestos exposure within the last 30 years). The programme activities are classified in two levels: a first level for a basic health evaluation and a second level for in-depth analyses. In order to guarantee an homogeneous delivery in the whole region, the programme has to be performed by public health services with a quality control of activities. The involvement of specific public health services and the cooperation of social stakeholders are expected to play a major role in overcoming still open critical issues, such as the lack of programme existence awareness and adhesion, the correct stratification of subjects for the follow-up, and the real homogeneous delivery of the health surveillance in whole region.

Differences between peritoneal and pleural mesothelioma in Lombardy, Italy

BackgroundWe examined characteristics of peritoneal (PEM) and pleural (PLM) mesothelioma in Lombardy, Italy. MethodsFrom the Lombardy Mesothelioma Registry we selected PEM (N=300) and PLM (N=5011) cases diagnosed in 2000–2014. We investigated asbestos exposure and presence of asbestosis or pleural plaques. ResultsIncidence rates (per 1,000,000 person-years, world standardized) of PEM were 1.2 (men) and 0.9 (women), compared with 22.6 and 8.4 for PLM.Asbestosis (both genders) and pleural plaques (men) were more frequent among PEM cases. Occupational asbestos exposure was similar in PEM and PLM cases. We found higher proportions of PEMs employed in the asbestos cement production. ConclusionThe higher frequency of pleural plaques in PEM cases confirm the association between asbestos and peritoneal mesothelioma. The higher proportions of asbestosis and of past employment in the asbestos-cement sector among PEM cases suggest a possible role of high exposures to asbestos in the peritoneal mesothelioma genesis.

Mesothelioma

Malignant mesotheliomas are rare and aggressive tumours arising from mesothelial cells of the pleura and peritoneum. Infrequent sites of origin are the pericardium and tunica vaginalis testis. More than 80% of mesotheliomas are localized in the pleura. Men are more frequently affected than women. The median age is >60years. Asbestos exposure is the best known aetilogical risk factor and is reported in 54-90% of patients. In Germany, malignant mesotheliomas caused by occupational asbestos exposure are compensated as occupational disease since 1977. Several neoplastic and non-neoplastic lesions like metastasis, sarcomas, lymphomas or pleuritis with reactive mesothelial proliferation have to be distinguished from malignant mesotheliomas. Especially, the pathohistological differentiation between atypical reactive mesothelial proliferation from malignant mesothelioma is a diagnostic challenge.

Peritoneal Mesothelioma: A Challenge to Medical Profession

Malignant peritoneal mesothelioma (MPM) is an extremely rare cancer of peritoneum. It is associated with very poor prognosis due to late presentation and non-specific symptoms. We present a case of primary peritoneal mesothelioma in a 54 year old Hispanic female. She presented with epigastric abdominal pain and bloating for 5 months in the background of chronic non-specific abdominal discomfort. She had no history of occupational asbestos exposure, family history of cancer, smoking or weight loss. Her hemoglobin and chemistry were normal. Initial abdominal CT showed non-specific changes including loculated intra-abdominal ascites and mild epiphrenic adenopathy. Patient was referred for diagnostic laparoscopy. However, surgeons did not proceed with a surgical intervention initially. Her upper endoscopy and cystoscopy were performed and were normal. Her prior colonoscopy was normal. Repeat abdominal CT scan 3 month later revealed moderate volume of abdominal and pelvic ascites, worsening epiphrenic adenopathy, and mildly thickened anterior urinary bladder wall. Diagnostic laparoscopy was performed. Numerous implants were found on serosal surface of internal organs, peritoneum and omentum. Pathology specimen was consistent with malignant mesothelioma-Epithelioid type. Patient underwent debulking surgery, including resection and reconstructions of right hemi-diaphragm, cholecystectomy, right colectomy, partial gastrectomy, distal pancreatectomy, splenectomy, transverse colectomy, with temporary loop ileostomy followed by hyperthermic intraperitoneal chemotherapy (HIPEC) and cisplatin therapy for 6 months. Patient is disease free at 3 years postoperatively, and she is doing well with close follow-up. Malignant peritoneal mesothelioma is very difficult to diagnose due to nonspecific clinical presentation and clinical course. Diagnosis requires high level of clinical suspicion. Diagnosis is based on good quality imaging, pathology and immunohistochemistry. MPM can be treated with debulking surgery and intra-peritoneal chemotherapy or radiotherapy.

Cancer of the esophagus and asbestos exposure.

Our study aimed at analyzing incidence and mortality from esophageal cancer within a cohort of workers with previous occupational asbestos exposure (ARDCo Program). A 10-year follow-up study was conducted in the 14 515 male subjects included in this program between October 2003 and December 2005. Follow-up began when exposure stopped. Asbestos exposure was analyzed by industrial hygienists using data from a standardized questionnaire. The Cox model was used, with age as the time axis variable adjusted for smoking, time since first exposure (TSFE) and cumulative exposure index (CEI) of exposure to asbestos. We reported a significant dose-response relationship between CEI of exposure to asbestos and esophageal cancer, in both incidence (hazard ratio [HR] 1.26, 95% confidence interval [CI] 1.00-1.58), and mortality (HR 1.40, [95%CI 1.12-1.75]). This large-scale study suggests the existence of a relationship between asbestos exposure and cancer of the esophagus.

Ambient Asbestos Fiber Concentrations and Long-Term Trends in Pleural Mesothelioma Incidence between Urban and Rural Areas in the United States (1973-2012).

Over the past 40 years, measured ambient asbestos concentrations in the United States have been higher in urban versus rural areas. The purpose of this study was to determine whether variations in ambient asbestos concentrations have influenced pleural mesothelioma risk in females (who generally lacked historic occupational asbestos exposure relative to males). Male pleural mesothelioma incidence trends were analyzed to provide perspective for female trends. Annual age-adjusted incidence rates from 1973 to 2012 were obtained from the SEER 9, 13, and 18 databases for urban and rural locations, and standardized rate ratios were calculated. Female rural rates exceeded urban rates in almost half of the years analyzed, although the increases were not statistically significant, which is in line with expectations if there was no observable increased risk for urban locations. In contrast, male urban rates were elevated over rural rates for nearly all years examined and were statistically significantly elevated for 22 of the 40 years. Trend analyses demonstrated that trends for females remained relatively constant over time, whereas male urban and rural incidence increased into the 1980s and 1990s, followed by a decrease/leveling off. Annual female urban and rural incidence rates remained approximately five- to six-fold lower than male urban and rural incidence rates on average, consistent with the comparatively increased historical occupational asbestos exposure for males. The results suggest that differences in ambient asbestos concentrations, which have been reported to be 10-fold or greater across regions in the United States, have not influenced the risk of pleural mesothelioma.

A 30-year mortality and respiratory morbidity study of refractory ceramic fiber workers

Aim: Report mortality (n = 1119), cancer incidence (n = 1207) and radiographic (n = 1451) findings from a 30-year investigation of current and former refractory ceramic fiber (RCF) workers.Methods: Cause of death, health and work histories, radiographs and spirometry were collected. Mortality and cancer incidence were analyzed. Logistic regression analysis investigated the associations of latency and cumulative fiber exposure (CFE) on radiographic changes.Results: The mortality study showed no increase in standardized mortality rates (SMR) for lung cancer, but urinary cancers were significantly elevated in the higher exposed group (SMR = 3.62, 95% CI: 1.33–7.88) and leukemia in the total cohort (SMR = 2.51, 95% CI: 1.08–4.94). One death attributed to mesothelioma was identified (SMR = 2.86, 95% CI: 0.07–15.93) in a worker reporting some asbestos exposure. The overall rate of pleural changes was 6.1%, attaining 21.4% in the highest CFE category for all subjects (adjusted odds ratio (aOR) = 6.9, 95% CI: 3.6–13.4), and 13.0% for those with no reported asbestos exposure (OR= 9.1, 95% CI: 2.5–33.6). Prevalence for recent hires (≥1985) was similar to the background. Interstitial changes were not elevated. Localized pleural thickening was associated with small decreases in spirometry results.Conclusion: Increases in leukemia and urinary cancer but not lung cancer mortality were found. One death attributed to mesothelioma was observed in a worker with self-reported asbestos exposure and a work history where occupational asbestos exposure may have occurred, rendering uncertainties in assigning causation. Radiographic analyses indicated RCF exposure alone is associated with increased pleural but not interstitial changes. Reductions in RCF exposure should continue. The mortality study is ongoing.

The economic burden of lung cancer and mesothelioma due to occupational and para-occupational asbestos exposure

ObjectivesTo estimate the economic burden of lung cancer and mesothelioma due to occupational and para-occupational asbestos exposure in Canada.MethodsWe estimate the lifetime cost of newly diagnosed lung cancer and mesothelioma...

Environmental asbestos exposure and risk of mesothelioma.

Mesothelioma is commonly considered an occupational disease occurring as a result of asbestos exposure in the workplace. Several avenues for environmental asbestos exposures have been described and may be associated with asbestos related disease, including mesothelioma. Worker take-home asbestos, or para-occupational exposure, has been well documented and is the most commonly reported pathway for asbestos exposure among mesothelioma cases that do not have history of occupational asbestos exposure. Observational studies have evaluated several communities with elevated mesothelioma incidence and environmental exposures attributed to local asbestos-related industries. Potential, but uncertain, mesothelioma risk also may be associated with general population asbestos exposure through contact with asbestos-containing commercial products, particularly housing materials that can be easily disturbed through normal activity. Finally, studies have described elevated mesothelioma incidence in several areas where populations are exposed to naturally occurring asbestos materials. These various environmental asbestos exposure pathways are poorly understood, and further studies should be pursued to evaluate their respective importance for population mesothelioma risk.

Dose-time-response association between occupational asbestos exposure and pleural mesothelioma

ObjectivesEarly occupational exposure to asbestos has been shown to be associated with an increased risk of pleural mesothelioma (PM), which suggests that the timing of exposure might play a role...

Pleural mesothelioma in doll manufacture: possible asbestos exposure.

The occurrence of malignant mesothelioma is almost always causally associated to asbestos exposure but, considering women occurrences, this association is often difficult to demonstrate and consequently the asbestos exposure is defined as 'unknown'. To describe the working activity and to give occupational asbestos exposure probability estimation related to an uncommon and poorly investigated productive sector: doll manufacture. From the Province of Brescia Mesothelioma Registry, established in 1993 on population-based criteria, we have extracted the certified mesothelioma diagnosis cases, related to patients who were employed for some time in doll manufacture. Among the 757 total cases of malignant mesothelioma registered and studied up to 2016, we found 3 cases of pleural epithelial mesothelioma histologically diagnosed in young women who had worked in two doll manufacturing companies and whose asbestos exposure had been initially defined as 'unknown', because an environmental, family or extra-professional asbestos exposure was considered unlikely. However, the judicial autopsy performed on one of the 3 women had allowed examining lung tissue samples with Scanning Electron Microscopy. This technique showed a concentration of amphiboles fibers of about 12,000,000 per gram of dry lung tissue, with a consequent re-classification of asbestos exposure from 'unknown' to 'occupational certified'. Mesotheliomas in women with no apparent occupational asbestos exposure are normally referred to life or family environmental exposure. Moreover, it is known that occupational asbestos exposure in women is difficult to recognize. Previously, only one publication had reported two cases of mesothelioma in cloth doll manufacture. The occurrence of two mesothelioma cases in the same company out of the three here presented was suggesting an occupational exposure. The finding of a high amphibole fibers lung concentration confirmed the previous hypothesis, despite the impossibility to determine the circumstances with good evidence. The three cases of mesothelioma in doll production workers suggest that also in this restricted manufacturing sector had occurred an occupational asbestos exposure, which is up to now unknown and isn't due only to the use of sewing or ironing machines. The lung asbestos fibers burden analysis is confirmed to be a decisive factor in the assessment of mesothelioma cases with 'unknown' exposure.

Pleural mesothelioma in household members of asbestos-exposed workers in Friuli Venezia Giulia, Italy.

Malignant mesothelioma is closely associated to asbestos exposure. One such exposure may occur through contact with occupationally exposed household members and their belongings. This study examines the features of pleural mesothelioma attributable only to asbestos brought home by another family member. The data sources were 1063 mesothelioma cases diagnosed between 1995 and 2014, from the Friuli Venezia Giulia Mesothelioma Register. In all cases the diagnosis of mesothelioma was based on the pathology report. Exposure information and demographic data were acquired by an occupational medical standardized questionnaire/interview. Household-exposure mesothelioma cases included 33 women and 2 men. Relationships were: wives (N = 22), daughters (N = 9), sons (N = 2), and mothers (N = 2). Asbestos exposure in the workers predominantly occurred in shipyards. Out of the 35 pleural cases, 19 were epithelial, 9 biphasic, 3 sarcomatoid, and 4 not specified. The mean age at diagnosis was 77 years old. The mean latency was 59 years, with wives having a significant shorter latency than offspring. Latency was not significantly related to morphology and asbestosis. The overall mean survival was 16 months (median 11 months) but treatment was beneficial (mean 16 months vs. 7 months). Biphasic/sarcomatoid histology and presence of asbestosis were associated with a decreased survival, although not with statistical significance. Our data confirms that household exposure increases the risk for pleural mesothelioma amongst women with no history of occupational asbestos exposure. This is an ongoing problem in many countries, as well as in Italy, where the evaluation of a framework for the compensation of these cases is under debate. Int J Occup Med Environ Health 2017;30(3):419-431.

Exposure-Response Analyses of Asbestos and Lung Cancer Subtypes in a Pooled Analysis of Case-Control Studies.

Evidence is limited regarding risk and the shape of the exposure-response curve at low asbestos exposure levels. We estimated the exposure-response for occupational asbestos exposure and assessed the joint effect of asbestos exposure and smoking by sex and lung cancer subtype in general population studies. We pooled 14 case-control studies conducted in 1985-2010 in Europe and Canada, including 17,705 lung cancer cases and 21,813 controls with detailed information on tobacco habits and lifetime occupations. We developed a quantitative job-exposure-matrix to estimate job-, time period-, and region-specific exposure levels. Fiber-years (ff/ml-years) were calculated for each subject by linking the matrix with individual occupational histories. We fit unconditional logistic regression models to estimate odds ratios (ORs), 95% confidence intervals (CIs), and trends. The fully adjusted OR for ever-exposure to asbestos was 1.24 (95% CI, 1.18, 1.31) in men and 1.12 (95% CI, 0.95, 1.31) in women. In men, increasing lung cancer risk was observed with increasing exposure in all smoking categories and for all three major lung cancer subtypes. In women, lung cancer risk for all subtypes was increased in current smokers (ORs ~two-fold). The joint effect of asbestos exposure and smoking did not deviate from multiplicativity among men, and was more than additive among women. Our results in men showed an excess risk of lung cancer and its subtypes at low cumulative exposure levels, with a steeper exposure-response slope in this exposure range than at higher, previously studied levels. (See video abstract at, http://links.lww.com/EDE/B161.).

Pleural plaques: markers of asbestos exposure or independent risk factor for pleural mesothelioma? A case report of mesothelioma developed on a pleural plaque in a worker with occupational asbestos exposure

Pleural plaques: markers of asbestos exposure or independent risk factor for pleural mesothelioma? A case report of mesothelioma developed on a pleural plaque in a worker with occupational asbestos exposure

MA03.06 Cost Effectiveness of Chest Scan Screeing for Lung Cancer in Abestos Occupational Exposure Subjects: A Model Based Study

The National Lung Screening trial (NLST) showed that screening with low-dose computed tomography (CT) compared with chest radiography reduced lung-cancer mortality. There is very few data's on subjects with occupational asbestos exposure. We examined the cost-effectiveness of CT lung cancer screening in a French cohort of asbestos post professional exposure subjects (APEXS cohort). We estimated mean lif-years, costs and incremental cost-effectiveness ration (ICER) for screening with low-dose CT compare to no screening in this population of asbestos exposed subjects. Estimations of life-years gained were based on the efficacy of NLST trial applied to APEXS cohort, adjusted to sex and age. Costs were limited to direct costs, from the payer perspective. We also performed sensitivity analysis based on several assumptions of screening program efficacy. Compared with no screening, screening with low-dose CT, over a period of 2 years, will cost, for 1000 subjects of APEXS cohort 312 645 €, will provide 9.4 additional life-years. The corresponding ICER was 33 102 € per life-gained. Sensitivity analysis showed that this result is sensitive to screening program efficacy (number, stage, and survival diagnosed by the program). ICER of low-dose CT lung cancer program in a cohort of asbestos post occupational exposure population appears as acceptable from the French health system.

Glycoprotein YKL-40 Levels in Plasma Are Associated with Fibrotic Changes on HRCT in Asbestos-Exposed Subjects.

YKL-40 is a chitinase-like glycoprotein produced by alternatively activated macrophages that are associated with wound healing and fibrosis. Asbestosis is a chronic asbestos-induced lung disease, in which injury of epithelial cells and activation of alveolar macrophages lead to enhanced collagen production and fibrosis. We studied if YKL-40 is related to inflammation, fibrosis, and/or lung function in subjects exposed to asbestosis. Venous blood samples were collected from 85 men with moderate or heavy occupational asbestos exposure and from 28 healthy, age-matched controls. Levels of plasma YKL-40, CRP, IL-6, adipsin, and MMP-9 were measured with enzyme-linked immunosorbent assay (ELISA). Plasma YKL-40 levels were significantly higher in subjects with asbestosis (n = 19) than in those with no fibrotic findings in HRCT following asbestos exposure (n = 66) or in unexposed healthy controls. In asbestos-exposed subjects, plasma YKL-40 correlated negatively with lung function capacity parameters FVC (Pearson's r −0.259, p = 0.018) and FEV1 (Pearson's r −0.240, p = 0.028) and positively with CRP (Spearman's rho 0.371, p < 0.001), IL-6 (Spearman's rho 0.314, p = 0.003), adipsin (Spearman's rho 0.459, p < 0.001), and MMP-9 (Spearman's rho 0.243, p = 0.025). The present finding suggests YKL-40 as a biomarker associated with fibrosis and inflammation in asbestos-exposed subjects.

Residual fibre lung burden among patients with pleural mesothelioma who have been occupationally exposed to asbestos

ObjectivesTo evaluate the lungs asbestos fibres concentration in participants with malignant pleural mesothelioma (MPM) who have been occupationally exposed.MethodsThe lung samples were obtained from pleuropneumonectomies or autopsies of 271 male...

Elemental and immunohistochemical analysis of the lungs and hilar lymph node in a patient with asbestos exposure, a pilot study.

Studies have shown that inhaled mine dust, such as asbestos, can be translocated to various organs including the lymph nodes. Recently, we have established a protocol that enables us to identify inhaled elements using paraffin embedded lung specimens by in-air microparticle-induced X-ray emission (micro-PIXE). However, little research has examined the concentration of these inhaled fibers in various organs or the mechanisms of their translocation. In this study, we compared the concentration of inhaled fibers in the lung parenchyma to the concentration in the hilar lymph node as well as to determine the elemental spatial distribution of the inhaled fibers in a patient with occupational asbestos exposure. Lung tissues and hilar lymph node in a patient with asbestos exposure were used in this study. Elemental analysis was performed by in-air micro-PIXE. Immunohistochemical analysis was performed using anti CD163, smooth muscle actin, vimentin and β-catenin antibody. The analysis revealed that the amount of inhaled silicon was approximately 6 times higher in the lymph node than in the lungs. The spatial analysis showed that silicon, iron and aluminium were co-localized in the hilar lymph node. The immunohistochemical analysis showed localized agreement of the inhaled fibers with macrophages, smooth muscle actin, and vimentin in the hilar lymph node. This study showed that in-air micro-PIXE could be useful for analyzing the elemental distribution and quantification of inhaled fibers in the human body. Furthermore, immunohistochemistry in combination with in-air micro-PIXE analyses may help to determine the mechanism of mine dust distribution in vivo.

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

BackgroundThe 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.MethodsThree 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 (9th edition) and the Korean Standard Classification of Occupations code (6th 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.ResultsBased 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.ConclusionThe 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.

Malignant mesothelioma in Australia 2015: Current incidence and asbestos exposure trends

ABSTRACTAustralia is known to have had the highest per-capita asbestos consumption level of any nation, reaching a peak in the 1970s. Although crocidolite was effectively banned in the late 1960s, and amosite use ceased in the mid 1980s, a complete asbestos ban was not implemented until 2003. This resulted in an epidemic of asbestos-related disease, which has only now reached its peak. Between 1982 and 2011, 13,036 individuals were newly diagnosed with malignant mesothelioma, with 690 diagnosed in 2011. A further 778 cases were identified between 1945 and 1981 from retrospective searches and the first 2 years of the Australian Mesothelioma Program. The age-standardized malignant mesothelioma incidence rate has leveled off in the last 10 years (2.8 per 100,000 in 2011). There has been a marked increase over time in the age-specific incidence rates for individuals aged 75 years or older. Data from the current Australian Mesothelioma Registry on asbestos exposure history in Australia is available for 449 subjects diagnosed between July 1, 2010, and April 1, 2015. This asbestos exposure history data show that 60% (n = 268) of cases had probable or possible occupational asbestos exposure, with trade-based jobs being the most frequent sources of occupational asbestos exposure. In addition, out of the 449 cases, 377 were recorded as having probable or possible nonoccupational asbestos exposure. Continuous vigilance toward changes over time in the settings in which people are exposed to asbestos and in the descriptive epidemiology of malignant mesothelioma is recommended to enable a comprehensive understanding of the current and future impact of asbestos-related diseases in Australia.