Enhancing Diagnostic Capabilities for Occupational Lung Diseases Using LIBS Imaging on Biopsy Tissue.

Laser-induced breakdown spectroscopy (LIBS) imaging continues to gain strength as an influential bioanalytical technique, showing intriguing potential in the field of clinical analysis. This is because hyperspectral LIBS imaging allows for rapid, comprehensive elemental analysis, covering elements from major to trace levels consistently year after year. In this study, we estimated the potential of a multivariate spectral data treatment approach based on a so-called convex envelope method to detect exotic elements (whether they are minor or in trace amounts) in biopsy tissues of patients with occupational exposure-related diseases. More precisely, we have developed an approach called Interesting Features Finder (IFF), which initially allowed us to identify unexpected elements without any preconceptions, considering only the set of spectra contained in a LIBS hyperspectral data cube. This task is, in fact, almost impossible with conventional chemometric tools, as it entails identifying a few exotic spectra among several hundred thousand others. Once this detection was performed, a second approach based on correlation was used to locate their distribution in the biopsies. Through this unique data analysis pipeline to processing massive LIBS spectroscopic data, it was possible to detect and locate exotic elements such as tin and rhodium in a patient's tissue section, ultimately leading to a possible reclassification of their lung condition as an occupational disease. This review will thus demonstrate the potential of this new diagnostic tool based on LIBS imaging in addressing the shortcomings of approaches developed thus far. The proposed data processing approach naturally transcends this specific framework and can be leveraged across various domains of analytical chemistry, where the detection of rare events is concealed within extensive data sets.

Historical shift in pathological type of progressive massive fibrosis among coal miners in the USA.

BACKGROUND: Pneumoconiosis among coal miners in the USA has been resurgent over the past two decades, despite modern dust controls and regulatory standards. Previously published studies have suggested that respirable crystalline silica (RCS) is a contributor to this disease resurgence. However, evidence has been primarily indirect, in the form of radiographic features. METHODS: We obtained lung tissue specimens and data from the National Coal Workers' Autopsy Study. We evaluated specimens for the presence of progressive massive fibrosis (PMF) and used histopathological classifications to type these specimens into coal-type, mixed-type and silica-type PMF. Rates of each were compared by birth cohort. Logistic regression was used to assess demographic and mining characteristics associated with silica-type PMF. RESULTS: Of 322 cases found to have PMF, study pathologists characterised 138 (43%) as coal-type, 129 (40%) as mixed-type and 55 (17%) as silica-type PMF. Among earlier birth cohorts, coal-type and mixed-type PMF were more common than silica-type PMF, but their rates declined in later birth cohorts. In contrast, the rate of silica-type PMF did not decline in cases from more recent birth cohorts. More recent year of birth was significantly associated with silica-type PMF. CONCLUSIONS: Our findings demonstrate a shift in PMF types among US coal miners, from a predominance of coal- and mixed-type PMF to a more commonly encountered silica-type PMF. These results are further evidence of the prominent role of RCS in the pathogenesis of pneumoconiosis among contemporary US coal miners.

Nivolumab for treating patients with occupational cholangiocarcinoma.

Tanaka et al. previously reported a case in which nivolumab for recurrent occupational cholangiocarcinoma resulted in complete response persisting for 26 months after discontinuation. Afterward, in that clinical trial, nivolumab was administered to two patients for recurrence. Both patients achieved complete response, suggesting that nivolumab is effective for occupational cholangiocarcinoma.

Musculoskeletal diseases among French military high-speed boat pilots.

In 2016, the French Navy acquired a new high-speed boat, called ECUME. It exposes crewmembers to significant Whole Body Vibrations. This work explores the musculoskeletal diseases among this population. We conducted a retrospective declarative epidemiologic study using anonymous questionnaires. Eighty-four sailors were included. Fifty-six (66.7%) report acute traumas during a nautical raid during the 12 months study period. Sixty (71.4%) report chronic pains, which they associate with their nautical activity. Among them, only 16 (26.7%) have consulted a doctor, but 32 (53.3%) report consuming medication, including 18 through selfmedication. More than half rely to alternatives medicine, especially osteopathy. The traumatic risk of ECUME riding is obvious. Many crewmembers minimize their symptoms, and consult rarely a physician. They give preference to selfmedication and alternative medicines.

A systematic review and meta-analysis on international studies of prevalence, mortality and survival due to coal mine dust lung disease.

BACKGROUND: Coal mine dust lung disease comprises a group of occupational lung diseases including coal workers pneumoconiosis. In many countries, there is a lack of robust prevalence estimates for these diseases. Our objective was to perform a systematic review and meta-analysis of published contemporary estimates on prevalence, mortality, and survival for coal mine dust lung disease worldwide. METHODS: Systematic searches of PubMed, EMBASE and Web of Science databases for English language peer-reviewed articles published from 1/1/2000 to 30/03/2021 that presented quantitative estimates of prevalence, mortality, or survival for coal mine dust lung disease. Review was conducted per PRISMA guidelines. Articles were screened independently by two authors. Studies were critically assessed using Joanna Briggs Institute tools. Pooled prevalence estimates were obtained using random effects meta-analysis models. Heterogeneity was measured using the I2 statistics and publication bias using Egger's tests. RESULTS: Overall 40 studies were included, (31 prevalence, 8 mortality, 1 survival). Of the prevalence estimates, fifteen (12 from the United States) were retained for the meta-analysis. The overall pooled prevalence estimate for coal workers pneumoconiosis among underground miners was 3.7% (95% CI 3.0-4.5%) with high heterogeneity between studies. The pooled estimate of coal workers pneumoconiosis prevalence in the United States was higher in the 2000s than in the 1990s, consistent with published reports of increasing prevalence following decades of declining trends. Sub-group analyses also indicated higher prevalence among underground miners, and in Central Appalachia. The mortality studies were suggestive of reduced pneumoconiosis mortality rates over time, relative to the general population. CONCLUSION: The ongoing prevalence of occupational lung diseases among contemporary coal miners highlights the importance of respiratory surveillance and preventive efforts through effective dust control measures. Limited prevalence studies from countries other than the United States limits our understanding of the current disease burden in other coal-producing countries.

The relationship between occupational exposure to organic solvents and metabolic syndrome in petroleum refinery workers in Tehran, Iran.

AIMS: The rising prevalence of metabolic syndrome has made it a major health concern. Chronic occupational exposure to organic solvents affects different systems of the body. This study aimed to investigate the association between exposure to organic solvents and the prevalence of metabolic syndrome in petroleum refinery workers. METHOD: This study was conducted in 2019-2020 on workers employed in an Iranian petroleum refinery. The demographic and occupational information on the participants was obtained using the interview method. Their height, weight, and blood pressure were measured by the occupational health team, and fasting blood samples were taken from them to measure the paraclinical parameters. RESULTS: In this study, 1009 petroleum refinery workers were analyzed. The prevalence of metabolic syndrome in workers was 20.1% and it was about two times higher in exposed workers (CI 95%: 1.61-3.35) compared to non-exposed ones. Factors associated with the prevalence of metabolic syndrome include age, higher BMI, exercise, and longer exposure to organic solvents. CONCLUSION: Findings of this study suggested that exposure to organic solvents is associated with increased prevalence of metabolic syndrome (the highest association was observed with elevated serum triglycerides). Besides, longer exposure to organic solvents increased the risk of developing metabolic syndrome.

Preliminary Investigation and Imaging Analysis of Early Lung Cancer Screening Among Petroleum Workers in North China.

BACKGROUND: The detection rate of lung nodules has increased significantly among petroleum workers in North China since the low-dose CT (LDCT) screening has been widely carried out. What's more, the number of confirmed early lung cancers is increasing continuously. Therefore, a great deal of concern for the high risk of lung cancer has been shown among petroleum workers. PURPOSE: To improve the screening efficiency and maximize the benefits of the subjects, the current situation of LDCT lung cancer screening should be understood and the imaging characteristics of early lung cancer should be analyzed for petroleum workers in North China. MATERIALS AND METHODS: Firstly, the dynamic changes of LDCT early lung cancer screening for petroleum workers in North China were analyzed in recent years. Then, the survey data of 3121 petroleum workers was compared with that of 1868 non-petroleum workers, which was analyzed. Finally, 91 patients (129 nodular lung cancer) confirmed by pathology were retrospectively analyzed, and the data of which was compared with the clinical features obtained from survey data above. The imaging characteristics and related factors of different subtypes of lung adenocarcinoma were discussed and analyzed. RESULTS: Lung nodules were found in 810 cases (25.95%) out of 3121 petroleum workers; and the surgery was chosen by 42 patients, 38 of whom were confirmed as lung cancer. Compared with the data of screened petroleum workers, there were more older people and more females as well as a higher proportion of people with family malignancy history, and a lower proportion of smoking people in 91 patients with lung cancer. As the pathological grade of tumor nodules increased, the volume and diameter of nodules gradually increased, and the mean density, maximum density and standard deviation of density also increased (p < 0.001). The volume and diameter of nodules were positively correlated with ages (p < 0.05). CONCLUSION: The occurrence of lung adenocarcinoma is closely related to the family history of malignant tumors, and the constituent ratio of young women without a history of smoking increased significantly. At the same time, the quantitative information obtained by using CT images has important value in predicting its pathological subtypes.

Nigral MRI features of asymptomatic welders.

INTRODUCTION: Manganese (Mn)-induced parkinsonism involves motor symptoms similar to those observed in Parkinson's disease (PD). Previous literature suggests that chronic Mn- exposure may increase PD risk, although Mn-induced clinical syndromes are considered atypical for PD. This study investigated whether asymptomatic welders display differences in the substantia nigra (SN), the key pathological locus of PD. METHOD: Brain MRI data and occupational exposure history were obtained in welders (N = 43) and matched controls (N = 31). Diffusion tensor imaging fractional anisotropy (FA; estimate of microstructural integrity) and R2* (estimate of iron and other PD-related brain differences) values in the SN pars compacta (SNc), SN reticulata (SNr), and globus pallidus (GP) were compared between the two groups. The MRI markers of the SN and GP within welders were related to exposure estimates. RESULTS: Compared to controls, welders who had chronic, but low-level, Mn-exposure had similar FA and R2* values in both SN regions (p's > 0.082), but significantly lower FA (p = 0.0013), although not R2* (p = 0.553), in the GP. In welders, FA values in the SN and GP showed a second-order polynomial relationship with cumulative lifetime welding exposure (p's < 0.03). CONCLUSION: Neurotoxic processes associated with Mn-exposure may be different from those in PD when the exposure-level is relatively low. Greater welding duration and level, however, were associated with FA differences in the GP and SN, indicating that welding exposures above a certain level may induce neurotoxicity in the SN, a finding that should be explored further in future studies.

Epidemiological Study of Mortality Among Workers Exposed to Tritium in France.

Workers of the Commissariat for Atomic Energy and Alternative Energy (CEA) may be potentially exposed to tritium over long periods. We aimed to assess the effect of tritium exposure on mortality in a cohort of employees followed by radiotoxicological monitoring. A total of 1,746 employees who worked for at least six months at one of three CEA centers were included between 1962 and 2011 (median follow-up 29.6 years). The cumulative dose of tritium was based on the quantification of tritium present from urinary excretion monitoring data from the beginning of occupational exposure to the end of such exposure or December 2011. Mortality was first compared to that in the French population using the standardized mortality ratio (SMR). Then, mortality risk ratios (RRs) per category of cumulative dose of tritium were estimated using categorical Poisson models adjusted for age at the onset of exposure, age, calendar period, sex, smoking, employment status, CEA center, and taking into account the number of person-years. The main causes of mortality were tumors (48%) and cardiovascular diseases (20%). The comparison of mortality within the cohort to that in the French population highlighted a lower rate for all-cause mortality and that due to cancer, related to the healthy worker effect bias. The regression model showed no effect of cumulative dose on all-cause mortality. The risk of death for most malignancies was positive, but not significant for the higher classes of doses relative to the reference class. The highest risk (not significant) was present for the class of higher doses for tumors of the larynx, trachea, bronchi and lung. The risk was significant for the higher doses for tumors of the pancreas and bladder (based on a limited number of cases: five and six deaths, respectively). Significantly more smokers died from tumors of the respiratory system than non-smokers, as expected. We were unable to show an effect of cumulative tritium dose due to the small size of the cohort and the low exposure level. However, our study underlines the need to continue following tritium-exposed workers and conducting multicenter studies.

Biomonitoring of workers employed in a titanium dioxide production plant: Use of buccal micronucleus cytome assay as noninvasive biomarker to evaluate genotoxic and cytotoxic effects.

We aimed to evaluate whether TiO2 production process induces genotoxic and cytotoxic effects on the first target organ of inhalable particles by a sensitive and noninvasive biomarker of effect. Final aim was to find a useful and suitable tool to assess and manage the risk of TiO2 occupational exposure. We enrolled 40 workers employed in TiO2 production, 5 office workers, and 18 external controls. Buccal micronucleus cytome assay (BMCyt assay) was applied because it allows to evaluate micronucleus (MN), nuclear buds (NB), and broken eggs (BE) indicating the presence of chromosomal instability and gene amplification and binucleated cells (BIN), karyolytic cells (KL), and condensed chromatin (CC) indicating cytokinesis defect or arrest, cell death and apoptosis respectively. We characterized the exposure measuring inhalable and respirable particles by personal monitoring. BMCyt-assay showed in exposed workers compared with external controls a higher value of MN frequency (2.57 vs. 0.05‰, p < .001) and MN positivity, evaluated as percentage of subjects with MN frequency higher than a 1.5‰ cut-off value (52.5 vs. 0%). We also found in exposed workers higher frequency of BE + NB (2.41 vs. 0.22‰, p = .002), BIN (9.45 vs. 8.44‰, p = .047) and CC (1.80 vs. 0.21, p = .001) than in controls. Moreover, we found a relationship between personal monitoring results and presence of MN and other cellular anomalies. This study demonstrates induction of genotoxic and cytotoxic effects on buccal cells of workers involved in TiO2 production, suggesting the suitability of BMCyt assay as tool for risk assessment and management of TiO2 exposure.

Pararamosis: Disease of the Rubber Plantations.

Pararamosis is a medical condition, described in the latex extracting areas of the Amazon (rubber tree regions), resulting from contact with the caterpillar of the Premolis semirufa moth. The disease can present itself in an acute form-similarly to other erucisms (injuries caused by moth larvae in humans)-or in a chronic form, typically characterized by the occurrence of changes in the joints of the hands. Because of its importance, in the context of tropical diseases, the objective of this article was to review the main facets of the disease, emphasizing the different pathogenic aspects of the interaction between the arthropod and man.

Increased Incidence of Thyroid Cancer in Occupational Radiation Epidemiology: Attribution to Screening among Radiation Workers.

In most studies on radiation workers, the incidence of thyroid cancer was determined to be higher than among the general population; this is generally assumed to be due to overdiagnosis through thyroid screening. However, there is a lack of evidence on the association between thyroid screening and increased thyroid cancer incidence in most occupational studies. In this study, we compared thyroid cancer screening rates between the general population and radiation workers with various occupations and examined the relationship between these rates and thyroid cancer incidence. We compared thyroid screening rates between radiation workers and the general population with age- and sex-standardized screening ratios (SSRs) using data from two national surveys conducted during 2015-2017 in Korea, and assessed the correlation between these ratios and age- and sex-standardized incidence ratios (SIRs) for thyroid cancer. Screening rates were higher among radiation workers than among the general population, with an overall SSR of 1.58 (95% confidence interval: 1.54-1.62). When various types of occupations were compared, those with an increased SSR also had an increased SIR. SSRs remained high even when the screening period was restricted to the year preceding the survey (the year after the establishment of guidelines for thyroid cancer screening aimed at reducing overdiagnosis). In conclusion, the increased incidence of thyroid cancer among radiation workers compared to that among the general population can be attributed mainly to increased thyroid screening rates. Additional efforts are needed to reduce unnecessary thyroid cancer screening in occupational populations, particularly in those with better access to healthcare, in terms of clinical rationale and for assessing the true increase in thyroid cancer incidence.

Lung Cancer in the Mayak Workers Cohort: Risk Estimation and Uncertainty Analysis.

The workers at the Mayak nuclear facility near Ozyorsk, Russia are a primary source of information about exposure to radiation at low-dose rates, since they were subject to protracted exposures to external gamma rays and to internal exposures from plutonium inhalation. Here we re-examine lung cancer mortality rates and assess the effects of external gamma and internal plutonium exposures using recently developed Monte Carlo dosimetry systems. Using individual lagged mean annual lung doses computed from the dose realizations, we fit excess relative risk (ERR) models to the lung cancer mortality data for the Mayak Workers Cohort using risk-modeling software. We then used the corrected-information matrix (CIM) approach to widen the confidence intervals of ERR by taking into account the uncertainty in doses represented by multiple realizations from the Monte Carlo dosimetry systems. Findings of this work revealed that there were 930 lung cancer deaths during follow-up. Plutonium lung doses (but not gamma doses) were generally higher in the new dosimetry systems than those used in the previous analysis. This led to a reduction in the risk per unit dose compared to prior estimates. The estimated ERR/Gy for external gamma-ray exposure was 0.19 (95% CI: 0.07 to 0.31) for both sexes combined, while the ERR/Gy for internal exposures based on mean plutonium doses were 3.5 (95% CI: 2.3 to 4.6) and 8.9 (95% CI: 3.4 to 14) for males and females at attained age 60. Accounting for uncertainty in dose had little effect on the confidence intervals for the ERR associated with gamma-ray exposure, but had a marked impact on confidence intervals, particularly the upper bounds, for the effect of plutonium exposure [adjusted 95% CIs: 1.5 to 8.9 for males and 2.7 to 28 for females]. In conclusion, lung cancer rates increased significantly with both external gamma-ray and internal plutonium exposures. Accounting for the effects of dose uncertainty markedly increased the width of the confidence intervals for the plutonium dose response but had little impact on the external gamma dose effect estimate. Adjusting risk estimate confidence intervals using CIM provides a solution to the important problem of dose uncertainty. This work demonstrates, for the first time, that it is possible and practical to use our recently developed CIM method to make such adjustments in a large cohort study.

The clinico-epidemiological characteristics and therapeutic experience of 152 patients with cutaneous sporotrichosis: a 10-year retrospective study from India.

BACKGROUND: Cutaneous sporotrichosis, a subcutaneous mycosis because of Sporothrix schenckii, is sporadic worldwide with local hyperendemic pockets. OBJECTIVES: To study clinico-epidemiological and therapeutic aspects of sporotrichosis in our clinic. METHODS: We retrospectively analyzed medical records of 152 (M:F 52:100) patients with cutaneous sporotrichosis managed during 2010-2019. RESULTS: All patients were involved in agricultural activities, and 63.2% were aged 21-60 years. Women outnumbered men by nearly two times. Fixed and lymphocutaneous sporotrichosis occurred in 54.6% and 43.4% patients, respectively. Only 2% of patients had multifocal sporotrichosis. Only 48% of patients imputed their disease to prior injuries. Extremities, upper in 53.9% and lower in 21% of patients, were mostly involved. Scrotum involvement in one patient was unusual. A mixed inflammatory infiltrate in 38.7%, chronic granuloma formation in 35%, and presence of spores in 48.9% biopsies was noted. S. schenckii grew on Sabouraud's dextrose agar in 40.2% of cases. Treatment with saturated solution of potassium iodide was curative in 76.8% patients, and lesions healed in 2-9 months (average 5.2 months). Metallic taste was experienced by 42.9% of patients. Itraconazole therapy was safe and effective in seven patients, and the response was better when combined with SSKI compared to either drug used alone. CONCLUSION: Cutaneous sporotrichosis mostly affects persons during active years of life. The injuries predisposing to infection are mostly forgotten. Both fixed and lymphocutaneous sporotrichosis involving extremities remain common forms. SSKI alone or in combination with itraconazole is safe and effective treatment. Itraconazole is preferable in patients having preexisting hypothyroidism or intolerance to SSKI.

Occupational bladder cancer: A cross section survey of previous employments, tasks and exposures matched to cancer phenotypes.

OBJECTIVES: Up to 10% of Bladder Cancers may arise following occupational exposure to carcinogens. We hypothesised that different cancer phenotypes reflected different patterns of occupational exposure. METHODS: Consecutive participants, with bladder cancer, self-completed a structured questionnaire detailing employment, tasks, exposures, smoking, lifestyle and family history. Our primary outcome was association between cancer phenotype and occupational details. RESULTS: We collected questionnaires from 536 patients, of whom 454 (85%) participants (352 men and 102 women) were included. Women were less likely to be smokers (68% vs. 81% Chi sq. p<0.001), but more likely than men to inhale environmental tobacco smoke at home (82% vs. 74% p = 0.08) and use hair dye (56% vs. 3%, p<0.001). Contact with potential carcinogens occurred in 282 (62%) participants (mean 3.1 per worker (range 0-14)). High-grade cancer was more common than low-grade disease in workers from the steel, foundry, metal, engineering and transport industries (p<0.05), and in workers exposed to crack detection dyes, chromium, coal/oil/gas by-products, diesel fumes/fuel/aircraft fuel and solvents (such as trichloroethylene). Higher staged cancers were frequent in workers exposed to Chromium, coal products and diesel exhaust fumes/fuel (p<0.05). Various workers (e.g. exposed to diesel fuels or fumes (Cox, HR 1.97 (95% CI 1.31-2.98) p = 0.001), employed in a garage (HR 2.19 (95% CI 1.31-3.63) p = 0.001), undertaking plumbing/gas fitting/ventilation (HR 2.15 (95% CI 1.15-4.01) p = 0.017), undertaking welding (HR 1.85 (95% CI 1.24-2.77) p = 0.003) and exposed to welding materials (HR 1.92 (95% CI 1.27-2.91) p = 0.002)) were more likely to have disease progression and receive radical treatment than others. Fewer than expected deaths were seen in healthcare workers (HR 0.17 (95% CI 0.04-0.70) p = 0.014). CONCLUSIONS: We identified multiple occupational tasks and contacts associated with bladder cancer. There were some associations with phenotype, although our study design precludes robust assessment.

Changes in Spirometry Indices and Lung Cancer Mortality Risk Estimation in Concrete Workers Exposed io Crystalline Silica.

The health of workers in the concrete and cement industries can be at risk due to occupational exposure to silica dust. The purpose of this study was to evaluate the changes of pulmonary parameters and risk of mortality from lung cancer in concrete workers exposed to crystalline silica. This cross-sectional study was performed on 72 male workers exposed to silica at a concrete manufacturing plant in Neyshabur, Iran. Respiratory zone air sampling was performed using the standard NIOSH7602 method using individual sampling pumps and membrane filters. Then, the amount of silica in the samples was determined using the Fourier Transform Infrared technique. The risk of death from lung cancer was determined using Rice et al.'s model. Respiratory indices were measured using a spirometer. Data were analyzed by the SPSS 20 software. Occupational exposure to silica was 0.025 mg/m3 and mortality was estimated to be 7-94 per thousand. All spirometry indices significantly decreased during these 4 years of exposure to silica dust. The respiratory pattern of 22% of the exposed workers was obstructive and this prevalence was significantly higher than the control group. The results showed that although the average occupational exposure to silica in these concrete workers was below the recommended threshold of national and international organizations, their risk of death was significantly higher; and workers' lung indices had significantly decreased over four years. Therefore, appropriate measures should be taken to reduce silica exposure among these workers.

Análisis mineralógico y Registros laborales de amianto, un ejemplo más de su valor / Mineralogical analysis and occupational records of asbestos, one more example of its value

Navarra cuenta con el primer y más exhaustivo Registro de trabajadores expuestos laboralmente a amianto de España. Desde 1996 son remitidos por los Servicios de Prevención y pasan al Servicio Navarro de Salud_Osasunbidea para la vigilancia de patología neumológica relacionada, al jubilarse. Actualmente constan 2858 trabajadores, 395 mujeres y 2463 hombres. La práctica totalidad ya no ocupan puestos de riesgo. Durante años ha ayudado al reconocimiento de la contingencia profesional de los daños. Paradógicamente, en este caso, un trabajador fallecido por cáncer de pulmón con patología intersticial previa, un resultado negativo de necropsia, 425CF (cuerpos ferruginosos)/gr de tejido seco de pulmón se utilizó como argumento para rechazar el origen profesional. Es necesario considerar que un resultado positivo confirma exposición pasada pero uno negativo, si era crisotilo, no la descarta, dada la baja persistencia en tejidos. Una historia laboral detallada y, cuando existan, los Registros han de ser el principal argumento causal

Navarra has the first and most exhaustive Record of workers exposed to asbestos in Spain. Since 1996, referred by the Prevention Services and transferred to the Servicio Navarro de Salud_Osasunbidea for related pulmonary pathology surveillance upon retirement. There are currently 2,858 workers, 395 women and 2,463 men. Almost no longer occupy positions of risk. For years it has helped to recognize the professional contingency of damages.Paradoxically, in this case, a worker who died of lung cancer with previous interstitial pathology, a negative result of an autopsy, 425ferruginous bodies/gr dry lung tissue was used to deny the professional origin. It is necessary to consider that a positive result confirms past exposure but the negative one should not be evaluated when it was chrysotile, given the low temporal persistence in tissues. A reliable work history and, when they exist, the Records must be the main causal argument

Progression of coal workers' pneumoconiosis absent further exposure.

OBJECTIVES: The natural history of coal workers' pneumoconiosis (CWP) after cessation of exposure remains poorly understood. METHODS: We characterised the development of and progression to radiographic progressive massive fibrosis (PMF) among former US coal miners who applied for US federal benefits at least two times between 1 January 2000 and 31 December 2013. International Labour Office classifications of chest radiographs (CXRs) were used to determine initial and subsequent disease severity. Multivariable logistic regression models were used to identify major predictors of disease progression. RESULTS: A total of 3351 former miners applying for benefits without evidence of PMF at the time of their initial evaluation had subsequent CXRs. On average, these miners were 59.7 years of age and had 22 years of coal mine employment. At the time of their first CXR, 46.7% of miners had evidence of simple CWP. At the time of their last CXR, 111 miners (3.3%) had radiographic evidence of PMF. Nearly half of all miners who progressed to PMF did so in 5 years or less. Main predictors of progression included younger age and severity of simple CWP at the time of initial CXR. CONCLUSIONS: This study provides further evidence that radiographic CWP may develop and/or progress absent further exposure, even among miners with no evidence of radiographic pneumoconiosis after leaving the industry. Former miners should undergo regular medical surveillance because of the risk for disease progression.