Histological findings and lung dust analysis as the basis for occupational disease compensation in asbestos-related lung cancer in Germany.

OBJECTIVES: This study has researched the significance of histologically raised findings and lung dust analyses in the context of claiming the recognition of and thus compensation for an asbestos-associated occupational disease. MATERIAL AND METHODS: For this approach, all findings from the German Mesothelioma Register in 2015 that included lung dust analyses were evaluated and were compared with information on asbestos fiber exposure at work based on fiber years, and with the results of radiological findings. RESULTS: For 68 insured persons, recognition of an asbestos-induced lung disease according to Section 4104 of the German Ordinance on Occupational Diseases (Berufskrankheitenverordnung - BKV) could be recommended solely on the basis of the histological examinations of lung tissues and complementary lung dust analyses. Neither did the calculation of the cumulative asbestos dust exposure at work yield 25 fiber years, nor could bridge findings (e.g., plaques) be identified. In addition, the autopsies of 12 patients revealed plaques that had not been diagnosed during radiological examinations. These results show that - irrespective of the prescribed working techniques and radiological diagnosis - pathological/anatomical and histological diagnostics are often the only way for the insureds to demonstrate the causal connection between asbestos and their disease. Even after long intervals of up to 40 years post last exposure, the asbestos fibers would still be easily detectable in the lung tissues evaluated. CONCLUSIONS: Whenever suitable tissue is available, it should be examined for mild asbestosis with the aid of a lung dust analysis. Otherwise there is a risk that an occupational disease is wrongfully rejected. In the context of health insurance, the lung dust analysis and the resulting proof of the presence of asbestosis often constitute one option of providing evidence of an occupational disease. Int J Occup Med Environ Health 2018;31(3):293-305.

Evaluation of the dark-medium objective lens in counting asbestos fibers by phase-contrast microscopy.

A Japanese round-robin study revealed that analysts who used a dark-medium (DM) objective lens reported higher fiber counts from American Industrial Hygiene Association (AIHA) Proficiency Analytical Testing (PAT) chrysotile samples than those using a standard objective lens, but the cause of this difference was not investigated at that time. The purpose of this study is to determine any major source of this difference by performing two sets of round-robin studies. For the first round-robin study, 15 AIHA PAT samples (five each of chrysotile and amosite generated by water-suspended method, and five chrysotile generated by aerosolization method) were prepared with relocatable cover slips and examined by nine laboratories. A second round-robin study was then performed with six chrysotile field sample slides by six out of nine laboratories who participated in the first round-robin study. In addition, two phase-shift test slides to check analysts' visibility and an eight-form diatom test plate to compare resolution between the two objectives were examined. For the AIHA PAT chrysotile reference slides, use of the DM objective resulted in consistently higher fiber counts (1.45 times for all data) than the standard objective (P-value < 0.05), regardless of the filter generation (water-suspension or aerosol) method. For the AIHA PAT amosite reference and chrysotile field sample slides, the fiber counts between the two objectives were not significantly different. No statistically significant differences were observed in the visibility of blocks of the test slides between the two objectives. Also, the DM and standard objectives showed no pattern of differences in viewing the fine lines and/or dots of each species images on the eight-form diatom test plate. Among various potential factors that might affect the analysts' performance of fiber counts, this study supports the greater contrast caused by the different phase plate absorptions as the main cause of high counts for the AIHA PAT chrysotile slides using the DM objective. The comparison of fiber count ratios (DM/standard) between the AIHA PAT chrysotile samples and chrysotile field samples indicates that there is a fraction of fibers in the PAT samples approaching the theoretical limit of visibility of the phase-contrast microscope with 3-degree phase-shift. These fibers become more clearly visible through the greater contrast from the phase plate absorption of the DM objective. However, as such fibers are not present in field samples, no difference in counts between the two objectives was observed in this study. The DM objective, therefore, could be allowed for routine fiber counting as it will maintain continuity with risk assessments based on earlier phase-contrast microscopy fiber counts from field samples. Published standard methods would need to be modified to allow a higher aperture specification for the objective.

A Case Study of a Foundry Worker with Localized Asbestosis: an Uncommon Occurrence in Korea / 대한산업의학회지

BACKGROUND: Foundry workers are known to be exposed to silica and have an increased risk of silicosis. There are also reports that state these foundry workers were associated with asbestos-related change in the X-ray results of the lungs. This report discusses a case of localized asbestosis developed in a foundry worker who worked in 12 Korean foundries. CASE REPORT: A 49-year-old man who worked at molding and melting for 30 years, presented with sore throat, cough and yellow sputum for 1 month. From physical and clinical examination, pulmonary tuberculosis was highly suspicious; therefore, he was medicated for 6 months. After tuberculosis medication, the radiological finding was reactivation of tuberculosis, and an asbestos body was detected at a transbronchial lung biopsy. During an operation, operators found multiple palpable masses and bullae localized in the right upper lobe (RUL) and performed right upper lobectomy and right middle lobe wedge resection. Using hematoxylin-eosin stain and iron stain, we could detect asbestos bodies by light microscopy. We analyzed the asbestos fiber burden in dry lung tissue by transmission electron microscopy with energy dispersive X-ray spectrometer (TEM-EDX). The fiber type was chrysotile and the fiber burden was 23.26x106 fiber/g dry lung. DISCUSSION: This case study of a foundry worker with localized asbestosis is uncommon in Korea. We found an occupational relationship between the foundry worker and localized asbestosis through various investigative techniques such as measurements taken at his working environment, clinical, radiological and pathological examination of the foundry worker and mineralogical examination of the asbestos fiber.

A Case Study of a Foundry Worker with Localized Asbestosis: an Uncommon Occurrence in Korea / 대한산업의학회지

BACKGROUND: Foundry workers are known to be exposed to silica and have an increased risk of silicosis. There are also reports that state these foundry workers were associated with asbestos-related change in the X-ray results of the lungs. This report discusses a case of localized asbestosis developed in a foundry worker who worked in 12 Korean foundries. CASE REPORT: A 49-year-old man who worked at molding and melting for 30 years, presented with sore throat, cough and yellow sputum for 1 month. From physical and clinical examination, pulmonary tuberculosis was highly suspicious; therefore, he was medicated for 6 months. After tuberculosis medication, the radiological finding was reactivation of tuberculosis, and an asbestos body was detected at a transbronchial lung biopsy. During an operation, operators found multiple palpable masses and bullae localized in the right upper lobe (RUL) and performed right upper lobectomy and right middle lobe wedge resection. Using hematoxylin-eosin stain and iron stain, we could detect asbestos bodies by light microscopy. We analyzed the asbestos fiber burden in dry lung tissue by transmission electron microscopy with energy dispersive X-ray spectrometer (TEM-EDX). The fiber type was chrysotile and the fiber burden was 23.26x106 fiber/g dry lung. DISCUSSION: This case study of a foundry worker with localized asbestosis is uncommon in Korea. We found an occupational relationship between the foundry worker and localized asbestosis through various investigative techniques such as measurements taken at his working environment, clinical, radiological and pathological examination of the foundry worker and mineralogical examination of the asbestos fiber.

Asbestos and Non-Asbestos Fiber Content in Lungs of Autopsied Subjects in Pohang with no Known History of Occupational Asbestos Exposure / 예방의학회지

OBJECTIVES: To obtain reference values for the pulmonary asbestos and non-asbestos fiber contents of residents in Korea and to compare them with similar results from Japan. METHODS: The autopsied lung specimens from 22 deceased people (20 males and 2 females) in Pohang, without any known occupational history of asbestos exposure, were analyzed for incidence of asbestos and non-asbestos fibers by transmission electron microscopy with energy dispersive X-ray analysis after using low temperature ashing procedures. RESULTS: Chrysotile fiber (46.2%) was the major fiber type found in the lungs of the subjects. The asbestos fiber concentrations found in males and females were 0.09x106 fibers/(g of dry lungs) and 0.30x106 fibers/(g of dry lungs), respectively, showing a geometric mean concentration 0.09x106 fibers/(g of dry lung tissue), due to the predominance of males in the sample. The non-asbestos fiber contents in males and females were 4.61x106 fibers/(g of dry lungs) and 17.79x106 fibers/(g of dry lungs), respectively, with a geometric mean concentration 5.21x106 fibers/(g of dry lung tissue). CONCLUSIONS: Residents in Pohang had significantly lower levels of both asbestos and non-asbestos fibers than urban residents in Korea. Furthermore, Koreans had significantly lower levels of both asbestos and non-asbestos fibers than Japanese.