Parenchymal asbestosis due to primary asbestos exposure among ship-breaking workers: report of the first cases from Bangladesh.

We report for the first time asbestosis among ship-breaking workers of Sitakunda in Bangladesh who were exposed to asbestos during ship-based and beach-based operations for at least 10 years. Asbestosis was present among 35% of workers. Years of work (>20) and forced vital capacity (<80% of predicted) were significantly associated with the disease. Currently, global ship-breaking operations are mainly concentrated in the Indian subcontinent, and Bangladesh has the majority share. Ninety per cent of domestic steel is produced in the ship-breaking operations in Bangladesh and is an important contributor to the economy. It also gives employment to more than 100 000 people. It is imperative to medically check up all the workers for benign and malignant diseases causally related to asbestos among these vulnerable population of workers.

Asbestos related diseases among workers of asbestos processing plants in relation to type of production and asbestos use.

BACKGROUND: Asbestos dust is one of the most dangerous pneumoconiotic and carcinogenic agents. The aim of this study was to assess the occurrence of asbestosis and pleural mesothelioma, depending on asbestos consumption and the type of manufactured products, among former asbestos workers in Poland. MATERIAL AND METHODS: The study subjects included employees of 18 large state-owned asbestos processing enterprises operating in the Polish market in 1945-1998. The study is based on data obtained from asbestos company records and the Central Register of Occupational Diseases data on the cases of asbestosis and mesothelioma for the period from 1970 till 2012 as well as data from Amiantus Programme. The analysis was performed for 5 sectors comprising plants classified according to the products manufactured and applied production technology. RESULTS: In the study period, 2160 cases of asbestosis and 138 cases of mesothelioma were reported. The plants processed a total of about 2 million tons of asbestos, including about 7.5% of crocidolite. Total asbestosis consumption was a strong predictor of the rate of asbestosis incidence (R2 = 0.68, p = 0.055). The highest risk occurrence of asbestosis was observed in the production of textiles and sealing products. Mesothelioma occurred only in plants where crocidolite had been ever processed. CONCLUSIONS: Total asbestos consumption was a strong predictor of the rate of asbestosis incidence. The observation confirms the relationship between exposure to crocidolite and the occurrence of mesothelioma, regardless of the manufactured products, and suggests the absence of such a link for the total volume of asbestos consumption.

[Occupational lung diseases caused by exposure to chrysotile asbestos dust and the preventive measures].

To reveal major principles in system of occupational lung diseases prevention among workers engaged into extraction and usage of chrysotile asbestos, the authors specified main criteria for diagnosis of asbestos-related pulmonary diseases and signs of exposure to chrysotile dust, with identification of risk groups for occupational diseases development. The authors formulated main principles of prevention and rehabilitation for workers with asbestos-related pulmonary diseases. Special attention was paid to harmonization of all medical and technical measures aimed at prevention and liquidation of occupational asbestos-related diseases.

[Exposure to respirable asbestos fibers at various stage of asbestos removal work]. / Narazenie na dzialanie respirabilnych wlókien azbestu podczas róznych etapów prac zwiazanych z usuwaniem materialow azbestowych.

BACKGROUND: Damaged asbestos-containing materials are the source of asbestos fibers released into the outdoor or indoor environment. The highest risk concerns asbestos removal workers, and also other people staying near the performed work. The aim of this project was to analyze and assess air concentrations of asbestos fibers in different types of buildings with asbestos-containing elements under normal operation, as well as during demolition, renovation and maintenance work. MATERIAL AND METHODS: Air samples were collected using stationary and individual aspirators from the breathing zone of people at different locations. The concentration of respirable fibers was determined in accordance with Polish Standard PN-88 Z-04202/02. Air sampling was carried out inside buildings before and during removal of asbestos products, as well as in ambient and indoor air after completing dismantling and repair works. RESULTS: The analysis included 2925 measurements carried out during 2003-2010. Concentrations of respirable asbestos fibers in buildings containing asbestos installations, during their normal operation ranged from 0 to 0.0043 fiber/cm3. Measurements taken at the workposts during removal of asbestos-cement materials showed the average asbestos fiber concentrations of 0.0652 fiber/cm3 and 0.0141 fiber/cm3 for work carried out inside and outside the buildings, respectively. CONCLUSIONS: The concentrations of asbestos respirable fibers inside the buildings containing asbestos elements were low, far beyond the hygiene standard. The highest concentrations of asbestos fibers and the highest percentage of the measurement results exceeding hygiene standard were found at the workposts inside buildings during asbestos removal.

[Exposition markers: mineralogical analysis in the sputum and the bronchoalveolar lavage--asbestos bodies--uncoated fibres]. / Les marqueurs de l'exposition: analyses biométrologiques dans l'expectoration et le LBA - corps asbestosiques - fibres non gainées.

The aim of mineralogical analysis of lung tissue, bronchoalveolar lavage (BAL) and sputum is to characterize individuals' exposure to asbestos fibres by identifying markers of this; asbestos bodies (AB) and uncoated fibres. The techniques of mineralogical analysis, habitually used to identify AB and uncoated fibres, are respectively optical microscopy (OM) and analytical electronic microscopy (EM). Correlations between levels of retention of AB in lung tissue, BAL and sputum have been established and validated threshold values indicating a high probability of significant exposure exist. These results must be interpreted in the context of clinical and occupational information. Mineralogical analysis is not suitable for use in routine medical screening but it can be considered when a source of exposure is not evident from the questionnaire since a positive analysis of BAL or of sputum is highly specific and thus useful to confirm an important retention of asbestos in the lung, which justifies medical follow-up. A negative result does not exclude previous significant asbestos exposure (frequent false negatives occur especially in sputum and biopersistence of chrysotile is lower than for amphiboles). Thus it can be a complementary tool for the assessment of asbestos exposure but its use imposes conditions for the collection and handling of samples.

[Diagnosing and expertizing asbestos-induced occupational diseases]. / Diagnostik und Begutachtung asbestbedingter Berufskrankheiten.

Due to latency periods that can last for decades, asbestos-related diseases show 18 years after the enforcement of the prohibition of asbestos application in Germany their highest numbers. In the centre of attention are asbestos-induced pleural fibroses, mesotheliomas, asbestoses, lung and laryngeal cancer. Diagnosing and expertizing these diseases causes difficulties, is hitherto non-uniform and does frequently not correspond to the current medico-scientific expertise. This induced the German Respiratory Society as well as the German Society of Occupational and Environmental Medicine in cooperation with the German Society of Pathology, the German Radiology Society and the German Society of Otorhinolaryngology, Head and Cervical Surgery, to develop the above mentioned guideline during seven meetings moderated by AWMF. The required thorough diagnosis is based on the detailed recording of a qualified occupational history. Since the sole radiological and pathological-anatomical findings cannot sufficiently contribute to the causal relationship the occupational history recorded by a general physician and a specialist is of decisive importance. These physicians have to report suspected occupational diseases and to advise patients on social and medical questions. Frequently, problems occur if the recognition of an occupational disease is neglected due to a supposedly too low exposure or too few ferruginous bodies or low fibre concentrations in lung tissue. The new S2k directive summarizing the current medico-scientific knowledge is for this reason, for diagnoses and expert opinions as well as for the determination of a reduced capacity for work a very important source of information.

[Implementation of the Amiantus project involving prophylactic medical examinations of the former employees of asbestos processing plants]. / Realizacja programu badan profilaktycznych pracowników bylych zakladów przetwórstwa azbestu "Amiantus".

BACKGROUND: Based on a 11-year implementation of the Amiantus Project, this paper reports the results of prophylactic medical examinations of the former workers of asbestos processing plants. The Project involving employees of 28 former asbestos plants was started by the Ministry of Health in 2000 under the Act on the ban of all products containing asbestos. MATERIAL AND METHODS: Preventive examinations, continued in 13 centers of occupational medicine throughout the whole territory of Poland, have been coordinated by the Nofer Institute of Occupational Medicine in Lodz (NIOM). During the examinations, a specific Examination Form is filled-in by a physician. The Form is then sent to NIOM for monitoring health effects in the population covered by the Project. The results obtained by analyzing the lung radiological images are recorded in the Examination Form according to the ILO 1980 classification of pneumoconiosis. The diagnosis of the asbestos-related pathologies is based on the Helsinki criteria. RESULTS: During the years 2000-2010, altogether 6,853 people were involved in the Project, and they were subjected to a total of 18,955 preventive examinations. Asbestosis was diagnosed in 1475 people, representing 21% of all respondents, lung cancer in 68 and mesothelioma in 40 people. Pleural radiographic changes were observed in 3027 (44%) patients, pulmonary parenchymal opacities in 4086 (60%) patients. The analysis showed that the asbestos-related pathologies were most frequent in the group of former employees of asbestos-cement plants. This group was also characterized by an age-, tenure-, and latency-related increasing trend in the prevalence of silicosis and the frequency of radiographic lesions in the lungs of those subjects. CONCLUSIONS: The continuation of the examinations of former workers of asbestos processing industry has improved the detection of pathologies associated with exposure to asbestos and enabled undertaking an appropriate preventive action. The growing percentage of poorer radiography results reflects the progressive development of pathological processes in the respiratory system of people occupationally exposed to asbestos dust in the past.

[Pulmonary concentration of asbestos fibers in steel workers with pleural mesothelioma]. / Concentrazione polmonare di fibre di amianto in lavoratori siderurgici affetti da mesotelioma pleurico.

The asbestos fibre burden of the lung has been used in the past as a biological indicator of cumulative exposure to the mineral so much so that in 1997 reference limits even for non-occupationally exposed people have been proposed. This kind of analysis was performed on groups of workers of different type of industries and allowed to achieve a qualitative-quantitative estimate of past exposure to asbestos, even in absence of exposure estimates by environmental monitoring. An important example is the steel industry where asbestos was widely used in the past, but for which there are not available exposure estimates of workers. Among the mesothelioma cases collected by the Mesothelioma Registry of the Province of Brescia from 1980 to present there are 55 workers who spent at least 5 years in steel industry, on a total of 289 cases classified as asbestos exposed (19%). For 8 subjects who worked in steel mills and production of electrical steel pipes, of which 4 in the same plant, lung tissue samples were available for the asbestos fibres burden analysis (7 samples coming from autopsies and 1 from extra-pleural pneumonectomy). In all cases the diagnosis was given with histological analyses supplemented with immunohistochemistry. In 7 cases autopsied the diagnosis was confirmed. The work histories have been reconstructed in detail through the interview process, inclusive of details of duties performed. The asbestos fibre burden analyses showed a range of concentrations between 260,000 and 11,000,000 ff per grams of dry tissue; the concentration of amphiboles was much higher than that of chrysotile. The highest body burden was detected in the maintenance workers of the same plant in witch a cluster of malignant mesothelioma was observed. In conclusion, this study illustrates the results of asbestos fibres burden analyses in subjects where exposure to asbestos is sure but not quantifiable. The results showed also that these concentrations can reach values that overlap with those found in asbestos-cement workers and in asbestos-textile workers. These data suggest to consider the cases of mesothelioma occurred in the steel workers at least as "possible" exposure, even in the absence of adequate information on the circumstances of contact with asbestos. This study, although based on a small number of cases, is the only one ever held in Italy on workers in this sector.

[Prophylactic examinations of workers formerly employed in asbestos processing plants: outcome of the Amiantus project in 2000-2004]. / Badania profilaktyczne bylych pracowników zakladów przetwórstwa azbestu--wyniki realizacji programu Amiantus w latach 2000-2004.

BACKGROUND: Prophylactic examinations of workers formerly employed in asbestos processing plants were performed by virtue of the Act, dated 19 June 1997, putting a ban on the production of asbestos-containing products. To enforce the provisions of the Act, the Ministry of Health has initiated the Amiantus project implemented by 13 Occupational Medicine Centers throughout the country and coordinated by the Nofer Institute of Occupational Medicine (IMP) in Lódz. MATERIAL AND METHODS: All the Centers perform diagnostic procedures according to the same criteria (clinical, radiological, spirometric and histological), based on the 1997 Helsinki criteria, to diagnose asbestos-related diseases. A specific "Examination Form", developed for the needs of the Amiantus project, is completed by an occupational physician during examinations and sent to the IMP, where health effects in the whole population covered by the project are monitored. Periodical medical examinations are performed at least every three years and they include: general examination, chest x-ray, resting spirometric examination and supplementary examinations (e.g., resting gasometric examination) or other diagnostic examinations if necessary (e.g., computed tomography). RESULTS: Owing to the project implementation, it was possible to collect in the database information on 5466 persons who underwent 8763 prophylactic examinations in 2000-2004. Of the total population examined during a five-year period, occupational disease was certified in 728 (13%) persons. Asbestosis was diagnosed in 790 persons, lung cancer in 19 persons and pleural mesothelioma in 12 persons. Pleural changes in x-ray imaging were found in 1662 (30%) persons and opacities in pulmonary parenchyma in 2088 (38%) persons. Having compared these results with those from previous examinations, the total health condition deterioration was observed in 882 (16%) persons, including worsening of the lung x-ray imaging in 512 (9%) persons. An analysis showed the highest incidence of asbestos-related pathologies in workers of asbestos-cement plants. The collected data also confirmed an upward trend in the incidence of asbestosis and changes in the lung x-ray imaging related to age, duration of employment and latency. CONCLUSION: The implementation of the Amiantus project has contributed to an increased detection of pathologies related with exposure to asbestos fibers. A growing proportion of radiograms, which indicate worsening of health condition provides evidence that morbid processes in the respiratory system are progressing in persons who in the past were occupationally exposed to asbestos dust.

The clinical diagnosis of asbestosis in this century requires more than a chest radiograph.

Asbestosis can cause significant impairment and even death. It is also a well-recognized risk factor for the development of lung cancer. However, asbestosis is usually diagnosed on clinical grounds without the aid of pathology. Many physicians and researchers believe that in asbestos-exposed individuals with adequate latency, chest radiographic findings that are compatible with asbestosis are sufficient for the diagnosis. In order to determine whether this approach is reasonable, the positive predictive value of the chest radiograph for the diagnosis of pathologic asbestosis must be determined. This requires information about the prevalence of asbestosis, and the sensitivity and specificity of the chest radiograph in its diagnosis. In this article, the sensitivity and specificity of the chest radiograph in diagnosing asbestosis is determined from a literature analysis. The prevalence of asbestosis among present-day cohorts, such as construction workers and petrochemical workers, is assessed based on the relative risk of lung cancer in patients with asbestosis and the overall relative risk of lung cancer in these occupationally asbestos-exposed cohorts. The results indicate a positive predictive value for abnormal chest radiograph findings alone to be significantly < 50%. Therefore, the chest radiograph is inadequate as the sole clinical tool to be used to diagnose asbestosis in these cohorts. However, when rales and a low diffusing capacity of the lung for carbon monoxide are also present, the diagnosis of asbestosis on clinical grounds can be made with reasonable confidence.

Asbestos bodies in bronchoalveolar lavage fluid and sputum.

The aim of the study was to determine the concordance of asbestos body (AB) detection in sputum and bronchoalveolar lavage fluid (BALF). AB were detected in the BALF of 110 former or current asbestos workers with medium weak exposure level and, for 65 subjects, in sputum. Several spontaneous sputum samples were taken from each subject. AB prevalence in BALF was rather low (48.2%) especially in subjects with former chrysotile exposure (32.5%). AB prevalence was lower in smokers (40.9%) and ex-smokers (40.7%) than in non-smokers (68.7%). In the sub-group, who underwent both sputum and BALF examination, the concordance of AB detection was observed only in 56.8% of the cases. Neither of the two methods had significant prevalence over the other but were complementary, as both are useful in increasing the probability of AB detection.