Occupational respiratory cancer and exposure to asbestos: A case-control study in a cohort of workers in the electricity and gas industry

Cancers of the pleura, lung, and larynx between 1978 and 1989 among active male workers of Electricité de France-Gaz de France were studied in association with asbestos exposure using a case-control design nested within the cohort of workers of the company. The cohort included about 1,400,000 person-years, corresponding to a mean of 117,000 men per year. Exposure to asbestos and to some potential occupational confounders selected among agents from groups I, IIa, and IIb of the International Agency for Research on Cancer was assessed by a job-exposure matrix specific to the company. During the observation period, 12 cases of pleural cancer, 310 cases of lung cancer, and 116 cases of larynx cancer were registered in the cancer register of the company social security department. Four controls per case, matched for year of birth, were randomly selected among the cohort. Conditional logistic regression was used to estimate the odds ratios. A first analysis was conducted in order to assess the validity of the job-exposure matrix by investigating already known relationships between asbestos exposure and asbestosis. For asbestosis, a strong exposure-response relation was found with an odds ratio (OR) of 57.4 [95% confidence interval (CI): 17.0–194.0] in the highest exposure group. There was an elevated risk of pleural cancer (OR, 4.8, CI, 1.2–19.8). For lung cancer, significant ORs of 2.0 (CI, 1.3–3.2) and 1.9 (CI, 1.2–3.0) were found among the two highest cumulative exposure groups; adjustement for confounders slightly decreased the ORs. Squamous cell neoplasm of the lung was associated with asbestos exposure. The association between larynx cancer and asbestos exposure showed a tendency towards a nonsignificant increase in ORs in the highest cumulative exposure categories; this tendency disappeared when adjusting for occupational confounders. This study showed that occupational exposure to asbestos could increase the risk of pleural and lung cancer in a sector in which exposure levels are not considered to be high compared with other industrial settings.     

Cancer in ex‐asbestos cement workers in Israel, 1953–1992

A cohort of 3,057 male workers employed in an asbestos‐cement plant using 90% chrysotile‐10% crocidolite, located in Northern Israel, was followed from 1953–1992 for incidence and mortality from cancer. In the years 1978–1992, the cohort had an elevated risk for all malignant neoplasms combined (n > 153, SIR > 117, ns), lung cancer (n > 28, SIR > 135, ns), mesothelioma (n > 21; SIR >5000, p > .0001), unspecified pleural cancer (n > 5; SIR > 278 , P > .0001), and liver cancer (n > 7, SIR 290, ns). Risks for colo‐rectal (n > 19; SIR > 79, ns), bladder (n = 12, SIR 69) and renal cancers (n > 5, SIR 104) were less than expected. Risk for mesothelioma showed a sharp risk gradient with duration of exposure, increasing from 1 per 625 for those employed less than 2 years to 1 per 4.5 workers employed over 30 years. The ratio of mesothelioma to excess lung cancer cases was 2.9 to 1, or 3.6 to 1, if pleural cases of unspecified origin were included; the pleura to peritoneum ratio of verified mesothelioma cases was 20 to 1. This atypically high ratio of mesothelioma to excess lung cancer cases is suggested to be the combined result of high past asbestos exposures in the workers and their low prior risk for lung cancer, and possibly, relatively early smoking cessation in relation to asbestos exposure. Am. J. Ind. Med. 35:1–8, 1999. © 1999 Wiley‐Liss, Inc.     

Lung cancer risk in past asbestos workers a few decades after exposure cessation and prospects for screening

To ascertain whether the current risk of lung cancer in former asbestos workers was higher than in the general population, 1,557 past asbestos workers were recruited during statutory health examinations (from 2000 onward) and followed up for mortality. Standardized mortality ratios (SMRs) were calculated. Poisson regression was used to adjust the rate ratios (RRs) for confounders. SMR was about 1.00 in workers with or without pleural plaques and 4.62 (95% confidence interval: 0.61–18.1) in those with asbestosis. Adjusted RRs for lung cancer were 4.70 (0.99–22.5) for asbestosis, 4.35 (0.97–19.5) for former smokers, 6.82 (1.38–34.4) for current smokers. Currently, lung cancer mortality in past asbestos workers is similar to the general population, probably because workers more exposed /more susceptible could have died from lung cancer before the beginning of follow-up.     

Use of an Asbestos Exposure Score and the Presence of Pleural and Parenchymal Abnormalities in a Lung Cancer Case Series

Abstract

To assess whether there was an association between asbestos exposure and abnormalities on chest x-rays or CT scans, chest radiographs and CT scans of 103 asbestos-exposed patients with known lung cancer were reviewed for pleural or parenchymal abnormalities. Asbestos exposure was assessed using an asbestos exposure index that integrated time and intensity of reported exposure via a weighting scheme. Chest CT scans were clearly more sensitive in detecting pleural or parenchymal abnormalities than were standard PA chest x-rays. Furthermore, there was a significant correlation between higher asbestos exposure index scores and abnormalities on CT scans. Multivariable logistic regression models were used to investigate the relationship between the asbestos exposure index score and pleural or parenchymal abnormalities after adjusting for gender, pack-years of smoking, and cell type. None of these variables was associated with abnormalities on chest x-rays or CT scans. An asbestos exposure score > 10 was associated with pleural or parenchymal abnormalities (OR = 4.93; 95% CI 1.05–23.12). The results suggest that assessment of asbestos exposures by means of an algorithm-based index can classify the exposures accurately for epidemiologic studies.     

Asbestos Bodies in Normal Lung of Western Mediterranean Populations with No Occupational Exposure to Inorganic Dust

The aim of this study was to determine the following: (a) asbestos body count in lung tissue of different western Mediterranean populations; (b) the association, if any, of urban industrial residence with higher lung tissue asbestos body counts in this geographical area; and (c) the risk factor that environmental asbestos exposure posed for lung cancer in our population. Lung-tissue samples were studied in three groups of subjects from the general population: (1) group A comprised 18 patients from Barcelona's urban industrial area (mean age = 62.2 y, standard deviation [SD] = 13.6); (2) group B comprised 16 patients who lived in a rural area of Albacete in the south of Spain (mean age = 62.2 y, SD = 13.7); and (3) group C comprised 8 patients who had been diagnosed with lung cancer, who lived in or near Barcelona, and who had never been exposed occupationally to asbestos (mean age = 62.1 y, SD = 7.4). A wet lung/dry lung weight ratio was determined. In group A, asbestos bodies were observed in 9 of 18 (50%) subjects, and asbestos bodies numbered 52.35 per g dry lung (SD = 101.72) (upper limit of normality [higher value] = 430.12 asbestos bodies per g dry lung). In group B, asbestos bodies were observed in 2 of 16 (12.5%) subjects, and asbestos bodies numbered 5.37 per g dry lung (SD = 8.79) (upper limit normality = 35.15 asbestos bodies per g dry lung). In group C, we observed asbestos bodies in 2 of 8 subjects (25.0%), and asbestos bodies numbered 20.59 per g dry weight (SD = 24.10). Comparison between groups A and B indicated small differences in the prevalence of asbestos bodies (i.e., Barcelona 50%, Albacete 12.5%; p = .057 [chi-square test]), as well as small differences in asbestos body counts (i.e., asbestos bodies per g dry lung; Mann-Whitney U-test, p < .001). The results of these comparisons evidenced a higher exposure to asbestos in the urban industrial environment. No statistically significant differences were found between groups A and C (chi-square test/Mann-Whitney U-test: p > .05). We concluded that, in western Mediterranean populations, normal lung asbestos body counts were higher in urban industrial inhabitants than in rural inhabitants; however, in both populations, there was a low prevalence of asbestos bodies. Our results did not suggest that environmental exposure to asbestos played a role in the pathogenesis of lung cancer in subjects who had never been exposed occupationally to asbestos and who had lived in western Mediterranean areas.     

Exposure to asbestos and lung and pleural cancer mortality among pulp and paper industry workers

We studied the mortality from lung and pleural cancers in a cohort of 62,937 male workers employed for at least 1 year in the pulp and paper industry in 13 countries during 1945 to 1996. Mill departments were classified according to probability and level of exposure to asbestos on the basis of available dust measurements and mill-specific information on exposure circumstances. Thirty-six percent of workers were classified as ever exposed to asbestos. Standardized mortality ratios of lung cancer were 0.99 (95% confidence interval [CI], 0.90 to 1.08) among unexposed and 1.00 (95% CI, 0.90 to 1.11) among ever exposed workers. The number of pleural cancer deaths among unexposed workers was 10; that among exposed workers was 14, most of which occurred among maintenance workers. In internal analyses, a trend in mortality from either neoplasm was suggested for estimated cumulative exposure to asbestos, weighted for the individual probability of exposure within the department and for duration of exposure (relative risk for lung cancer for 0.78+ f/cc-years, as compared with < or = 0.01 f/cc-years: 1.44; 95% CI, 0.85 to 2.45; corresponding relative risk for pleural cancer: 2.43; 95% CI, 0.43 to 13.63). Despite a possible nondifferential misclassification of exposure and outcome, this study suggests that the carcinogenic effect of asbestos can be detected among workers employed in industries such as the pulp and paper industry, in which it is not considered to be a major hazard.     

Reforming foodservice in elderly care: National actions and local outcomes

Aim

The aim was to explore the outcome, on a local level, of steering, organisation and practices of elderly care foodservice by Swedish municipalities, and changes relative to national actions.

Methods

A survey using a web‐based questionnaire about elderly care foodservice targeting all Swedish municipalities (n = 290) was conducted in 2006 and 2013/2014. The questionnaire included the topics: organisation of foodservice, its practice in elderly care and steering devices such as guidelines and policies. Based on the share of a rural population, municipalities were divided into groups: rural (≥50%), urban (<50%) and city (≤20%).

Results

The response rate from municipalities was 80% in 2006 and 56% in 2013/2014; 45% participated in both surveys. The results showed increased use of local food policies (P = 0.03) and meal choice (P < 0.001), while access to clinical/community dietitians declined (P = 0.01) between the surveys. In home‐help services, daily delivered cook‐serve meals declined (P < 0.001) and chilled meals delivered three times a week increased (P = 0.002) between the surveys. City municipalities used private foodservice organisations the most (P < 0.001), and reported reduced use of cook‐serve systems in favour of chilled. In rural municipalities, the use of public providers (98%) and a cook‐serve system (94%) were firmly established. Urban municipalities were placed between the other groups.

Conclusions

National actions such as soft governance and benchmarking appear largely to determine local level outcomes. However, conditions for adapting these measures vary between municipality groups. While efficiency enhancing trends were prominent, questions remain whether national actions should be expanded beyond performance to also examine their consequences.     

Role of occupational asbestos exposure in Hungarian lung cancer patients

Objective: What is the frequency of occupational asbestos exposure among patients suffering from malignant respiratory tumours and how many of these tumours are associated with asbestos in Hungary? Methods: An internationally established questionnaire with 29 questions, covering the most characteristic activities of asbestos exposure at the workplace was completed for 300 patients with respiratory malignancies, i.e. 297 patients with lung cancer and three with mesothelioma of the pleura. From the questionnaire, the smoking habits were estimated and cumulative asbestos exposure was assessed in fibre-years. Additionally, lung X-rays were classified and the national data on the incidence of malignant pleura mesothelioma were analysed. Results: A cumulative asbestos exposure of 25?fibre-years or more was detected in 11 patients with lung cancer (4%) and in each of the three patients with pleural mesothelioma (100%). In a further 72 patients (24%), cumulative occupational asbestos exposure was assessed as below 25?fibre-years (between 0.01 and 23.9?fibre-years). In this group, car and truck mechanics, and installation and construction workers using asbestos-cement were registered. Among patients with an asbestos exposure of 25?fibre-years or more, six asbestos-cement production workers were observed, among them the three mesothelioma cases. A weak but significant association between positive X-ray findings and exposure estimates could be demonstrated. Additionally, results of the lung tissue fibre counts by scanning transmission electron microscopy were available for 25 of the lung cancer patients. A good correlation was observed between the asbestos fibre counts and the assessment of cumulative asbestos exposure. In Hungary, 84 cases of pleural mesothelioma were registered in 1997 and 73 in 1998. These numbers correspond to an annual incidence of about one new case per 100,000 inhabitants older than 15?years. Conclusions: The annual incidence of lung cancer in Hungary is about 6,000. Since in our series of lung cancer patients about 4% were observed, which could be accepted as representing occupational disease because of a cumulative exposure to 25?fibre-years or more, the annual asbestos related lung tumour incidences may be estimated to be approximately 150 or more. The proportion of nearly two estimated cases of lung cancer per case of pleural mesothelioma corresponds to international experience. Up to now, lung cancer cases only exceptionally have been registered as occupational diseases, i.e. they were seriously under-diagnosed in Hungary. For improving this situation, diagnostic assistance by a self-interview with a questionnaire covering the working history for all newly diagnosed lung cancer patients would be helpful.     

Inorganic fibres in the lung tissue of Hungarian and German lung cancer patients

Objective: To ascertain the lung burden of asbestos fibres in Hungarian lung cancer patients in comparison with the cumulative asbestos exposure estimated from the occupational history. Methods: For 25 Hungarian lung cancer patients, lung tissue fibre analysis was performed by scanning transmission electron microscopy (STEM) and counting of ferruginous bodies (FBs) by light microscopy. Cumulative asbestos exposure in fibre-years was assessed from a standardised occupational history using the report “fibre years” of the German Berufsgenossenschaften. Results: Median and maximum concentrations of fibres longer 5 μm per gram dry lung tissue (g dry) were 0.03 and 7.38 million fibres/g dry for chrysotile, 0.00 and 0.21 million fibres/g dry for amphibole and 0.22 and 0.62 million fibres/g dry for other mineral fibres (OMFs). The maximum values were observed in one patient for whom a high asbestos exposure was evident in advance from the occupational history. Conclusions: In comparison with reference values obtained by the same method for German patients with no indication of workplace asbestos exposure, increased concentrations of more than 0.2 million chrysotile fibres/g dry were obtained for six of the 25 Hungarian patients (24%). For one of them, the second highest estimate of a workplace exposure of 60 fibre-years and the highest tissue concentration of 7.38 million chrysotile fibres/g dry substantiate a high probability of a causal relationship to asbestos. A further comparison can be made with the results for 66 German patients treated by surgical lung resection for a disorder other than mesothelioma, mainly lung cancer. For the Hungarian lung cancer patients, similar amounts of chrysotile but distinctly lower amounts of amphibole fibres and distinctly higher amounts of OMFs were observed. A correlation between exposure estimates from occupational history and concentration of fibres in the lung tissue was observed for amphibole (Spearman: R=0.66, P < 0.001, Pearson: R=0.50, P=0.01) and for chrysotile (Pearson: R=0.48, P=0.02). Received: 3 May 2000 / Accepted: 14 September 2000     

2008-2018年中国4省重点地区肝癌死亡趋势及去死因期望寿命分析

目的分析2008-2018年中国4省重点地区人群肝癌死亡率变化趋势, 探讨肝癌死亡对期望寿命变化的影响程度, 为评估该地区综合防控效果、促进卫生资源合理配置提供数据支撑。方法基于2008-2018年中国CDC全国死因监测数据库中4省重点地区死因数据, 分析该地区肝癌死亡率、去死因期望寿命(CELE)、去死因期望寿命增长年(PGLEs), 采用Joinpoint 4.9.0.0软件计算平均年度变化百分比(AAPC), 采用Arriaga分解法估计各年龄组肝癌死亡率变化对期望寿命变化的贡献情况。结果 2008-2018年4省重点地区肝癌标化死亡率整体呈下降趋势(AAPC=-4.37%, P<0.001)。肝癌死亡率变化对期望寿命增长起积极作用, 贡献值0.240岁, 贡献度5.62%;其中, 积极作用最大的是45～49岁年龄组(0.041岁, 0.96%), 消极作用最大的是50～54岁年龄组(-0.015岁, -0.35%)。与2008年相比, 2018年4省重点地区人群期望寿命增长4.27岁(AAPC=0.59%, P<0.001), 肝癌CELE增长4.20岁(AAPC=...     

Attitudes toward tobacco cessation and lung cancer screening in two South African communities

ABSTRACT

Among men in South Africa, the prevalence of tobacco smoking is as high as 33%. Although smoking is responsible for most lung cancer in South Africa, occupational and environmental exposures contribute greatly to risk. We conducted a tobacco and lung cancer screening needs assessment and administered surveys to adults who smoked >100 cigarettes in their lifetime in Johannesburg (urban) and Kimberley (rural). We compared tobacco use, risk exposure, attitudes toward and knowledge of, and receptivity to cessation and screening, by site. Of 324 smokers, nearly 85% of current smokers had a <30 pack-year history of smoking; 58.7% had tried to stop smoking ≥1 time, and 78.9% wanted to quit. Kimberley smokers more often reported being advised by a healthcare provider to stop smoking (56.5% vs. 37.3%, p=0.001) than smokers in Johannesburg but smokers in Johannesburg were more willing to stop smoking if advised by their doctor (72.9% vs. 41.7%, p<0.001). Findings indicate that tobacco smokers in two geographic areas of South Africa are motivated to stop smoking but receive no healthcare support to do so. Developing high risk criteria for lung cancer screening and creating tobacco cessation infrastructure may reduce tobacco use and decrease lung cancer mortality in South Africa.     

Prevalence of and Factors Associated with Sarcopenia in Korean Cancer Survivors: Based on Data Obtained by the Korea National Health and Nutrition Examination Survey (KNHANES) 2008–2011

Using a representative dataset from the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011, we analyzed anthropometric and dual-energy X-ray absorptiometry (DXA)-determined body composition findings for 493 cancer survivors (mean age a61.1 ± 12.6 years; 35.7% male). A much higher proportion of men (30.1%) than women (0.6%) met the criteria of sarcopenia. Subjects with a history of lung cancer, genitourinary cancer, or gastric cancer were prone to develop sarcopenia (31.6%, 26.3%, and 21.4%, respectively). Furthermore, sarcopenia was more prevalent among elderly (≥65 years; P < 0.001), those with a lower BMI level (<23 kg/m²; P < 0.001), heavy drinker (P = 0.012), or smoker (P < 0.001), and those with inadequate intakes of protein (P = 0.017) and vitamin A (P = 0.024). Multivariable logistic analyses revealed sarcopenia was significantly associated with male gender (odds ratio [OR], 68.14; 95% CI, 15.52–299.13), a BMI of <23 kg/m² (OR 35.93, 95% CI, 8.24–156.67), and inadequate protein intake (OR 3.07, 95% CI, 1.30–7.22); these factors are significant predictors of sarcopenia in Korean cancer survivors.     

Lung health among boilermakers in Edmonton,Alberta

Background Construction boilermakers may be exposed to a variety of substances, including asbestos and welding fumes. Past studies of boilermakers have shown increases in mortality from lung cancer and asbestosis and radiographic changes consistent with asbestos exposure. Methods Respiratory symptoms, lung function, and radiographic changes were compared for 102 actively employed boilermakers with 20 or more years of union membership and 100 telephone workers. Posteroanterior chest radiographs were evaluated by two experienced chest physicians, with a third arbitrating disagreed films. Union members were further categorized as boilermakers (n = 50) or welders (n = 52), based on longest service. Lung health was also compared with employment in a number of work sectors for time, and time-weighted exposure to dust and fumes. Results Boilermakers had more respiratory symptoms than telephone workers, but lung function did not differ. Radiographic changes were more common among the boilermakers (20% with any change, 8% circumscribed, and 9% diffuse pleural thickening). None of the boilermakers had small radiographic opacities. Several symptoms suggestive of bronchial responsiveness were associated with fume exposures in the gas and oil industry. Workers whose longest service was as a boilermaker demonstrated more symptoms than did welders. FEV₁, FEV₁/FVC, FEF_25–75, and FEF₅₀ were significantly lower among boilermakers compared with welders. Conclusion Health screening programs for these workers are warranted. Am. J. Ind. Med. 34:381–386, 1998. © 1998 Wiley-Liss, Inc.     

Cancer mortality and wood dust exposure among participants in the American Cancer Society Cancer Prevention Study-II (CPS-II)

In 1994, the International Agency for Research on Cancer (IARC) classified wood dust as a human carcinogen, based on very strong evidence of a carcinogenic risk of sino-nasal cancer. Excesses of other cancers, including lung and stomach, have been reported among persons employed in wood industries or occupationally exposed to wood dust, but not as consistently. We investigated such possible associations using the mortality experience of 362,823 men enrolled in the American Cancer Society's Cancer Prevention Study — II in 1982 and followed up for 6 years. Within this group, 45,399 men (12.5%) reported either employment in a wood-related occupation or exposure to wood dust or both. Among woodworkers, a small but significant excess risk was found for all causes of death (RR 1.17 (95% CI 1.11–1.24)) and for total malignancies (RR 1.17 (1.05–1.30)). Among men who reported exposure to wood dust, there was an elevated risk of total mortality (RR 1.07 (1.03–1.11)), total malignancies (RR 1.08 (1.01—1.15)), and lung cancer (RR 1.17 (1.04–1.31)). Among woodworkers, a significant trend (P = 0.02) of increasing risk of lung cancer with increasing duration of exposure was observed. An unexpected, significantly increased mortality from prostate cancer was observed in both wood-employed and wood-exposed, and a twofold increased risk of fatal brain cancer was seen among the former. Lung cancer mortality was especially high among woodworkers who also reported exposure to asbestos or formaldehyde, and it appears that exposure to these known carcinogens may partly explain the observed increased risks. Excess sino-nasal cancer was not observed, but the number of cases was small. Am. J. Ind. Med. 34:229–237, 1998. © 1998 Wiley-Liss, Inc.     

Mortality among taxi drivers in Rome: A cohort study

The mortality pattern of taxi drivers in Rome as possibly exposed mainly to gasoline engine exhausts was evaluated by means of a historical cohort study. A total of 2,311 male subjects registered as taxi drivers between 1950 and 1975 was followed from 1965 through 1988. The overall mortality was lower than expected on the basis of regional (Latium) reference rates (692 deaths, standardized mortality ratio [SMR] = 0.89, 95% confidence interval [CI] 0.82–0.96), whereas the number of recorded deaths for malignant neoplasms was about the expected (205 deaths, SMR = 0.99, 95% CI 0.86–1.13). Mortality from circulatory and respiratory diseases was lower than expected. Diabetes was significantly increased (42 deaths, SMR = 1.73, 95% CI = 1.25–2.34). An increased SMR appeared for respiratory cancer (SMR = 1.23, 95% CI = 0.98–1.50), mainly due to lung cancer (observed [O] = 76, SMR = 1.23, 95% CI = 0.97–1.54); two pleural cancers were also recorded. The excess of lung cancer deaths was present only among those enrolled in the most recent period (1965–1975) (45 deaths, SMR = 1.40, 95% CI = 1.02–1.87), especially among those of younger age (<65 years) (SMR = 1.86); there was no relation between lung cancer mortality and latency since first enrollment in the cooperatives or duration of membership. There are difficulties in interpreting the excess of lung cancer on the basis of occupational exposures; however, the increased risk observed among workers employed in more recent calendar periods may be due to heavier exposure in the last decades; further follow-up of the cohort may elucidate whether there is an increasing lung cancer risk among taxi drivers. © 1994 Wiley-Liss, Inc.     

High-resolution computed tomography in the early detection of asbestosis

Summary A group of 21 former asbestos sprayers was studied with high-resolution computed tomography (HRCT), and the findings were compared with radiographic, exposure and lung function variables. HRCT was superior to plain radiography in detecting parenchymal and pleural changes. It showed changes indicative of lung fibrosis, especially septal lines and parenchymal bands, in 9 of the 12 subjects (75%) with a plain radiographic category of 0/0 in the International Labour Office (ILO) 1980 classification of radiographs of pneumoconioses. The HRCT findings were classified according to a method developed by the authors, and an HRCT parenchymal score was calculated. The HRCT revealed pleural plaques in 19 of the 21 (90%) asbestos sprayers, whereas plain radiography detected pleural plaques in only 5 (24%) sprayers. Changes in the visceral pleura were detected twice as often with HRCT as with plain radiography. In the group without radiographic evidence of lung fibrosis (ILO < 1/0) and without evidence of emphysema in either the radiographs or the HRCT examination, there was a correlation between the HRCT parenchymal score and diffusion capacity (r = –0.64, P = 0.03) and total lung capacity (r = –0.61, P = 0.04). This finding indicates that parenchymal changes seen only with HRCT are of clinical importance. The study strongly suggests that for asbestos exposed workers with an ILO classification of < 1/0 and functional impairment, an HRCT examination should always be considered.     

Relationship of mortality, occupation, and pulmonary diffusing capacity to pleural thickening in the First National Health and Nutrition Examination Survey

We studied the relationship of pleural thickening consistent with asbestos exposure to mortality, career employment in asbestos-related jobs, and pulmonary diffusing capacity among participants in the first National Health and Nutrition Examination Survey. Three "B" readers examined chest X-rays to identify 59 individuals with such pleural abnormalities. From 1975 to 1984, the all-cause mortality rate ratio (RR) comparing males with and without occupational pleural thickening was 1.3 (95% C.I. 0.8-2.2). For lung cancer, the mortality RR for males was 3.0 (95% C.I. 1.0-9.1). Career asbestos work was not associated with occupational pleural thickening among men, probably because some with the condition had only short-term exposure to asbestos. Pulmonary diffusing capacity was lower in those with occupational pleural thickening, taking smoking into account. These results suggest that individuals in the general population who have occupational pleural thickening are at risk for some of the health consequences of asbestos work, including lung cancer, even if they were not career asbestos workers.     

Asbestos and kidney cancer: the evidence supports a causal association

The role of asbestos in the etiology of lung cancer and of mesothelioma of the pleura and peritoneum has been well documented. The evidence for a causal association between asbestos and other human cancers is not as extensive but suggests that asbestos may be carcinogenic at several different sites. This paper is concerned specifically with a possible causal association between asbestos and human kidney cancer. A review of the evidence to date indicates that only three human studies have sufficient statistical power to detect an excess mortality from kidney cancer among workers exposed to asbestos. All three were occupational cohort studies, and two of these gave strong direct evidence for such an excess; a study of U.S. insulators (kidney cancer SMR = 2.22, 90% CI 1.44-3.30), and a study of U.S. asbestos products company workers (kidney cancer SMR = 2.76, 90% CI 1.29-5.18). The third study, of Italian shipyard workers, reported excess mortality from "cancers of the kidney, urinary bladder, and other urinary organs" (SMR = 1.98, 90% CI 1.42-2.70). Further support for a causal association includes studies finding asbestos fibers in human kidneys and urine, as well as reports of kidney tumors in two animal bioassays. It is concluded that asbestos should be regarded as a probable cause of human kidney cancer.     

Malignant mesothelioma--German mesothelioma register 1987-1999

Objectives: The study group comprised a collective of 1,605 patients with malignant mesotheliomas and with lung tissue available for lung dust analyses. Method: Clinical features, occupational histories, expositions and individual data were evaluated, and the asbestos bodies concentrations (asbestos bodies/cm³ lung tissue or g wet tissue) were determined. Results: Mesotheliomas developed mainly in men (94.5%). Of the cases, 96.4% were of pleural origin and only 3.3% were peritoneal mesotheliomas. The biphasic subtype predominated (61.3%), followed by the epithelioid type (29.3%). The sarcomatoid subtype was rarely developed (9.4%). Mean age at first diagnosis was 60.4 years. The mean survival time from time of symptom onset was 13.5 months. Patients with epithelioid subtypes had a longer survival time (16.9 months) than those with biphasic (13.1 months) and sarcomatoid subtypes (5.5 months). Of the patients, 73% presented pleural effusions as initial symptoms of the disease. An increased asbestos burden was identified by light microscopy in 84.8% of the patients. There was no association between histological subtypes and the asbestos burden of the lungs. Patients with peritoneal mesotheliomas had distinctly higher asbestos burdens in the lungs than patients with pleural mesotheliomas. There exists no association between lung asbestos burdens and survival times. The mean latency period was 37.8 years. A trend: higher asbestos burden of the lung/shorter latency periods was suggested. About 70% of the patients had a history of occupational exposure to asbestos dust. Most patients worked in the building trade, the locksmith and machine building industries and in the steel and blast-furnace industries. Of the patients, 25.6% had asbestos-associated lung fibroses, in 40.7% of the cases pleural plaques were identified. Conclusions: The most important causal factor for development of mesotheliomas is still asbestos, primarily amphibole asbestos. The recurring occurrence of mesotheliomas in younger people without known asbestos exposure needs the urgent investigation of other inducing factors for mesotheliomas. Received: 11 September 2000 / Accepted: 20 February 2001     

Mortality due to asbestos-related causes among railway carriage construction and repair workers

The objective of this study was to further clarify the cancer risk associated with asbestos exposure in railway carriage construction and repair. The cohort included 734 subjects employed between 1 January 1945 and 31 December 1969. Vital status was ascertained at 31 December 1997. Mortality was investigated in the time span 1970-97. Forty-two subjects (6%) were lost to follow-up and eight causes of death (4%) could not be ascertained. The overall mortality was not above the expected value. Among neoplastic diseases, excesses were observed for lung ?tandardized mortality ratio (SMR) = 124; 90% confidence interval (CI) = 87-172; 26 obs), pleura (SMR = 1,327; CI = 523-2,790; 5 obs), larynx (SMR = 240; CI = 95-505; 5 obs), liver (SMR = 241; CI = 126-420; 9 obs), pancreas (SMR = 224; CI = 98-443; 6 obs) and multiple myeloma (SMR = 429; CI = 117-1,109; 3 obs). The observed excess of lung and pleural neoplasms can be causally related to asbestos exposure in the manufacture of railway carriages. A causal role of asbestos exposure in the raised SMRs from laryngeal and pancreatic neoplasms and multiple myeloma cannot be conclusively proven.