Relative risk of mesothelioma among railroad machinists exposed to chrysotile

This study challenges the assertion of low relative risk of chrysotile in the causation of mesothelioma. Data are provided on the time period use of various types of asbestos in the United States and in insulation materials. The focus of the study is on mesothelioma among railroad machinists employed in the steam locomotive era who were exposed to chrysotile. Within a cohort of machinists alive January 1, 1945, a sub-cohort method was applied to all successive machinists hired in each of the respective years (1920-1929) followed through 1986. The total cohort was 181 and the number of deaths 156, with 14 mesotheliomas identified among 41 cancer deaths. The findings demonstrated an extremely high relative risk for machinists exposed to chrysotile for the induction of mesothelioma in the individual year of hire cohorts. A similar observation was noted for other crafts hired in the same time period. One mesothelioma occurred for every 13 machinists hired in the succeeding years (1920-1929) and constituted 34% of all cancer deaths. It is concluded that chrysotile is far more hazardous in the induction of mesotheliomas and that the asbestos cancer risk in the steam locomotive eras was much higher than had been previously estimated.     

Malignant pleural mesothelioma among Swiss furniture workers. A new high-risk group

Within the framework of a research project concerning occupational mortality, attention was drawn to a highly significant standardized mortality ratio for mesothelioma among furniture workers. From information drawn from the mortality records for the years 1979-1985 and from the 1980 national census, the number of pleural mesotheliomas among this occupational group was examined. The expected number of deaths from pleural mesothelioma among Swiss furniture workers for this period was 4.4; the observed number was 12. This finding indicates a 2.7-fold relative risk (P = 0.004) for death due to these cancers among Swiss furniture workers.     

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.     

Current nitrogen dioxide exposures among railroad workers

As part of a series of epidemiologic studies of the mortality patterns of railroad workers, various air contaminants were measured to characterize the workers' current exposures to diesel exhaust. Nitrogen dioxide (NO2), which is a constituent of diesel exhaust, was examined as one possible marker of diesel exposure. An adaptation of the Palmes personal passive sampler was used to measure the NO2 exposures of 477 U.S. railroad workers at four railroads. The range of NO2 exposures expressed as the arithmetic average +/- two standard errors for the five career job groups were as follows: signal maintainers, 16-24 parts per billion (ppb); clerks/dispatchers/station agents, 23-43 ppb; engineers/firers, 26-38 ppb; brakers/conductors, 50-74 ppb; and locomotive shop workers, 95-127 ppb. Variations among railroads and across seasons were not significant for most job groups.     

Quantitative assessment of the risk of lung cancer and pleural mesothelioma among automobile mechanics

BACKGROUND: A quantitative assessment of the risk of lung cancer and pleural mesothelioma among mechanics exposed to dust released from automobile asbestos-containing parts was performed. METHODS: The population of automobile mechanics in France, according to profession and industrial sectors codes, was estimated from the data of the 1999 census. Risks were computed for a total male population of 242,360 automobile mechanics aged 16 to 60 years. Exposure to asbestos among these workers comes from maintenance tasks involving asbestos-containing parts produced before 1997 (date of the asbestos ban in France). Airborne asbestos concentration data available from the literature were highly variable. No data reporting the distribution of time spent for such tasks over a typical week of work were available. Therefore, different weekly exposure profiles were simulated, based on data from the 1994 SUMER survey. Risk models were those used for assessing asbestos health effects by all national and international agencies. Exposure scenarios mixed different levels of exposure, periods of time, proportions of exposed workers and dates of the "natural" disappearance of the automobile fleet built before asbestos was banned in brakes and other parts. The most realistic scenario hypothesizes that all automobile mechanics were exposed to asbestos, that the exposure levels ranged from 0.06 and 0.25 fibers/liter per week for the period before 1997, and between 0.01 and 0.06 fibers/liter per week afterwards until 2010. RESULTS: According to this scenario, the number of lifelong cancer deaths (lung and pleura) induced by asbestos exposure in this population is estimated at 602 "unavoidable" cases, due to exposure experienced before 2003; 43 other cases will occur if asbestos is not removed from existing automobiles.     

Unexpected categories at risk of S. aureus nasal carriage among hospital workers

ObjectivesThirty percent of the general population are Staphylococcus aureus nasal carriers. It has been shown that this increases with repeated contact with patients, but it is not known whether all categories of healthcare workers are at equal risk of carriage. We aimed to explore S. aureus nasal carriage among healthcare professionals.MethodsProspective study conducted in two French university hospitals in 2014 and 2016. Volunteers were screened for S. aureus nasal carriage. Profession and hygiene habits were collected. Based on the results of this initial study, a second study focused on semi-skilled workers and biomedical equipment technicians (BETs) only; participants were given education on the basic rules of hygiene, then re-screened three months later.ResultsIn the initial study, 38.8% of the 436 participants were detected as nasal carriers. There was a significant difference in nasal carriage according to professional category (p < 0.0001); the lowest was found among administrative agents (17.3%), followed by healthcare providers (37.4%), laboratory technicians (37.6%). The greatest proportion was found among semi-skilled workers and BETs (52.9%). Spa-typing ruled out the hypothesis of a single clone dissemination among colleagues. After the three-month hygiene awareness campaign, all re-screened individuals remained positive, and with their respective initial strain.ConclusionsTo the best of our knowledge we report here for the first time that semi-skilled workers and BETs are specifically more at risk of S. aureus nasal colonisation. This striking finding urges hospital hygiene departments to evaluate this specific professional category and implement strategies to improve hygiene awareness.     

Past exposure to asbestos among active railroad workers

Before the transition from steam- to diesel-powered locomotives during the 1950s certain railroad workers had the opportunity for significant occupational exposure to asbestos. Past studies have demonstrated that older workers with jobs associated with the repair of steam locomotives had the most exposure. To determine the prevalence of currently employed railroad workers with past asbestos exposure we surveyed 514 white male employees of an active US railroad by mail questionnaire. Twenty-one percent (50/242) of the workers 50 years old or greater had likely asbestos exposure compared to 3% (9/275) of the workers 49 years old or less (p less than .001). Fifteen (30%) of the 50 older workers with likely asbestos exposure had current job titles no longer suggestive of past exposure. The duration of exposure of these older active workers was short, (median = 3 years; range, 6 months to 15 years). A history of past asbestos exposure may still be obtained among active railroad workers with past railroad shop employment.     

High risk for nasal carriage of methicillin-resistant Staphylococcus aureus among Danish veterinary practitioners

OBJECTIVES: Due to their multiple antibiotic resistance properties, methicillin-resistant Staphylococcus aureus (MRSA) are a major public health problem. After the recently described emergence of MRSA in animals, the authors investigated the risk of nasal MRSA carriage among people with professional contact with animals. METHODS: Nasal swabs and information on animal exposure and known MRSA risk factors were obtained from participants (N=702) at five conferences organized by national veterinary and farmer associations and students at a business school in Denmark. All of the participants were screened by standard microbiological techniques for MRSA detection and characterization. RESULTS: MRSA carriage was significantly (P<0.02) higher among the veterinary practitioners (3.9%) than among the participants not professionally exposed to animals (0.7%). Six of the nine MRSA strains isolated from veterinary practitioners belonged to clonal complexes (CC) previously associated with horses (CC8), small animals (CC22), and pigs (CC398). Although four of the nine positive veterinarians carried the CC associated with pigs, exposure to small animals, cattle, or horses, but not to pigs, was found to be a significant risk factor. CONCLUSIONS: The results indicate that veterinarians are at risk of MRSA carriage. Veterinary professionals should be informed about this emerging occupational health risk and educated about preventive measures. Collaboration between national medical and veterinary institutions is urgently needed to control the spread of these unwanted bacteria in the community.     

The additional risk of malignant mesothelioma in former workers and residents of Wittenoom with benign pleural disease or asbestosis

Aims: To examine the hypothesis that people with benign pleural disease or asbestosis have an increased risk of malignant mesothelioma beyond that attributable to their degree of asbestos exposure. Methods: Former workers and residents of the crocidolite mining and milling town of Wittenoom are participating in a cancer prevention programme (n = 1988). The first plain chest radiograph taken at the time of recruitment into the cancer prevention programme was read for evidence of benign pleural disease and asbestosis, using the UICC classification. Crocidolite exposure of former workers was derived from employment records and records of dust measurements performed during the operation of the asbestos mine and mill between 1943 and 1966. Based on fibre counts, exposure for former residents was determined using duration of residence and period of residence (before and after a new mill was commissioned in 1957) and interpolation from periodic hygienic measures undertaken from personal monitors between 1966 and 1992. Cox proportional hazards modelling was used to relate benign pleural disease, asbestosis, asbestos exposure, and mesothelioma. Results: Between 1990 and 2002, there were 76 cases of mesothelioma (56 of the pleura and 20 of the peritoneum). Cases had more radiographic evidence of (all) benign pleural disease, pleural thickening, blunt/obliterated costophrenic angle, and asbestosis than non-cases. Adjusting for time since first exposure (log years), cumulative exposure (log f/ml-years), and age at the start of the programme, pleural thickening (OR = 3.1, 95% CI 1.2 to 7.6) and asbestosis (OR = 3.3, 95% CI 1.3 to 8.6) were associated with an increased risk of peritoneal mesothelioma. There was no increased risk for pleural mesothelioma. Conclusion: The presence of benign pleural disease, in particular pleural thickening, and asbestosis appears to increase the risk of mesothelioma of the peritoneum, but not of the pleura beyond that attributable to indices of asbestos exposure in this cohort of subjects exposed to crocidolite.     

Different measures of asbestos exposure in estimating risk of lung cancer and mesothelioma among construction workers

To analyze occupation, expert-evaluated cumulative exposure, and radiographic abnormalities as indicators of asbestos-related cancer risk we followed 16,696 male construction workers for cancer in 1990-2000. We calculated standardized incidence ratios (SIR) in comparison to the Finnish population and relative risks (RR) in a multivariate analysis in comparison to the internal low-exposure category of each indicator. Overall, the risk was increased for mesothelioma (SIR 2.0, 95% CI = 1.0-3.3), but not for lung cancer (SIR 1.1, 95% CI = 0.9-1.2). Radiographic lung fibrosis indicated a 2-fold and a high value of the exposure index a 3-fold RR of lung cancer, while there was no risk among those with pleural plaques. The risk of lung cancer was the highest in insulators (RR 3.7, 95% CI = 1.4-9.9). Occupation, expert-evaluated cumulative exposure, and lung fibrosis are useful indicators of lung cancer risk among construction workers.     

Mortality risk among elderly workers

We analyzed population-based data for respondents aged 70 and older from the Longitudinal Study on Aging. We compared mortality risk among 358 baseline-year working with 4,373 nonworking respondents. Including other demographic and health status predictors in a multiple logistic regression model, employment remained a significant predictor of survival (mortality odds ratio (OR) = 0.4). Diabetes mellitus was the only factor that displayed a mortality risk that was significantly interactive with work (OR = 3.5). These data suggest that a healthy worker effect persists in older age groups, but that within the working stratum, patterns of risk may differ as compared to those among the nonworking.     

饮食服务业人员沙门氏菌携情况调查及分析

目的：了解和分析武汉市桥口地区饮食服务从业人员沙门氏菌携带情况及菌型分布特点，耐药率，方法：按沙门氏菌分离鉴定方法进行检测，按WHO推荐的K－B法进行药敏试验。结果：从45353名饮食从业人员体检中，共检出7个血清群，34个血清型，558株沙门氏菌，检出率为1．23％，558株菌100％耐青霉素G、红霉素、万古霉素，对复方新诺明，妥布霉素、庆大霉素、先锋V、无锋必100％敏感，其次为诺氟沙星99．2％，丁胺卡那、头孢拉定97．5％，氧哌嗪青霉素95．13％，环丙沙星，卡那霉素92．7％，四环素85．37％，氨卞青霉素78．29％。结论：从事饮食服务行业人员在畜禽加工中易感染沙门氏菌成为腹泻病或健康带菌者，对所从事的饮食业存在着潜在的危险性，所检菌株对大部分物均敏感，卫生防商部门要加强卫生管理和监测，防止和控制食品的外源性污染。