Historical state of knowledge of the health risks of asbestos posed to seamen on merchant ships.

We examined the development of knowledge concerning the risks posed by asbestos to seamen working aboard merchant ships at sea (i.e. commercial, rather than naval vessels). Seamen were potentially exposed to "in-place" asbestos on merchant ships by performing intermittent repair and maintenance tasks. We reviewed studies measuring airborne asbestos onboard merchant ships and health outcomes of merchant seamen, as well as studies, communications, and actions of U.S. organizations with roles in maritime health and safety. Up to the 1970s, most knowledge of the health risks of asbestos was derived from studies of workers in asbestos product manufacturing and asbestos mining and milling industries, and certain end-users of asbestos products (particularly insulators). We found that attention to the potential health risks of asbestos to merchant seamen began in the mid- to late 1970s and early 1980s. Findings of pleural abnormalities in U.S. seamen elicited some concern from governmental and industry/labor organizations, but airborne asbestos concentrations aboard merchant ships were found to be <1 f/cc for most short-term repair and maintenance tasks. Responses to this evolving information served to warn seamen and the merchant shipping industry and led to increased precautions regarding asbestos exposure. Starting in the 1990s, findings of modest increases in lung cancer and/or mesothelioma in some epidemiology studies of seamen led some authors to propose that a causal link between shipboard exposures and asbestos-related diseases existed. Limitations in these studies, however, together with mostly unremarkable measures of airborne asbestos on merchant ships, preclude definitive conclusions in this regard.

Cáncer de escroto: primera neoplasia profesional / Scrotal cancer: the first occupational cancer

No disponible

More evidence of unpublished industry studies of lead smelter/refinery workers.

BACKGROUND: Lead smelter/refinery workers in the US have had significant exposure to lead and are an important occupational group to study to understand the health effects of chronic lead exposure in adults. Recent research found evidence that studies of lead smelter/refinery workers have been conducted but not published. This paper presents further evidence for this contention. OBJECTIVES: To present further evidence of industry conducted, unpublished epidemiologic studies of lead smelter/refinery workers and health outcomes. METHODS: Historical research relying on primary sources such as internal industry documents and published studies. RESULTS: ASARCO smelter/refinery workers were studied in the early 1980s and found to have increased risk of lung cancer and stroke in one study, but not in another. CONCLUSIONS: Because occupational lead exposure is an on-going concern for US and overseas workers, all epidemiologic studies should be made available to evaluate and update occupational health and safety standards.

Analysis of workplace compliance measurements of asbestos by the U.S. Occupational Safety and Health Administration (1984-2011).

The United States Occupational Safety and Health Administration (OSHA) maintains the Chemical Exposure Health Data (CEHD) and the Integrated Management Information System (IMIS) databases, which contain quantitative and qualitative data resulting from compliance inspections conducted from 1984 to 2011. This analysis aimed to evaluate trends in workplace asbestos concentrations over time and across industries by combining the samples from these two databases. From 1984 to 2011, personal air samples ranged from 0.001 to 175 f/cc. Asbestos compliance sampling data associated with the construction, automotive repair, manufacturing, and chemical/petroleum/rubber industries included measurements in excess of 10 f/cc, and were above the permissible exposure limit from 2001 to 2011. The utility of combining the databases was limited by the completeness and accuracy of the data recorded. In this analysis, 40% of the data overlapped between the two databases. Other limitations included sampling bias associated with compliance sampling and errors occurring from user-entered data. A clear decreasing trend in both airborne fiber concentrations and the numbers of asbestos samples collected parallels historically decreasing trends in the consumption of asbestos, and declining mesothelioma incidence rates. Although air sampling data indicated that airborne fiber exposure potential was high (>10 f/cc for short and long-term samples) in some industries (e.g., construction, manufacturing), airborne concentrations have significantly declined over the past 30 years. Recommendations for improving the existing exposure OSHA databases are provided.

Historical occupational trichloroethylene air concentrations based on inspection measurements from Shanghai, China.

PURPOSE: Trichloroethylene (TCE) is a carcinogen that has been linked to kidney cancer and possibly other cancer sites including non-Hodgkin lymphoma. Its use in China has increased since the early 1990s with China's growing metal, electronic, and telecommunications industries. We examined historical occupational TCE air concentration patterns in a database of TCE inspection measurements collected in Shanghai, China to identify temporal trends and broad contrasts among occupations and industries. METHODS: Using a database of 932 short-term, area TCE air inspection measurements collected in Shanghai worksites from 1968 through 2000 (median year 1986), we developed mixed-effects models to evaluate job-, industry-, and time-specific TCE air concentrations. RESULTS: Models of TCE air concentrations from Shanghai work sites predicted that exposures decreased 5-10% per year between 1968 and 2000. Measurements collected near launderers and dry cleaners had the highest predicted geometric means (GM for 1986 = 150-190 mg m(-3)). The majority (53%) of the measurements were collected in metal treatment jobs. In a model restricted to measurements in metal treatment jobs, predicted GMs for 1986 varied 35-fold across industries, from 11 mg m(-3) in 'other metal products/repair' industries to 390 mg m(-3) in 'ships/aircrafts' industries. CONCLUSIONS: TCE workplace air concentrations appeared to have dropped over time in Shanghai, China between 1968 and 2000. Understanding differences in TCE concentrations across time, occupations, and industries may assist future epidemiologic studies in China.

Reconstruction of historical exposures at a Welsh nickel refinery (1953-2000).

Past epidemiological studies of workers in a nickel refinery in Clydach, Wales, have shown evidence of large excess respiratory cancer mortality risks [lung cancer relative risk (RR) ≈ 3; nasal cancer RR ≈ 140] in those employed prior to 1930, with risks dropping dramatically in workers hired subsequently. The pre-1930 risks have generally been attributed to high exposures to mixtures of nickel compounds. More recent studies of this refinery's workers have focused on those first hired in 1953, when many of the operations that presumably gave rise to the high exposures were no longer in operation. While these studies have shown greatly decreased lung cancer risks overall (RR ≈ 1.4), and no substantive evidence of increased nasal cancer risk, the absence of reliable exposure estimates have made it difficult to ascertain whether the increased lung cancer risks are nickel related or due to other factors. This study uses nickel measurements from the 1970s to the present, documentation of process changes, and dust measurements taken around the 1950s to construct an exposure matrix for the recent cohort. It provides evidence of at least 30-fold decreases in levels of nickel exposure from the 1950s to the present, with estimated inhalable nickel concentrations in the 1950s in excess of 5mg Ni m(-3).

[90th anniversary of national hygienic regulation of chemicals in workplace air].

The authors followed occurrence and formation of the national hygienic regulation of chemicals in workplace air, since 1920s in historical aspect. Now there is 90th anniversary of the regulation.

Estimating historic exposures at the European Gaseous Diffusion plants.

This paper describes the methods and results of an occupational exposure assessment covering 30 years of operation of the EURODIF establishment (1978-2008). The exposure assessment includes radiological, physical and chemical hazards, and takes into account of organizational changes at the establishment. Furthermore, it includes efforts to better quantify the levels of exposures using available industrial hygiene and health physics data. In total, 227 workers participated in the assessment of 26 different occupational exposures in 102 general workstations through 1978-2008. Only 7% of exposure levels were rectified by experts for internal consistency reasons. Noise, heat, trichloroethylene and soluble uranium compounds were the most prevalent exposures at the plant although their levels tended to decrease across time. Assessments of occupational exposure to noise based on JEM exposure levels were fairly well correlated with noise measurement data (Spearman's correlation coefficient, ρ=0.43) while JEM-based assessments of uranium exposure were not well correlated with uranium atmospheric measurements. This study demonstrates the importance of non-radiological exposure in the nuclear fuel industry and highlights the difficulties in managing the risks arising from these exposures. Occupational exposures remain difficult to quantify due to the scarcity of reliable monitoring data and the absence of binding occupational exposure limits for some of considered hazards.

Evaluation of historical beryllium abundance in soils, airborne particulates and facilities at Lawrence Livermore National Laboratory.

Beryllium has been historically machined, handled and stored in facilities at Lawrence Livermore National Laboratory (LLNL) since the 1950s. Additionally, outdoor testing of beryllium-containing components has been performed at LLNL's Site 300 facility. Beryllium levels in local soils and atmospheric particulates have been measured over three decades and are comparable to those found elsewhere in the natural environment. While localized areas of beryllium contamination have been identified, laboratory operations do not appear to have increased the concentration of beryllium in local air or water. Variation in airborne beryllium correlates to local weather patterns, PM10 levels, normal sources (such as resuspension of soil and emissions from coal power stations) but not to LLNL activities. Regional and national atmospheric beryllium levels have decreased since the implementation of the EPA's 1990 Clean-Air-Act. Multi-element analysis of local soil and air samples allowed for the determination of comparative ratios for beryllium with over 50 other metals to distinguish between natural beryllium and process-induced contamination. Ten comparative elemental markers (Al, Cs, Eu, Gd, La, Nd, Pr, Sm, Th and Tl) that were selected to ensure background variations in other metals did not collectively interfere with the determination of beryllium sources in work-place samples at LLNL. Multi-element analysis and comparative evaluation are recommended for all workplace and environmental samples suspected of beryllium contamination. The multi-element analyses of soils and surface dusts were helpful in differentiating between beryllium of environmental origin and beryllium from laboratory operations. Some surfaces can act as "sinks" for particulate matter, including carpet, which retains entrained insoluble material even after liquid based cleaning. At LLNL, most facility carpets had beryllium concentrations at or below the upper tolerance limit determined by sampling facilities with no history of beryllium work. Some facility carpets had beryllium concentrations above the upper tolerance limits but can be attributed to tracking of local soils, while other facilities showed process-induced contamination from adjacent operations. In selected cases, distinctions were made as to the source of beryllium in carpets. Guidance on the determination of facility beryllium sources is given.

Organic solvent use in enterprises in Japan.

This study was initiated to elucidate possible changes in types of organic solvents (to be called solvents in short) used in enterprises in Japan through comparison of current solvent types with historical data since 1983. To investigate current situation in solvent use in enterprises, surveys were conducted during one year of 2009 to 2010. In total, workroom air samples in 1,497 unit workplaces with solvent use were analyzed in accordance with regulatory requirements. Typical use pattern of solvents was as mixtures, accounting for >70% of cases. Adhesives spreading (followed by adhesion) was relatively common in small-scale enterprises, whereas printing and painting work was more common in middle-scale ones, and solvent use for testing and research purpose was basically in large-scaled enterprises. Through-out printing, painting, surface coating and adhesive application, toluene was most common (being detected in 49 to 82% of workplaces depending on work types), whereas isopropyl alcohol was most common (49%) in degreasing, cleaning and wiping workplaces. Other commonly used solvents were methyl alcohol, ethyl acetate and acetone (33 to 37%). Comparison with historical data in Japan and literature-retrieved data outside of Japan all agreed with the observation that toluene is the most commonly used solvent. Application of trichloroethylene and 1,1,1-trichloroethane, once common in 1980s, has ceased to exist in recent years.

Creating an integrated historical record of extreme particulate air pollution events in Australian cities from 1994 to 2007.

Epidemiological studies of exposure to vegetation fire smoke are often limited by the availability of accurate exposure data. This paper describes a systematic framework for retrospectively identifying the cause of air pollution events to facilitate a long, multicenter analysis of the public health effects of vegetation fire smoke pollution in Australia. Pollution events were statistically defined as any day at or above the 95th percentile of the 24-hr average concentration of particulate matter (PM). These were identified for six cities from three distinct ecoclimatic regions of Australia. The dates of each event were then crosschecked against a range of information sources, including online newspaper archives, government and research agency records, satellite imagery, and aerosol optical thickness measures to identify the cause for the excess particulate pollution. Pollution events occurred most frequently during summer for cities in subtropical and arid regions and during winter for cities in temperate regions. A cause for high PM on 67% of days examined in the city of Sydney was found, and 94% of these could be attributed to landscape fire smoke. Results were similar for cities in other subtropical and arid locations. Identification of the cause of pollution events was much lower in colder temperate regions where fire activity is less frequent. Bushfires were the most frequent cause of extreme pollution events in cities located in subtropical and arid regions of Australia. Although identification of pollution episodes was greatly improved by the use of multiple sources of information, satellite imagery was the most useful tool for identifying bushfire smoke pollution events.

The use of multizone models to estimate an airborne chemical contaminant generation and decay profile: occupational exposures of hairdressers to vinyl chloride in hairspray during the 1960s and 1970s.

Vinyl chloride (VC) was used as a propellant in a limited percentage of aerosol hairspray products in the United States from approximately 1967 to 1973. The question has arisen whether occupational exposures of hairdressers to VC-containing hairsprays in hair salons were sufficient to increase the risk for developing hepatic angiosarcoma (HAS). Transient two-zone and steady-state three-zone models were used to estimate the historical airborne concentration of VC for individual hairdressers using hairspray as well as estimated contributions from other hairdressers in the same salon. Concentrations of VC were modeled for small, medium, and large salons, as well as a representative home salon. Model inputs were determined using published literature, and variability in these inputs was also considered using Monte Carlo techniques. The 95th percentile for the daily time-weighted average exposure for small, medium, and large salons, assuming a market-share fraction of VC-containing hairspray use from the Monte Carlo analysis, was about 0.3 ppm, and for the home salon scenario was 0.1 ppm. The 95th percentile value for the cumulative lifetime exposure of the hairdressers was 2.8 ppm-years for the home salon scenario and 2.0 ppm-years for the small, medium, and large salon scenarios. If using the assumption that all hairsprays used in a salon contained VC, the 95th percentile of the theoretical lifetime cumulative dose was estimated to be 52-79 ppm-years. Estimated lifetime doses were all below the threshold dose for HAS of about 300 to 500 ppm-years reported in the published epidemiology literature.

State-of-the-science review: Does manganese exposure during welding pose a neurological risk?

Recent studies report that exposure to manganese (Mn), an essential component of welding electrodes and some steels, results in neurotoxicity and/or Parkinson's disease (PD) in welders. This "state-of-the-science" review presents a critical analysis of the published studies that were conducted on a variety of Mn-exposed occupational cohorts during the last 100 yr, as well as the regulatory history of Mn and welding fumes. Welders often perform a variety of different tasks with varying degrees of duration and ventilation, and hence, to accurately assess Mn exposures that occurred in occupational settings, some specific information on the historical work patterns of welders is desirable. This review includes a discussion of the types of exposures that occur during the welding process--for which limited information relating airborne Mn levels with specific welding activities exists--and the human health studies evaluating neurological effects in welders and other Mn-exposed cohorts, including miners, millers, and battery workers. Findings and implications of studies specifically conducted to evaluate neurobehavioral effects and the prevalence of PD in welders are also discussed. Existing exposure data indicate that, in general, Mn exposures in welders are less than those associated with the reports of clinical neurotoxicity (e.g., "manganism") in miners and smelter workers. It was also found that although manganism was observed in highly exposed workers, the scant exposure-response data available for welders do not support a conclusion that welding is associated with clinical neurotoxicity. The available data might support the development of reasonable "worst-case" exposure estimates for most welding activities, and suggest that exposure simulation studies would significantly refine such estimates. Our review ends with a discussion of the data gaps and areas for future research.

Airborne concentrations of benzene associated with the historical use of some formulations of liquid wrench.

The current study characterizes potential inhalation exposures to benzene associated with the historical use of some formulations of Liquid Wrench under specific test conditions. This product is a multiuse penetrant and lubricant commonly used in a variety of consumer and industrial settings. The study entailed the remanufacturing of several product formulations to have similar physical and chemical properties to most nonaerosol Liquid Wrench formulations between 1960 and 1978. The airborne concentrations of benzene and other constituents during the simulated application of these products were measured under a range of conditions. Nearly 200 breathing zone and area bystander air samples were collected during 11 different product use scenarios. Depending on the tests performed, average airborne concentrations of benzene ranged from approximately 0.2-9.9 mg/m(3) (0.08-3.8 ppm) for the 15-min personal samples; 0.1-8 mg/m(3) (0.04-3 ppm) for the 1-hr personal samples; and 0.1-5.1 mg/m(3) (0.04-2 ppm) for the 1-hr area samples. The 1-hr personal samples encompassed two 15-min product applications and two 15-min periods of standing within 5 to 10 feet of the work area. The measured airborne concentrations of benzene varied significantly based on the benzene content of the formulation tested (1%, 3%, 14%, or 30% v/v benzene) and the indoor air exchange rate but did not vary much with the base formulation of the product or the two quantities of Liquid Wrench used. The airborne concentrations of five other volatile chemicals (ethylbenzene, toluene, total xylenes, cyclohexane, and hexane) were also measured, and the results were consistent with the volatility and concentrations of these chemicals in the product tested. A linear regression analysis of air concentration compared with the chemical mole fraction in the solution and air exchange rate provided a relatively good fit to the data. The results of this study should be useful for evaluating potential inhalation exposures to benzene and other volatile chemicals that occurred during the past use of some formulations of Liquid Wrench and perhaps for some similar products containing these chemicals.

Cumulative asbestos exposure for US automobile mechanics involved in brake repair (circa 1950s-2000).

We analyzed cumulative lifetime exposure to chrysotile asbestos experienced by brake mechanics in the US during the period 1950-2000. Using Monte Carlo methods, cumulative exposures were calculated using the distribution of 8-h time-weighted average exposure concentrations for brake mechanics and the distribution of job tenure data for automobile mechanics. The median estimated cumulative exposures for these mechanics, as predicted by three probabilistic models, ranged from 0.16 to 0.41 fibers per cubic centimeter (f/cm(3)) year for facilities with no dust-control procedures (1970s), and from 0.010 to 0.012 f/cm(3) year for those employing engineering controls (1980s). Upper-bound (95%) estimates for the 1970s and 1980s were 1.96 to 2.79 and 0.07-0.10 f/cm(3) year, respectively. These estimates for US brake mechanics are consistent with, but generally slightly lower than, those reported for European mechanics. The values are all substantially lower than the cumulative exposure of 4.5 f/cm(3) year associated with occupational exposure to 0.1 f/cm(3) of asbestos for 45 years that is currently permitted under the current occupational exposure limits in the US. Cumulative exposures were usually about 100- to 1,000-fold less than those of other occupational groups with asbestos exposure for similar time periods. The cumulative lifetime exposure estimates presented here, combined with the negative epidemiology data for brake mechanics, could be used to refine the risk assessments for chrysotile-exposed populations.

Exposure-response analysis for beryllium sensitization and chronic beryllium disease among workers in a beryllium metal machining plant.

The current occupational exposure limit (OEL) for beryllium has been in place for more than 50 years and was believed to be protective against chronic beryllium disease (CBD) until studies in the 1990s identified beryllium sensitization (BeS) and subclinical CBD in the absence of physical symptoms. Inconsistent sampling and exposure assessment methodologies have often prevented the characterization of a clear exposure-response relationship for BeS and CBD. Industrial hygiene (3831 personal lapel and 616 general area samples) and health surveillance data from a beryllium machining facility provided an opportunity to reconstruct worker exposures prior to the ascertainment of BeS or the diagnosis of CBD. Airborne beryllium concentrations for different job titles were evaluated, historical trends of beryllium levels were compared for pre- and postengineering control measures, and mean and upper bound exposure estimates were developed for workers identified as beryllium sensitized or diagnosed with subclinical or clinical CBD. Five approaches were used to reconstruct historical exposures of each worker: industrial hygiene data were pooled by year, job title, era of engineering controls, and the complete work history (lifetime weighted average) prior to diagnosis. Results showed that exposure metrics based on shorter averaging times (i.e., year vs. complete work history) better represented the upper bound worker exposures that could have contributed to the development of BeS or CBD. Results showed that beryllium-sensitized and CBD workers were exposed to beryllium concentrations greater than 0.2 microg/m3 (95th percentile), and 90% were exposed to concentrations greater than 0.4 microg/m3 (95th percentile) within a given year of their work history. Based on this analysis, BeS and CBD generally occurred as a result of exposures greater than 0.4 microg/m3 and maintaining exposures below 0.2 microg/m3 95% of the time may prevent BeS and CBD in the workplace.

Task- and time-dependent weighting factors in a retrospective exposure assessment of chemical laboratory workers.

A chemical exposure assessment was conducted for a cohort mortality study of 6157 chemical laboratory workers employed between 1943 and 1998 at four Department of Energy sites in Oak Ridge, Tennessee, and Aiken, South Carolina. Previous studies of chemical laboratory workers have included members within professional societies where exposure assessment was either limited or not feasible, or chemical processing employees where laboratory and production workers were combined. Because sufficient industrial hygiene records were unavailable for all four sites, weighted duration of employment was used as a surrogate for the magnitude of exposure. Potential exposure indices were calculated for each worker using number of days employed and weighting factors for frequency of contact and year of employment. A total of 591 unique laboratory job titles indicative of a chemical laboratory worker were collapsed into 18 general job title categories. Through discussions with current and retired workers, along with examination of historical organizational charts and job descriptions, the percentage of time with activities involving the direct handling of chemicals in the laboratory was estimated for each job title category. Scaled weighting factors of 1, 0.6, 0.3, and 0.05 were assigned to the job title categories representing 100%, 60%, 30%, and 5% of daily activities handling chemicals, respectively. Based on limited industrial hygiene monitoring data, personal radiation monitoring records, and professional judgment, weighting factors that declined 4% annually were applied to each year to account for improvements in laboratory technique, advancements in instrumentation, improvement in engineering controls, and increased safety awareness through time. The study cohort was separated into three categories of chemical exposures based on department level information: (1) inorganic, (2) mixed inorganic and organic, and (3) unknown. Potential exposure indices ranged from 0.15 to 6824.5 with a median value of 377.5 and a mean equal to 884.2. This exposure assessment method is useful for epidemiologic analyses when quantitative exposure data are absent or insufficient.

Revising the British Occupational Hygiene Society asbestos standard: 1968-1982.

BACKGROUND: In 1968 the British Occupational Hygiene Society (BOHS) published a chrysotile asbestos hygiene standard. As a consequence of acknowledged inadequacies of the data, it underestimated the risks of exposure, but its influence was international and operated for longer than it merited. Five years later, BOHS reported the standard not to be in need of amending, despite its own doubts and no cognizance having been taken of the cancer hazard. Within months, stung by criticism from Dr. Irving J. Selikoff, industry required it to review the standard, which BOHS continued to do for a number of years before giving up. METHODS: Material obtained for the American Courts by means of legal discovery from an asbestos company's archive, provided information on the membership of the new BOHS committees, and on its operation. RESULTS: Alterations in the composition of the new committees included importantly the introduction of certain independent scientists, whose rigor militated against the ready production of a new hygiene standard acceptable to industry. CONCLUSIONS: There was a time in Britain when a learned society might with impunity omit to consult the views of workers or their representatives when making value judgments about their health and safety, but consider it proper to accede to industry's decision as to what hygiene standard it would accept. Health and Safety at Work legislation in 1974, established an organization on which industry and labor were represented, with the onus for recommending hygiene standards. For several years the BOHS Asbestos Sub-Committee continued attempting to reconcile the interests of industry, until finally abandoning hygiene standard setting as its mission.

SPATTER! SPATTER! SPATTER! Workers' health and the spray machine debate.

A conflict between industrialization and worker health developed in the painting industry during the early 1900s with the introduction of the spray machine. This technological innovation allowed the application of paint at greater speed and lower cost than hand painting and increased the rate at which painters were exposed to lead and other toxins contained in paint. From roughly 1919 to 1931, the painters' trade union clashed with employers, paint manufacturers, and legislatures over the impact of the spray machine on the health of workers and the need to enact legislation to regulate its use. While painters made gains on local, state, and national levels during the 1920s to prevent the use of the spray machine, their efforts ultimately failed.