Collegium Ramazzini call for an international ban on asbestos

Asbestos Products, Hazards, and Regulation

Asbestos is present in the United States in a multitude of products used in past decades, and in some products that continue to be imported and domestically produced. We have limited information on the hazards posed by some of these individual products and no information at all on most of them. Legal discovery of corporate documents has shed some light on the use of asbestos in some products and exposures from asbestos in others, sometimes adding considerably to what was in the published literature. But liability concerns have motivated corporate efforts to curtail governmental public health guidance on long-recognized hazards to workers. Liability considerations have also evidently led, in the case of asbestos brake linings, to the support of publication in the scientific literature of review articles denying in the 21st century what had been widely accepted and established in health policy in the 20th century. This report is an effort to illustrate the suppression and emergence of scientific knowledge in a climate of regulation and liability. Examples discussed are vinyl-asbestos flooring, feminine hygiene products, automotive friction materials, and asbestos contamination of other minerals such as talc and vermiculite. Global efforts to deal with the hazards of continuing marketing of asbestos products are also discussed.

Asbestos Exposure Causes Mesothelioma, But Not This Asbestos Exposure: An Amicus Brief to the Michigan Supreme Court

Manufacturers of asbestos brakes, supported by many manufacturing and insurance industry amicus curie, requested the Michigan Supreme Court to dismiss testimony of an expert regarding the ability of asbestos dust from brakes to cause mesothelioma as "junk science". Scientists are concerned with the sweeping and unequivocal claims that any conclusion that asbestos from brakes caused a signature asbestos-related disease in a particular person must be "junk science". The manufacturers' sweeping pronouncements are what veer from accepted, reliable mainstream scientific methods and conclusions. This article outlines the evidence supporting the conclusion that asbestos from brakes can and does cause mesothelioma, and describes the defendants' attempts to fabricate doubt about this conclusion.

Mesothelioma from chrysotile asbestos: update

PURPOSE

There are different mineral classes of asbestos, including serpentines and amphiboles. Chrysotile is the main type of serpentine and by far the most frequently used type of asbestos (about 95% of world production and use). There has been continuing controversy over the capability of chrysotile asbestos to cause pleural and peritoneal mesothelioma. This review is to help clarify the issue by detailing cases and epidemiology studies worldwide where chrysotile is the exclusive or overwhelming fiber exposure.

METHODS

A worldwide literature review was conducted of asbestos and associated mesothelioma including case series, case-control and cohort epidemiology studies searching for well documented chrysotile asbestos associated mesothelioma cases.

RESULTS

Chrysotile asbestos exposures have occurred in many countries around the world from mining, manufacturing and community exposures. There have been many documented cases of mesothelioma from those exposures.

CONCLUSIONS

Chrysotile asbestos, along with all other types of asbestos, has caused mesothelioma and a world-wide ban of all asbestos is warranted to stop an epidemic of mesothelioma.

Pleural plaque related to asbestos mining in Taiwan

A 78-year-old woman complained of twisting-like pain in her left lower chest. During physical examination, friction rubbing was noted in both lungs. Chest radiography showed extensive bilateral pleural calcification. High-resolution computed tomography confirmed the presence of bilateral calcified pleural plaques. The patient had worked at a Japanese asbestos factory in Taiwan for 1 year when she was 16 years old. Her job involved picking out asbestos fibers from crushed asbestos minerals, but no protective equipment was used at that time. This is believed to be the first reported case of asbestos-related disease in Taiwan that resulted from asbestos mining. We also summarize the history of domestic asbestos mining, importation of asbestos, and trends in asbestos use in Taiwan.

Asbestosis mortality surveillance in the United States, 1970-2004

To describe the demographic, geographic, and occupational distribution of asbestosis mortality in the United States during 1970-2004, we identified a total of 25,413 asbestosis deaths. We calculated national, state, and county death rates, age-adjusted to the 2000 U.S. standard population. We also calculated industry- and occupation-specific proportionate mortality ratios (PMRs), adjusted for age, sex, and race, and corresponding confidence intervals (CIs) using available data. The overall U.S. age-adjusted asbestosis death rate was 4.1 per million population per year; the rate for males (10.4) was nearly 35-fold higher than that for females (0.3). It increased significantly from 0.6 to 6.9 per million population from 1970 to 2000 (p<0.001), and then declined to 6.3 in 2004 (p=0.014). High asbestosis death rates occurred predominantly, though not exclusively, in coastal areas. Industries with highest PMRs included ship and boat building and repairing (18.5; 95% CI 16.3-20.9) and miscellaneous nonmetallic mineral and stone products (15.9; 95% CI 13.0-19.5). Occupations with highest PMRs included insulation workers (109.2; 95% CI 93.8-127.2) and boilermakers (21.3; 95% CI 17.0-26.6).

Canada's asbestos legacy at home and abroad

Despite international efforts to block Canada's export of asbestos, the Canadian federal government continues to defend the economic interests of the asbestos industry. Ironically, Canadian asbestos miners, mill workers, and those engaged in a wide range of other occupations continue to suffer asbestos-related disease and premature death. Although there is an employer-funded compensation system in each province, many workers with mesothelioma and other asbestos-related diseases remain uncompensated. The export of Canadian asbestos to developing countries sets the stage for another preventable occupational disease epidemic that will manifest over the coming decades. There is growing support from the Canadian labor movement for an end to asbestos exportation and for a just transition strategy for the asbestos workers and their communities.

A Biomimetic Approach to the Chemical Inactivation of Chrysotile Fibres by Lichen Metabolites

Some lichens were recently reported to modify the surface state of asbestos. Here we report some new insight on the physico-chemical modifications induced by natural chelators (lichen metabolites) on two asbestos samples collected in two different locations. A biomimetic approach was followed by reproducing in the laboratory the weathering effect of lichen metabolites. Norstictic, pulvinic and oxalic acid (0.005, 0.5 and 50 mM) were put in contact with chrysotile fibres, either in pure form (A) or intergrown with balangeroite, an iron-rich asbestiform phase (B). Mg and Si removal, measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), reveals an incongruent dissolution for pure chrysotile (A), with Mg removal always exceeding that of Si, while chrysotile-balangeroite (B) follows a congruent dissolution pattern in all cases except in the presence of 50 mM oxalic acid. A much larger removal of Mg than Si in the solutions of 0.5 and 50 mM oxalic acid with chrysotile (A) suggests a structural collapse, which in the case of chrysotile-balangeroite (B) only occurs with 50 mM oxalic acid; in these cases both samples are converted into amorphous silica (as detected by X-ray diffraction (XRD)). Subsequent to incubation, some new phases (Fe(2)O(3), CaMg(CO(3))(2), Ca(C(2)O(4)) x H(2)O and Mg(C(2)O(4))2 x H(2)O), similar to those observed in the field, were detected by XRD and micro-Raman spectroscopy. The leaching effect of lichen metabolites also modifies the Fenton activity, a process widely correlated with asbestos pathogenicity: pure chrysotile (A) activity is reduced by 50 mM oxalic acid, while all lichen metabolites reduce the activity of chrysotile-balangeroite (B). The selective removal of poorly coordinated, highly reactive iron ions, evidenced by NO adsorption, accounts for the loss in Fenton activity. Such fibres were chemically close to the ones observed in the field. Chrysotile-rich rocks, colonised by lichens, could be exposed to a natural bioattenuation and considered as a transient environmental hazard.

Occupational asbestos exposure and predictable asbestos-related diseases in India

BACKGROUND

India imports nearly 100,000 metric tons of asbestos per year, and small-scale asbestos (chrysotile and tremolite) mining and milling contributes nearly 5%-10% of the total national usage. The industry is relatively young, having started in the 1950s and 1960s.

METHODS

Surveys of asbestos-exposed workers have identified significant occupational exposures, early pleural and parenchymal changes on chest radiograph, and decrements in lung function.

RESULTS AND CONCLUSIONS

Based on knowledge of past and current exposures to asbestos in industry, we can predict a future occurrence of clinical asbestos-related diseases-pleural changes, pulmonary fibrosis, bronchogenic carcinoma, and diffuse malignant mesothelioma. These cases of asbestos related disease are expected to occur in asbestos exposed workers from mining, milling, and manufacturing as well as in those with secondary exposures to asbestos-containing materials, including construction and maintenance workers, users of asbestos-containing consumer products, and the occupants of asbestos-containing buildings.