Vermiculite Worker Mortality: Estimated Effects of Occupational Exposure to Libby Amphibole

  title={Vermiculite Worker Mortality: Estimated Effects of Occupational Exposure to Libby Amphibole},
  author={Theodore Larson and Vinicius C Antao and Frank James Bov{\'e}},
  journal={Journal of Occupational and Environmental Medicine},
Objective: To examine the relationship between cumulative fiber exposure (CFE) and mortality in a retrospective cohort study of vermiculite workers exposed to Libby amphibole (n = 1862). Methods: Extended Cox regression was used to estimate the hazards associated with CFE as a time-dependent covariate of multiple-cause mortality. Results: The Cox models for mesothelioma, asbestosis, lung cancer, and non-malignant respiratory disease were significant with rate ratios that increased monotonically… 

Mesothelioma Associated With Commercial Use of Vermiculite Containing Libby Amphibole

Workers expanding and processing Libby vermiculite in a manufacturing setting demonstrated an increased risk for the development of mesothelioma following exposure to the amphibole fiber contained within this verMiculite ore source.

Mortality from asbestos-associated disease in Libby, Montana 1979–2011

The results suggest that the general population may be experiencing asbestos-related effects, not just former vermiculite workers, and additional research is needed to determine whether SMRs remain elevated after controlling for secondary exposure, such as living with vermicULite workers.


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Comparisons of health outcomes in mice exposed to either LAA or the fibrous amphiboles collected in Arizona at the Lake Mead National Recreational Area at very low doses suggest there is risk of pulmonary disease and autoimmune outcomes with environmental exposure to amphibole asbestos, and that this is not limited to Libby, Montana.

Multiple pathway asbestos exposure assessment for a Superfund community

A comprehensive exposure assessment approach is developed that integrates information on individuals’ contact frequency with multiple exposure pathways and will advance health studies and risk assessment approaches in this population with a complex history of both occupational and environmental asbestos exposure.

Comparative health effects in mice of Libby amphibole asbestos and a fibrous amphibole from Arizona

Vascular and Thrombogenic Effects of Pulmonary Exposure to Libby Amphibole

Exposure to Libby amphibole (LA) asbestos decreased circulating platelets and platelet coagulability while increasing the expression of oxidative stress, thrombosis, and vasoconstriction biomarkers in the aorta of healthy rats, suggestingThrombogenic, vasocontractile, and oxidative stress-mediated impairments.

Sumas Mountain chrysotile induces greater lung fibrosis in Fischer344 rats than Libby amphibole, El Dorado tremolite, and Ontario ferroactinolite.

It is demonstrated that fiber length and higher AR are directly correlated with the severity of fibrosis and that, in the rat, exposure to SM is more fibrogenic than LA which suggests that there may be cause for concern for people at risk of being exposed to NOA from the Sumas Mountain landslide.

Italian pool of asbestos workers cohorts: mortality trends of asbestos-related neoplasms after long time since first exposure

Pleural cancer rate increased during the first 40 years of TSFE and reached a plateau after and was confirmed for cancer of the lung, ovary, pleura and peritoneum but not of the larynx and the digestive tract.



Cohort study of mortality of vermiculite miners exposed to tremolite.

The results of this and case-referent analyses indicate an increased risk of mortality from respiratory cancer in this cohort of about 1% for each fibre year of exposure and in relation to estimated exposure the mortality experienced by the cohort from both lung cancer and mesothelial tumours was higher than in chrysotile mining.

Lung cancer mortality and fibre exposures among North Carolina asbestos textile workers

This study provides further evidence that exposure to chrysotile asbestos in textile manufacturing is associated with increased risk of lung cancer, asbestosis cancer of the pleura and mesothelioma.

The morbidity and mortality of vermiculite miners and millers exposed to tremolite-actinolite: Part II. Mortality.

Results indicated that mortality from nonmalignant respiratory disease (NMRD) and lung cancer was significantly increased compared to the U.S. white male population.

Lung cancer among industrial sand workers exposed to crystalline silica.

Examination of lung cancer mortality among industrial sand workers suggested that smoking might account for 10--20% of the lung cancer excess, but data lend support to the labeling by the International Agency for Research on Cancer of silica as a human carcinogen.

Radiographic abnormalities and exposure to asbestos-contaminated vermiculite in the community of Libby, Montana, USA.

The purpose of this analysis was to identify and quantify asbestos-related radiographic abnormalities among persons exposed to vermiculite in Libby and to examine associations between these outcomes and participants' self-reported exposures.

Fatal asbestosis 50 years after brief high intensity exposure in a vermiculite expansion plant.

The case of a 65-year-old accountant whose only asbestos exposure was during a summer job 50 years earlier in a California vermiculite expansion plant, who developed extensive fibrocalcific pleural plaques and end-stage pulmonary fibrosis, with rapidly progressive respiratory failure.

The morbidity and mortality of vermiculite miners and millers exposed to tremolite-actinolite: Part I. Exposure estimates.

The vermiculite ore and concentrate of a mine and mill near Libby, Montana, was found to be contaminated with fibrous tremolite-actinolite, and all 8-hr TWA job exposure estimates decreased from 1972-1976, and from 1977-1982 were less than 1 fiber/cc.

Ischemic heart disease mortality among miners and other potentially silica-exposed workers.

The results indicate a possible relation between silica-dust exposure and ischemic heart disease among miners and industrial sand workers and suggest shift work might explain some of the increased risk.

Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution.

Fine particulate and sulfur oxide--related pollution were associated with all-cause, lung cancer, and cardiopulmonary mortality and long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopULmonary and lung cancer mortality.

Amphibole asbestos from Libby, Montana: Aspects of nomenclature

Abstract Richterite-asbestos and winchite-asbestos are not listed in the federal regulations governing asbestos. However, asbestiform winchite is found in the gangue at the Libby, Montana,