1672 mensen die tussen 1935 en 1981 met het met asbest vervuild vermiculiet uit het Amerikaanse Libby (Montana) hadden gewerkt hebben vaker dan gemiddeld longkanker, asbestose en mesothelioom. Het risico op longkanker en asbestose hangt samen met de mate van blootstelling. Maar ook mensen die korter dan een jaar met het materiaal hebben gewerkt lopen een hoger dan gemiddeld risico op één van deze ziektes. Bron: Sullivan, P.A. (2007).Vermiculite, Respiratory Disease, and Asbestos Exposure in Libby, Montana: Update of a Cohort Mortality Study. Environmental Health Perspectives 115:579-585.
Sullivan, P.A. (2007).Vermiculite, Respiratory Disease, and Asbestos Exposure in Libby, Montana: Update of a Cohort Mortality Study. Environmental Health Perspectives 115:579-585.

ABSTRACT

BACKGROUND: Vermiculite from the mine near Libby, Montana, is contaminated with tremolite asbestos and other amphibole fibers (winchite and richterite). Asbestos-contaminated Libby vermiculite was used in loose-fill attic insulation that remains in millions of homes in the United States, Canada, and other countries.

OBJECTIVE: This report describes asbestos-related occupational respiratory disease mortality among workers who mined, milled, and processed the Libby vermiculite.

METHODS: This historical cohort mortality study uses life table analysis methods to compare the age-adjusted mortality experience through 2001 of 1,672 Libby workers to that of white men in the

U.S. population.

RESULTS: Libby workers were significantly more likely to die from asbestosis [standardized mortality ratio (SMR) = 165.8. 95% confidence interval (CI), 103.9-251.1], lung cancer (SMR = 1.7. 95% CI, 1.4-2.1), cancer of the pleura (SMR = 23.3. 95% CI, 6.3-59.5), and mesothelioma. Mortality from asbestosis and lung cancer increased with increasing duration and cumulative exposure to airborne tremolite asbestos and other amphibole fibers.

CONCLUSIONS: The observed dose-related increases in asbestosis and lung cancer mortality highlight the need for better understanding and control of exposures that may occur when homeowners or construction workers (including plumbers, cable installers, electricians, telephone repair personnel, and insulators) disturb loose-fill attic insulation made with asbestos-contaminated vermiculite from Libby, Montana.