| Ralls statement that countervailing human data on the carcinogenic effects of
chrysotile asbestos (including large numbers of mesotheliomas among Canadians)
exist is reminiscent of a similar claim by Nicholson et al. (7) in which his
exaggerated numbers were correctly put into perspective by the epidemiologists
studying the Canadian workers (8). His unreferenced conclusion that
mesotheliomas are largely from chrysotile exposure in insulation workers and
family members who were exposed to low doses ignores the fact that these
individuals encountered mixed exposures to chrysotile and amphiboles at much
higher concentrations than levels of asbestos (predominantly chrysotile)
occurring in homes and public buildings today. Moreover, Rall does not
acknowledge the significant content of amphibole fibers in the lungs of these
workers (9) as well as recent studies showing a correlation between the lung
burden of tremolite, but not chrysotile, in the lungs of Canadian miners with
mesothelioma (. |
| Dr. Finkelstein also cited five cases of mesothelioma among former
Holmes workers. Three of the five workers died at less than fifty years
of age and all were less than sixty years old! |
| The analysis of 335 cases of mesothelioma observed at the Ramazzini
Foundation and the Bologna Institute of Oncology has
shown: 1) a high percentage of correlation of these tumours with
asbestos exposure; 2) a large number of population categories
potentially exposed to asbestos fibres and therefore at risk of
developing mesothelioma; and 3) the high risk of mesothelioma
among people exposed in various circumstances to asbestos used in
railroads and sugar refinery plants.
______________________________________________________
Med Lav 1997 Jul-Aug;88(4):316-20 |
| Mr. Bichard finds it hard to contain his anger over his medical problems
and those of colleagues who are dead or are suffering from lung cancer,
brain tumours, or mesothelioma, a rare cancer of the lung lining. |
| All cases of pleural malignant mesothelioma occurring in Tuscany were
collected, backdated to 1980 (to 1970 for the
provinces of Florence and Prato; to 1975 for the provinces of Pisa
and Siena), in order to evaluate the incidence of
occupational exposure to asbestos. The aim was to enhance primary
prevention in those workplaces still at risk nowadays. To
achieve information on the possible occupational, domestic or
environmental exposure, an interview was conducted using a
semi-structured questionnaire. An exposure classification was
produced to focus preventive intervention. This surveillance
system needs to be developed to contribute to epidemiological
research, especially on the effects of low level exposures, and to
primary prevention.
_________________________________________________________
Med Lav 1997 Jul-Aug;88(4):302-9 |
