Chrysotile is a Proven Carcinogen
There is a health epidemic that has been known for many decades and it involves exposure to hazardous asbestos. One interesting study is called,“The Hazards of Chrysotile Asbestos:A Critical Review”by Philip J. Landrigan,William J. Nicholson,Yasunosuke Suzuki and Joseph Ladou –INDUSTRIAL HEALTH –Vol.37 ,No.3(1999)pp.271-280. Here is an excerpt:“Abstract:Chrysotile,or “white”,asbestos is the dominant form of asbestos in international commerce today. It accounts for 99% of current world asbestos production of 2 million tonnes. Chrysotile is an extremely hazardous material. Clinical and epidemiologic studies have established incontrovertibly that chrysotile causes cancer of the lung,Malignant Mesothelioma of the pleura and peritoneum,cancer of the larynx and certain gastrointestinal cancers. Chrysotile also causes asbestosis,a progressive fibrous disease of the lungs. Risk of these diseases increases with cumulative lifetime exposure to chrysotile and rises also with increasing time interval (latency) since first exposure. Comparative analyses have established that chrysotile is 2 to 4 times less potent than crocidolite asbestos in its ability to cause malignant mesothelioma,but of equal potency of causation of lung cancer. The International Agency for Research on Cancer of the World Health Organization has declared chrysotile asbestos a proven human carcinogen. Sales of chrysotile asbestos have virtually ended in Western Europe and North America,because of widespread recognition of its health hazards. However,asbestos sales remain strong in Japan,across Asia and in developing nations worldwide. The claim has been made that chrysotile asbestos can be used “safely”under “certain conditions”in those nations. That claim is not accurate. The Collegium Ramazzini,an international learned society in environmental and occupational medicine,has called for an immediate worldwide ban on all sales and uses of all forms of asbestos,including chrysotile. The rationale for this ban is threefold:(1) that safer substitute materials are readily available,(2) that “controlled”use of asbestos is not possible,and (3) that the health risks of asbestos are not acceptable in either the industrialized or the newly industrializing nations.”
Another interesting study is called,“Respiratory Cancer Incidence in Swedish Construction Workers Exposed to Man-Made Mineral Fibres and Asbestos”by
G. Engholm,A. Englund,A. C. Fletcher and N. Hallin. –Ann. occup. Hyg.,Vol. 31,No. 4B,pp. 663-675,1987. Here is an excerpt:“The incidence of respiratory cancer has been studied in relation to exposure to man-made mineral fibres (MMMF) within a large cohort of Swedish construction workers. The cohort comprised some 135 000 men,who were all examined by Bygghälsan at regular health check-ups in 1971–1974. The cohort has been followed for mortality through 1983 and for cancer incidence through 1982 by linkage to various national registries. A case-control study within the cohort has been carried out on 518 cases diagnosed as having respiratory cancer. For each case,five controls were selected among those who had not developed such a cancer with individual matching for age and year of first check-up. Subjects selected have been classified into categories based on self-reported exposure and on estimates of average intensity of exposure in occupations concerned. In the analysis smoking habits and density of population in parish of residence were included as potential confounders. Results of an analysis of the incidence of Pleural Mesothelioma in relation to exposure indicates that subjects in the cohort to some extent are unaware of their exposure to asbestos. The strong association between asbestos exposure and MMMF exposure makes it difficult to separate effects of the two exposures. The results,however,appear compatible with the known effect of asbestos exposure on lung cancer incidence. Subjects classified as heavily exposed to MMMF do not have a significantly higher incidence than unexposed subjects.”
Another interesting study is called,“Investigating Possible Effects of Asbestos in City Water:Surveillance of Gastrointestinal Cancer Incidence In Duluth,Minnesota”by
Barry S Levy,Eunice Sigurdson,Jack Mandel,Emaline Laudon and John Pearson –
American Journal of Epidemiology Vol. 103,No. 4:362-368. Here is an excerpt:“
The recent discovery of over one million asbestos-like fibers per liter of Duluth tap water and the suggestive evidence of a link between certain gastrointestinal (GI) cancers and work exposure to asbestos fibers in the air prompted this study. GI cancer incidence data were gathered for Duluth in the same manner as data previously gathered for comparison cities,Minneapolis and St. Paul Although some differences in GI cancer incidence occurred among the three cities in 1969–1971,there was no consistent pattern of statistically significant differences observed. The number of GI cancers diagnosed in Duluth residents in 1972 was similar to that in each of the previous three years. This study represents the start of ongoing cancer surveillance in Duluth.”
We all owe a debt of gratitude to these researchers. If you found any of these excerpts interesting,please read the studies in their entirety.