Asbestos Exposure in the Water Supply and Excess Cancer Mortality

Exposure to hazardous asbestos has been a problem for over a century.  The common form of exposure typically came from the workplace.  However, that has changed as asbestos has been found in the water supplies of various municipalities.  One interesting study is called, "Cancer mortality in relation to asbestos in municipal water supplies." By Wigle DT - Arch Environ Health. 1977 Jul-Aug;32(4):185-190.  Here is an excerpt: "Abstract - The mortality experience of twenty-two municipalities in Quebec grouped by evidence of exposure to asbestos fibers in water supplies (known high, possible high, and probable low exposures) was evaluated. Excess mortality due to cancer of the stomach (males), pancreas (females), and lung (males) was observed in the two municipalities with known high exposures. The excesses among males have been due to occupational exposure to asbestos. The absence of excess mortality due to pancreatic cancer among males suggested that the excess among females was not due to waterborne asbestos. The study therefore did not reveal evidence of excess cancer mortality that could be attributed to exposure to asbestos in drinking water."

A second study is called, "Lung function consequences of dust exposure in asbestos cement manufacturing plants." By Weill H, Ziskind MM, Waggenspack C, Rossiter CE -
Arch Environ Health. 1975 Feb;30(2):88-97 – Here is an excerpt: "Abstract - A comprehensive study of health effects associated with the mixed dust exposure in this industry has included the collection of clinical, radiographic, lung function, and dust exposure data on 859 workers in two plants. Evidence is presented supporting a dose-response relationship between indexes of dust exposure and lung function, similar to the previously reported relationship with extent of x-ray film changes using the ILO U/C classification. Lung volumes and maximum expiratory flow rates decrease in relation to increasing cumulative dust exposure while pulmonary diffusing capacity (DL) is not dust-dose related. Worders who had crocidolite exposure had smaller lung volumes, lower expiratory flow rates, and reduced DL when compared with those having only chrysotile exposure. When the study population is divided into exposure groups, data thus far analyzed suggest that the chest x-ray film will reveal small opacities as early as significant functional changes can be detected, but individuals may have functional reduction prior to the appearance of x-ray film changes."

A third study is called, "Asbestos-related mesothelioma: factors discriminating between pleural and peritoneal sites." By K Browne, W J Smither - British Journal of Industrial Medicine 1983;40:145-152.  Here is an excerpt: "Up to the end of 1980, 144 confirmed cases of mesothelioma were identified among employees of an organisation using asbestos in manufacturing and insulation. The primary site was peritoneal in 74 cases, pleural in 66, and undetermined in four. All employees had been exposed to amphibole asbestos, and evidence from different factories confirmed the predominant role of crocidolite in the production of mesothelioma. The ratio of pleural to peritoneal sites showed a continuous change when related to the year of first exposure, varying from 5:1 pleural to peritoneal before 1921 to 1:3 after 1950. The strong temporal relationship appeared to reflect progressive dust suppression, including the non-fibrous dusts present in insulation materials and perhaps also the degree to which the fibres had been opened. Other predisposing factors were related to the degree of individual exposure, the peritoneal site being associated preferentially with longer and heavier exposures."

If you found any of these excerpts, please read them in their entirety.  We all owe a debt of gratitude to these researchers.