Document B87Gkbjrwjz90Dbz28ZkXyaBX

Asbestos-Like Fibers in Duluth Water Supply Relation to Cancer Mortality Thomas J. Masson, PhD;- Frank W. McKay: Robert W; Miller, MD Asbestos-like fibers in industrial waste first'entered the water supply of Duluth in 1955. In the next 14 years, no carcinogenic effect was apparent in the patterns of cancer mortality among persons of all ages, nor among chil dren. The period of observation is short relative to the latent period for occu pationally induced carcinogenesis from asbestos. (JAMA 228:1019-1020, 1974) HIGH concentrations of asbestos-like fibers have been reported recently in the drinking-water supplies of Du luth, Minn, and other communities on the shores of Lake Superior. Officials of- the Environmental Protection Agency stated that these fibers prob ably came from mine-tailings or mill- From 11m Epidemiology Branch, National Can cer Institute, Bethesda, Md. Reprint requests to A-S21 Landow Bu3<ng, National Cancer Institute. Bethesda. MO 20014 (Or. MiSer). waste from taconite ore, which has been emptied into Lake,-.Superior since 1955.1-1 This pollution has caused concern because occupational expo sures to asbestos are known to induce mesothelioma of the pleura and peri toneum, as well as cancer of the lung, esophagus; and stomach, after a la tent period usually of 20 to 40 years.1 Asbestos fed experimentally to rats has passed through the gastric and intestinal mucosa into the blood stream. Fibers were lodged in gut wall, lungs, brain, omentum, and other organs.4 -To determine if the fibers present in the drinking water of Duluth were related to cancer mortality, we have studied data abstracted from death certificates for all persons who died of cancer in the United States, from 1950 to 1969. Methods The data were made available to rs by the National Center for Health Statistics. We have tabulated the numbers of deaths ascribed to cancer among whites, according to age, sex, and five-year intervals, as well as the age-adjusted cancer death rates for Duluth (I960 population, 105,759), fqr. comparison with :data, for the state JAMA, May 20. 1974 Vol 228. No 8*^-. , Asbestos In Water 3upplyhason et al`"` 1019 DA1UO JOE SMITH. M.O. ASSISTANT MEDICAL DIRECTOR "7 united STATES STEEL CORPORATION