with D equal to microcuries of /sup 226/Ra. An acceptable fit to the head carcinoma data was provided by the linear equation I = C + d alpha. gamma.D/ provided the best fit for the bone sarcomas, when the dose was expressed as microcuries of /sup 226/Ra plus 2.5 times microcuries of /sup 228/Ra. An equation of the form I = (C + BD/sup 2/)e-/sup. For each equation, the best values of the dose coefficients were found by a least-squares fitting procedure. beta.D/sup 2/)e-.gamma./sup D/, where C, the natural incidence for this population, was about 10-/sup 5/ per person-year. To the observed data for each type of tumor were fitted equations that can be formulated from the general form I = (C + alpha dD+. Incidence (I) was expressed as tumor cases per person-year and the dose parameter (D) was the quantity (microcuries) of radium more » that entered the blood during the period of exposure. The relative effectiveness of /sup 226/Ra and /sup 228/Ra and dose-incidence relationships were examined for the 759 of these women whose radium body burden has been determined there are 38 cases of bone sarcoma and 17 cases of head carcinoma in this group. « lessĪmong 1474 women employed in the United States radium dial-painting industry before 1930, there are 61 known cases of bone sarcoma and 21 cases of carcinoma of the paranasal sinuses or the mastoid air cells (''head carcinomas''). A threefold excess risk of death due to multiple myeloma has occurred, but is more closely correlated with duration of employment (a surrogate for external gamma radiation) than with radium intake. Analyses of the breast cancer data uncovered several observations inconsistent with the previously suggested causal association with radium exposure. Lung cancer requires further investigation inhalation exposures of the dial workers were reviewed. Other cancers of the digestive tract appeared to be indirectly, if at all, associated with work in radium facilities. Liver, pancreatic, cervical, and uterine cancers were clearly unrelated to radium exposure. For the 693 cases whose body content of radium has more » been measured since 1955, dose-response relationships of cancer to systemic intake of radium and duration of employment were examined. Mortality was compared with that expected from rates for US white females, with and without adjustment for local area mortality rates, and with mortality in dial workers exposed from 1930 to 1949. The relationships of radium exposure to mortality from cancers of the stomach, pancreas, colon, rectum, liver, lung, breast, cervix, and corpus uteri, and from leukemia were studied in 1,285 pre-1930 dial workers. The female radium dial workers have now experienced significant mortality from cancers other than the bone sarcomas and head carcinomas long known to be radium induced.
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