Plugged haversian canals and skeleton dose in radium cases

The friction of haversian canals plugged or partially plugged by hypercaclified matrix in skeletons from 30 cases of radium poisoning was found to correlate well with dose, especially as expressed in cumulative rad-yr. There was no significant correlation with age at exposure, age at death, or duration of radium intake either directly or in multiple regression analysis. For 14 of the cases exposed predominantly to 226Ra, cumulative rads (CR) and cumulative rad-yr (CRY) correlated about equally well, but when all 30 cases were considered, including 14 cases exposed predominantly to 228Ra, the correlation coefficient between plugging and CRY was 0.81 (P<<0.01), while that with CR was only 0.48 (P<0.01). Plugging varied approximately as the square root of either CR or CRY within the range of doses observed (1 to 30 krads and 10 to 70 hrad-yr). The expression, (% plugs)sup(1.8), predicts the observed CRY in krad-yr within a factor of two in two-thirds of the cases. Plugging due to radium can probably not be detected below a CR of 1000 rads or a CRY of 10 krad-yr because the normal incidence is the order of 1%. Reduced x-ray score for the same 30 cases also correlated with CRY, but not as well as did the plugged canals. (author)