Wednesday, February 17, 2016

Effects of Radiation on Pituitary Cancer Mortality

In 1979, R.L. Ullrich et al. compared the pituitary cancer mortality rate of 400 female mice exposed to single doses of 10, 25, 50 and 100 cGy. [Ullrich, R.L. et al. Influence of radiation on the development of neoplastic disease in mice. Radiation Research, 80, 135, 1979.]

The normal mortality from this cancer in the control mice was 6.6% - a value that was set as the 100% or control level on Figure 8.


Caption for Figure 8: Pituitary Cancer in Mice: Source: Ullrich, R.L. and Storer, J.B., Influence of radiation on the development of neoplastic disease in mice. Radiation Research, 80, 135, 1979. (For similar studies by Ullrich et al., see also Radiation Research, 68, 115, 1976, and several other case studies in this chapter.)

As shown, pituitary cancer mortality was decreased nearly 20% at an exposure of 25 cGy, which was similar to results for ovarian cancer (20% decrease), mammary cancer (46% decrease), and uterine cancer (13% decrease). Needless to say, these are not the kind (or even the direction) of results predicted by the LNT.