Does low level ionizing radiation exposure cause cancer?

This paper examines the various dose-response curves for low level radiation response, paying particular attention to potential sources of uncertainty and confounders in human radioepidemiologic studies. It is concluded that there is no single or simple dose-response characterizing radiation carcinogenesis in humans, and that each carcinogenic end point win have its own specific characteristic dose-response which may or may not be linear, and may or may not have a threshold.