Objective: Nuclear medicine technologists work under sig­ nificant radiation protection constraints. These constraints are based on the linear no-threshold (LNl) radiation para­ digm, which was developed in the 1960s and was based largely on the deleterious effects of radiation as they were understood at the time. More recently, the theory of radia­ tion hormesis, or a beneficial effect of low-...

Personal reflections on radiation hormesis for the past 50 years are presented. The causes of ignoring and rejections of this phenomenon by international and national bodies and by radiation protection establishment are analyzed. The opposition against nuclear weapons and preparations for nuclear war was probably the main factor in inducing the concern for adverse effects of low doses of ionizi...

The atomic bomb survivor cancer mortality data have been used in the past to justify the use of the linear no-threshold (LNT) model for estimating the carcinogenic effects of low dose radiation. An analysis of the recently updated atomic bomb survivor cancer mortality dose-response data shows that the data no longer support the LNT model but are consistent with a radiation hormesis model when a...

In medical applications of statistics, such as drug testing or risk assessment, most investigators usually expects linear dose-response pattern and is rather surprised finding that the effects on some individuals are even opposite than those expected from the assumption of linearity. We provide several examples of the non-linear doseresponse pattern, the phenomenon called hormesis, both chemica...

Confounding factors in radiation pulmonary carcinogenesis are passive and active cigarette smoke exposures and radiation hormesis. Significantly increased lung cancer risk from ionizing radiation at lung doses < 1 Gy is not observed in never smokers exposed to ionizing radiations. Residential radon is not a cause of lung cancer in never smokers and may protect against lung cancer in smokers. Th...

Free living organisms typically occur in harsh environments challenged by abiotic stresses of varying intensities. Taking ionizing radiation and caloric restriction as examples, environmental variation from benign to extreme gives a fitness-stress continuum where energetic efficiency, a measure of fitness, is inversely related to stress level. Hormesis occurs in benign regions for these example...

There is considerable evidence from experimental studies in animals, as well as from clinical reports, that low-dose radiation hormesis is effective for the treatment of cancer and ulcerative colitis. In this study, we present 3 case reports that support the clinical efficacy of low-dose radiation hormesis in patients with these diseases. First, a patient with prostate cancer who had undergone ...

background: hormesis is defined as the bio-positive response of something which is bio-negative in high doses. in the present study, the effect of radiation hormesis was evaluated on the survival rate of immunosuppressed balb/c mice by cyclosporine a. materials and methods: we used 75 consanguine, male, balb/c mice in this experiment. the first group received technetium-99m (3700bq) and the sec...

Photon hormesis refers to the phenomenon where the biological effect of ionizing radiation with a high linear energy transfer (LET) value is diminished by photons with a low LET value. The present paper studied the effect of photon hormesis from X-rays on dose responses to alpha particles using embryos of the zebrafish (Danio rerio) as the in vivo vertebrate model. The toxicity of these ionizin...