the most deadly compounds on Earth. Spike a rat’s water with 10 parts per billion—the equivalent of 7 teaspoons of dioxin dissolved in an Olympic-sized swimming pool—and there’s a 50/50 chance that the rat will die of liver cancer. Yet even tinier concentrations of dioxins fed to rats inhibit tumors. The seemingly paradoxical findings have some scientists suggesting what would have been unthink...

Ethanol (EtOH) often has stimulatory effects at low doses and inhibitory effects at high doses, affecting behavior and physiology of many organisms in a non-linear manner suggestive of hormesis. Zebrafish (Danio rerio) shoaling was studied in adult fish exposed to one of five different EtOH concentrations (v/v): 0.0% control, 0.125%, 0.25%, 0.5%, and 1.0%. Digital photographs of groups of four ...

Perception of hormesis as a significant dose–response phenomenon is found in many sciences without predicting and/or quantifying this low-dose effect with statistical models. Only minority papers published on plant biology or other apply available modelling the relationships, along significance testing for and prediction sub-NOAEL quantities. The threshold quantities opens further evaluation op...

Hormesis describes the drug action of low dose stimulation and high dose inhibition. The hormesis phenomenon has been observed in a wide range of biological systems. Although known in its descriptive context, the underlying mode-of-action of hormesis is largely unexplored. Recently, the hormesis concept has been receiving increasing attention in the field of aging research. It has been proposed...

The purpose of this study is to investigate possible influences of different stressors (saline injections, light deprivation and constant light regimen) and geroprotectors (Epitalon and melatonin) on survivals of female HER-2/neu transgenic mice. We propose a semi-parametric model of heterogeneous mortality (frailty model) for the analysis of the experimental data. In this model, we assume that...

Recently the idea of hormesis, a biphasic dose-response relationship in which a chemical exerts opposite effects dependent on the dose, has attracted interest in the field of carcinogenesis. With non-genotoxic agents there is considerable experimental evidence in support of hormesis and the present review highlights current knowledge of doseresponse effects. In particular, several in vivo studi...

Professor Don Luckey identified the phenomenon of “radiation hormesis,” and he described it in a paper in the Health Physics Society Journal, in 1982. (He also authored two books on this subject.) CRIEPl initiated a research program on radiation hormesis following this publication to confirm, "Is it true or not?" After nearly ten years of research activities on data surveys and animal tests wit...

Jayjock and Lewis’ study “Implication of Hormesisfor Industrial Hygiene” represents a challenge for thescientific community to consider hormesis as a possibleworking hypothesis for redefining risk assessmentstrategy for low-dose exposures in the realm of IndustrialHygiene. This invited commentary aims at examiningsome aspects of the study for which no proven andconcl...