Modelling biphasic hormetic dose responses to predict sub-NOAEL effects using plant biology as an example

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 a minority of papers published on hormesis in plant biology or other sciences apply available statistical modelling of the dose–response relationships, along with significance testing for hormesis and prediction of sub-NOAEL quantities. The prediction of threshold quantities opens many further evaluation options such as risk assessment, hormesis in mixtures or in risk groups, selective hormesis in populations, or assessment of transgenerational hormesis. Therefore, the significance and value of hormesis research can benefit significantly from sound modelling of this biphasic phenomenon. This review is meant to raise awareness of scientists for the value of hormesis modelling.