Comment on "Stress induction in the bacteria Shewanella oneidensis and Deinococcus radiodurans in response to below-background ionizing radiation", Castillo, et al. Int. J. Rad. Biol., 2015; Early Online DOI:10.3109/09553002.2015.1062571

TL;DR

This paper comments on a study suggesting bacteria may experience hormesis from background radiation, proposing experiments to test if radiation products accumulate in their growth medium over time.

Contribution

It critically discusses prior findings on radiation hormesis in bacteria and proposes new experiments to investigate the underlying mechanisms.

Findings

Background radiation may induce hormesis in bacteria

Radiation products could accumulate in growth medium over time

Further experiments are needed to confirm mechanisms

Abstract

Castillo, et al. report hormesis by background levels of radiation, at which there is $< 10^{-3}$ ionization per bacterium in a replication time. This suggests radiation products accumulate in the growth medium over much longer times. Experiments are proposed to test this hypothesis.