Alex WellersteinVerified account

I hate getting in discussions about hormesis, as an aside, because non-scientists are easily suckered into the hormesis agenda (because they like to believe it might be true, or something), and don't realize how skimpy the evidence is.

Hormesis advocates have done a good job of making it seem, on the Internet, like this is a mainstream idea. My discussions with, and readings of, health physicists and geneticists, suggest it is not at all.

Compounding this is that most people DO have a pretty terrible understanding about the risks of radiation, so it's easy to fall into the trap of, "most people exaggerate it, so maybe people on the total other side of the spectrum are right!" Which is just a cognitive error.

The people I talk to who don't seem to have an ideological dog in this fight and who are informed are generally of the "LNT seems to work pretty well; the newer, larger datasets in the last few years seem to back it up; the hormesis people vastly overstate their case" view.

Nobody asserts that we totally understand the effects of very-low level radiation, but the LNT thesis assumes that in our ignorance, we should be wary about exposing large populations to low levels of radioactivity. The hormesis thesis instead assumes we can be cavalier about it.

Was with you until the final tweet. As scientific hypotheses, neither LNT or hormesis "assumes" anything our attitudes or policies. LNT is right, or hormesis is right, & we may not know which yet, but that doesn't say anything about what policies are best.

There are different ways one can interpret uncertainty in risk, to be sure. Some people (and countries) are of the "don't worry about it until you have seen a lot of evidence of harm," some are of the "be precautionary about risk unless you know it's safe."

In the US we tend to use the former and in Europe they tend to use the latter. In the case of things like radiation, where we do have evidence of harm at a variety of exposures, I think it makes sense, in the face of uncertainty, to err on the side of preventing harm.