The radioactive gas radon can be a risk in the basements of stone houses and used to, erroneously, be touted for its health benefits, says Prof Allan Blackman from AUT in ep 69 of Elemental.

Radon was originally named 'radium emanation' by its discoverer, Kiwi chemist Lord Ernest Rutherford.

It is a noble gas and is produced by the radioactive decay of uranium and thorium. People who live in stone buildings can be at risk from radon gas as it escapes from rocks - it is heavy so it tends to lodge in the basements of houses. This is a problem in some parts of the United States, where you can buy radon detectors in supermarkets, but is not an issue in New Zealand.

In the early twentieth century radon was touted as having health benefits before the dangers of radioactivity were recognised, says Professor Allan Blackman from the Auckland University of Technology in episode 69 of Elemental.

Go to this episode on rnz.co.nz for more details