https://digg.com/video/radioactive-gas-radon-tom-scott-tunnel-video
Start a basement garden.
The ideal dosage for seed mutation is around 10-40 Sieverts. Even in a really high radon basement it would take 500 years to get to the low end of that dose. Although it would only take around 20 days in that radon tunnel.
The video pointed to their ability to do a true double blind study; as the tunnel itself is not actually producing the radon but rather the ventilation system.
by your own calculations... these two measured samples of: 636 pCi/L (23,500 Bq/m³) 133.3 pCi/L (4930 Bq/m³) would equal an exposure time of 42-203 days for an ideal dosage.
according to this: https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1263&context=ihpbc
There is no reason why you couldn't replicate this for yourself.
I think that a seeds hull would stop the alpha radiation from radon, but the live plants could receive sufficient dose to mutate the progeny. It seems some plants may sequester radon as well.
A UV-C sterilizer could work too. Ionizing radiation has a good track record for heritable mutations. I would be able to impliment a UV sterilizer in my current greenhouse.
A study on UVB/UVC radiation on seeds (mdpi.com)
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