Here's a story about a lost capsule[0] that ended up being made into building material for the wall of an apartment if you think something small isn't worth being concerned about. [0] https://en.wikipedia.org/wiki/Kramatorsk_radiological_accide...
The equipment to detect high levels of radiation is very cheap. Likewise the equipment to detect lead... And hundreds of other deadly pollutants. Part of owning a house should involve getting it tested, perhaps once per 10 years, for all these contaminants. They might have been put in during construction - or it might be arsenic in the wood of your bed... Or a mixing mistake while making the plastic for your toothbru…
As long as people understand what's a safe level of contamination. There was a problem in New Zealand a few years ago when somebody misread a document describing the level of meth residue that should remain after cleaning up a meth lab and as a result, a whole little meth testing industry popped up and people were selling their houses cheap because of very light contamination being detected. Even an elderly lady in a state house was kicked out because her grandson had smoked meth while visiting. Turned out, that threshold was much lower than the actual safe level for the initial contamination and all these people were screwed over.