I don't think that's sensible. The burden for crime prevention follows that rule (preventing someone from leaving their home because they may rob someone else

I don't think that's sensible. The burden for crime prevention follows that rule (preventing someone from leaving their home because they may rob someone else requires a heavy burden of proof) but there isn't any assumption of harmlessness encoded anywhere in the legal system. Back in ye olde founders day these sorts of harmful chemicals weren't a consideration that warranted any specific inclusion in the foundation of our laws so I think it's a bit disingenuous to take the lack of any precedent as acceptance.