smoke detectors
Americium 241 or Radium 226
The main hazard of the ionizing type detector is the radioactive component, usually Americium 241, which has a half-life of 458 years. Radium 226 has a half-life of 1600 years. Americium is a waste product from nuclear reactors.
It is easily absorbed into the body from the lungs or intestines, and can cause cancer and genetic injury or can have general negative effects on health.
A typical Americium source contained in one ionizing detector intended for home use, would consist of 0.8 to 5.0 micro curies of Americium on a silver disc, coated with a very thin layer of gold. An industrial model may contain up to 15 micro curies. We usually speak of picoCuries of radiation, which are one millionth of a microCurie, as having biological significance for humans.
Have a nice day...
Am-241 decays by alpha emmission
One inch of air will stop all alpha emmissions from your smoke detector. And if you get closer than that, the outermost layer of dead skin cells will stop alpha from reaching living tissues.
Don’t eat your smoke detector.