What would happen to a person if he became radioactive?

Answer 1

Actually you are radioactive. Some of the Potassium in your body is decaying by radioactivity to Argon. This is a small amount however, smaller than the radiation you'd receive from an ionization smoke detector in your house. If you take a plane flight, at higher altitudes you are exposed to charged particles from space, from which the earth's atmosphere usually shields us. So international flights are (slightly) more hazardous, for they spend more time, and at higher altitudes than do domestic ones. This amount of radiation can usually be ignored though, even by flight crew, who spend much more time at altitude than does a passenger.

Focusing closely on the question, a serious radiation dose will cause your hair to fall out, and maybe your gums to bleed. Serious enough, of course, would be fatal. Some of this is because the radiation actually changes the chemical nature of the atoms. (As above with the potassium.) Some of the daughter elements, as they are called, are at least useless, and at worst, toxic.

Answer 2

If a person became radioactive, they could experience symptoms such as nausea, vomiting, hair loss, and potential damage to their organs and tissues. Long-term effects may include increased risk of cancer and other serious health issues. Treatment would involve limiting exposure, decontamination, and medical interventions as needed.