Not actual radiation, but you feel the effects
Usually lead (Pb) because it is a cheap heavy metal.
From nausea and vomiting, all the way to death.
The human body is naturally radioactive. The potassium found in the bodies of humans is the main cause of the radioactivity.
Radioactivity affect the water molecules. Radioactivity makes it harmful
Nuclear weapons testing can have negative impacts on the environment. They can make plants, soil and rain radioactive. This is extremely harmful to humans. Radioactivity can cause mutations in humans and animals.
What other sort of radioactivity is there?
For example natural and artificial radioactivity.
Zues is quite fond of humans.
Radioactivity can be induced in ordinary matter by artificial transmutation.
You cannot measure radioactivity in litres
Radioactivity in Japan is about 15,000 terabecquerels.
Human + A lot of radioactivity = Dead