Many naturally occurring environmental exposures increase risk for cancer. residents in many parts of north america are exposed to low levels of the radioactive gas in their homes, particularly in homes with basements.

Radon

Explanation:

 The radon is one of the type of chemical element with the atomic number 86 and the symbol of the radon is "Rn".

The radon is the radioactive gas and it occur due the breakdown of uranium naturally in the rock, water and the soil form so that it comes into the air where we can breathe.

The main characteristics of the radon radioactive element are as follows:

The radon radioactive gas is usually found in the homes, workplaces and also in the indoor environment. This type of as is very harmful for the human lungs.

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because this was the year that the state of israel was formed