Radioactive Materials (3)

Radioactive materials have the same chemical properties as the nonradioactive forms. Thus, radioactive iodine (I131), for example, can be incorporated into thyroxin, the thyroid hormone, as easily as nonradioactive iodine (I127). Strontium 90 is a radioactive substance. It is chemically very similar to calcium, and thus tends to be accumulated in the bones and other tissues rich in calcium. It can also damage the blood-forming center in the bone marrow.