A bone scan is also useful for finding cancer that has spread (metastasized) to the bone from a tumor in another organ, such as the breast or prostate. A bone scan can detect certain leukemia and lymphoma-related abnormalities. In patients with these disorders, increased activity within the bone marrow results in higher than normal levels of radiation on the bone scan. In addition, a bone scan may show other problems not related to cancer. For example, a bone scan may show abnormal levels of radiation if you have been exposed to radiation at a nuclear power plant accident site. The test is also sensitive to the use of certain drugs that increase calcium loss through the urine or prevent bone breakdown. A radiologist will read the bone scan images to look for areas of high activity which might indicate metastasis or other problems. High levels of radiation are always dangerous. You should never go into any area where radioactive material is being handled without special protective clothing and equipment. If you are around radiation all the time, it is important that you do not develop a habit of ignoring its effects. Some people claim that radiation does not cause health problems until many years after exposure, but this is not true. Any amount of radiation over long periods of time can be harmful. The more frequently you are scanned, the less radiation you receive overall.