Are X-rays Dangerous? What You Should Know

Diagnostic imaging studies can be extremely valuable in the diagnosis of illness and disease. However, people often ask questions about the potential risks associated with these procedures. The general risks associated with certain diagnostic imaging procedures are described below, but it is important to discuss these risks and any questions you have with your doctor.

What imaging studies involve radiation?

• X-rays
• CT or CAT (computerized tomography) scans
• Nuclear medicine studies
• PET (positron emission tomography) scans, bone density scans
• Mammograms

Please note: MRI (magnetic resonance imaging), MRA (magnetic resonance angiography) and Ultrasound (or sonogram) do not involve radiation.

What are the risks?

The primary risk associated with some diagnostic imaging studies are adverse effects of radiation exposure, which may increase the risk of developing cancer.  In most cases, the exposure to radiation is generally so small that the benefit of the study far outweighs the risk due to radiation exposure.

Is radiation exposure dangerous?

We are exposed to radiation from natural sources all the time. According to recent estimates, the average person in the U.S. receives an effective dose of about 3 millisieverts¹ (mSv) per year from naturally occurring radioactive materials and cosmic radiation from outer space. These natural "background" doses vary throughout the country. To explain it in simple terms, we can compare the radiation exposure from one chest X-ray as equivalent to the amount of radiation exposure one experiences from our natural surroundings in 10 days.²

¹Millisievert is the scientific unit of measurement for radiation dose.

²Source

How can I limit my exposure?

•     Keep a record of all of your past imaging studies, especially those requiring radiation.
•     Discuss with your doctor the risks and benefits of having the study in the first place and any potential alternative testing that may not include exposure to radiation.
•     Understand the purpose of the study and know why it is being recommended for you.

More information

For more information on imaging studies and radiation safety, visit Radiology Info.