What Material Can Block Radiation?

There are a number of sources of radiation we can encounter in our everyday lives. 

• Healthcare uses
  • To help diagnose, manage, or treat some health conditions
    • Computed tomography (CT) scans
    • DEXA scans (bone densitometry)
    • Fluoroscopy
    • Nuclear medicine
    • Mammography
    • Radiography and dental X-rays
• In everyday life
  • Air travel
    • Cosmic radiation from space
  • Airport security screening
  • Building materials
    • Those made of concrete, brick, sandstone, natural stone, gypsum, or granite contain naturally-occurring radioactive elements such as radium, uranium, and thorium which may emit low levels of radiation
  • Cigarette smoking 
    • Tobacco contains radioactive materials polonium-210 and lead-210
  • Cell phones and cordless phones
    • Uses radiation (RF) to send signals, which is different from other types of radiation (such as X-rays) that are known to be harmful
    • It is currently unknown if RF radiation from cell phones can cause health problems 
  • Ultraviolet (UV) radiation
    • Sunlight
    • Tanning beds
    • Mercury vapor lighting (often found in stadiums and school gyms) 
    • Some halogen, fluorescent, and incandescent lights 
    • Some types of lasers
  • Wearable computers and wearable technology
    • Typically uses low-powered radiofrequency (RF) transmitters to send and receive data from smartphones or the Internet
    • RF transmitters emit radio waves, a type of non-ionizing radiation
• In nature
  • From space: cosmic radiation
  • From earth: terrestrial radiation
• From nuclear weapons testing

Radiation can damage the DNA in our cells. However, as with many other toxins, radiation damage is dose dependent. We are exposed to low doses of radiation in our daily lives. 

Factors that can affect radiation exposure include: 

• Time
  • Limiting or minimizing exposure time reduces the dose 
  • Exposure to a dose rover a long period of time is less harmful than exposure to the same dose all at once
• Distance
  • The dose of radiation decreases as you move farther away from the source
• How much of the body is exposed 
  • A dose to part of the body causes less harm than a dose to the entire body
• Shielding
  • Lead, concrete, or water barriers can provide protection from penetrating radiation and reduce or eliminate exposure
• Age
  • Children and young adults are more sensitive to the effects of radiation

High doses of radiation may cause:

• Acute Radiation Syndrome (ARS) 
• Cutaneous Radiation Injuries (CRI)
• Cancer later in life
• Harm to a fetus
• Death