Your yearly radiation exposure is 620 millirems (.62 rems), according to the National Council on Radiation Protection and Measurements (NCRP), for the average person living in the United States. About half of this radiation is from environmental sources, and about half is from man-made sources.
Common environmental radiation exposure is from the atmosphere, the ground and even your body. Common man-made radiation exposure is mostly from medical sources: X-ray machines, medical devices and procedures. It’s good to be aware of where radiation comes from and reduce our exposure to it when possible.
There is a difference in the amount of radiation we are exposed to when flying in an airplane than when going about our lives at ground level. When on an airplane, we are not as protected by the earth’s atmosphere, and most of the extra radiation we are exposed to comes from either outer space or the sun.
In general, space radiation, also known as galactic rays or galactic cosmic rays, is higher in energy than solar radiation (from the sun). Higher energy radiation can cause more cellular damage to our bodies.
Here are some factors that affect how much radiation we are exposed to:
Clouds are the predominant atmospheric condition that determines the amount of solar radiation that reaches the earth. For any given location, there is less solar radiation reaching the earth’s surface the cloudier it is. A cloudy day offers protection from solar radiation. This is something we all have heard when trying to prevent a sunburn on a sunny day.
In general, more solar radiation is present in the middle of the day than during either the early morning or late afternoon. At midday, the sun is positioned high in the sky and the path of the sun’s rays through the earth’s atmosphere is shortened. At midday, a shorter path to the earth means less solar radiation is scattered or absorbed by other objects (such as clouds) and more solar radiation reaches the earth’s surface. At night there is no solar radiation because there is no sun.
Chronic radiation exposure
There’s a delay in health effects seen from chronic exposure to radiation, because exposure to radiation adds up over time. According to the Environmental Protection Agency (EPA), effects from chronic radiation exposure can include cancer, benign tumors, cataracts and possibly harmful genetic changes.
Low-level radiation exposure
According to the EPA, there is a suggestion of low level exposure and cancer. However, this area is still being researched. It’s more difficult to scientifically research this area because of the delay between when radiation exposure occurs and when health effects are seen.
Radiation facts
- The average US person is exposed to 620 millirem of radiation per year.
- The annual public dose limit is 100 millirem of radiation per year, according to the US Nuclear Regulatory Commission (NRC).
- An average domestic flight is about one millirem (.94 millirem) of radiation dose according to an American Association of Physicists in Medicine (AAPM) report.
- One round-trip transatlantic flight is a little more than three dental X-rays.
Here are some things that affect how much radiation there is:
- Distance. Radiation increases with altitude—how high you fly. The higher you fly, the more radiation exposure you get.
- Time. The longer you are in the airplane, the more radiation you are exposed too.
- Flight path. Radiation levels are higher at the equator. The closer you fly to the equator, the higher your radiation exposure.
Here are some things you can do about it:
- If possible, avoid midday flights. Fly early in the morning, late in the afternoon or at night. Night is the best because there is no solar radiation at night. (It’s night, right?)
- If feasible, take a smaller plane. Smaller planes tend to fly at lower altitudes.
- If available, choose the shortest path to your destination. This lowers the time you’re at a higher altitude, and therefore lowers your radiation exposure levels.
- If on a longer flight, pick a flight path farthest from the equator.
- Eat lots of berries (all kinds of berries). They are high in antioxidants and fight free radical cell damage. Blueberries, goji berries, strawberries, blackberries, cranberries — all are very high in antioxidants. Plus they’re good for you, too!
- Dark chocolate is a excellent antioxidant — and decadent.
- Go a little nuts! Walnuts, pecans, almonds and peanuts are all good antioxidants.
Dried berries, dark chocolate and nuts — sounds like trail mix to us!
- Have a cup of tea. Green tea, that is. Green tea is a great antioxidant.
- Grab SAMe (S-adenosylmethionine) supplements. SAMe is naturally occurring in our bodies and is involved in many metabolic processes — including the immune system and, more specifically, cell membrane repair.
- Take a bath. Take time to relax after the stress of flying. Relaxing will allow for optimal immune function. The immune system is responsible for repair of free radical damage in our bodies. If available, use Epsom salts, which contain magnesium sulfate. There is some evidence that you can absorb it through your skin, and magnesium is used in many body functions. We want our whole body to be functioning well.
Protect yourself
It’s good to be aware of the influences of our environment. While some natural background radiation is unavoidable — it’s just part on living on planet earth — there are radiation exposures where you do have a choice. We recommend looking at how much you fly. Also what is your current state of health? Do you have any special concerns? All of these factors go into how you respond to radiation exposure.
Through understanding our environment, we can take precautions that are effective for us. Many of the suggestions here are easily doable and very healthy, too! We advise you to understand your options, take your health into your own hands and do what you feel is best for you.
—Nikki Walsh
Nikki Walsh is a freelance writer and mom of two kids living in Southern California. She holds an MBA in marketing from University of California, Irvine and a bachelor’s degree in Biochemistry from UCSD. She has been practicing Kelee meditation for 19 years. When she is not writing she can be found out and about having fun with her kids.
Sources:
http://www.aapm.org/pubs/reports/RPT_217.pdf
http://www.nrc.gov/about-nrc/radiation/around-us/doses-daily-lives.html
https://www.epa.gov/radiation/protecting-yourself-radiation
http://www.who.int/uv/uv_and_health/en