There is a risk that every traveler takes when they get on a flight – one that’s not related to turbulence or unruly passengers. This risk comes from the stars, including our own sun.
It’s called cosmic radiation, according to the U.S. Centers for Disease Control and Prevention. On Earth, the planet’s atmosphere generally protects us from this radiation that consists of charged particles such as protons and Helium ions, the government of Canada noted in its warnings about cosmic radiation. However, that protection decreases the closer we get to that atmosphere.
That’s why flying presents a unique risk. As the CDC explained, “the higher the altitude, the higher the dose of radiation.” Latitude also plays a part in radiation risk, since the Earth’s magnetic field deflects cosmic radiation from the Equator towards the North and South Poles.
So, should people planning to fly to a Disney vacation in California or Florida be concerned? If it’s a rare trip, probably not.
“There’s very little risk to those who fly only occasionally, but frequent travelers and flight crews could face radiation as a greater hazard,” wrote Zach Wichter of USA Today in an article on the risks of in-flight radiation exposure this week.
He said the risks are “especially low for travelers taking domestic flights in the continental United States,” due to that radiation being shuffled off to the poles.
For the average person, cosmic radiation makes up about 11% of their yearly exposure to all natural radiation sources, per the CDC. Radiation from flying is less than the radiation received from one chest x-ray, the centers said.
On the other hand, people who take frequent international flights that cut across the Arctic or Antarctica might be more exposed to cosmic radiation, Wichter noted. He said that new generations are now flying at higher altitudes than before and that over-the-poles routes are now common for international travel, citing the Association of Flight Attendants.
“More frequent travelers and airline crews need to understand that they have a high exposure to radiation and there are tools to track that exposure to radiation and make individual decisions based on that,” Sara Nelson, president of the Association of Flight Attendants, told Wichter. She said that flights to Asia and Europe that cross an ocean are more likely to “fly through a solar particle event.”
According to the Canadian government, those who fly frequently could have annual exposure comparable with, or even exceeding radiation workers in ground-based industries. Still, it said that it “would take about 100 one-way flights between Toronto and Vancouver to obtain the same exposure as we get in one year from other sources of natural background radiation.”
Why is exposure to this radiation a concern? Wichter explained that routine exposure to radiation “can lead to increased risk of cancer and other health-related issues, including pregnancy complications.”
Amber Paul, an assistant professor of Aerospace Physiology and Immunology at Embry-Riddle Aeronautical University, explained to Wichter that: “It’s tricky to say that this particular radiation at this dose causes this effect in this individual because that trajectory isn’t one conclusive trajectory. It’s very personalized.”
