Flying across the Atlantic exposes passengers to increased levels of cosmic radiation compared to being on the ground, due to the thinner atmosphere at cruising altitudes allowing more high-energy particles from space to reach the body. This radiation dose is often compared to the health risks from smoking cigarettes to provide a relatable perspective.
On a typical transatlantic flight, such as from New York to London, the radiation dose received by a passenger is roughly around 0.03 to 0.05 millisieverts (mSv). This dose varies depending on factors like altitude, latitude, solar activity, and flight duration. For example, flying at higher latitudes near the poles or during periods of high solar activity can increase exposure.
To understand how this compares to cigarettes, it helps to know that smoking a single cigarette exposes the smoker to about 0.01 millisieverts of radiation, primarily from radioactive elements like polonium-210 and lead-210 found in tobacco leaves. This means that the radiation dose from one cigarette is roughly one-third to one-half the dose of a typical transatlantic flight.
Putting this into perspective:
– A single transatlantic flight exposes you to radiation roughly equivalent to smoking about 3 to 5 cigarettes.
– If you take multiple long-haul flights per year, your cumulative radiation exposure from flying can add up to the equivalent of smoking dozens of cigarettes in terms of radiation dose alone.
However, it is important to emphasize that the health risks from radiation and smoking are not directly comparable just by dose numbers. Cigarette smoking causes harm through many mechanisms beyond radiation, including chemical toxins that cause cancer and cardiovascular disease. Radiation from flying is a form of ionizing radiation that can increase cancer risk, but the doses from occasional flights are generally low compared to other sources of radiation exposure.
The cosmic radiation dose during flights comes from high-energy particles originating outside the Earth’s atmosphere. At ground level, the atmosphere and Earth’s magnetic field shield us from most of this radiation. At cruising altitudes of around 35,000 feet, the atmosphere is much thinner, so passengers and crew receive a higher dose rate. Pilots and frequent flyers can accumulate significant doses over time, which is why airline crew radiation exposure is monitored and regulated in many countries.
In contrast, the radiation dose from cigarettes comes from radioactive isotopes naturally present in tobacco plants. These isotopes emit alpha and beta particles that can damage lung tissue when inhaled. The radiation dose from smoking is localized primarily in the lungs, whereas cosmic radiation exposure during flights is more uniformly distributed throughout the body.
To summarize the comparison in simple terms:
– One cigarette ≈ 0.01 mSv radiation dose
– One transatlantic flight ≈ 0.03 to 0.05 mSv radiation dose
– Therefore, one flight ≈ radiation from 3 to 5 cigarettes
This comparison helps put the radiation from flying into a context people can understand, but it should not be taken to imply that flying is as harmful as smoking cigarettes overall. The risks from smoking are much greater due to chemical toxins and the chronic nature of smoking, while radiation exposure from occasional flights is relatively low and considered safe for most people.
For frequent flyers or airline crew, cumulative radiation exposure is a consideration, and measures are taken to monitor and limit doses. For the average traveler, the radiation dose from a single transatlantic flight is small and comparable to a few cigarettes in terms of radiation alone, but the overall health impact is much less than smoking.
In essence, flying across the Atlantic exposes you to a small amount of cosmic radiation roughly equivalent to the radiation dose from smoking a handful of cigarettes, but the health risks from these two sources are very different in nature and magnitude.
