Living in Colorado, especially in places like Denver that sit at high elevations, means you are naturally exposed to higher levels of background radiation compared to many other parts of the United States. This is primarily because cosmic radiation from space is more intense at higher altitudes due to the thinner atmosphere providing less shielding. On average, a person in the U.S. receives about 6.2 millisieverts (mSv) of radiation annually from all sources, but residents of Colorado can receive a slightly higher dose just from natural background radiation.
When comparing this natural background radiation to the radiation dose from a CT scan, it’s important to understand the scale and context of these exposures. A typical chest X-ray exposes a person to about 0.1 mSv, roughly equivalent to 10 days of natural background radiation. CT scans, however, involve higher doses because they produce detailed cross-sectional images using X-rays. For example, a CT scan of the chest might deliver a dose ranging from about 5 to 7 mSv, which is roughly equivalent to one to two years of natural background radiation in Colorado.
This means that a single CT scan generally exposes you to **more radiation than you would receive from natural background sources in Colorado over the same period**. However, this does not automatically mean the CT scan is “worse” or more dangerous in a straightforward way. The radiation from a CT scan is delivered in a short burst during the imaging procedure, whereas background radiation exposure is spread out continuously over time. The body’s response to radiation can differ depending on the dose rate and duration.
Medical imaging radiation doses are carefully controlled and justified by the benefits of accurate diagnosis and treatment planning. The risk from a single CT scan is generally low, but it is not zero. Repeated scans or unnecessary imaging can increase cumulative radiation exposure and thus the risk of radiation-induced effects, such as cancer, over a lifetime. The risk from radiation exposure increases with dose, but at the levels typical of diagnostic imaging, the increase in cancer risk is small and must be balanced against the clinical need for the scan.
In Colorado, the elevated background radiation means residents already receive a higher baseline dose, but this does not significantly change the relative risk from a CT scan. The natural background radiation is mostly from low-energy sources like radon gas and cosmic rays, which contribute to a steady, low-level exposure. CT scans deliver higher doses in a concentrated way, but the total dose from a single scan is still within safety guidelines established by health authorities.
To put it simply:
– **Background radiation in Colorado is higher than average due to altitude and cosmic rays.**
– **A CT scan delivers a radiation dose higher than daily background exposure, often equivalent to months or years of natural background radiation.**
– **The radiation from a CT scan is a short, controlled exposure, while background radiation is continuous and low-level.**
– **The health risk from a single CT scan is low but increases with repeated exposure.**
– **Medical benefits of CT scans usually outweigh the small risks from radiation exposure.**
People living in Colorado should be aware of their naturally higher background radiation but also understand that medical imaging radiation doses are managed carefully. If you have concerns about radiation exposure from CT scans, discussing the necessity and alternatives with your healthcare provider is important. Sometimes, other imaging methods like MRI, which do not use ionizing radiation, may be appropriate depending on the medical situation.
In summary, while CT scan radiation doses are higher than the background radiation you get living in Colorado, the difference is a matter of dose magnitude and exposure time rather than a simple “worse or better” comparison. Both sources contribute to your total lifetime radiation exposure, but medical imaging is a controlled and justified use of radiation designed to improve health outcomes.