It’s because they’re required to have exposure as low as reasonably achievable (ALARA). This is actually going away in the US because it’s not actually based on good science. Low amounts of radiation exposure is actually not bad, and it’s not cumulative like it’s normally treated. Even safe levels of radiation exposure must be avoided if possible, even when it increases costs or other hazards.
Video on the change of regulation around ALARA and linear no-threshold (LNT) radiation measurement:
The reasoning behind abandoning ALARA isn’t particularly strong; it’s based on pragmatism and economics of risk, not the underlying biology and chemistry of ionizing radiation exposure. Linear No Threshold is still one of the more conservative models that accurately depicts the impact of ionizing radiation on the underlying biology of adducts, double strand breaks, and associated repair mechanisms.
We’re already in a shooting gallery of radiation exposure due to solar and terrestrial sources; controlling some radiation sources won’t be worth the cost, but that’s where reasonable comes in.
No, LNT is not accurate. It’s accurate at high levels of exposure, not not low. In fact, there is growing evidence that low levels of exposure actually have health benefits (this is not saying to go get irradiated, as we don’t have enough data).
LNT works under the assumption there is no biological repair mechanism. As you say, we are in a shooting gallery of radiation exposure. If we did have a way to handle low levels of radiation exposure then we wouldn’t be alive. LNT causes more harm than it does good, because it causes over-reactions. It’s the same reason breast cancer screening isn’t recommended below a certain age. At a certain point, prevention does more damage than it helps because what you’re preventing is so infrequent that the checks are more harmful than the chance you actually prevent something.
It’s because they’re required to have exposure as low as reasonably achievable (ALARA). This is actually going away in the US because it’s not actually based on good science. Low amounts of radiation exposure is actually not bad, and it’s not cumulative like it’s normally treated. Even safe levels of radiation exposure must be avoided if possible, even when it increases costs or other hazards.
Video on the change of regulation around ALARA and linear no-threshold (LNT) radiation measurement:
https://youtu.be/KT5hYHdelmg
(But also, they’re being exposed frequently. The patient is only once, or a few times.)
The reasoning behind abandoning ALARA isn’t particularly strong; it’s based on pragmatism and economics of risk, not the underlying biology and chemistry of ionizing radiation exposure. Linear No Threshold is still one of the more conservative models that accurately depicts the impact of ionizing radiation on the underlying biology of adducts, double strand breaks, and associated repair mechanisms.
We’re already in a shooting gallery of radiation exposure due to solar and terrestrial sources; controlling some radiation sources won’t be worth the cost, but that’s where reasonable comes in.
No, LNT is not accurate. It’s accurate at high levels of exposure, not not low. In fact, there is growing evidence that low levels of exposure actually have health benefits (this is not saying to go get irradiated, as we don’t have enough data).
LNT works under the assumption there is no biological repair mechanism. As you say, we are in a shooting gallery of radiation exposure. If we did have a way to handle low levels of radiation exposure then we wouldn’t be alive. LNT causes more harm than it does good, because it causes over-reactions. It’s the same reason breast cancer screening isn’t recommended below a certain age. At a certain point, prevention does more damage than it helps because what you’re preventing is so infrequent that the checks are more harmful than the chance you actually prevent something.