One of their wonderful products is a litany of scientifically accurate 3-D animations of DNA, which gets me excited. Of course, my favorite, is DNA damage! But it's too short!
The time horizon of radiation-induced DNA damage is vast:
Time period (approx) Effect
<10^-10 sec: Energy deposition, excitation & ionization, initial partide tracks
10^-10 sec to 1 ms: Radical formation, diffusion chemical reactions, initial damage
1 ms - 1 sec: Resultant DNA breaks/base damage
1 sec - 1 hr: Repair and damage fixation
1 hr -1 day: Cell killing
1 day- 1 year: Mutations/transformations, proliferation of damaged cells
1 year - 1 century: Birth defects, cancer, hereditary effects (in future generations)
Since it takes only about 35 eV to cause a single mutation, think about how many potential mutations a single Cs-137 photon has the potential to cause (energy = 662,000 eV). Fortunately, our DNA repair mechanisms are very good, but not nearly perfect.
Because of that FACT, we conclude there is no radiation dose threshold. The burden of evidence is on someone claiming the existence of a dose threshold and no evidence has been produced in over 100 years of study (lots of messianic yearning and whining though, see my last post).
As mutations accumulate, cancer is a potential outcome (for somatic cells) and/or hereditary issues (for sex cells).
But at typical everyday occupational and general public doses, the benefits far exceed the risks. Which is why we undertake many activities which have associated radiation doses (nuclear power, nuclear medicine, etc.).
Anyways...enjoy the other videos, but don't get too carried away.
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