Environment & Energy
In reply to the discussion: Low-dose study finds no effects [View all]PamW
(1,825 posts)The no-threshold model is predicated on the LACK of a repair mechanism.
The LBNL study has now proved the existence of the repair mechanism because they are the first to actually WATCH the repair mechanism function. Read the paper. They noted that previous studies took "snapshots" of the DNA damage.
The problem with snapshots is the timing. Some researchers took snapshots after the repair mechanism had repaired the damage, and hence they didn't see the repair mechanism in action. Other researchers took snapshots too soon, and the repair mechanism hadn't done its work yet. So both classes of researchers failed to detect the repair mechanism.
The LBNL researchers did a time-lapse look at the DNA, as detailed in their paper. They SAW the DNA repair mechanism at work.
With the existence of the repair mechanism now conclusively proven; we know that there is a threshold at some level. As long as your radiation exposure is within the capacity of the repair mechanism; then you won't have any damage after the repair is done. Naturally, if you get a very large dose, like with the Hiroshima and Nagasaki bombing victims, the repair mechanism is completely overwhelmed, and the response looks more like the linear model for large doses, only.
PamW