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MIT Study: Prolonged Low-level Radiation Exposure Poses Little Risk
JSBiff sends this quote from MITnews:
"A new study from MIT scientists suggests that the guidelines governments use to determine when to evacuate people following a nuclear accident may be too conservative. The study (abstract), led by Bevin Engelward and Jacquelyn Yanch and published in the journal Environmental Health Perspectives, found that when mice were exposed to radiation doses about 400 times greater than background levels for five weeks, no DNA damage could be detected. Current U.S. regulations require that residents of any area that reaches radiation levels eight times higher than background should be evacuated. However, the financial and emotional cost of such relocation may not be worthwhile, the researchers say."
Funny, but "no detectable DNA damage" is not the same as "no DNA damage or other side effects". This study would need to be much longer term and need to look for more than obvious DNA damage for me to trust it, personally. It was only 5 weeks!
The interesting thing to note (if this study is correct) is that they observed a difference between an acute dose and a chronic one. Our radiation health data is mostly based on acute doses - the Hiroshima and Nagasaki bombings, mainly. The low dose risk estimates are basically based on that, extrapolated downwards linearly.
If acute dosing behaves differently to chronic, that model wouldn't be appropriate.
The interesting thing to note (if this study is correct) is that they observed a difference between an acute dose and a chronic one. Our radiation health data is mostly based on acute doses - the Hiroshima and Nagasaki bombings, mainly. The low dose risk estimates are basically based on that, extrapolated downwards linearly.
If acute dosing behaves differently to chronic, that model wouldn't be appropriate.
Hiroshima and Nagasaki radiation victims are some of the few human models that have been studied, but the DOE (and probably other government agencies around the world) did extensive testing on the effects of radiation at various doses using animal models. In one large-scale study I know of they used two exposure groups of beagles, one using the radioactive isotopes the bomb victims were exposed to in order to establish a baseline model correlation (human effects vs. effects observed in laboratory animals) and the other group exposed to isotopes expected to result from nuclear accidents and the new generation hydrogen bombs (different fallout characteristics than the original atomic bombs). Quite a bit of research was done on this, especially during the 1960s and 1970s. They also experimented with direct gamma exposure at various levels; rumor has it (I've never seen published results on the experiments) that there was a sweet spot in the gamma ray exposure scenario that actually lead to significantly longer lifespan than the control group, with many theories as to the cause.
once radioactive material gets inside them it will be there for the rest of their lives.
Wrong. Many radioactive isotopes aren't absorbed by the body and are flushed out rapidly, and some of the most damaging particles (alpha emitters in particular) are at their worst when airborne, only staying 'in' your body for the length of a breath. There are some isotopes that are absorbed easily (namely Iodine), but they are the minority. There is not a single "Radiation", there are a staggering number of different radioactive elements, and for each one, the chemistry matters far more than the half-life.
If you follow the links to the abstract, it actually explains what they measured. Apparently, certain types of DNA damage leave easily measured chemical signatures. They also dosed them with the same radiation total over a short period of time and observed damage.
This is akin to turning your thermostat up 10 degrees for a few weeks as opposed to heating your house up to 500 degrees for a minute.
I'm not saying I want to invest in cheap Fukushima real estate. I'm just saying that maybe this science isn't as junky as some Slashdotters think.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
Btw, 100x background for 5 weeks is still less than the maximum year-long dose. Check the should-now-be-iconic xkcd radiation chart.
Those who fail to understand communication protocols, are doomed to repeat them over port 80.
Uh, is this a penis enlargement joke? Because I don't think radiation does that.
It does if radiation excites you sexually.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Are you talking about chemical poisoning, or magical evil pixie dust. 125I decays emitting low-energy gamma radiation (the type that gets adsorbed adversely by living things). Eating this will have no different an affect than living right under it, as an object like a person, or mouse, is not a relevant shield for gamma radiation.
Now, if we were talking about inhaling dusted alpha emitters, then you'd have a point. However, those are either heavy metals, oxidize and drop out of the air, or decay rapidly to long-term emitters. The dust will be much more poisonous than dangerous as a radioisotope.
Damnit, I fed the troll.
There's nothing I detest more than some douche who has spent some time
at a university telling us all "we have nothing to fear".
Oddly, there's nothing I detest more than some idiot who is terribly afraid of something long after it's been proven to be safe.
I'd happily live in an area with 200x the level of background radiation (hey, my AT&T reception couldn't get any worse). The best benefit is that I can be sure compete morons like yourself will not be neighbors.
They said that about DDT.
Um, yeah...because DDT is safe. And millions have been killed from malaria that could have been saved without idiots like yourself "protecting" them.
Moron.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Maybe you, and the mods, might want to familiarize yourself with lab mice. They are precisely breed.
We know pretty much everything about them. For example, you can get mice that will get a specific cancer at 2 months, and it happens every time. 'only' 99.9% guarantee, but I have never seen one in a control not get cancer at the expected time
SO, for this test, 5 weeks is fine. But with ALL STUDIES, one isn't enough. DO several, control different variables, move to different species.
The Kruger Dunning explains most post on