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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."
The article says low levels of exposure for five weeks resulted in no DNA damage. Five weeks is nothing, people living in contaminated areas will be there for years, and once radioactive material gets inside them it will be there for the rest of their lives. That is where the biggest danger is, long term internal exposure to material absorbed by the body into the organs.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
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!
Probably you should not trust that one study. Currently, that is the only study that lead to this conclusion. Public safety regulation should not be lowered based on a single study.
Once the result has been succesfully reproduced in multiple independent labs, then the question will be different.
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"?
This study would need to be much longer term and need to look for more than obvious DNA damage for me to trust it,
This study will never be trustworthy.
The danger to civilians from a nuclear accident is unlikely to come from background dose. That's more likely to be the exposure mode for workers and people very close to the incident.
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.
No surprises there, but they didn't test what would happen when the mice ingested radioactive particulates, or when their entire food chain or water table was contaminated. Those are the real dangers from nuclear accidents.
"I've got more toys than Teruhisa Kitahara."
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
The amounts were tiny, but randomly sized/distributed particulates are notoriously hard to measure and map.
"I've got more toys than Teruhisa Kitahara."
Do you live near a freeway? That doubles the rate of atherosclerosis. Air pollution kills hundreds of thousands a year in the US, and also causes other significant morbidity like asthma in children. Way more dangerous that a measly radiation dose. Yet, I don't see people wanting to evacuate from around coal plants and freeways.
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
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!
Not that much longer, a mouse goes from infancy to maturity in about 6 to 10 weeks, a year can get you a generation or two. A mouse can have 5 - 10 litters in a year and their lifespan is 9 to 12 months; 5 weeks for a mouse is like 20 years for a human.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Sophisticated molecular and genetic analyses were not available in 1950s - 70s when many experiments investigating the effects of radiation on plants and animals took place; most were crude LD50 and cancer frequency tests conducted at moderate to very high doses, few were conducted at low doses (0.1 Gy) where cells could potentially repair the damage caused. This has all changed in the last ~20 years.
Sophisticated laboratory techniques now detect and observe the defence & repair mechanisms that operate in cells and whole organisms at low doses (100 mSv, ~0.8% increased risk of cancer in humans). For example, healthy people's cells repair all radiation induced DNA Double Strand Breaks (DSBs) within 24-hours after a CAT scan, indicating little or no additional risk of cancer. It is clear from resent experiments that living organisms are not passive accumulators of radiation damage but they actively combat and repair the damage done. After all, life involved with radiation and 3.5-3.8 billion years ago radiation levels were many times greater then now, it was necessary to evolve sophisticated error correction mechanisms. Indeed, it is likely that radiation is far less harmful or harmless below a certain threshold, possibly ~ 20 mSv year.
Crump, K. S. et al. 2012. A Meta-Analysis of Evidence for Hormesis in Animal Radiation Carcinogenesis, Including a Discussion of Potential Pitfalls in Statistical Analyses to Detect Hormesis. Journal of Toxicology and Environmental Health, Part B 15, 210–231.
Neumaier, T. et al. 2012. Evidence for Formation of DNA Repair Centers and Dose-Response Nonlinearity in Human Cells. PNAS 109, 443–448.
Löbrich, M. et al., 2005. In vivo formation and repair of DNA double-strand breaks after computed tomography examinations. Proceedings of the National Academy of Sciences of the United States of America 102, 8984 –8989
Tubiana, M., Feinendegen, L. E., Yang, C. & Kaminski, J. M., 2009. The Linear No-Threshold Relationship Is Inconsistent with Radiation Biologic and Experimental Data. Radiology 251, 13–22. (Paper available without subscription).
Maybe, but 5 weeks for mouse's DNA is like 5 weeks for human's DNA.
It's like the birds and rodents living happily in Chernobyl.
Who cares if you get a cancer after 15 years of radiation if your average life expectancy is 10 years?