A Fishy Story
credit: NOAA
Some media outlets have picked up on a new study published in the journal Environmental Science and Technology. (More on that coverage in a minute.) Here’s the headline from the Oregon State University press release:
Study finds only trace levels of radiation from Fukushima in albacore
The scientists seemed to make sure their results were put in proper context. From the second graph:
In fact, you would have to consume more than 700,000 pounds of the fish with the highest radioactive level – just to match the amount of radiation the average person is annually exposed to in everyday life through cosmic rays, the air, the ground, X-rays and other sources, the authors say.
If you’re a newspaper editor, how do you capture a study like this in a headline? British editors varied.
The Independent threw out typical bait:
Radioactive tuna fish from Fukushima reactor caught off American shores
The Daily Mail did the same, but more cleverly:
Oregon fisherman catch radioactive tuna contaminated by Fukushima disaster-but scientists say they’re SAFE to eat
You get it? Wink, wink. The “radioactive tuna” is still safe to eat!
Elsewhere, media headlines also varied. Some closely reflected the study’s findings:
Fukushima radiation: Minute amount found in Oregon tuna
Others, such as Reuters, seemed intent on capturing eyeballs:
Study finds Fukushima radioactivity in tuna off Oregon, Washington
Although the Reuters piece hewed closely to the perspective of the researchers–who don’t find their results worrisome–one of the authors of the study is quoted as saying:
The levels [of radiation] were way too small to really be a food safety issue, but we still want to tell people about it so they know what’s there.
You know, in case you want to avoid radioactive fish. The same researcher also said this:
You can’t say there is absolutely zero risk because any radiation is assumed to carry at least some small risk. But these trace levels are too small to be a realistic concern.
Confused? Don’t be. Just read this piece of advice given during the last Fukushima fish freak out.
follow along here > reactors at fukushima exploded and released tons of radioactive particles into the ocean > these tiny radioactive particles were ingested by a tuna > let’s call him “Charley the Tuna” > a fisherman caught Charley and placed him on ice (Charley is now dead) > some researchers from the State University wave a geiger counter over Charley’s cold corpse and discover slightly higher radioactive levels than normal and reported this to the media > the media reports that radiation levels are higher but not dangerous for human consumption > humans and cats consume Charley and the tiny radioactive particles get stuck in their muscle tissue and bombard surrounding cell tissue with low levels of radioactivity and eventually the human or cat gets some horrible cancer and dies > low radioactivity, close proximity and long term exposure = death
I heard that when you go out in the SUN, that the sunlight is actually RADIATION. There is actually even UV radiation in the sunlight! (grin).
I wonder if people know that anytime they go out into the sun they are actually exposed to RADIATION.
Just to be clear: If you are starting from the premise that extremely low levels of radioactivity = death, then life = death.
yes, we all eventually die and there is natural occuring radiation > there is however no naturally occurring cesium 137 > some left over from the above ground nuclear tests > more spin from coreyspowell > speck of low level radioactive isotope in your muscle tissue radiating nearby celluar tissue for 25 years causing cancer equals unnatural death
What a bleak frightened life you must live, being afraid of food. Chemophobes and nucleophobes make me laugh. If you actually read the paper you will see you are exposed to thousands of times more radiation on a daily basis. Read the paper.
There is literally more radiation in a normal banana than in one of these fish.
Keith, I haven’t seen you wade into the ocean acidification issue yet.
The Seattle Times has “VITAL PART OF FOOD WEB DISSOLVING” and “CO2 dissolving vital part of food web”.
Is the ocean about to become a Dead Zone? Now that Thermageddon fears are dissolving, do pteropods have to dissolve to get us back on track?
I would be willing to bet that if it could even be measured the affect on your life expectancy from consuming a typical amount of the affected tuna would be measured in hours.
It’s not widely known, but actually, a modest amount of radiation may be beneficial:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2889502/
“Current guidelines for limiting exposure of humans to ionizing radiation are based on the linear-no-threshold (LNT) hypothesis for radiation carcinogenesis under which cancer risk increases linearly as the radiation dose increases. With the LNT model even a very small dose could cause cancer and the model is used in establishing guidelines for limiting radiation exposure of humans. A slope change at low doses and dose rates is implemented using an empirical dose and dose rate effectiveness factor (DDREF). This imposes usually unacknowledged nonlinearity but not a threshold in the dose-response curve for cancer induction. In contrast, with the hormetic model, low doses of radiation reduce the cancer incidence while it is elevated after high doses. Based on a review of epidemiological and other data for exposure to low radiation doses and dose rates, it was found that the LNT model fails badly. Cancer risk after ordinarily encountered radiation exposure (medical X-rays, natural background radiation, etc.) is much lower than projections based on the LNT model and is often less than the risk for spontaneous cancer (a hormetic response). Understanding the mechanistic basis for hormetic responses will provide new insights about both risks and benefits from low-dose radiation exposure.”
I doubt that the amount in the fish remotely rises to a level that could cause any concern.
Wow, you are right. I’m going to go hide in the closet the rest of my life.
Edward:
First, we surveyed these albacore by first ashing them down to concentrate all the cesium from a couple kilos (per fish) to a very small volume, otherwise we wouldn’t be able to detect these trace levels at all. We then surveyed them using a gamma spectrometer to determine how much Cs-137 and Cs-134 (when present) was there. If you surveyed these albacore with a geiger counter, you wouldn’t see any difference…milliBecquerels of a change in Cs-137 in a whole albacore is too small compared to the variation of the hundreds of Becquerels of natural K-40 present.
Second, cesium follows a two compartment model in the human body, one fraction with a biological half-life of 2 days and the rest with a biological half-life of 110 days. They do not get “stuck” in your muscle tissue permanently, within a year 87.5% of the activity ingested will have been flushed from your body. The doses referenced in the press release are after accounting for how long it takes cesium to be removed from your body.
Third, if you are over the age of 14 you have likely consumed tuna with the same traces levels we are currently finding, owing to a larger fraction of atmospheric weapons testing fallout being present in the surface layer of the ocean.
Finally, if you do feel these trace levels qualify as a risk concern for you, there are far greater exposures you are going to experience from other sources, and I’d be happy to give you some guidance on avoiding such doses (and while I find it irrational, I know there are some people who would agree with you, which is why we felt it better to tell the public rather than remain quiet).
I am glad to see a response that puts in perspective the findings for the general audience. Many times we forget that the general public, and even other researchers that are not experts in the topic at hand may not understand what the findings mean and take it out of context.
a personal attack > are you aware of the impact that the 3 melting fukushima reactors are having on the pacific ocean?
and that’s ok?
I appreciate the thoughtful reply Delvan and will look into this some more > what raised flags for me was there were 4 or 5 of these same articles in major publications countering fears of eating tuna fish > there are huge dollars at stake > regardless of the current levels of radiation in these fish the overall exposure is growing > there is no known solution for the 3 melting nuclear reactors in Fukushima Japan > the New York Times ran an article a few days ago about how the Japanese Government was lying to people telling them it was safe to return > I am cynical > biostitutes and presstitutes abound > and for the record i had a tuna fish sandwich at subway this week > i know there is no escaping the pollution > watch “Trinity and Beyond” at Netflix to get the scope of how much radioactive material was launch into atmosphere during the above ground nuclear tests
what constitutes this writer as an “expert” > “experts” said that Sadam Hussein had weapons of mass destruction > Colin Powell lied to millions on TV pointing to biological weapons facilities which didn’t exist > the Iraqi National Congress was a complete work of fiction created by the Rendon Group at a cost of 350 million dollars a month > we live in a public relations “Truman Show” > read “Propaganda” by Edward Bernays
There’s an EPA handbook that lists dose conversion factors (that is, the committed effective dose you get from consuming radioactive things) expressed in terms of risk of a fatal cancer or non-fatal cancer, here. It’s the best aid I’ve found for a member of the public to try to interpret radioactivity figures without gaining the requisite background to calculate those figures themselves (you can find it here: http://www.epa.gov/radiation/docs/federal/402-r-99-001.pdf ).
Most people (journalists included!) have little to no frame of reference on the subject of radioactivity, and since fear sells, I’m careful about presenting the facts in a way that isn’t easy to twist towards ulterior motives by quoting out of context. The instinctual fear of anything radioactive (usually combined with a lack of awareness of how common place radioactivity is) leads to people doing things like taking KI pills (with a small risk of anaphylaxis as a side effect) to avoid a dose that poses a much smaller risk, or hiding out in a bunker or basement in the US (and getting a large radon dose) to avoid a microscopic atmospheric dose outside. I try my best to counteract this by making sure I present doses and radioactivity in context folks can understand.
And believe me, I discuss and measure weapons fallout all the time and am well versed in how much radioactivity they put out there. One of my favorite teaching tools for the topic is this video ( https://www.youtube.com/watch?v=LLCF7vPanrY ), though granted the US, UK and Russian detonations after ’63 weren’t atmospheric (though some were cratering), same for mid-way through the 70s for France.
Devlin, thanks for that explanation.
Where would these radiation levels fall on the xkcd radiation chart? (If there is an appropriate comparison, that is.)
http://xkcd.com/radiation/
Ingesting a kilogram of the highest cesium concentrations we’ve seen (0.824 Bq/kg Cs-137 with 0.356 Bq/kg Cs-134, both by fresh weight/wet weight) would result in a committed effective dose equivalent (CEDE) of 1.8 μrem or 0.018 μSv. For ingesting the same ratio of Cs-137/134, that dose conversion factor scales up e.g. 10 kg of tuna at that level would be a CEDE of 18 μrem / 0.18 μSv.
So, to fit it on the XKCD chart, eating ~6 lbs of that tuna would result in a dose from cesium the size of one blue square.
(My calculations were done for a reference person, “Standard Man”, and the figures would be slightly different as age, gender and health vary.)
Actually, low doses of radiation, just a little above the level of natural background radiation, has been shown to be beneficial. It is called Radiation Hormesis…please look it up. On related note, I just read a couple days ago that birds around Chernobyl who have been exposed to higher than natural levels of radiation had increase levels of the antioxidant glutathione in their blood, which protects against the oxidative stress caused by the ionizing radiation. Viva La Evolucion
Thanks!
Yes, it’s ok.
Just how is this is relevant to the low level effects of radioactivity or the work done by scientists, doctors and statisticians in trying to assess same?
Delvan,
Really appreciate you stopping by and taking the time to dialogue in the comment thread.
I was happy to. I generally stay out of comment threads, don’t want to feed the trolls, but this seemed like a tame enough thread. I’m always available by email or phone for questions regardless, they’re both on the press release.