Why its no longer safe to eat tuna or salmon
For the folks not aware of the concepts of bioaccumulation and biomaginification…
Bioaccumulation refers to the accumulation of substances, such as pesticides, or other organic chemicals in an organism. Bioaccumulation occurs when an organism absorbs a toxic substance at a rate greater than that at which the substance is lost. Thus, the longer the biological half-life of the substance the greater the risk of chronic poisoning, even if environmental levels of the toxin are not very high.
Biological magnification often refers to the process whereby certain substances such as pesticides or heavy metals move up the food chain, work their way into rivers or lakes, and are eaten by aquatic organisms such as fish, which in turn are eaten by large birds, animals or humans.
Caesium-137 (137
55Cs, Cs-137), cesium-137, or radiocaesium, is a radioactive isotope of caesium which is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons. It is among the most problematic of the short-to-medium-lifetime fission products because it easily moves and spreads in nature due to the high water solubility of caesium’s most common chemical compounds, which are salts.
-
Fri, Jan 31, 2014 - 10:39pm
#2Wildlife Tracker
Status Silver Member (Offline)
Joined: Jan 14 2012
Posts: 405
count placeholder0smaller diagram and link
Wildlife Tracker,
This is interesting, but literally *none* of the links provided were sourced back to actual, rigorous science.
While that certainly doesn't mean there is no risk, or that this event is not happening, it does not provide the scientific authority to make the claims it makes.
The largest oversight is bio-accumulation. When perusing the articles in the original links, there was nothing in there at all regarding bio-accumulation and it's impacts on the marine life in question. Without that thesis supported, the rest of this article is simply relying on a network of hyperlinks to other non-scientific journals who are using similarly non-scientific suppositions.
Again, I'm not trying to say that this isn't something that requires investigation, but the headline and information contained within this article is facile and misleading. The subject of radiation is always tricky since Americans are raised on a steady diet of Spiderman, the Hulk and other wide-eyed sci-fi that has no grounding (at all) in the realities of how radiation interacts with biological organisms.
Hopefully someone around here can unravel this a bit further, and maybe even support an argument with some science.
Cheers,
Aaron
-
Sun, Feb 02, 2014 - 12:11am
#4Wildlife Tracker
Status Silver Member (Offline)
Joined: Jan 14 2012
Posts: 405
count placeholder0article
I think I just copied and pasted one of the first articles I googled suggesting that cesium is problem that should not be ignore, i was tired after I made the diagram. I understand it was silly of me to post that and I wish I could delete it, but I can't.
Fortunately, I understand the science well and I hope I can clarify your questions.
The diagram was something I put together to demonstrate the concept of biomagnification through the food web with species I identified to be the likely vector species that would transfer cesium 137 up the food chain into those two valuable food resources. I also provided basic definitions that I found on wikipedia, but you can find those definitions anywhere. Quickly google search DDT, mercury, and PCBs you will find countless articles backed by scientific studies regarding the bioaccumulation of non-digestable elements, chemicals, etc.
Rachel Carson wrote a famous book called silent spring that discussed why eagles and falcon's were dying near agricultural areas from DDT and the dangers of non-digestable compounds and elements as they accumulate up the food chain.
The dangers of cesium 137 accumulation in the body is studied across the planet (http://scholar.google.com/scholar?hl=en&q=bioaccumulation+cesium+137&btnG=&as_sdt=1%2C22&as_sdtp=), but never has there been such a hotspot of cesium 137 entering the ocean (http://www.nuc.berkeley.edu/forum/218/nuclear-expert-fukushima-spent-fuel-has-85-times-more-cesium-released-chernobyl-%E2%80%94-%E2%80%9Cit-woul), everyday, non-stop, over the last couple years and with no timeframe for when it will stop. Based on the fact that the aquifer underneath Fukushima will soon overflow with nuclear contaminants, the problem is highly likely to escalate. http://www.bbc.co.uk/news/world-europe-23584008
Cesium 137 in high concentrations is very deadly (http://large.stanford.edu/courses/2012/ph241/wessells1/) and is very easy to accumulate in the body
Here is a great article I just found discussing the same dangers as I mentioned…http://www.whoi.edu/oceanus/feature/how-is-fukushimas-fallout-affecting-marine-life
I hope that helps
-
Mon, Feb 03, 2014 - 12:49pm
#5robie robinson
Status Gold Member (Offline)
Joined: Aug 25 2009
Posts: 1138
count placeholder0it helped me
understand why i should eat albacore tuna (shorter life and less time to accumulate) and not bluefin. did i get that right?
-
Mon, Feb 03, 2014 - 09:53pm
#6Wildlife Tracker
Status Silver Member (Offline)
Joined: Jan 14 2012
Posts: 405
count placeholder0If you choose to eat Pacific fish…
You will want to eat seafood lower on the trophic pyramid. Even though albacore has a shorter life span, it still will have much higher concentrations (in theory) than a smaller fish because it probably will rely more heavily on getting its energy from secondary consumers rather than primary consumers (the lower down the pyramid, the lower the accumulation rate). Therefore, it's much safer to eat a fish that relies on plankton as a food source, rather than mid-sized fish.
Tuna and salmon might be okay to eat once in a while, but it's important to recognize this as a threat to your own personal health and the health of the larger public, especially going forward. Governments around the world do not seem to give a crap about this potential threat. Fukushima has a lot of potential to really do some damage to the marine-life in the Pacific over the next 20-30 years, especially in combination with over-fishing (trawling practices), plastics, and other pollution.
While I agree with the theoretical concern, at least so far, the concerns appear unjustified:
http://newswatch.nationalgeographic.com/2013/09/11/fukushima-fallout-not-affecting-u-s-caught-fish/
So eat salmon, drink, and be merry today – because one day the fears of contamination may come true!
-
Tue, Feb 04, 2014 - 09:41pm
#8Wildlife Tracker
Status Silver Member (Offline)
Joined: Jan 14 2012
Posts: 405
count placeholder0Not totally “theoretical”
Cesium found in plankton
Also, I have not read about a study on tuna since 2011/2012. It's 2014 now. Maybe they are out there, but I don't know.
Fri, Jan 31, 2014 - 03:35pm
#1Why its no longer safe to eat tuna or salmon