4

It seems plausible that increased radiation exposure could negatively impact the health of these populations.

  • cancer patients currently on a chemoradiation regime
  • cancer survivors who are at-risk from radiation exposure
  • those with cancer risk, which may be at-risk from radiation exposure

This professor says:

The concern is that not any one person eating one tuna is gonna have a problem, but that over large numbers of people, the small increase in radiation will produce a small increase in cancer risks.

Not all fish or sea-food products (e.g. kelp) would be involved - only those with increased bio-accumulation of radioactive particles.

Some articles state that fish caught near Fukushima (from var. time periods) is not safe. Other statements say that pacific ocean fish "pose no risk to people" without citing levels of potential exposure in relationship to safety regulations.

How does a increase in risk to large numbers not impact the individuals risk? Are there factors that will increase the risk to an individual eating these fish?

  • I feel like all of you people have tried to simplify the question without providing justification for the simplifications. This is likely a complex matter that affects very specific populations, while others are unlikely to experience dangers that fall outside of regulations – New Alexandria Dec 3 '13 at 21:46
  • 1
    @NewAlexandria -Skeptics SE is not for requesting original research. We investigate claims of fact made by notable people. The professor in the first claim was a perfect choice which is why I limited the question to that link. Your second link basically answers the question you are asking. I do not know what you are expecting from here but I suspect it is off topic. You could problably make 20 different questions just off of the information in your links. – Chad Dec 3 '13 at 21:51
  • 1
    @NewAlexandria Thanks for including the quote. That is the only part of this question that is on topic. This question would be improved by removing the rest of the question. But, since you reverted my edit last time, I'll leave that to you. – user5582 Dec 3 '13 at 21:54
  • 2
    "over large numbers of people, the small increase in radiation will produce a small increase in cancer risks." The Linear No Threshold model says this is true, but its also true (and a larger-but-still-microscopic risk) for bananas, brazil nuts, and indeed the C14 present in all sugars. Doing the maths allows one to make silly predictions like the ones here. Note for comparison, alcohol causes about 20,000 annual cancer deaths in the USA. – Ken Y-N Dec 4 '13 at 0:15
  • 2
    @KenY-N: Why don't you expand that comment into a real answer? (You should include a better explanation of why you think that prediction is silly, because you seem to beg the question there.) – Oddthinking Dec 4 '13 at 1:10
7

I'll skip the "seems plausible" conjecture, and focus on the professor who says:

The concern is that not any one person eating one tuna is gonna have a problem, but that over large numbers of people, the small increase in radiation will produce a small increase in cancer risks.

If we look at the Linear No-Threshold model, what the professor says is absolutely true. There are two other main models, the Threshold model that says up to a certain level radiation is benign, and the Radiation Hormesis model that says up to a certain level radiation is actually beneficial. Thus, the LNT is obviously the more conservative of the three. As far as I am aware, the other two models are more favoured scientifically and LNT is just a compromise. Note, however, that UNSCEAR says this:

Due to the great uncertainties in risk estimates at very low doses, UNSCEAR does not recommend multiplying very low doses by large numbers of individuals to estimate numbers of radiation-induced health effects within a population exposed to incremental doses at levels equivalent to or lower than natural background levels.

This is what the professor is doing. Looking at data from east Pacific tuna presented here, we see:

In bluefin tuna caught off San Diego, the total radioactive cesium levels were 10 becquerels, only three percent above radiation levels from naturally occurring potassium-40, and far below safe-consumption levels set by the United States and Japanese governments.

I shall assume they mean 10 Bq/kg.

A single banana, by comparison, has 15 becquerels of potassium-40, or, given a 150 gramme banana, 100 Bq/kg. Therefore we are looking at less than a tenth of the effect (or indeed 40% of the 25 Bq/kg from the C14 in the sugars in a banana). However, I have seen it argued that (a) the body has evolved to handle natural radiation (now that would be a good question for here!) and (b) it bio-accumulates, unlike K40 and C14.

Therefore, I conclude that Professor Daniel Hirsch (ad hom: a politics lecturer and anti-nuclear campaigner) is correct in what he says, but he goes against the advice of UNSCEAR to produce his conclusion.

  • And for god's sake, put that banana down before you doom everyone in the house! – Shadur Dec 4 '13 at 12:38
  • This does not answer the question, which regards at-risk populations. By skipping the main part of the question, you have answered someone else's question - not this one. I consider your answer a comment, or an answer to a different question. – New Alexandria Dec 4 '13 at 14:34
  • To be extra-clear, the professor that's being quoted was not speaking about at-risk populations. – New Alexandria Dec 4 '13 at 14:35
  • 2
    @NewAlexandria If the referenced quote isn't about at-risk populations, then the question isn't either: the subject of the question and the answer is the quoted reference. To ask instead about at-risk populations, you must reference a claim about about at-risk populations: a reference which could say either that they are, or that they are not, at risk from such increases. FAQ: Must all questions be notable? – ChrisW Dec 4 '13 at 14:54
  • @Shadur - Its not going to doom everyone just 1 in 500M just hope that 1 is not in your house :p – Chad Dec 4 '13 at 15:02

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .