(UPDATE 6/25/2013) A graduate student working under Dr. Otaki sent me a huffy tweet, in which she said, "That comment doesn't mean that professor is right. We have Q&A page that proves him wrong. Here's the link: http://t.co/TrSDu5QvZy" It's in Japanese. From all I can tell, their rebuttal is "Trust us."
Quickly checking her tweets, I'm afraid she is in an "echo chamber" - position for an activist and not a researcher.
Does being published on Scientific Reports magazine mean it is correct and right?
Remember the blue butterflies in Tohoku region that were supposedly irreparably damaged and mutated by the radiation from the Fukushima I Nuclear Power Plant accident? Or so it is claimed by researchers at University of the Ryukyus whose paper was published in Scientific Reports magazine in August last year?
There were several retweets on my twitter page (like this one) about this old story yesterday, with a new incredible twist.
According to people who tweet and retweet, the researchers who did this research telling the world how contaminated Fukushima was and how dangerous the radiation levels were in Fukushima to cause such mutations (never mind that the same researchers had attributed the mutation to temperature before the accident, as none of these people bother to know the details), and what's more, whose paper has been accepted by a peer-reviewed magazine (true) called Nature (not true, just the same publisher), have just been denied funding for their work!
See how the government censors the truth! Let's all donate money to them, so that they can continue this invaluable research!
Having the research funding cut in the middle of a school year is itself incredible (it usually happens at the end of the school year for the funding for the next year, i.e. March), but people are totally buying the story.
Why? Because one of TV Asahi's programs (the same one that didn't know Reactor 4 building was systematically dismantled) reported on the research on May 30 this year after one of the TV stations in Germany (ARD.de) featured it in October last year.
For some reason, anything that comes from Germany is received in Japan as more credible than those coming from other foreign sources like France or the US. BBC is considered more credible than others but less so than Germany's media. Asahi simply uncritically parroted what the researchers said (or what the German TV said the researcher said). So now, for a lot of people in Japan, it is proven as a fact (as accepted by a peer-review magazine, no less) that these butterflies mutated because of the low-level radiation from the Fukushima I Nuke Plant accident. "In such a short time! What will happen to people in Fukushima! I'm scared!" is a typical tweet in reaction.
As far as I was concerned in August last year, the paper was a redux of the Sokal Affair.
On re-visiting the link to their paper, I noticed there was a comment attached to the paper. When I wrote the initial post on the subject on August 17, 2012, the comment was not there.
The comment was by Dr. Timothy J. Jorgensen, on August 21, 2012. Dr. Jorgensen is associate professor of Health Physics and Radiation Protection Program at Georgetown University, and he shredded the paper to pieces.
From the comment section of the paper "The biological impacts of the Fukushima nuclear accident on the pale grass blue butterfly", Scientific Reports (emphasis is mine):
Dear Scientific Reports editors:
The recent article, The biological impacts of the Fukushima nuclear accident on the pale grass blue butterfly [Sci. Rep. 2, 570; DOI:10.1038/srep00570 (2012)], has a number of scientific problems that raise serious doubts about the validity of its findings and the conclusions that can be drawn about low dose radiation effects on insects or humans. Although these scientific issues are too numerous to be addressed here, three main problems need to be mentioned for the record.
A major finding of the study is that forewing size was inversely correlated with distance from Fukushima, resulting in the conclusion that radiation from Fukushima had stunted forewing development. However, the more distant butterfly sampling sites were all progressively further south of Fukushima, so that latitude was also changing with the distance. This is a problem because it is well established that the forewing size of a number of insect species is dependent upon the latitude of their microhabitat. This has been extensively studied both in fruit flies (Drosophila subobscura) and butterflies (Pararge aeberia), and the magnitude of the forewing changes found in this study is comparable to these known latitudinal determinants on forewing anatomy (1, 2). The potential latitudinal influences on forewing size were completely ignored in this study. Had the data been adjusted for sampling site latitude, it is likely there would have been no significant forewing findings to report.
The second major problem is that the decreased butterfly survival rates reported to be associated with proximity to Fukushima are claimed to be reproducible in the laboratory with external beam irradiation. This claim stretches credulity since it has long been established that insects, including butterflies (Order: Lepidoptera), are resistant to radiation effects. It takes an average dose of 10,000 mSv to kill a Lepidoptera cell (3), and it requires an average dose of 1,300 mSv to Lepidoptera eggs to reduce their hatch rate by 50% (4). Larval, pupal, and adult forms of Lepidoptera are even more radioresistant (5). The concept that the low environmental radiation exposures (<15 mSv per year) that are being attributed to the Fukushima accident could be killing off butterflies, or any other insect species, is simply not credible. It should further be noted the external radiation doses that were used to reproduce the results from field-collected individuals were 00 times higher than any radiation doses in the field that could possibly be attributed to Fukushima. Thus, it can even be seen from the investigators' own laboratory experimental data that no measurable killing would be expected at the radiation doses that were encountered in the field.
The third major problem regards the time to eclosion (emergence of an adult insect from a pupa). Eclosion times were claimed to be associated with proximity to Fukushima. Yet irradiation has been employed as a pest control measure for a number of insect species for decades (6), and the effects of radiation on various insect biological endpoints have already been well characterized. It typically takes as much as 30,000 mSv of Lepidoptera egg irradiation to extend eclosion times by the 4 to 5 days reported in this study, and similarly high doses are required when irradiation is done in the larval stage (5). It is, therefore, astounding that effects on eclosion of a similar magnitude can be seen at radiation doses that are just a few fold above natural background doses. So the claim that eclosion times were extended due to these environmental radiation exposures is also incredible when compared to the literature. Perhaps it is more plausible that eclosion time of the pale grass blue butterfly, like forewing size, might also be related to microhabitat latitude or temperature. [Average daily temperatures differ by as much as 9 degrees Celsius between Fukushima and Tokyo during April (hatching season).]
There are other inferences from this study's findings that counter established radiation biology tenets, including the notion that radiation can target specific developmental genes for mutation simultaneously in multiple individuals, which is what would be required to explain much of the findings reported in the study. Further, the field dosimetry procedures reported in the methods were inadequate to the task at hand. Namely, it should have been possible to actually measure the 137Cs contamination in the environment, which would have allowed an estimation of the component of the environmental radiation dose that could actually be attributed to the Fukushima accident. Moreover, the investigators should have applied the same sampling and statistical rigor to their environmental radiation dosimetry measurements as they did for their biological endpoints. Had they adequately captured this additional source of variability, which would have likely been substantial, it is doubtful that they would have produced the same findings.
In conclusion, the results reported in this study should be considered highly suspect due to both their internal inconsistencies and their incompatibility with earlier and more comprehensive radiation biology research on insects. The study's central assertion is that 'artificial radionuclides from the Fukushima Nuclear Power Plant caused physiological and genetic damage to [the pale grass blue butterfly]'. This statement is incredulous and goes well beyond anything that the study data can actually substantiate. Therefore, this study's sensational claims should not be used to scare the local population into the erroneous conclusion that their exposures to these relatively low environmental radiation doses put them at significant health risk.
Timothy J. Jorgensen, PhD, MPH
Department of Radiation Medicine and the Health Physics Program
1. Gilchrest GW, Huey RB, Serra L. Rapid evolution of wing size clines in Drosophila subobscura. Genetica 2001;112:13.
2. Vandewoestijne S, Van Dyck H. Flight morphology along latitudinal gradient in a butterfly: do geographic clines differ between agricultural and woodland landscapes? Ecography 2011;34:13.
3. Koval TM. Intrinsic resistance to the lethal effects of x-irradiation in insect and arachnid cells. Proc Natl Acad Sci U S A 1983;80(15):4752-5.
4. Chanu OP, Ibotombi N. Effect of 60Co gamma radiation on eggs of tasar silkworm, Antheraea pryoylei (Lepidoptera). J. Exp. Sciences 2011;2:5.
5. Ayvaz A, Albayrak S, Karaborklu S. Gamma radiation sensitivity of the eggs, larvae and pupae of Indian meal moth Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae). Pest Manag Sci 2008;64(5):505-12.
6. Robinson AS. Mutations and their use in insect control. Mutat Res 2002;511(2):113-32.
Scientific Reports is an open-access magazine that accepts comments. There is no response to Dr. Jorgensen's comment from the researchers at University of the Ryukyus.
I tweeted this comment section. Reaction from scientific researchers and doctors, who read the comment, was "I see, this is how an open-access paper is reviewed and criticized. What a wonderful thing for the University of the Rukyus' researchers", or "My goodness, what a brutal rebuttal..." Reaction from some non-researchers was "Nature magazine is a pro-nuke outfit!" and end of story.