Saturday, September 7, 2013

GMOs and Reproductive Problems

This week, I resume the task of reviewing the health impact of GMOs, as outlined on the Institute for Responsible Technology's webpage. As a reminder, I have yet to find a single item that is a true health concern from their page, yet it remains one of the most highly cited anti-GMO pages. So, I must march-on!!

This week, I'm going to tackle the section entitled "GMOs, reproductive problems, and infant mortality". We'll go through these statement by statement.
  • More than half the babies of mother rats fed GM soy died within three weeks. This statement is attached to three references. The first is from a talk or abstract at a conference, the second is from a news article in a Russian paper, and the third is a reference to preliminary (i.e unpublished) studies. As outlined in my explanation on types of references, none of these are vetted, peer reviewed sources of information. All three are from the same author, I.V Ermakova, so I decided to check pubmed to see her publications. There are 33 publications by the author and only one was about GMOs. The publication in question was a letter published in Nature Biotechnology (note that it was not a scientific paper). And then I started reading it... Holy GM controversies, Batman!! So here's the TMZ scoop: in 2007, Nature Biotechnology interviewed Dr Ermakova. She had reported that feeding Round-up Ready GM soy beans to rats leads to pups with low survival rates or stunted growth. The report had been widely circulated in the press, leading to calls for independent studies of GM crops. However, two years later (in 2007), Dr Ermakova's study had not been published (and based on my pubmed search, it still isn't published). So Nature Biotechnology (a very high impact journal) decided to do an interview with Dr Ermakova to ask for a detailed account of her work. And then they brought in experts to review the information that she provided, who proceeded to point out all the flaws including:
    • The feed that she used didn't exist. Literally. The author claims that she purchased the soybeans from a company in the Netherlands, but that company had never sold the type of materials she used in her study.
    • The study didn't meet the standard norms for number of animals
    • The author claimed that over one-third of surviving pups born to mothers who were eating GM soy had stunted size and low birth weight. Additionally, she claimed that males have high levels of anxiety and aggression. As if that weren't bad enough, mice who were fed GM soy failed to breed to a second generation. No evidence or data was presented, and Dr Ermakova's description of issues/results do not match with previous reports in the literature which have looked at GM soy beans (last week's blog looked at multi-generational effects of GMOs, if you're interested).
    • The author claimed that 50% of pups died by the end of the 3rd week when fed GM soy, versus 8% in the controls (they actually shared the numbers for mortality). The panel of experts point out that 99.5% of the control rats should survive for the strain being used; since only 92% are surviving, probably something wonky was going on and quite possibly, they just weren't taking good care of their mice. Additionally, no post-mortem examination was performed and no cause of death is given. They state that a 50% pup mortality rate defies credibility and such a strong lethal effect would have never escaped researchers or agricultural agencies (I completely agree!! 50% mortality rate???)
    • The author claimed that 33% of the pups from rats fed GM soy had smaller sizes and lower weights than the controls. The critics point out that more than 90% of the control rats were more than 20% below normal weight, suggesting that they were malnourished or subject to poor environmental conditions.
    • The author concludes that Round-up Ready Soy has a negative influence on the strain of rat used, as well as their offspring, causing high mortality, infertility, decreased weight gain, change in behaviour, and changes in internal organs. The critics conclude that no meaningful conclusions can be drawn because there were so many flaws in the study.
  • One of the more intriguing sections of the interview was when Dr Ermakova was asked why she hadn't yet published her findings. She explained that she had presented her data at several conferences, where she had appealed to scientists to repeat her experiment, which drew the attention of a journalist, and things took off from there.  However, she explained that she was in the process of submitting her finding for publication. The critics rightly point out that if "she had questions about her own results, as she says she did, she should not have devoted so much time to publicizing what are demonstrably flawed studies". Ouch.
  • You'd think that the saga would have ended there. But... no! Dr Ermakova wrote back to Nature Biotechnology to try to polish the turd. That letter is the one article by Dr Ermakova that I was able to find in pubmed on the topic of GMOs. Dr Ermakova basically blamed Nature Biotechnology for misrepresenting her work, for not giving her the chance to defend her responses prior to publishing, and questions why the journal would not publish her paper yet would publish such a long interview and she suggests that perhaps this is due to the "reluctance of the predominantly industry-funded agbiotech community to condone the publication of studies that detail negative effects of GMOs". The letter also includes corrections by Dr Ermakova (such as details on how the rats were raised, etc).
  • The fact remains that 6 years later the study has not been published and has not been reproduced. That says more than a dozen interviews or letters ever could regarding the quality of the study.
There's no doubt that Dr Ermakova felt insulted by what she considered to be mistreatment by the journal. And I can't help but sympethize for her, because some of the comments made by the critics were personal. At one point, the critics actually point out that maybe all the mistakes made were because of the fact that Dr Ermakova didn't have proper training in performing a reproductive toxicological animal study. That's a pretty personal diss. But I don't think that the journal did anything wrong here: the study was making so much ruckus in the news that the editors probably felt compelled to step in to figure out what was going on; yet, at the same time, the study wasn't good enough to publish. So what other options could there have been?

Well, I was going to go through the rest of the reproductive risks, but I think I'll resume next week.

In summary, Dr Ermakova's findings which are plastered all over the interwebs have never been published, most likely due to the quality of the study. Since my legilimency skills are not strong enough to sneak into her mind and see what the study entailed, I must discard references to her "findings".

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