Tuesday, September 25, 2012

Did the rats in the GM corn study drink their water from BPA bottles?

**Updated 90/30/12 at the end of the post.

In my previous post, I noted that the researchers in the now-infamous GM corn/rat study had used polycarbonate cages, rather a no-no when you're doing work with compounds you suspect of being endocrine disruptors. Why? Because polycarbonate plastic leaches bisphenol A (BPA). As it happens, the strain of rats used in this study takes up BPA via the skin quite easily, and BPA in male rats is linked to mammary tumors, which male rats in this study developed. 

As this slide show here indicates (screenshot below), these researchers certainly were aware that they were dealing with a study in the endocrine-disruption context [viewing requires QuickTime], yet they did not take steps to prevent this exposure. Another issue that  experts in this field argue requires special care in such studies (update: despite the broad nature of what's written at that link, according to at least on of the authors, the real concern is only with studies of BPA) that authors appear to have overlooked is using animal feed that could serve as a source of estrogenic compounds. And finally, the biggest no-no of all? Using polycarbonate water bottles, which are known to leach BPA.


When writing the earlier post, I had only information about the cages and the cage supplier the group used. Today, thanks to a Tweet, I got to watch a video that shows the water bottles this research group used, up close and personal. As I'd noted yesterday on this post by Orac at Respectful Insolence, my observations about the polycarbonate cages and the potential influence of bisphenol A leaching were speculative, but certainly less so than the authors' self-debunked hypothesis for the GM corn they used. In that comment, I added, 
if the water bottles were not glass … then what I wrote moves beyond the speculative.
Here are some screenshots from videos that this group has posted to YouTube to promote--surprise!--the anti-GMO movie, Tous Cobayes [All Guinea Pigs]. It starts out with hilariously silly scenes of slow-walking people in scrubs, footies, and face masks that I think were intended to build suspense but that really reflect what any animal tech or researcher has to do every day when entering an animal care facility. It also happens to feature several close-up views of the water bottles this group used to give their 200 study rats access to water for two years. Here are the screenshots.




As you can see, it's a rather unusual-looking bottle, not one I've encountered before in my own work with rodents, using glass bottles. But it's difficult--for me, at least--to tell if it's plastic or glass based on these views. So, I looked for the supplier.

I found the supplier here. It happens to be Genestil, the same France-based supplier of the polycarbonate cages the GM/rat researchers housed those rats in for two years. 
And according to this product description for "biberons" [bottles] that this group's cage supplier offers, the bottle in question, based on a visual match of its unusual three-tiered style, is a 750-ml version that is made of macrolon, also known as ... polycarbonate [PDF]. I don't find glass bottles in their catalog.
If that is true, then this study that the authors knew before the fact likely would involve endocrine disruption subjected 200 rats to two years of living in polycarbonate cages leaching the known endocrine disruptor bisphenol A and sucking down water from bottles leaching the same. For two years. If it is true, it's no wonder their control values overlapped with other values and their data made no sense, even with the Roundup treatments in water.

These are "ifs," I know. And even without these factors, the study falls to the ground for many, many other reasons. But frankly, I'm upset with these researchers. In their zeal, they have treated scientists and their other readers with an off-handed sort of arrogance in the way they obscured their data, tried to manipulate the news media (succeeding, by the way), and concealed conflicts of interest (book! movie! official anti-GMO activism!), apparently based on the assumption that all of us--critics and fans alike--are a bunch of fools who won't see through their oh-so-clever sleights of hand. Fooling people once or twice or three times? That's one thing. But if they wasted 200 helpless rats bursting with tumors (where are those control tumors?) in their crusade and their very basic animal husbandry was an experimental confounder that makes their crazy results totally useless? The rats don't get to choose here. 

I have emailed the contact email on the GM/rat study asking two things. The first is, Was their supplier for the water bottles the same as that for the cages? The second is, Were the bottles they used glass ... or plastic?
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****In an email exchange with a well-known EDC researcher, I've been told that the BPA exposure routes via polycarbonate cages and/or bottles is of specific concern to BPA-related studies only. I don't understand why that is, given the confounding potential of BPA or any other EDC compound in a study involving EDCs, but that's what this investigator said. All that time we spent looking for glassware instead of polycarbonate products, wasted!  Not really. I still argue that in such studies, we need to be as careful as possible to exclude potentially confounding exposures.

4 comments:

  1. This reminds me of when I was evaluating strains of nematodes with GFP tags on oxidative stress pathway genes. I was trying to see if I could detect (and hopefully quantify) copper-induced oxidative stress by looking at GFP expression that would make the worms glow under the microscope if they were fighting oxidative stress.

    But all my worms, control or treatment, were glowing like blacklight posters in a hippie den. The worms didn't want to crawl off the pick when I moved them to a new agar plate, which I didn't realize was odd until I mentioned it to the prof next door who had worked with nematodes for a long time. He offered me some high-purity agar to see if this made a difference, and it did.

    It turned out the cheap grade of agar I used was allowed to contain heavy metals or organic contaminants. (Bad Fisher! Bad!) So at that point, I had a reason to request the good agar that cost about 3x as much.

    Unfortunately, for other reasons I don't really remember, those strains didn't work out. But if I hadn't gone through that step of eliminating bad culture media before I planned my project, my results would've been total nonsense.

    The GMO/Roundup study is a total waste of rat lives and grant money. I don't know how they got the experiments approved and the paper accepted. This is the kind of study that led my mother to dismiss carcinogen testing as "Lab rats get cancer no matter what you do. I'm not a lab rat, so I'm not worried."

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  2. I strongly agree with both of you on the crual and stupid waste of 200 rodent's lives. Animal testing should be confined to live-saving research - and good science.

    (No exceptions. One could think sexually frustrating male fruitflies is crual and pointless : but it might give us a clue on how to deal with a major health issue.
    http://www.nature.com/news/rejected-flies-turn-to-booze-1.10227 )

    I'm also more and more upset with those "scientists". Speaking of CoI, there might be more than just promoting a movie and a book. (actually, two books, the second one is by Corinne Lepage, french politician and honorary chairman of Seralini's association.)

    This research was funded and/or supported by two of France's major retailers corporations : Auchan and Carrefour. (http://www.bioportfolio.com/news/article/1176418/Auchan-And-Carrefour-Financed-Criigen-Studies-On-Gmos.html - Dubious link, but I wanted to post something in English. Every french mainstream media confirms this fact ( http://www.lexpress.fr/actualite/sciences/sante/auchan-et-carrefour-ont-aide-a-financer-l-etude-sur-les-ogm_1164587.html )

    Auchan's co-founder is a long-time opponent of GMO's. (Sorry, it's written in French :
    (http://unepetitegraineverte.over-blog.org/article-19217831.html )
    It's not clear whether he's opposed to GMO because they might be harmful to our health or to his business. Core job of a retailer is downgrading the prices of it's providers. He seems to be very afraid that Monsanto's monopoly might "raise the costs" and "starve the world." Don't know if we should laugh or cry - probably both.

    Carrefour, a very, very powerfull corporation, worldwide #2 after WalMart, ran an ad campaign two years ago, promoting their brand new "no GMO" labelling.
    ( http://www.couleurgeek.fr/20391-publicite-carrefour-nourri-sans-ogm-300-produits-concernes/20101026.html )

    I'm not a conspirationist, even if I tend to see the Evil's hand every time power, money and human beings are involved. BUT I WANT TO KNOW WHY 200 RATS DIED. WHY ???!!!!


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  3. Why did 400 rats die in this monstrosity which proved Nothing and no one complained?

    Results of a 90-day safety assurance study with rats fed grain
    from corn rootworm-protected corn
    B. Hammond a,*, J. Lemen a, R. Dudek a, D. Ward a, C. Jiang a, M. Nemeth a, J. Burns b
    a Monsanto Company, 800 North Lindbergh Blvd., St Louis, MO 63167, United States
    b Covance Laboratories, Inc., 9200 Leesburg Pike, Vienna, VA 22182-1699, United States
    Received 1 June 2005; accepted 22 June 2005
    Abstract
    The results of a 90-day rat feeding study with YieldGard (YieldGard Rootworm Corn is a registered trademark of Monsanto
    Technology, LLC.) Rootworm corn (MON 863) grain that is protected against feeding damage caused by corn rootworm larvae are
    presented. Corn rootworm-protection was accomplished through the introduction of a cry3Bb1 coding sequence into the corn genome
    for in planta production of a modified Cry3Bb1 protein from Bacillus thuringiensis. Grain from MON 863 and its near isogenic
    control were separately formulated into rodent diets at levels of 11% and 33% (w/w) by Purina Mills, Inc. Additionally, six groups of
    rats were fed diets containing grain from different conventional (non-biotechnology-derived) reference varieties. The responses of
    rats fed diets containing MON 863 were compared to those of rats fed grain from conventional corn varieties. All diets were nutritionally
    balanced and conformed to Purina Mills, Inc. specifications for Certified LabDiet 5002. There were a total of 400 rats in the
    study divided into 10 groups of 20 rats/sex/group. Overall health, body weight gain, food consumption, clinical pathology parameters
    (hematology, blood chemistry, urinalysis), organ weights, gross and microscopic appearance of tissues were comparable
    between groups fed diets containing MON 863 and conventional corn varieties. This study complements extensive agronomic, compositional
    and farm animal feeding studies with MON 863 grain, confirming that it is as safe and nutritious as existing conventional
    corn varieties.
    2005 Elsevier

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    Replies
    1. I can't say if anyone complained or not as that was published seven years ago, before this wonderful world of social media had really gotten off the ground and made all of this information so much more readily accessible. That said, based on the abstract (the study itself is paywalled), they were doing a pretty standard study of the sort most people complain don't exist to establish substantial equivalence and/or in the name of the precautionary principle. Not sure how the study "proved nothing"? It can't be both ways--a demand for studies of safety and then a complaint if the studies don't find something wrong.

      Also, a quick-n-dirty google search turned up some complaints about this one, but maybe they're not from the right people?

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