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My biggest issue with the paper is the amount of GMO-crop feeded does not appear to correlate with tumor or death rate. Look back at the tumor graph I posted on the first page, in some cases the number of tumors is greater at 22% GMO feed than 33% GMO feed.
This is their explanation for it
Our data show that, as is often the case for hormonal diseases,
most observed effects in this study were not proportional to the
dose of the treatment (GM maize with and without R application;
R alone), non-monotonic and with a threshold effect (Vandenberg
et al., 2012). Similar degrees of pathological symptoms were noticed
in this study to occur from the lowest to the highest doses
suggesting a threshold effect. This corresponds to levels likely to
arise from consumption or environmental exposure, such as either
11% GM maize in food, or 50 ng/L of glyphosate in R-formulation as
can be found in some contaminated drinking tap waters, and
which fall within authorized limits.
It's not my field so I can't even tell how valid that is.
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On September 20 2012 11:05 Klogon wrote:
For things like this, its best to trust the thousands of science professionals who actually know what they are talking about to be the whistle blower. Just being a google-master will not give you any clear answers for something so complicated.
Well put. I think the best thing to do here is to delay our judgment and wait for a more information on this matter, if there is any to come.
This has no bearing on the results, but in general Monsanto has an extremely, extremely poor reputation, especially because of Roundup. The company is responsible for some of the most flagrant environmental contamination as a result their products, which oftentimes have appallingly negative effects on ecosystems :/
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I struggled to understand how Roundup, and NK603 Maize NEVER exposed to Roundup, could possibly produce similar effects in similar levels. This line struck me as a possible explanation:
"The researchers hypothesize that the reason why NK603 GM maize, NK603 sprayed with Roundup, and Roundup on its own, all produced very similar negative health outcomes, is that both the GM maize and the weedkiller Roundup "may cause hormonal disturbances in the same biochemical and physiological pathway."
This is supported by the CERA's GM Crop Database entry on NK603, which describes the other changes to the plant caused by the inserted genes, such as increased production of a number of amino acids and other organic compounds.
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http://www.reuters.com/article/2012/09/19/us-gmcrops-safety-idUSBRE88I0L020120919
The study had too small a sample size and Seralini has made his career off of writing anti-GM literature. Profoundly flawed study on a subject where there have already been 100s of studies performed. No blind testing, no description of the methodology in the controls, and non conclusive results.
Sounds like a nice piece of anti-GM propaganda with no real scientific merit.
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Ohhhhhh, that is an pretty interesting thought. I hope they do a follow-up study on the biochemistry pathway even though that is probably a much harder thing to characterize.
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If anyone thinks something should be added to the OP, PM me and I'll do that tomorrow.
I will however not post more newspaper articles nor random opinions. I will post sourced facts, however.
Note that the quoted article in the OP is there for those who want an oversight of the problem and comes from an anti-gmo website, any further reading should be done in the paper itself.
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Okay, so I read the whole paper, courtesy of AUGcodon (start, if you know what I mean). I'll present my interpretation of the paper as unbiased as I can possibly get:
Figures:
Figure 1:
They looked at the lifespan of the mice and the causes of death. It’s pretty similar across the board. The authors nitpicked at a few cases where the Roundup-treated mice developed some problems relative to control, but it’s not noteworthy at all. When you’re looking at populations, 1 or 2 outliers hardly matter; the overall trend matters more. Problem is that their population size is hilariously small (10). Females got more mammary tumors… no shit Sherlock.
Figure 2:
They looked at tumor sizes. The females had tumors that were big.. really big that it caused obvious problems. Untreated controls appear to have smaller tumors, but by a small margin except for 1 group. No statistics done though.. no way to get anything with such a small sample size so we don’t even know if that difference is statistically significant.
Figure 3:
Gross pictures of tumors, tumors everywhere. While they claim that this is the trend observed, it could also have been a deliberate selection of pictures in order to justify the trend they want to observe. They did do some quantification in Table 2 and it does indeed seem like the Roundup-treated rats have more tumors though. More elaboration below.
Figure 4:
A pretty useless picture, trying to show how bad the cancer can get. It really contributes nothing to the rest of the article, no point commenting more.
Figure 5:
They claim to show that the physiological parameters are similar between groups. Why do I use the phrase “claim to”? Because their graphs make totally no sense. They don’t show which groups are getting compared, nor any biologically relevant numbers, just some really weird coefficients. Figure 5B is a bigger offender; this time they look at individual parameters and can’t even label the Y axis in an easily-understood manner. All I can decipher is that controls are different from treated rats. The authors claimed that they were statistically significant, but I shall not go into a long tangent about statistical manipulation, because this figure reeks of that. Also, the first time I’m seeing error bars in this paper. Too bad it has no meaning at all..
Others:
Problems with methods:
The strain of rat used is particularly susceptible to mammary tumors, which is what the researchers found. One source is found here (http://jnci.oxfordjournals.org/content/27/5/1037.abstract). They did find many other tumors, but again no statistics. I have a concern that they could have been biased when examining the rats (more observant for tumors in the strains that they want them to appear in), but let’s hope that they were unbiased, or at least took some steps to make the examination unbiased.
Problems with statistics:
Each group has only 10 animals (100 of each gender, divided into 10 groups). That’s way too little for statistical analysis. You need a lot more to establish any statistical significance from the results. Anyway, from the graphs, there’s no significance at all.
In conclusion:
Basically, the paper states that the survival of the treated and control rats are similar, although the treated rats have a non-statistically significant increased tumor incidence. The biggest flaw of this paper is really the number of rats per group; 10 is wayyy to little. 50 would be good, 100 would make for convincing statistics. The last figure was really digging deep for something to comment on, but it’s really a waste of space. All in all, they made a point, but they did not prove it beyond reasonable doubt.
Unrelated:
You’re not supposed to house rats in cages alone. They’re supposed to be socially housed, according to IACUC (Institutional Animal Care and Use Committee) guidelines.
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Thanks Heh, nice analysis and I can vouch for him as a student who does research ^^
You really went through that pretty well yo! Definitely quite a fishy paper...random news sites, let alone other research groups are already questioning it, and seriously, it will most likely get ripped apart...
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Common sense says don't spray chemicals on your food.
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Sure, but usually you will have little to no control over whether the food you buy in the supermarket has had chemicals sprayed. Obviously the preferable thing to do is have an integrated pest management system, but oftentimes this is difficult to implement and many farmers just stick with using pesticides or herbicides. Supposedly said substances are used in safe amounts and are regulated, so news/reports like these are worrisome for people.
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On September 20 2012 08:20 sevencck wrote:
This is published in a decent journal, I can access the journal article because I'm at a university. This passed peer review, it must have some merit.
You obviously haven't read enough paper.
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Aotearoa39261 Posts
On September 20 2012 11:35 GreenManalishi wrote:http://www.reuters.com/article/2012/09/19/us-gmcrops-safety-idUSBRE88I0L020120919The study had too small a sample size and Seralini has made his career off of writing anti-GM literature. Profoundly flawed study on a subject where there have already been 100s of studies performed. No blind testing, no description of the methodology in the controls, and non conclusive results. Sounds like a nice piece of anti-GM propaganda with no real scientific merit.
+ Heh_'s analysis is enough for me to close this thread.
I'm happy for a new thread to be made on the subject, but the OP has to be more balanced than it is currently.
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EPT
