1. Prof Tom Sanders's comment on Seralini's study
2. GMWatch response to Sanders's comment
3. GMWatch profile of Tom Sanders

NOTE: On 19 September Prof Seralini's team published a study that showed a commercialised Monsanto GM maize, as well as tiny amounts of Roundup claimed to be safe, when fed to rats, caused massive tumours and premature death. 

On the same day, a collection of quotes from "experts" was rushed out, all trying to discredit Seralini's study. The source was the Science Media Centre (SMC).

None of these people had analysed Seralini's data (which they did not have access to) or had even thought about the paper for 24 hours before they gave their quotes – the bare minimum for a complex study like Seralini's.

The SMC's misinformation worked: the three critical quotes mentioned by the newswire Reuters about the study (Tom Sanders, Mark Tester, David Spiegelhalter) were all circulated by the Centre.

Below (item 2) we address the arguments in the quote that Prof Tom Sanders, one of the "experts", provided to the media via the SMC (item 1), and give some information about his background (item 3).

More on the SMC:
1. Prof Tom Sanders's comment on Seralini's study

Expert reaction to GM maize causing tumours in rats
Science Media Centre press release
19 Sept 2012

Prof Tom Sanders, Head of the Nutritional Sciences Research Division, King's College London, said:

"Most toxicology studies are terminated at normal lifespan i.e. 2 years. Immortality is not an alternative.

"No food intake data is provided or growth data. This strain of rat is very prone to mammary tumours particularly when food intake is not restricted.

"There is a lack of information on the composition of the diet. One concern is whether there were mycotoxins in the maize meal because of improper storage. Zearalanone is a well know phytoestrogen produced by filamentous fungi that grow on maize.

"The statistical methods are unconventional, there is no clearly defined data analysis plan and probabilities are not adjusted for multiple comparisons."
2. GMWatch response to Sanders's comment
(incorporating comments from scientists:

Sanders's comment that "Most toxicology studies are terminated at normal lifespan i.e. 2 years. Immortality is not an alternative" is baffling, as Seralini too terminated his experiment at 2 years. 

Sanders is incorrect to say that 2 years for a rat is normal lifespan. It corresponds to around 65 years in human terms: (presentation: slides 13-16)
More information:

Sanders's comment that "No food intake data is provided or growth data" is disingenuous. You cannot squash all your data into a peer-reviewed paper. Editors give you a word count. 

The normal response to the absence of a certain piece of information in a paper – a piece of information that is not of central relevance to the study – would be to ask Seralini's team for the information and consider the response, not to throw a hissy fit and throw out the entire paper.

But "experts" recruited to dismiss the inconvenient findings of independent scientists do not behave normally.

Here is that information, which apparently someone did ask for, and got. In Seralini's experiment, the rats had unrestricted access to food and water and there were no differences in consumption or drinking levels between controls and test groups except for the group exposed to the highest Roundup concentration in drinking water. This group of rats drank less water (wouldn't you?).

Sanders's claim that the Sprague-Dawley (SD) strain of rat that Seralini used "is very prone to mammary tumours" backfires on him badly. The SD rat is widely used in toxicological experiments, including in the long-term toxicity and carcinogenicity tests performed by Monsanto on glyphosate to gain the 2002 approval for marketing in the EU. The SD rat was also used in Monsanto's 90-day feeding trial on this same maize, NK603, that led to its approval in the EU.

So if Seralini used "the wrong rat", so does industry, and we should throw out the hundreds of industry studies on chemicals and GMOs that have used the SD rat. That means goodbye glyphosate, thousands of chemicals, and many GM foods.

And data from the Ramazzini Institute in Italy shows that far from being unusually "prone" to tumours, the SD rat is an excellent model for human carcinogenicity and is about as prone to tumours, both "spontaneous" and environmentally induced, as we are. (presentation: slides 13-16)

Which explains why so many independent scientists, as well as industry toxicological studies, continue to use the SD rat.  

We wonder if Sanders has noticed that 1 in 3 people in the UK get cancer – about the same as Seralini's control rats. And rates of breast cancer – which may or may not be a human equivalent to the mammary tumours seen in the rats – are escalating. It's been the most common type of cancer in the UK since 1997.

The key point about Seralini's tumour findings was that the controls got some tumours, but that the treated groups got significantly more tumours, which began sooner and were more aggressive, than the control groups. This argument is explained here:

So even if a researcher used a strain of rat that was bizarrely prone to tumours (though this is not the case with Seralini), this would not matter in the context of the controlled experiment, because you are looking at the additional number of tumours caused by the treatment, over and above the "spontaneous" background level. 

To illustrate the point by an analogy: We know that a small proportion of people who never smoke get lung cancer. If you smoke, the rate/risk of getting lung cancer is about 12 times higher than if you don't smoke. The measurement is called a "relative risk". So, imagine that there is an ethnic group of people with a higher rate of naturally occurring lung cancer. We know that if people in that group smoke, their rate of lung cancer will still increase like everybody else.

This is a basic principle of science and it is worrying that Sanders's claims on this front are not challenged by the science correspondents of the media.

Sanders also implies that the lack of restriction on the rats' diets was a confusing factor because it made the rats more prone to tumours. But again, the control rats also had an unrestricted diet but got far fewer tumours.

And how many humans does Sanders know who eat a "restricted" diet in order to avoid getting cancer from their intake of GM foods and Roundup? Unrestricted feeding is a standard practice in such research, and reflects human reality.

Now we move on to Sanders's comment, "There is a lack of information on the composition of the diet."

We wonder if Sanders has even read the paper that he is dismissing. 

Seralini clearly says that the rats' diet was the standard diet known as A04 (Safe, France). You can get details of this diet with a 30-second Google. The only difference in the diets was the two treatment substances: GM maize NK603 and Roundup. 

This is proper scientific practice. The only variables should be the substances you are testing; in this case, the GM maize and Roundup. It is also in accord with EU law, which says that the GM maize must be compared with its non-GM counterpart that is as genetically similar as possible, but that hasn't been genetically engineered. This spots differences caused by the genetic engineering process, which is the point of the GMO safety assessment.

Seralini provides much more dietary information than many authors of such studies and massively more than Monsanto gave in its 90-day feeding trial with NK603 maize, which led to its approval. Seralini's team published a re-analysis of Monsanto's data, which wasn't peer-reviewed and published, in a 2009 paper (de Vendomois, J. S., F. Roullier, et al. (2009). A comparison of the effects of three GM corn varieties on mammalian health. Int J Biol Sci 5(7): 706 726.).

Read this paper and prepare to be shocked. Monsanto: 
*used a number of different control diets containing unrelated varieties of maize, introducing many variables into the experiment that hide the effects of the GM process
*used far more control animals than treated, which again would hide effects of the GM diet, and
*provided no data to show that the non-GM control diets were even non-GM!

Sanders then makes a speculative claim that the effects found by Seralini's team could have been due to mycotoxins from improper storage. 

But all feeds were biochemically analysed to make sure they weren't contaminated with such toxins.

Let's assume, for the sake of argument, that some mystery toxin was present that escaped the researchers' notice. (Note: if we put this forward as a reason to dismiss Seralini's study, we have to prove it through further experiments. Until then, our argument is simply a hypothesis.) 

We know from Seralini's paper that the GM and non-GM maize varieties were grown side-by-side in the same conditions. If storage conditions were also the same, as would be expected in an experiment of this type, then that leaves us with another interesting question: why would the GM maize end up with a mystery toxin in it, which the non-GM maize didn't have in such dangerous quantities?

If we were Sanders, we wouldn't go there.
3. GMWatch profile of Tom Sanders
Sources here:

Prof Tom Sanders is Head of the Nutritional Sciences Research Division, King's College London. Sanders has made a name for himself defending the safety of the controversial artificial sweetener aspartame (sold as Nutrasweet) in the media. He said: "The key point is that we can help people to live healthier lives if they can reduce their calorie intake. Sweeteners (aspartame) have a valuable role to play in the fight against obesity." 

In response to the view of the American Association of Neuropathologists that there was a link between aspartame and brain cancer, Sanders said: "There is simply no evidence to show aspartame causes cancer. It is probably the most stiffly tested substance we consume."

Sanders was the chief "top scientist" quoted in a press release from Nutrasweet dismissing a research paper by Dr John Olney of the Department of Psychiatry, Washington University Medical School, that suggested a link between brain tumours and aspartame. Sanders said Olney's paper was "preposterous", "seriously flawed" and "without merit". However, Sanders did not provide any arguments to back up his claims. Olney, in contrast, did back up his arguments, in his peer-reviewed research paper.

Though Sanders believes aspartame can help people live healthier lives (above), he is not so impressed by the health benefits of fresh fruit. In an article titled "The myths of fruit", Sanders was quoted as saying that drinking liquidised fresh fruit compared unfavourably to drinking Coke:

"If you liquidise it into goo it's just like drinking ordinary Coke. Or worse, actually. It's still a sugary drink. A lot of people on diets don't realise that if they're drinking loads of apple juice or orange juice, it's got a lot of calories in. If you drink a litre of apple juice a day, it'll be 400 calories." 

However, this claim only takes into consideration the one factor of calories – not vitamins and minerals, which are arguably a more important factor in choosing a drink. People on a diet still need their nutrients – one could say, more than those eating an unrestricted diet. 

Affiliations and consultancies

An article in The Independent in 1996 described Sanders as "Nutrasweet's professional consultant". At this time, Nutrasweet was owned by Monsanto, which acquired G. D. Searle & Company, the company that owned the patent on aspartame, in 1985. Investment firm J.W. Childs Associates purchased Nutrasweet from Monsanto in 2000.

Food writer Felicity Lawrence, in a 2010 article that scathingly commented on the nutritional value of manufactured breakfast cereals, reported that the cereals manufacturing industry had "recruited Professor Tom Sanders, head of the nutrition department at King's College London, to defend 'breakfast cereals served with semi-skimmed milk' as 'low energy meals that provide about one fifth of the micronutrients of children'." 

Criticism of study on GM potatoes

In 1998 researcher Arpad Pusztai of the Rowett Institute in Scotland went public with his team's research showing that GM potatoes had harmful effects on rats (the research was later published in The Lancet).

In the subsequent media furore, a rapid rebuttal campaign swung into action. Sanders was quoted in a Scientific American article of 1999 as asserting that all that Pusztai's experiments "definitively proved was that eating raw potatoes, which are indigestible, is harmful to mammals – something that has been known for many years."

In fact, in the research study, harmful effects were found from feeding cooked GM potatoes, too, but these harmful effects were not found in the rats fed the non-GM control potatoes, even when raw. In other words, Sanders's argument was completely spurious, though it went unchallenged in the media.

Sanders gave a second 'spoiler' quote to The Independent, also in 1999, in which he questioned the validity of Pusztai's findings on the basis that in the GM-fed rats, "differences in brain weight were reported, as brain weight is generally not influenced by diet in adult rats."

By Sanders's logic, only scientific findings that Sanders had heard about before and was expecting, were acceptable, and no unexpected results from GM food (in this case, shrinkage of the brain) could possibly be valid.

Sanders also claimed in his interview with The Independent that the ill effects seen in the rats were due to protein deprivation, when in fact the treatment and control diets had the same amount of protein (were isoproteinic) and all diets met government standards for nutritional content of experimental rodent diets.

Sanders (or the publications) did not disclose when he gave his 'spoiler' quotes in 1999 to Scientific American and The Independent that he was either currently or in the recent past (1996) a consultant to Nutrasweet, a Monsanto-owned company. Indeed, The Independent should have known this, as a 1996 article in the same newspaper identified him as a consultant to Nutrasweet.