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Who's afraid of GMOs?

Opposition to genetically modified crops is fierce, but how much of the anti-GM stance is based on science? Not a lot, argues Paul Willis.

Don't you hate it when another of your favourite foods or other indulgences turns out to be bad for you? I was doubly taken aback when an article came across my desk recently suggesting I should stop drinking some of my favourite beers.

Not that I hold onto my faith in beer with an almost religious fervour but to have my devoted worship of the amber God brought into question only compounded my indignation. But shock turned to anger when it became apparent that this maligning of my holy water was largely built on nonsense and non-science.

At the core of the blasphemy was the recurring anti-GMO theme running through the article.

We're told that some of the "harmful ingredients" found in some beers include GMO corn syrup, GMO corn and GMO sugars. Elsewhere it claimed GMO rice had been found in Budweiser (which I wouldn't recommend anyone drink anyway) and Michelob Ultra contains GMO dextrose (again, there are much better reasons not to drink this one).

It went on to laud a list of GMO-free beers (all of which I'd never heard of) and rounded out with an endorsing statement about spreading the word about GMO beers in an effort to change people's beer-buying habits.

The first glaringly obvious flaw in the anti-GMO argument concerns GMO corn syrup and GMO sugars (including GMO dextrose). These are heavily processed and refined products derived from genetically modified plants. They are no different from non-GMO sugars and syrups. They contain no GM material. Thus their safety for human consumption and nutritional parameters can be no different from their conventional counterparts.

GMO is simply wafted through the article like some dietary boogieman in an attempt to scare and intimidate while simultaneously clouding and confusing the reality of the matter.

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Campaign tactics

These have been the hallmarks of the various anti-GMO campaigns that have rallied through the media over the last couple of decades. A more sober assessment of the public GMO debate reveals that it's not really about the science of the safety and impacts of growing GMO organisms, it's more a backlash against perceived corporate control of agriculture and food as well as an anti-authoritarian stab at the endorsement of GMO and biotechnology by governments and institutions.

When it comes to the science, the only case that can be mounted against GMOs must be based on misrepresentations or misunderstandings of what GMOs are and how they work. Or, worse still, there is deliberate deception involved in spreading the anti-GM 'science' message.

There are deceptive uses of words so that "research" can place a Google search on par with a double blind, controlled experiment and even "science" itself can embrace vague claims and untested hypotheses. There's a pervasive lack of appreciation for how many science-based institutions vouch for the safety of GMOs including The American Association For the Advancement of Science (or AAAS), World Health Organization and The European Commission.

The broad claim that GMOs are not safe ignores the fact that no food technology or supply chain is safe and also ignores the more than 20 years research and more than 2000 peer-reviewed studies of GMOs that all support their safety.

Add to this the host of independent studies that complement our understanding of the safety of GMOs both as part of the food chain and in the environment and you have a pretty convincing case that the science is 'in' on GMOs and the science is good.

Dig a bit deeper and five outright lies about GMOs can be exposed:

1. GMOs are unhealthy

A huge body of research has failed to find any unhealthy outcomes from the consumption of GMOs.

2. GMOs increase herbicide use

This one revolves around some GMOs that have modifications that confer some tolerance to some commercial herbicides. It appears that what has happened is that the amount of herbicide applied per acre of crop has declined but, because more acres are under crop, overall herbicide use has increased.

3. Genetic engineering creates dangerous side effects

Despite predictions of unpredictable side effects from genetic manipulations, none have been found.

4. GMOs harm the environment

The main concern here are things like GMO crops with built-in insecticides killing caterpillars. Well yes, that's what they are designed to do, but only in the farm environment where the GMOs are grown. There is no escape into the wild and conferring insect resistance to other plants. There is no broader impact on the environment of GMOs.

5. GMOs do not increase yields, and work against feeding a hungry world

This one is a particularly nasty one because it's at the pointy end of much of the benefits of spreading GM technology to the developing world. One review article found average yield increases for developing countries ranging from 16 per cent for insect-resistant corn to 30 per cent for insect-resistant cotton and an 85 per cent yield increase observed in a single study on herbicide-tolerant corn. Clearly GMOs have an important role to play in feeding a rapidly growing global population. But the scare-mongering of the anti-GM movement has led to some countries, particularly in the developing world, banning GM crops.

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Séralini experiment

Still the dubious case studies and discredited arguments of the forces of anti-GM find a voice in the modern media. Perhaps the most celebrated case in recent years has become known as the Séralini affair. In September 2012 a group led by French Researcher Gilles-éric Séralini published the results of an experiment they had conducted. Over a two-year lifespan rats were fed NK603 maize, a herbicide-resistant corn made by Monsanto. They also fed the rats on the herbicide RoundUp.

Prior to this publication, Séralini had built a reputation for producing papers that purported to show a variety of negative health effects from eating GMOs and every single one of these publications had been challenged and found to be in error in one way or another. The 2012 paper recorded dramatic increases in the mortality rates of both male and female rats that had the treatment of GMO corn and herbicide. He concluded this was evidence of the toxicity of both the GMO and the herbicide.

But there were all kinds of problems with Séralini's methods, not least of which was selecting a strain of rats prone to develop cancers. Similar studies conducted independently of the Séralini lab found no toxic effects from the GMO or the herbicide. Criticism grew and he was requested to retract the paper. When he refused, it was retracted for him just over a year after publication.

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Farmer Glöckner

Then there are claims of horrendous side effects of GMOs coming from farmers and others who actually grow the stuff. Perhaps the most celebrated case is that of German farmer Gottfried Glöckner. In an interview earlier this year he alleges gobsmackingly shocking tactics by a GMO company and authorities supposedly to silence him in his ongoing quest to reveal what happened to his herd of dairy cows when he fed them genetically modified corn.

Ultimately Glöckner spent two years in prison because he refused to back off on his charges that the Anglo-Swiss GMO company, Syngenta, had provided him with what he claims was "highly toxic GMO maize seeds" that killed some of his prize dairy herd and his poisoned his land.

The Glöckner saga began in 1997 when he signed up to be part of a trial for growing Syngenta' newly approved GMO corn (Syngenta Bt176) as fodder for his dairy herd. In 2000, he started to record infertility, sicknesses and deaths among the herd as well as severe birth defects in newborn calves. All up he lost 12 cows.

Glöckner figured his stock and property had been poisoned by Bt toxins — a protein produced by the bacterium Bacillus thruingiensis, which is toxic to chewing insects — in the GM crops.

But nowhere in his interview will you find mention of other results from independent investigations into his farm and farming practices that found raised levels of fungal toxins in some of his fodder, the poor quality of the grass silage used as feed, significant changes to the feeding practices within too short a space of time (including insufficient quantities of essential minerals) and overfeeding by around 25 per cent excess energy and 42 per cent excess protein resulting in overweight dairy cows (which can lead to metabolic and calving problems).

Further the botulism pathogen, Clostridium botulinum, was found in the gut of two of the dead cows. It looks like only two of the cows were examined for the presence of this pathogen so we don't know if it was present in the other ten but this disease can spread rapidly amongst an entire herd and kill them all within weeks. Apparently the infection was also found in three of the five surviving cows.

The independent studies found no evidence that Bt maize was the cause of death. Add to that the undeniable fact that Bt176 maize has been fed to many other animals since 1998 with no similar results as what happened on poor Farmer Glöckner's property and you'd have to conclude that it most certainly isn't the villain in this story.

Now, if Glöckner's accusations about the tactics to silence him are substantiated, then by all means, the law of his land ought to come into play and justice be served. But that's not a debate about the safety and efficacy of Bt176 maize in particular or GMOs in general. This case serves to highlight that the main thrust of the arguments against GMOs is not about the science of their safety or negative environmental impacts. It's more a concern about societal and political structures and operations.

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Bee alarmed?

Finally, I'd like to leave you with this enigmatic meme that's been floating around the internet of late:

Source: http://ow.ly/i/5zc5l/original

I love bees, particularly the little native guys that happily pollinate my garden without a fuss or care in the world. And the catastrophic collapse of bee numbers elsewhere in the world is cause for great alarm. It threatens the viability of whole sectors of the agricultural economy that rely on the pollination services of these cute little insects. So we should all be concerned at their loss and strive to do something about it. They still haven't nailed the culprit but the finger is pointed strongly at neonicotinoid insecticides, which are now banned across Europe. But there is no demonstrated link that I can find between the great bee die-off and GMOs.

One hypothesised pathway of bees dying from ingestion of GMOs with Bt toxins simply can't work: this built-in insecticide works on insects that chew on the plant. Bees don't chew on plants. The possibility of bees ingesting Bt toxin through nectar and pollen has been investigated and shown not to be of concern.

The bee story is a microcosm of the anti-GMO story at large. Complex and confusing situations where clarity is muddied by well-meaning, but largely misinformed, parties.

We're trying to deal with some of the biggest questions confronting us in the world today: how do we feed an increasing population on decreasing arable land? It's a battle we must fight using all the weapons at our disposal.

Blindly pointing the finger at GMOs does not help.

About the author: Dr Paul Willis is the director of RiAus, Australia's unique national science hub, which showcases the importance of science in everyday life. The well-known palaeontologist and broadcaster previously worked for ABC TV's Catalyst program.



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