14 Jul 14

Exploring GM Foods (Part II – The Curious Case Against Glyphosate)

Examining the validity of the cases made against Glyphosate, and how it might have finally met its match.

If Hypocrisy was Meursault’s mother she would still be alive, leaving Camus to conjure up some other iconic first sentence.

Our world is largely a product of the great Industrial Revolution that, much as some would like, cannot die, it can only spin further revolutions – in economy, in transport, in agriculture, in the way we live. Apologies; the process is irreversible.

We pretend we are keepers of someone else’s conscience but in reality we are prisoners of our own. Why, then, the hypocrisy? Does it satisfy some primeval need in us, that even as we enjoy unabashedly the fruits of industrial labour, we insist on returning to a medieval idyll our ancestors were only too glad to escape from?

France, which gets 80 per cent of its energy through nuclear reactors, emits four times less CO2 per kwh than Denmark that doesn’t produce any nuclear energy at all. America, that grows more glyphosate-resistant GM crops than any other country in the world has reported not a single death because of it. We usurp gladly every other invention the Americans have come up with – iPhones, anti-HIV drugs, state-of-the-art medical equipment, Internet, Boing airplanes, search engines, Cyclotron, Facebook – but are only too eager to brand them as fools for growing and consuming GM Food.

Well, Americans are no fools. Had glyphosate-resistant crops shown all the numerous deleterious affects, on mineral uptake, on soil, on water, on crop yields, as claimed by its opponents, Roundup and Roundup-ready would’ve been junked as quickly as America dispenses with despotic regimes it props up all around the world.

There is a thin line that separates science and pseudo-science; the jarring clamour to ban glyphosate and glyphosate-resistant GM crops makes it clear who snorted it first.

Greenpeace – the NGO riddled currently with financial bunglings, disgruntled third-world employees, accusations by its co-founder of gross misreporting, and carbon footprint double-speak – published recently a thesis titled: Why the World Should be Ready to Round Up Glyphosate wherein it asked for a ban on glyphosate. Their countless assertions merit a second look.

Glyphosate and glyphosate-resistant crops, begins Greenpeace, “are part of an industrial agriculture system that involves large-scale monocultures that depend on costly, polluting inputs such as herbicides.” Then, while admitting to “an urgent need to find sustainable solutions to agriculture”….“business as usual is no longer an option..” it declares grandly, “Sustainable solutions will not come from GM crops, and definitely not from GM herbicide-tolerant crops.”

One could have given their battle cry some credence had they got even the basics right. They don’t. “Glyphosate: how does it work?” asks Greenpeace rhetorically and then proceeds to invent a laughable new scientific mechanism (see Part I for the actual mechanism of action of glyphosate), just so it can harp on the chelating properties of glyphosate that it claims are responsible for environmental damage. “Glyphosate chelates (or binds) manganese, making it unavailable to the EPSPS. Because manganese is essential for EPSPS to work, inhibiting it in this way subsequently affects an essential biochemical pathway in plants, the shikimate pathway, leading to a shortage of vital molecules for building proteins and causing the plant’s death.”

If, at the first step itself, all previous scientific findings – the biochemical investigations, the X-ray structures, the genetic discoveries – are discarded so as to buttress the pseudo-scientific theory of chelation, one can imagine the state the rest of the climb would leave the reader in. Yes, exhaustion.

The malady doesn’t end there. Under the heading, Acute Effects, Greenpeace says, “A number of deaths have resulted from intentional ingestion (suicide), preceded by metabolic acidosis, respiratory and kidney failure, cardiac arrest, seizures, and coma.” All true, except that this fate befalls those who ingest glyphosate neat, an outcome not dissimilar to hundreds of farmers who take their own lives every year by drinking pesticide as a result of crop failure and state apathy. Glyphosate, like Baygon spray, is poison – it is not to be glugged.

Greenpeace then goes on to list reproductive, oncological, and neurological effects caused by glyphosate, and quotes research findings that have been, on numerous occasions and by various research labs, brought into serious question.

For example, it refers to the findings of the Seralini group, even displaying it prominently, without once mentioning that in the past Greenpeace has funded the group and publicised widely its claims that GM maize causes hepatotoxic effects – claims that were then investigated by European Food and Safety Authority, EFSA, and found to be false. It may be recalled that in 2012, Seralini and co-workers had published a paper titled: Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize, a finding that Greenpeace decreed to be the final nail in the glyphosate coffin. Not quite. Two years and tens of peer-complaints later, the journal took the unprecedented step of retracting the study. “A more in-depth look at the raw data,” said the journal, “revealed that no definitive conclusions can be reached with this small sample size regarding the role of either NK603 or glyphosate in regards to overall mortality or tumour incidence.”

Other experts and scientists were more scathing, calling the study little more than pseudo-science, riddled with many “errors and inaccuracies” resulting in “highly misleading conclusions, whose publication in the scientific literature and in the wider media has caused damage to the credibility of science and researchers in the field.

The same Seralini group had also reported that GM maize varieties induce a state of hepatorenal toxicity, causing disruption in liver function parameters as well as the heart, adrenal glands, spleen and haematopoietic system. Yet again the EFSA was forced to reconvene and look into the matter. It concluded that “the authors’ claims, regarding new side effects indicating kidney and liver toxicity, are not supported by the data provided in their paper.” The experts were of the unequivocal view that there were “no indications of adverse effects for human, animal health and the environment.” Their findings – reached after a thorough investigation – should’ve been required reading for Greenpeace before it backed vociferously the Seralini group. They weren’t.

The Greenpeace document also quotes liberally the research work of Carrasco and co-workers, in particular their finding that glyphosate-based herbicides produce teratogenic effects on vertebrates. In this study, deformities caused by glyphosate on frog and chicken embryos were reported, with “marked alterations in cephalic and neural crest development”.

Conveniently, Greenpeace forgets to mention that this very study had created quite a furore when it was first published, with rebuttals that found fallacies and counter rebuttals that refuted the fallacies found. Expectedly, in his rebuttal Carrasco cited the work of Seralini generously. To be sure, this is the way science should progress – discovery, followed by reporting, followed by thorough investigations of the scientific claims, followed finally by rebuttals and counter-rebuttals – but it is amply evident that there are too many vested interests in this story. This is true especially for the reporting of LD50 (median lethal dose) values of glyphosate.

Greenpeace should also have known that in 2012, using the same methods pioneered by Carrasco, scientists had discovered that even administration of caffeine leads to defective neural tube closures in embryos and expression of several abnormal morphological phenotypes. Replace caffeine with glyphosate in the report’s title: Caffeine exposure can result in malformations of the neural tube and induce other teratogenic effects, and one can set alarm bells ringing for those who are awake but want to be woken up nonetheless.

Remarkably, the 2012 caffeine finding corroborates similar studies conducted on chicken embryos back in 1988 and 1995 that found caffeine to be causing cardiovascular malformations. The interference by caffeine in embryonic development was also reported by Li and co-workers in 2012. Of little importance, then, that caffeine has been consumed with glee for thousands of years, and long will this love-affair continue unless Greenpeace now decides to do a dharna outside Starbucks.

Countering another of Greenpeace claims, that glyphosate possesses estrogenic activity and an ability to affect reproduction, a comprehensive review of scientific literature found “no solid evidence linking glyphosate exposure to adverse developmental or reproductive effects at environmentally realistic exposure concentrations.” Furthermore, a recent 7-month scientific study conducted on fish found that glyphosate-resistant GM soy “did not appear to cause any adverse effects on organ morphology or stress response compared to non-GM soy.”

Finally, in firming up their chelation theory, Greenpeace also ends up quoting repeatedly the work of scientists who say the following about the mechanism of action of glyphosate: “Glyphosate kills weeds by tying up essential nutrients needed to keep plant defences active. Glyphosate doesn’t kill weeds directly but shuts down their defence mechanisms so pathogens in the soil can mobilize and kill the weeds.” “Tying up” essential nutrients? No further argument is necessary to counter theories that fly in the face of decades of reproducible scientific research on glyphosate mode of action (see Part I). But what is truly regrettable is how seriously such reports are taken by policy-makers and environmentalists in the developing world.

In February of this year, Dr Jayasumana, a Sri Lankan scientist, authored a paper wherein he hypothesised – without conducting a single experiment – that glyphosate might be to blame for the mysterious Chronic Kidney Disease, or CKD, that has killed hundreds of Sri Lankan farmers. According to him, glyphosate, because of its metal chelating properties, bound metal ions like Calcium and Magnesium and caused CKD.

Evidence – scientific and otherwise – does not bear out Dr Jayasumana’s hypothesis. CKD affects thousands of farmers in Central America, and while glyphosate use is uniformly high across the farmlands, CKD is prevalent only in the coastal areas. Why? Heat, think experts is the simple explanation. Dehydration leads to excess conversion of glucose to fructose and fructokinase, the fructose-metabolising enzyme, creates high levels of uric acid and other harmful chemicals that damage the kidney. The results of another scientific study show that in 96.5 per cent of CKD patients the urine glyphosate levels come out well below reference levels. The authors suggest selenium deficiency or a predisposed genetic susceptibility could be the reason behind CKD.

As for the chelating properties of glyphosate being responsible for CKD, it turns out that many natural chelators present in plants and soil are better than glyphosate at binding metals, especially Iron and Manganese. Glyphosate can indeed chelate metal ions – a property that, many conjecture, allows it to prevent proper uptake of micronutrients by plants. However, numerous scientific studies refute this argument, too, showing instead that free micronutrient concentrations are not affected even by large dosage application of glyphosate.

The bio-degradation of glyphosate into Aminomethyl phosphonic acid, AMPA – something that worries the naysayers immensely – has also been studied extensively over decades, and more recently through the use of radioactive Carbon 14. The results are at variance with Dr Jayasumana’s hypothesis. Studies show that repeated glyphosate use is not likely to hamper its eventual degradation by the soil-dwelling bacteria. After 41 days of plant growth following glyphosate application, only 0.006% of radiolabelled glyphosate was detected in the growing crop. Furthermore, glyphosate does not affect mineral nutrition in crops, nor does it lead to crop disease.

Facts are cheap, opinion is sacred. Jayasumana’s theory made global headlines and in March 2014, barely three weeks after he had reported the hypothesis – with no follow-up scientific study to validate it – the Sri Lankan President ordered an immediate ban on glyphosate. “The President was told of the report and he ordered the ban,” said a Lankan minister, simply. But the farce was not quite over. Two weeks later, the President lifted the ban. This time round, it appears he heeded the advice of an official according to whom the Lankan farmers were succumbing to CKD well before glyphosate came to be used in Lanka. “All the paddy farmers used Paraquat at that time (in the 1980s).” Indeed, as late as May 2013, the American Environmental Protection Agency, EPA, concluded that glyphosate “does not pose a cancer risk to humans” and so far as glyphosate exposure through food and water were concerned, the exposure is “no more than 13% of the Acceptable Daily Intake (ADI).”

The question shouldn’t be about Monsanto or BASF or any other “blood for food” multinational company. The question should be about scientific validity of the product, of how stringently it has been studied and approved by the international regulatory authorities. Tragically, this selective highlighting of scurrilous, hypothetical, irreproducible, pseudo-scientific findings by Greenpeace and other vested interests has only managed to obfuscate the one problem that does plague glyphosate, and it wouldn’t be an exaggeration to state that if glyphosate goes down it’d be because of one reason and one reason alone – it has met its match. Evolution.

Rampant use – and misuse – of glyphosate over the past decade has resulted in a large number of weeds developing resistance to it. Of most concern is a weed called waterhemp, Amaranthus rudis that runs wild in GM soy and cotton plantations. These weeds that were earlier killed easily by glyphosate have now evolved through natural selection to withstand the herbicide. The International Survey of Herbicide-resistant Weeds website lists all the Roundup-resistant weeds discovered thus far, around 219 in 18 different countries Somewhat quirkily, this so-called resistance epidemic made headlines outside of scientific journals when it was reported that, because of extensive aerial spraying of glyphosate on coca plantations by American and Colombian anti-narcotic agencies, a new species of coca had been identified by the drug traffickers, one that was completely glyphosate-resistant.

The crisis is akin to what is faced regularly in Medicine – antibiotic resistance. Over-dependency and over-use of antibiotics – especially in countries like India where such drugs are available across the counter – has resulted in resistant strains called superbugs. Resistance to glyphosate is no different. A recent study found that the weed Amaranthus palmeri, in its desperation to avoid being killed by glyphosate, managed to “clone” its own single-copy EPSPS enzyme an astonishing 160 times and distribute it across each of its 34 chromosomes. In the end, the weed was producing so much of EPSPS it managed to eat up all glyphosate there was.

One can try but one would fail. Mother Nature cannot be beaten or conquered, by man or molecule. One can only accept defeat and start afresh. New herbicides would have to be discovered to address this problem but until then the farmers need to use a combination of herbicides to make it difficult for the weed to develop resistance. To be sure, resistance to herbicides is a reality even when glyphosate is not used. As many as 64 weeds are resistant to the herbicide atrazine – and there exists no atrazine-tolerant GM crop. Even so, researches are racing ahead to discover the next glyphosate and it is only a matter of time before they find one.

Discovery of a new molecule would herald the demise of glyphosate that many so dearly wish for. It is bound to happen – safer, gentler, more effective molecules, natural or synthetic, are forever around the corner – and when it does one hopes that Franz’s legacy may yet be remembered as one that, in his own words “benefited mankind”.

(In Part III – The Third Eye of Shiva – we shall discover how one environmentalist’s obsession has shaped, for better or for worse, the public discourse on GM Foods)

 

 

This article first appeared in newslaundry on Jul. 14, 2014.

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