Glyphosate declared a ‘probable human carcinogen’ by international cancer agency

March 20, 2015 by Staff Reporter

Glyphosate, the active ingredient in the herbicide Roundup – used widely on GM crops – has been declared a category 2A  ‘probable human carcinogen’ by the International Agency for Research on Cancer (IARC).

The Agency, a branch of the World Health Organization, came to its conclusion as part of a recent review of the cancer-causing potential of five pesticides (the others being the organophosphates tetrachlorvinphos, parathion, malathion and diazinon). The review was made by an international panel of 17 experts and is published in the journal Lancet Oncology.

Glyphosate is the world’s most widely used herbicide. It is sold to gardeners for domestic use and, crucially, around 80% of all GM crops are engineered to be tolerant to it, allowing farmers to spray large quantities of it on these crops to kill weeds. Glyphosate is also sprayed on non-GM grain crops as a desiccant (to dry them out) before harvest. Even so, it is the herbicide’s use on GM crops that has helped drive its extensive use on farms around the world.

Biotech is…unhappy

As the news was breaking biotech company Monsanto hit back saying that the company took great pride “in the science behind, and safety of, our products” and was “reaching out” to the World Health Organization about the decision of the IARC.

The company went further by trying to downplay the importance of the decision noting WRONGLY that this classification puts glyphosate in the same category as “coffee, cell phones, aloe vera extract and pickled vegetables”.

This is a silly and deliberate misrepresentation of IARC categories. Category 2A substances are probable human carcinogens, in which “there is limited evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals.” A further category 2B (and the one to which the substances mentioned by Monsanto belong) is for possible human carcinogens in which “there is limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals”.

The difference may sound subtle but it is significant. Being a 2A probable human carcinogen, in fact, puts glyphosate in the same league as human papillomavirus type 68, inorganic lead compounds, anabolic steroids, working in a petroleum refining plant, and the dry cleaning fluid tetrachloroethylene (perchloroethylene, or ‘perc’).

The Joint Glyphosate Task Force, comprised of companies that manufacture the toxic herbicide, also issued a press statement referring to the decision as a “misclassification” and is pushing for the IARC re-review its decision.

Such reactions are a par for the course and to be expected with the amount of money at stake. Today glyphosate generates around $6 billion in sales per year.

But the evidence is compelling…and growing

While evidence of the environmental harm wrought by glyphosate – resistant ‘superweeds, destroying soil organisms, and threatening the survival of pollinators such as bees and butterflies – has been known for some time, evidence of its health effects has only relatively recently begun to accumulate.

As described in our Letter from America research shows that Roundup Ready crops contain many times more glyphosate, and its toxic breakdown product AMPA, than normal crops.

Traces of glyphosate have been found widely in the urine of European citizens. Likewise traces of glyphosate have also been found in the breastmilk and urine of American mothers, as well as in their drinking water. The levels in breastmilk were worryingly high – around 1,600 times higher than what is allowable in European drinking water. Passed on to babies through breastmilk, or the water used to make formula, this could represent an unacceptable risk to infant health since glyphosate is a suspected hormone disrupter. Recent studies suggest that this herbicide is also toxic to sperm.

Studies of animals fed GM foods and/or glyphosate, show worrying trends in terms of health impacts including damage to vital organs like the liver and kidneys, damage to gut tissues and gut flora, immune system disruption, reproductive abnormalities, and of course, tumours.

Given the way that GM ‘Roundup ready’ crops can drive up glyphosate use, the pro-GM UK government must now take very seriously this new evidence, abandon its plans to bring GM crops to this country and use public money instead to support safer, saner ways to produce food.


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