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IARC: Glyphosate, probably carcinogenic to humans

21 March, 2015
Weedkiller alert over cancer link. By Camilla Turner. telegraph.co.uk,   March 21,  2015. The World Heath Organisation has declared that glyphosate, one of the UK’s most popular herbicides marketed as Roundup, is ‘probably carcinogenic’.The World Health Organisation’s cancer agency has declared that one of the UK’s most widely used weedkillers is “probably carcinogenic to humans”.Amateur gardeners and professional farmers have been urged to “think very carefully” about using the popular herbicide Roundup, which contains glyphosate.A summary of the International Agency for Research on Cancer’s (IARC) report, published in The Lancet Oncology, said that the herbicide had been detected “in air during spraying, in water, and in food”.
IARC: Glyphosate, probably carcinogenic to humans
Blanco o negro
Camilla TurnerIt had also been detected “in the blood and urine of agricultural workers, indicating absorption”.
Roundup weedkillerRoundup weedkiller contains glyphosate which the WHO has said is ‘probably carcinogenic to humans’ Photo: AlamyAndreas Kortenkamp, professor of human toxicology at Brunel University, London, said that the people who are most at risk are those applying the weedkiller to their plants.“Professional gardeners would industrial strength glyphosate to totally wipe their garden of all plants. Amateur gardeners can also buy it as Roundup in a formulation which is not as strong,” he said.“Anyone who sprays it could get a whiff of it. People should be very careful with this stuff and consider whether they need it. Home gardeners should hand weed to be on the safe side.”The IARC asked 17 experts to assess five organophosphate pesticides. Glyphosate, the most widely used of the five, was placed in category 2A, meaning “possibly carcinogenic to humans”, following evidence from studies carried out in America, Canada and Sweden.

Amateur gardeners have been urged to hand week rather than use Glyphosate, (Andrew Crowley)

Prof Kortenkamp said that the IARC’s announcement would be taken very seriously by national agricultural regulatory bodies."It is one of the most widely used herbicides worldwide," he said. "The important thing is 2A categorisation in the IARC is equivalent to 1B in the European Union, which means it will not receive authorisation."Prof Kortenkamp said that glyphosate is designed to inhibit an enzyme that is very important for photosynthesis.“It gets into the plant, then shrivels it up so it turns brown and then dies,” he said. “It is marvellous for plants with horrible invasive roots like dandelions or bind weed”.Glyphosate is used in more than 750 different products for agriculture, forestry, urban, and home applications worldwide.The IARC’s report said that its use has increased sharply with the development of genetically modified glyphosate-resistant crop varieties.In one study the IARC report cited, glyphosate induced a positive trend in the incidence of a rare tumour, renal tubule carcinoma, in male mice. In another study, there was a positive trend for haemangiosarcoma in male mice.The IARC’s findings contradict a study by the German government earlier this year which concluded that glyphosate was “unlikely to pose a carcinogenic risk in humans”.Monsanto, a multinational agriculture company, which markets glyphosate as Roundup, issued a statement saying it disagrees with the IARC’s classification.Dr. Philip Miller, Vice President Global Regulatory Affairs, Monsanto, said: “We don’t know how IARC could reach a conclusion that is such a dramatic departure from the conclusion reached by all regulatory agencies around the globe.”He said that Monsanto has issued an “urgent request” for WHO to account for which scientific studies were used in their analysis and which were “disregarded”.A Defra spokesperson said that Glyphosate is currently approved as a herbicide in the EU, but it is “under review to ensure it is safe”.They said: “There are extensive regulations in place so that people and the environment are protected from pesticides.”Glyphosate is one of the world’s most popular pesticides (Getty Images)
Note from SerTox: article send by Juan Piola (London)

_______________________________________________________________________________________See PDF related: Carcinogenicity of tetrachlorvinphos, parathion, malathion, diazinon, and glyphosate

See also in The Lancet.com: Carcinogenicity of tetrachlorvinphos, parathion, malathion, diazinon, and glyphosate

Comments from Monsanto

Glyphosate- IARC 2A Carcinogen Classification

Glyphosate- IARC 2A Carcinogen Classification

by Daniel Goldstein, posted on 10:53 AM, March 20, 2015

NOTE- For those who do not know me- Author is a full time employee of Monsanto, leading manufacturer of glyphosate.

IARC has just posted a document classifying glyphosate as a Class 2A human carcinogen. http://www.thelancet.com/journals/lanonc/article/PIIS1470-2045(15)70134-8/abstract

This conclusion is in stark disagreement with the EPA and with the comprehensive assessment of glyphosate recently released as a part of the EU re-registration process for glyphosate by the German BfR, both of which conclude a lack of cancer risk with this molecule.

The primary association was with Non-Hodgekin’s Lymphoma based on four case-control studies suggesting possible increased risk. However, the very large and prospective cohort Agricultural Health Study found no such association.

The animal data cited relates to sporadi c tumor findings in individual studies which do not demonstrate dose- response and which have failed to appear in multiple studies (glyphosate had six independent registrants and hence multiple data sets, now merged since it is off-patent).

While they provide citations for genotoxicity, they appear to have discounted a very large number of studies indicating a lack of genotoxic effects.

I would be happy to provide references and additional information to anyone who is interested.

Current regulatory opinions provided below. (hyperlinks links may not be live below)

Dan ([email protected])

U.S. Environmental Protection Agency
“EPA has concluded that glyphosate does not pose a cancer risk to humans.” 2013 Federal Register Notice (FR 25396, Vol. 78, No. 84, May 1, 2013).

U.S. Environmental Protection Agency
“Several chronic toxicity/carcinogenicity studies…resulted in no effects based on the parameters ex amined, or resulted in findings that glyphosate was not carcinogenic in the study” and “Glyphosate does not cause mutations.” U.S. EPA. (1993) EPA: Glyphosate. EPA-738-F-93-011. U.S. Environmental Protection Agency, Washington, D.C.

German Federal Institute for Risk Assessment (BfR)
“In epidemiological studies in humans, there was no evidence of carcinogenicity and there were no effects on fertility, reproduction and development of neurotoxicity that might be attributed to glyphosate.” Glyphosate Renewal Assessment Report, Germany, Rapporteur Member State for the European Renewal of Approval for Glyphosate (2014)

Australian Pesticides and Veterinary Medicines Authority
“The APVMA currently has no data before it suggesting that glyphosate products registered in Australia and used according to label instructions present any unacceptable risks to human health, the environment and trade. … The weight and strength of evidence shows that glyphosat e is not genotoxic, carcinogenic or neurotoxic.” Australian Government, Australian Pesticides and Veterinary Medicines Authority (2013)

The Toxicological Monograph presented to the 2004 Joint FAO / WHO Meeting on Pesticide Residues concluded, “In view of the absence of a carcinogenic potential in animals and the lack of genotoxicity in standard tests, the Meeting concluded that glyphosate is unlikely to pose a carcinogenic risk to humans.”


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