GM Free Cymru

Crucial paper 55: Glyphosate is probably carginogenic to humans

Date Added to website 23rd June 2015

This short report from the Cancer Monograph Working Group of the IARC and WHO has caused quite a stir, because it confirms a probable link between glyphosate and cancer in humans. Many people have been saying this for a very long time, but this is the highest-profile committee so far to have come out and stated the link is such powerful terms. The working group declares tht the evidence of a glyphosate - cancer link in animals is "sufficient" and that there is limited evidence of glyphosate causing non-Hodgkin lymphoma and genotoxicity and oxidative stress in humans. Inevitably, when the report appeared in The Lancet, there was global media coverage, and Monsanto and the rest iof the GMO "establishment" has sought to cast doubt on the report, questioning the authors' impartiality and expertise! Monsanto went way over the top, referring to the report as "junk science"........ But the WHO has refused to be intimidated, and the full Report will probably appear next year. In the meantime, the battle of words continues.

"Carcinogenicity of tetrachlorvinphos, parathion, malathion, diazinon, and glyphosate"
Kathryn Z Guyton, Dana Loomis, Yann Grosse, Fatiha El Ghissassi, Lamia Benbrahim-Tallaa, Neela Guha, Chiara Scoccianti, Heidi Mattock, Kurt Straif,
on behalf of the International Agency for Research on Cancer Monograph Working Group,
IARC, Lyon, France
Published Online: 20 March 2015
The Lancet Oncology



Glyphosate is a broad-spectrum herbicide, currently with the highest production volumes of all herbicides. It is used in more than 750 different products for agriculture, forestry, urban, and home applications. Its use has increased sharply with the development of genetically modifi ed glyphosate-resistant crop varieties. Glyphosate has been detected in air during spraying, in water, and in food. There was limited evidence in humans for the carcinogenicity of glyphosate. Case-control studies of occupational exposure in the USA,14 Canada,6 and Sweden7 reported increased risks for non-Hodgkin lymphoma that persisted after adjustment for other pesticides. The AHS cohort did not show a signifi cantly increased risk of non-Hodgkin lymphoma. In male CD-1 mice, glyphosate induced a positive trend in the incidence of a rare tumour, renal tubule carcinoma. A second study reported a positive trend for haemangiosarcoma in male mice.15 Glyphosate increased pancreatic islet-cell adenoma in male rats in two studies. A glyphosate formulation promoted skin tumours in an initiation-promotion study in mice. Glyphosate has been detected in the blood and urine of agricultural workers, indicating absorption. Soil microbes degrade glyphosate to aminomethylphosphoric acid (AMPA). Blood AMPA detection after poisonings suggests intestinal micro bial metabolism in humans. Glyphosate and glyphosate formulations induced DNA and chromosomal damage in mammals, and in human and animal cells in vitro. One study reported increases in blood markers of chromosomal damage (micronuclei) in residents of several communities after spraying of glyphosate formulations.16 Bacterial mutagenesis tests were negative. Glyphosate, glyphosate formulations, and AMPA induced oxidative stress in rodents and in vitro. The Working Group classifi ed glyphosate as “probably carcinogenic to humans” (Group 2A).

For the very petulant response of Monsanto and the Glyphosate task Force, see these:
Monsanto seeks retraction for report linking herbicide to cancer
By Carey Gillam, Reuters
The response by the pesticide industry association, the Glyphosate Task Force, is here: