The WHO classifies the herbicide glyphosate in the second category of carcinogenic toxicity

The WHO classifies the herbicide glyphosate in the second category of carcinogenic toxicity

This information was published on March 20, 2015 by the prestigious medical scientific journal The Lancet Oncology and is available here.

To access the pdf click here.

Under the title: Carcinogenicity of tetrachlorvinphos, parathion, malathion, diazinon and glyphosate, the IARC Working Group, headed by Dr. Kathryn Z. Guyton, say verbatim regarding Glyphosate: Glyphosate is a broad-spectrum herbicide, currently the highest production volume among all the pesticides.

It is used in more than 750 different products for agriculture, forestry, urban use, and home applications. Its use has increased notably with the development of genetically modified varieties of crops to be resistant to glyphosate.

Glyphosate has been detected in the air during spraying, in water, and in food. There was limited evidence of its carcinogenicity in humans.

Case-control studies for occupational exposure in the US (14), Canada (6), and Sweden (7) report increased risks for non-Hodgkin's lymphoma, which persisted after adjusting for exposure to other pesticides. The Agricultural Health Study (AHS) cohort does not exhibit significant risk for non-Hodgkin lymphoma.

Male CD1 mice exposed to glyphosate showed a positive trend in the incidence of a rare tumor, renal tubule carcinoma. A second study reported a positive trend for hemangiosarcoma in male mice (15).

Male rats grew pancreatic islet cell adenomas with glyphosate in two studies. And with a formulation of glyphosate promoted skin tumors were promoted 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).

Detection of AMPA in blood after intoxications suggests microbial gut metabolism in humans.

Glyphosate and glyphosate formulations have induced DNA chain and chromosomal damage in mammals and in human and animal cells in vitro.

One study recorded increases in blood markers of chromosomal damage (micronuclei) in residents of various communities after spraying glyphosate formulations (16). Bacterial mutagenesis tests were negative.

Glyphosate, its formulations, and its metabolite AMPA induce oxidative stress in rodents and in vitro. The Task Force classifies glyphosate as probably carcinogenic to humans (Group 2A).

Cited bibliography:

14- De Roos AJ, Zahm SH, Cantor KP, et al. Integrative assessment of multiple pesticides as risk factors for non-Hodgkin s lymphoma among men. Occup Environ Med 2003; 60: E11.

6- McDuffi and HH, Pahwa P, McLaughlin JR, et al. Non-Hodgkin s lymphoma and specifi c pesticide exposures in men: cross-Canada study of pesticides and health. Cancer Epidemiol Biomarkers Prev 2001; 10: 1155-63.

7- Eriksson M, Hardell L, Carlberg M, Akerman M. Pesticide exposure as risk factor for non-Hodgkin lymphoma including histopathological subgroup analysis. Int J Cancer 2008; 123: 1657-63.

15- WHO / FAO. Glyphosate. Pesticides residues in food 2004 Joint FAO / WHO Meeting on Pesticides Residues. Part II Toxicological. IPCS / WHO 2004; 95-162. foodsafety / areas_work / chemical-risks / jmpr / en / (accessed March 6, 2015).

16- Bolognesi C, Carrasquilla G, Volpi S, Solomon KR, Marshall EJ. Biomonitoring of genotoxic risk in agricultural workers from five Colombian regions: association to occupational exposure to glyphosate. J Toxicol Environ Health A 2009; 72: 986-97.

(to read comments from the authors on organophosphate insecticides also classified here, go to the attached pdf)

IARC Standard Classification Compounds or physical factors evaluated by the IARC (International Agency for Research on Cancer) and classified into four groups, based on existing scientific evidence on carcinogenesis.

Group 1: carcinogenic to humans There is sufficient evidence to confirm that it can cause cancer in humans.

Example: asbestos, ionizing radiation.

Group 2A:Probably carcinogenic to humans There is sufficient evidence that it can cause cancer in humans, but it is currently inconclusive.

Example: PCB, formaldehyde.

Group 2B: Possibly carcinogenic to humans There is some evidence that it can cause cancer in humans but so far it is far from conclusive.

Example: glass wool, gasoline engine exhaust.

Group 3: It cannot be classified as to its carcinogenicity to humans. There is currently no proof that it causes cancer in humans.

Group 4: Probably not carcinogenic to humans There is sufficient evidence that it does not cause cancer in humans.


According to the new IARC-WHO classification, glyphosate is as carcinogenic as PCBs, formaldehyde, human papillomavirus (HPV) type 68 and urethane, all members of group A2 in terms of their ability to cause cancer in humans. Translation: Dr. Medardo Avila Vazquez, REDUAS.


Video: France: Studies suggest glyphosate not carcinogenic - Senator Medevielle (June 2021).