Glyphosate is unlikely to cause cancer: WHO/FAO committee

Glyphosate is unlikely to cause cancer to humans, says a report by a joint FAO and WHO committee on pesticides, but NGOs have questioned some of the scientists’ links to the chemical industry.

The publication, from the Joint Food and Agriculture Organisation (FAO) and World Health Organisation (WHO) Meeting of Pesticide Residues (JAMPR), comes just two days before the EU Standing Committee on Plants, Animals, Food and Feed is due to vote on whether or not to extend the pesticide’s licence in Europe, which will take place tomorrow (May18).

It also stands in contrast to the conclusions of the WHO’s International Agency for Research on Cancer (IARC) which said that glyphosate was a probable carcinogen.

Greenpeace has questioned the independence of the report. 

'Complementary not contradictory' to IARC conclusion

However a statement issued by WHO alongside the report pre-empted critical comparisons between the two. “The work by IARC and JMPR are different, yet complementary, and their respective functions can be seen as part of a continuum where potential hazards to public health are identified, and the level of risk associated with any such hazards is subsequently assessed.

“IARC reviews published studies to identify potential cancer hazards. It does not estimate the level of 'risk' to the population associated with exposure to the hazard. In contrast, JMPR reviews both published and unpublished studies to assess the level of health risk to consumers associated with dietary exposure to pesticide residues in food.”

The report said that overall there is "some evidence of a positive association" between glyphosate exposure and the risk of non-Hodgkin lymphoma in case-control studies and meta-analysis. "However, it is notable that the only large cohort study of high quality found no evidence of an association at any exposure level.”

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© iStock

It said the “overall weight of evidence” indicated that glyphosate and its formulation in different products is not associated with genotoxic effects at doses up to 2000 mg per kilo body weight by oral route – “the route most relevant to human dietary exposure”. It looked at studies conducted in mammals which are considered an appropriate model for assessing genotoxic risks to humans.

“The Meeting concluded that glyphosate is unlikely to be genotoxic at anticipated dietary exposures [and] that it was not necessary to establish an acute reference dose (ARfD) for glyphosate or its metabolites in view of its low acute toxicity.”

Glyphosate supplier Monsanto celebrated the report’s finding but slammed IARC’s classification as “inappropriate and inconsistent with the science on glyphosate”.

The company's vice president for global regulatory and government affairs, Phil Miller, said the FAO/WHO assessment was “rigorous” that reaffirmed the findings of regulatory agencies around the world that glyphosate is unlikely to pose a cancer risk.

Industry ties: Too close for comfort?

But the independence and impartiality of the report has been questioned by NGO Greenpeace. It says two key experts involved in the report – Alan Boobis and Angelo Moretto – both have ties to the International Life Sciences Institute (ILSI).  which is principally funded by private companies, including Monsanto, Dow and Syngenta – manufacturers of glyphosate.

The NGO also expressed concerns that much of the data used in the European Food Safety Authority’s (EFSA) assessment was kept secret as it was considered to be a trade secret, and that most of the scientists involved in the assessment preferred to remain anonymous.

According to Corporate Europe Observatory, Italian toxicologist Moretto was forced to resign from EFSA’S Pesticides Panel in 2011 for failing to declare his interests at ILSI.

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© iStock (Constantin Stanciu)

CEO says: “It doesn't mean that the JMPR conclusion would necessarily be wrong, but indicates that in any case JMPR's independence policy is even worse than EFSA's.”

Greenpeace EU food policy director Franziska Achterberg said: “The agencies contradicting the WHO cancer warning seem to either rely on officials who prefer not to be named, or lack a watertight policy to protect their impartiality. Any decision affecting millions of people should be based on fully transparent and independent science that isn’t tied to corporate interests."

The secrecy surrounding the data used by the Parma-based food safety agency was questioned by Commissioner for health and food safety Vytenis Andriukaitis, who wrote an open letter to the Glyphosate Task Force, a group of companies that want to see the herbicide renewed - requesting it to make public the studies used.

It responded by saying it would create physical reading rooms and, on an exceptional basis, copies of all 14 studies submitted to EFSA.

Last month, a non-binding resolution passed by the Parliament in Strasbourg approved the pesticide's re-authorisation for another seven years - rather than 15 as initially proposed - but demanded restrictions on its use by farmers just before harvesting crops.

The JMPR report also looked at the pesticides diazinon and malathion, giving both the green light.

It said diazinon is unlikely to pose a cancer risk to humans through dietary exposure and reaffirmed the ARfD of 0.03 mg/kg body weight, originally established by the JMPR in 2006 based on toxicity studies in rats.

Malathion is also unlikely to pose a carcinogenic risk to humans through the diet, it said, and reaffirmed the acceptable daily intake (ADI) of 0–0.3 mg/kg body weight.