Oliver Moore: Report raises red flag over herbicides
The cause? A recent assessment by the World Health Organization’s specialised cancer agency, the International Agency for Research on Cancer (IARC). The IARC recently made the assessment that glyphosate “probably causes cancer”.
The IARC assessed the carcinogenicity of five organophosphate pesticides. The herbicide glyphosate and the insecticides malathion and diazinon were classified as “probably carcinogenic to humans (Group 2A).”
The insecticides tetrachlorvinphos and parathion were classified as “possibly carcinogenic to humans (Group 2B).”
The IARC used both animal and human studies to come to its conclusion on glyphosate. For the sake of clarity, the quotes below are taken directly from the publication itself, and not from the IARC press release or any other organisation’s press releases.
There was “limited evidence” from human studies of carcinogenicity. However in human studies from US, Canada and Sweden, they found “increased risks for non-Hodgkin lymphoma, which “persisted after adjustment for other pesticides”. These were in occupational settings — that’s people who handle or are in close proximity to it: farmers, farm workers, but also rural residents.
In animal studies, the evidence of carcinogenicity was stronger, and classified as “sufficient” by the IARC.
Glyphosate is the best selling and highest profile of these, used in over 750 products, including Roundup. Its use has increased since herbicide resistant GM crops were developed. However, it is widely used by many farmers and horticulturists, as well as public authorities and hobby gardeners alike. Indeed its wide use and popularity is what has made this such a story.
Monsanto, makers of Roundup, have called for the IARC paper to be retracted.
Monsanto said in its statement, “IARC has classified numerous everyday items in Category 2 including coffee, cell phones, aloe vera extract and pickled vegetables, as well as professions such as a barber and fry cook.”
However, as Tom Philpott, writing in Mother Jones, pointed out: “The IARC classified most of these items at the less dangerous 2B level, whereas glyphosate is in the ‘probably carcinogenic’ 2A category. Of Monsanto’s list, only emissions from high-temperature frying and the occupational exposure experienced as a barber are rated as 2A.”
Monsanto and others state no new research was presented by the IARC. They also pointed out that regulatory authorities approve glyphosate, and claim to have offered research to the IARC, which they refused.
Countering this, senior toxicologist Kathryn Guyton, one of the authors of the IARC publication, said in an interview in Nature that the IARC limits itself to peer-reviewed publications and government reports.
Indeed this issue — what sort of studies do authorities base decisions on — has been a contentious one for many years. The current EU approval process for glyphosate, which is likely to pass it safe, uses many unpublished industry reports. Critics claim that there are dozens of relevant independent studies excluded from the current EU approvals process.
A blind spot for the regulatory process is that there is no compulsion on industry to publish, or even just make available, studies they commission. This inevitably leaves authorities with partial information, and is one of the main drivers behind the #alltrials phenomenon — the push to have all commissioned trials published.
Until all data is made available to authorities, the public may well remain suspicious of the process. Meantime, Monsanto, whose share price dropped 2 percent following the news, and the pesticide industry in general, have certainly taken a hit. It is clear already however, that they are not taking it lying down.
