Agricultural Health Study Concludes Glyphosate Does Not Cause Cancer

NOVEMBER 14, 2017

The Journal of the National Cancer Institute (JNCI) has published a peer-reviewed study, “Glyphosate Use and Cancer Incidence in the Agricultural Health Study,” that finds no correlation between the popular herbicide and cancer.

The paper notes, “A previous evaluation in the Agricultural Health Study (AHS) with follow-up through 2001 found no statistically significant associations with glyphosate use and cancer at any site.” Further, “In this large, prospective cohort study, no association was apparent between glyphosate and any solid tumors or lymphoid malignancies overall, including NHL [non-Hodgkin lymphoma] and its subtypes.”

The study is significant because it is yet another study at odds with the International Agency for Research on Cancer’s (IARC) 2015 classification of glyphosate as “probably carcinogenic to humans,” noting strong mechanistic evidence and positive associations for NHL in some epidemiologic studies. The European Chemicals Agency, the European Food Safety Authority, Health Canada - Pest Management Regulatory Agency, the European Commission, and U.S. EPA previously have disputed IARC’s classification.

American Chemistry Council (ACC) president Cal Dooley said in statement, “It is unfathomable that IARC would ignore clearly relevant and critical data when evaluating the carcinogenicity of a substance. It demonstrates a high degree of negligence, misconduct and misuse of American taxpayer dollars. The omission of a JNCI-published study is yet another example of deeply rooted, systemic flaws in the IARC Monograph’s process and adds to the mounting evidence of blatant data manipulation, transparency issues and widespread conflicts of interest. IARC’s classifications have repeatedly misinformed and misguided both the public and policy-makers; they’ve lost all public trust and credibility, and a complete overhaul of the Monographs Program is overdue.”

Concerned with IARC’s review of glyphosate and its approach to chemical reviews generally, ACC launched earlier this year its “Campaign for Accuracy in Public Health Research” that seeks to promote “credible, unbiased and transparent science as the basis for public-policy decisions.”

ACC contends that IARC’s monographs program is plagued with process and scientific defects that ultimately leads to public confusion and ill-informed policy decisions. IARC’s conclusions can have significant ramifications for U.S. policy at the state and federal level, as many regulatory agencies make decisions predicated upon those classifications. For example, California’s Office of Environmental Health Hazard Assessment (OEHHA) lists Proposition 65 (Prop 65) chemicals based on IARC determinations. 

House Oversight and Government Reform (OGR) Committee Chairman Trey Gowdy (R-SC) previously sent a letter to National Institute of Health (NIH) Director Dr. Francis Collins, requesting production of documents and a briefing to explain why the National Cancer Institute (NCI) failed to publish data that showed no links between glyphosate and cancer. 

In his letter, Gowdy cited media reports indicating that an NCI epidemiologist, who led the IARC study of glyphosate, withheld key information and data.

The OGR Committee, prior to Gowdy’s letter, has been reviewing U.S. taxpayer funding of IARC. A 2016 letter by former Rep. Jason Chaffetz (R-UT) described IARC as having “a record of controversy, retractions, and inconsistencies.”