According to polls, the No. 1 reason people choose organic food is to avoid pesticide exposure.1 Not only do these chemicals threaten the environment, but they also pose a very clear and direct risk to human health.
Glyphosate, the active ingredient in Monsanto's Roundup herbicide, has made headlines because it's the most used agricultural chemical in history and because the International Agency for Research on Cancer (IARC) has identified it as a probable human carcinogen.
New Meta-Analysis Strengthens Link Between Glyphosate and Non-Hodgkin Lymphoma
A meta-analysis2,3,4,5,6 of six epidemiological studies published between 2001 and 2018 now adds further weight to such suspicions, showing glyphosate increases the risk of Non-Hodgkin lymphoma (NHL) — a group of blood cancers — by 41 percent in highly exposed subjects.
According to the research team, led by Luoping Zhang, a University of California, Berkeley toxicologist and a member of the Environmental Protection Agency's (EPA) scientific advisory panel (SAP) on glyphosate carcinogenicity,7 there is indeed a "compelling link" between glyphosate exposure and NHL.
Two other researchers on the team were also members of the EPA SAP that met in 2016. At the time, all three expressed concerns about the EPA's determination that glyphosate was "not likely to be carcinogenic" to humans,8 noting the EPA failed to follow proper scientific practices in its assessment of the chemical.9
Senior author professor Lianne Sheppard told Investigative journalist Carey Gillam,10 "It was pretty obvious they didn't follow their own rules. Is there evidence that it is carcinogenic? The answer is yes."
Evidence also emerged suggesting the EPA had colluded with Monsanto to protect the company's interests by manipulating and preventing key investigations into glyphosate's cancer-causing potential.
Of the six studies included in this new analysis, five showed a positive correlation. One of the studies, known as the Agricultural Health Study11 (AHS), published in 2018, found no effect.
However, the team points out that results were watered down in that study due to the inclusion of people with very low exposure. It's only when you look at high-exposure groups independently that a clear link between exposure and NHL emerges.
Scientists Convinced Glyphosate Is a Dangerous Carcinogen
These findings are bad news for Bayer, which now owns Monsanto and its toxic product line. At present, some 9,000 individuals have lawsuits pending against Monsanto-Bayer. All blame their NHL on Roundup exposure. In its defense, Monsanto has relied heavily on the AHS study's findings showing no correlation between exposure and NHL risk.
However, as noted in the new meta-analysis, published online February 10, 2019:12
"Using the highest exposure groups when available in each study, we report the overall meta-relative risk (meta-RR) of NHL in [glyphosate-based herbicide-exposed] GBH-exposed individuals was increased by 41 percent …
For comparison, we also performed a secondary meta-analysis using high-exposure groups with the earlier AHS (2005), and we determined a meta-RR for NHL of 1.45, which was higher than the meta-RRs reported previously. Multiple sensitivity tests conducted to assess the validity of our findings did not reveal meaningful differences from our primary estimated meta-RR.
To contextualize our findings of an increased NHL risk in individuals with high GBH exposure, we reviewed available animal and mechanistic studies, which provided supporting evidence for the carcinogenic potential of GBH.
We documented further support from studies of malignant lymphoma incidence in mice treated with pure glyphosate, as well as potential links between GBH exposure and immunosuppression, endocrine disruption, and genetic alterations that are commonly associated with NHL.
Overall, in accordance with evidence from experimental animal and mechanistic studies, our current meta-analysis of human epidemiological studies suggests a compelling link between exposures to GBHs and increased risk for NHL."
Sheppard told Sustainable Pulse,13 "Our analysis focused on providing the best possible answer to the question of whether or not glyphosate is carcinogenic. As a result of this research, I am even more convinced that it is." Gillam also quotes Sheppard, saying,14 "This paper makes a stronger case than previous meta-analyses that there is evidence of an increased risk of NHL due to glyphosate exposure. From a population health point of view there are some real concerns."