Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2019 Jul-Sep:781:186-206.
doi: 10.1016/j.mrrev.2019.02.001. Epub 2019 Feb 10.

Exposure to glyphosate-based herbicides and risk for non-Hodgkin lymphoma: A meta-analysis and supporting evidence

Luoping Zhang  1 , Iemaan Rana  2 , Rachel M Shaffer  3 , Emanuela Taioli  4 , Lianne Sheppard  5
Affiliations
Meta-Analysis

Exposure to glyphosate-based herbicides and risk for non-Hodgkin lymphoma: A meta-analysis and supporting evidence

Luoping Zhang et al. Mutat Res Rev Mutat Res. 2019 Jul-Sep.

Abstract

Glyphosate is the most widely used broad-spectrum systemic herbicide in the world. Recent evaluations of the carcinogenic potential of glyphosate-based herbicides (GBHs) by various regional, national, and international agencies have engendered controversy. We investigated whether there was an association between high cumulative exposures to GBHs and increased risk of non-Hodgkin lymphoma (NHL) in humans. We conducted a new meta-analysis that includes the most recent update of the Agricultural Health Study (AHS) cohort published in 2018 along with five case-control studies. Using the highest exposure groups when available in each study, we report the overall meta-relative risk (meta-RR) of NHL in GBH-exposed individuals was increased by 41% (meta-RR = 1.41, 95% confidence interval, CI: 1.13-1.75). For comparison, we also performed a secondary meta-analysis using high-exposure groups with the earlier AHS (2005), and we calculated a meta-RR for NHL of 1.45 (95% CI: 1.11-1.91), 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 publicly available animal and mechanistic studies related to lymphoma. We documented further support from studies of malignant lymphoma incidence in mice treated with pure glyphosate, as well as potential links between glyphosate / GBH exposure and immunosuppression, endocrine disruption, and genetic alterations that are commonly associated with NHL or lymphomagenesis. Overall, in accordance with findings 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.

Keywords: Carcinogenesis; Glyphosate; Meta-analysis; Pesticide; Ranger pro; Roundup.

PubMed Disclaimer

Conflict of interest statement

Declaration of Interest: All authors have no financial conflicts of interest to declare. We disclose Drs. Zhang, Taioli, and Sheppard served as Science Review Board Members of the US EPA FIFRA Scientific Advisory Panel (SAP) Meeting that evaluated glyphosate in December 2016.

Figures

Figure 1.
Figure 1.
Study Selection Process for Meta-Analysis using PRISMA Guidelines.
Figure 2.
Figure 2.
Major meta-analysis results. A) Forest plot for meta-analysis using AHS 2018 and B) using AHS 2005. C) Funnel plot for meta-analysis using AHS 2018 and D) using AHS 2005.
Figure 3.
Figure 3.
Timeline of glyphosate use milestones in relation to cohort and case-control study events. 1 Glyphosate active ingredient usage includes agricultural and non-agricultural applications 2 m = millions; Ibs = pounds 3 Completed by 63% of AHS participants
See this image and copyright information in PMC

References

    1. Thelin G, Stone W, Estimation of annual agricultural pesticide use for counties of the conterminous United States, 1992–2009: U.S Geological Survey Scientific Investigations Report 2013–5009, 2013.
    1. Benbrook CM, Trends in glyphosate herbicide use in the United States and globally, Environmental sciences Europe, 28 (2016) 3. - PMC - PubMed
    1. EPA, Glyphosate Reregistration Eligibility Document (RED). Glyphosate. EPA-738-R-93-014, U.S. Environmental Protection Agency, Washington, DC, 1993.
    1. EPA, Glyphosate; pesticide tolerances, in: Regul FRR. (Ed.), U.S. Environmental Protection Agency, Washington, DC, 2013, pp. 25396–25401.
    1. Wang Y, Jaw C, Chen Y, Accumulation of 2,4-D glyphosate in fish and water hyacinth, Water, Air and Soil Pollution, 74 (1994) 397–403.

Publication types