skip to Main Content
Genotoxicity Assays Published since 2016 Shed New Light on the Oncogenic Potential of Glyphosate-Based Herbicides

Archived HHRA News Posts
  • HHRA-funded Dicamba study published in “agrochemicals”

    Dicamba and 2,4-D in the Urine of Pregnant Women in the Midwest: Comparison of Two Cohorts (2010–2012 vs. 2020–2022) Abstract Currently, there are no known human biomonitoring studies that concurrently examine biomarkers of dicamba and 2,4-D. We sought to compare biomarkers of exposure to herbicides in pregnant women residing in the US Midwest before and after the adoption of dicamba-tolerant soybean technology using urine specimens obtained in 2010–2012 from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be (N = 61) and in 2020–2022 from the Heartland Study (N = 91). Specific gravity-standardized concentration levels for each analyte were compared between the cohorts, assuming data are lognormal and specifying values below the LOD as left-censored. The proportion of pregnant individuals with dicamba detected above the LOD significantly increased from 28% (95% CI: 16%, 40%) in 2010–2012 to 70% (95% CI: 60%, 79%) in 2020–2022, and dicamba concentrations also significantly increased from 0.066 μg/L (95% CI: 0.042, 0.104) to 0.271 μg/L (95% CI: 0.205, 0.358). All pregnant individuals from both cohorts had 2,4-D detected. Though 2,4-D concentration levels increased, the difference was not significant (p-value = 0.226). Reliance on herbicides has drastically increased in the last ten years in the United States, and the results obtained in this study highlight the need to track exposure and impacts on adverse maternal and neonatal outcomes. Keywords: pesticide; exposure; 2,4-dichlorophenoxyacetic acid; human biomonitoring You can read the paper here.

  • Crop-killing Weeds Advance Across US as Herbicides Lose Effectiveness

    Farmers say they are losing their battle with weeds at a time when growers are grappling with inflation and extreme weather linked to climate change. Crop-killing weeds such as kochia are advancing across the U.S. northern plains and Midwest, in the latest sign that weeds are developing resistance to chemicals faster than companies including Bayer and Corteva  can develop new ones to fight them. In many cases weeds are developing resistance against multiple herbicides, scientists said. Read the Reuters report here.  Read an earlier post by the HHRA board chair on the problem of resistant weeds here.

  • Heartland Health Research Alliance logo Help Lead this Worthy Cause: The HHRA is Recruiting Board Members

    We are publicly recruiting for board positions to ensure that we move beyond our immediate networks and honor our ongoing commitment to creating a board that is diverse in its composition, inclusive in its culture, and equity-focused in its approach to how it views its mission, its work, and the communities it serves. Our board members are the fiduciaries who steer the HHRA toward a sustainable future by adopting sound, ethical, and legal governance and financial management policies, as well as by making sure the HHRA has adequate resources to advance its mission. The Heartland Health Research Alliance (HHRA) is a 501(c)(3) organization founded in 2020 and dedicated to creating a new future in which cultivating health is the priority of farming. Our mission is to help inform the decisions shaping agriculture by advancing research on the health effects of food and farming. The HHRA seeks to fill vacancies on its board with qualified volunteers who, in addition to the standard roles and responsibilities (see below) of a board member, will be active advocates and ambassadors for the organization. Preferred qualifications 1. Professional experience in public health, medical research, epidemiology, toxicology, or organic farming, 2. A network or experience, or both, that may facilitate grant seeking and fundraising. 3. Commitment to the scientific method and the integrity of research. Essential information 1. The board of the HHRA is a volunteer board. 2. Each term is for three years, to which members can be re-elected once. 3. The board meets four times a year via the Internet. Expectations The HHRA expects each board member to honor the HHRA values and mission, act in the best interest of the HHRA, prepare for the board meetings by reading the agenda and reports, participate in the board meetings, and identify personal and professional connections for HHRA fundraising, grant-seeking, and policy influence. Process 1. To apply to volunteer, please send your CV and a one-page cover letter providing your name, contact information, and a description of either which of the preferred qualifications (above) you will bring to the HHRA or how your unique qualifications can help the HHRA.  Send these materials to Russell K. King, HHRA executive director, at rking@hh-ra.org . 2. Qualified applications will be reviewed by the current board, which will vote on whether to seat a volunteer as a member. (The next board meeting is in February 2024.) 3. The recruiting process will remain open until all seats are filled. Standard board member duties 1) Board members should advance the mission of the organization Overall, spreading awareness for your mission will promote growth and empower your team to flourish in its work. 2) Board members should prepare for and attend board meetings Review the agenda in advance. Everyone should understand all matters on the agenda heading into the meeting. Participation in discussions is a big part of why you choose someone for a role on the board. Fulfilling these duties is part of acting in good faith for any board member. 3) Board members hire, set compensation for, support, and collaborate with the executive director Hiring and supporting the executive director is one of the most important board member responsibilities.  The executive director is the professional hired to as bring nonprofit leadership and operational expertise to the HRRA’s daily operations and to advice and educate the board on matters relating to nonprofit governance and operations, so this board role is crucial to the organization’s health. 4) Board members are responsible for recruiting new members Drawing on your professional and personal networks, seek new members who have needed skills and qualities that are missing from the current board. 5) Every board member must fulfill three specific core legal responsibilities. Duty of Care Attending meetings and actively participating. Communicating with the executive director and other board members. Following through on assignments.. Supporting programs. Duty of Loyalty Support HHRA’s mission. Be a loyal ambassador for HHRA’s cause. All activities and decisions should be in the best interest of the organization, not in the best interest of the individual board member. Support the HHRA executive director. Duty of Obedience Adhere to HHRA’s bylaws, policies, and board decisions.

  • Fairness and Trust in Organic Food Supply Chains

    From the British Food Journal Findings show that perceived distributional, procedural and interactional fairness mutually interact with the perceived trustworthiness of business partners and that both contribute to building personal, organisational and institutional trust. Qualitative data support the conceptual model and show that trust is a valuable relational resource that affects relationship quality and the willingness to collaborate and to take risks in times of uncertainty.   More here.

  • Heartland Study Methods Paper Published in Chemosphere

    A methods paper is about our flagship study is being published in Chemosphere, a peer-reviewed scientific journal published since 1972 by Elsevier. It publishes both original research and review articles in environmental chemistry.  We extend our thanks to the authors: Jessica Larose, Jean-François Bienvenu, Patrick Bélanger, Éric Gaudreau, Yunpeng Yu, and David M. Guise.  

Genotoxicity Assays Published Since 2016 Shed New Light on the Oncogenic Potential of Glyphosate-Based Herbicides

Jan 16th, 2023
Jan 16th, 2023
Genotoxicity Assays Published since 2016 Shed New Light on the Oncogenic Potential of Glyphosate-Based Herbicides

Is DNA Damaged When Applicators are Exposed to Glyphosate-Based Herbicides? An HHRA Scientist Wanders Deep in the Weeds

Glyphosate-based herbicides (GBHs) have been used since 1974. The first evidence that GBHs can damage DNA was published in the 1990s. By then, Monsanto had submitted to the US EPA and other regulators around 100 genotoxicity studies, 99 of which reported no evidence of a positive genotoxic response.

These ~99 negative studies, coupled with Monsanto-commissioned critiques of the design, quality, and interpretation of the relatively few published, positive assays, convinced regulators that glyphosate and GBHs were not genotoxic.

From 2000-2010 a few dozen more scientific papers reported a positive genotoxicity response following exposure to glyphosate or a GBH. Several dozen more assays have been published since, with over 70% reporting a positive response.

Despite substantial new evidence showing glyphosate and GBHs can damage DNA and do so through at least two mechanisms of action, EPA and other regulators have not budged from their early 1990s conclusion.

Why is This Important?

Because GBHs are by far the most widely and heavily applied pesticide in history. Worldwide and in the US, more people have and continue to apply GBHs than any other pesticide. A significant share of people applying Roundup or another GBH do so with small-scale, handheld spray equipment that sometimes leads to high levels of dermal exposure to spray solution.

Over 130,000 Americans who have applied Roundup brand GBHs are now suffering from non-Hodgkin lymphoma (HNL) and have sued Monsanto (now owned by Bayer) for damages because of the lack of warnings on Roundup labels, defective, unsafe product design, and inadequate label directions and requirements.

The Roundup-NHL litigation is ongoing, although over 90,000 of the 130,000+ cases have settled and resulted in over $11 billion in payments to individual plaintiffs.

Dozens, if not hundreds of new cases are bound to arise annually over the next two or more decades. Why? Because some 65,000 people are newly diagnosed with NHL each year, and some portion of them will be among the millions of people who regularly spray Roundup to control weeds around homes, gardens, schools, roadways, industrial facilities, canals, power lines, and farm fields.

Science on Trial

Courts and juries have been wrestling for six years now over whether Roundup is more likely than not to increase the risk of NHL among applicators who used the herbicide many times annually over several years.

The debate among dueling lawyers and experts varies from trial to trial, but a primary focus in all trials has been on whether available science supports a “more likely than not” connection between heavy Roundup use and NHL.

Big differences exist in how GBH manufacturers and the US EPA assess the capacity of glyphosate and GBHs to damage DNA (they both conclude it does not), compared to the International Agency for Research on Cancer (IARC) and many scientists not working for or on behalf of GBH manufacturers (it does damage DNA via at least two mechanisms of action).

Controversy over the safety of Roundup and other GBHs has stimulated new research. In the last seven years, 84 newly published assays have reported a genotoxic response following exposure to glyphosate or a GBH, while just six published assays have reported no evidence of such a response.

Genotoxicity Assays Published since 2016 Shed New Light on the Oncogenic Potential of Glyphosate-Based Herbicides

This is among the key findings in an open-access paper by Charles Benbrook, HHRA’s Executive Director, Robin Mesnage, and William Sawyer. “Genotoxicity Assays Published Since 2016 Shed New Light on the Oncogenic Potential of Glyphosate-Based Herbicides” was published in the new journal Agrochemicals on January 16, 2023.

Agrochemicals In The NewsAll three co-authors have worked with plaintiff attorneys on the Roundup-NHL litigation. This has helped them understand how and why the EPA and other regulators have thus far not acknowledged that the weight-of-evidence has now shifted.

As stated in the last sentence in the paper’s abstract, “In light of genotoxicity results published since 2015, the conclusion that GBHs pose no risk of cancer via a genotoxic mechanism is untenable.”

It can take a lot of new science to convince regulators to change a conclusion they have defended for 40 years. Will the new data reported in this paper draw regulators deep enough into the weeds to understand that GBHs do indeed pose cancer risk through genotoxic mechanisms of action?  Time will tell.

Back To Top