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Dr. Robin Mesnage is a Research Associate in the Department of Medical & Molecular Genetics at King's College in London. For more on the importance and implications of this research, see our FAQ and  guest blog by pediatrician and HHRA Science Advisory Board member Dr. Michelle Perro.

Archived HHRA News Posts
  • Spraying Pesticides HHRA Answers DPR’s Call for Comments on Its “Roadmap” for Transforming Pest Management

    In a January 26, 2023 press release, the California Department of Pesticide Regulation (DPR) released a provocative report entitled “Sustainable Pest Management: A Roadmap for California.” The Roadmap report sets “ambitious goals and actions to accelerate California’s systemwide transition to sustainable pest management and eliminate prioritized high-risk pesticides by 2050.” Also by 2050, the Roadmap report envisions that “Sustainable pest management has been adopted as the de facto pest management system in California.” The report captures the ideas and input of a diverse stakeholder group that met over two years to help DPR, Cal-EPA, and the California Department of Food and Agriculture develop a comprehensive plan sufficient to transform agriculture in the State from often heavily-pesticide dependent management systems to systems grounded in pest-prevention, biological control, and reduced-risk biopesticides. The Roadmap identifies and addresses most of the factors shaping pest management systems in the State and calls for dozens of new research, education, training, and regulatory initiatives. In order to guide the implementation process, DPR requested comments from the public that were due March 13, 2023. In crafting HHRA’s comments, Chuck Benbrook and Mark Lipson drew on their decades of experience tracking and advising DPR on pesticide use and regulatory issues.

  • HHRA Paper Analyzes Pesticide Dietary Risk in Individual Samples of Foods

    One of the main sources of pesticide exposure is through  the diet. It is critically important to understand pesticide residues in foods and how dietary risks have changed over time. Over the last 20 years HHRA’s Executive Director Charles Benbrook has developed an analytical database that quantifies the relative risk posed by residues in the diet. Known as the Dietary Risk Index (DRI), this  system was created to help researchers compare risk levels across foods and pesticides, track changes in dietary risk over time, and assess the impact of where food is grown on residues and risk levels, as well as how production systems influence residues and risks (conventional versus organic). The DRI combines the results of United States and United Kingdom pesticide residue testing programs with data on food serving sizes and each pesticide’s chronic Reference Dose or Acceptable Daily Intake. Chronic DRI values are a ratio: the amount of residue in a serving of food relative to the maximum amount allowed by regulators. DRI values are a ratio: the amount of residue in a serving of food relative to the maximum amount allowed by regulators. Data generated by the DRI helps guide HHRA’s policy and public health by highlighting which food-pesticide combinations account for the most worrisome risks in the food supply. The DRI system initially reported aggregate values for a given food/pesticide combination. These values are derived from multiple individual samples of a food collected by regulatory agencies.  For these DRI values, each individual number represents many servings of a given food. In 2022, HHRA added additional functionality the the DRI to report dietary risk in individual samples of a given food. The paper “Tracking pesticide residues and risk levels in individual samples—insights and applications,” which was published in the peer-reviewed journal Environmental Sciences Europe in July 2022, describes the methodology and data sources used to calculate these individual sample DRI values, and highlights some of the results and what they can tell us about residue levels in the global food supply. This is the first analytical system worldwide to provide this level of insight into residues in food. As the paper reports, “dietary risk levels are highly skewed. A large number of samples pose moderate, low, or very-low risks, and relatively few samples pose high or very-high risks.” Thus, regulators and researchers can use the DRI to pinpoint where pesticide dietary risks needs to be mitigated. Like all of HHRA’s peer-reviewed publications, this paper is open access and available free of charge. Click here to view the full text. Access DRI data here.

Archived Blog Posts
  • HHRA Earns Highest Rating from Guidestar/Candid

    By Russell K. King, executive director I’m pleased to announce that the HHRA has earned the Candid Platinum Seal of Transparency for 2023 –an achievement earned by fewer than one percent of US-based nonprofits. The Candid Platinum Seal is the highest level of recognition offered by Candid (formerly known as GuideStar) and is awarded to organizations that meet the highest standards of transparency and accountability. It’s an achievement that’s doubly important for the HHRA. The Candid Platinum Seal demonstrates the HHRA’s commitment to transparency and accountability. Our board, staff, volunteers, and partners believe that by sharing our data, metrics, and strategic priorities with the public, we can build trust and confidence in our organization and our work. To earn the Candid Platinum Seal, non-profit organizations must meet a rigorous set of criteria, including providing complete and accurate information about their mission, programs, finances, and governance on the Candid website, and sharing strategic priorities and information about outcomes. So why is this doubly important for the HHRA?  It’s important for all nonprofit organizations seeking grants and donations because the Candid Platinum Seal is a globally recognized acknowledgement that can inspire a higher level of confidence in the organization among potential grantors and donors–thereby making them far more likely to give. For the HHRA, however, it’s also important because our mission is one that relies on our credibility.  For our work to make a difference in people’s lives, people have to trust our processes, our findings, and our recommendations. The Candid Platinum Seal will help tell the world that, indeed, the HHRA is to be trusted. The leadership of the HHRA has always put integrity of the science first, which sets the HHRA apart in en era awash in willful misinformation and pseudoscience. I’ve long been a fierce advocate for the integrity in science, science reporting, and health information, so I’m proud to carry the torch that’s been passed to me. The HHRA supports researchers willing to seek answers to controversial questions. Our alliance of doctors, researchers, policy experts, and communicators works to answer questions that the government and private sector are too often unable or unwilling to address.  Through it all, we adhere strictly to scientific and ethical best practices to keep our research above reproach. The Candid Platinum Seal is an echo of the values that form the heart of the HHRA.  Let’s wear it with pride as we move forward.

  • Russell King | Executive Director Greetings from the New Executive Director

    By Russell K. King, HHRA Executive Director But yield who will to their separation,My object in living is to uniteMy avocation and my vocationAs my two eyes make one in sight. Robert Frost’s sentiment rang in my ears as I considered adopting the HHRA’s mission as my own. Why, after more than 25 years as a nonprofit CEO, would I take on a challenge of this complexity? Typically, when evaluating a potential professional challenge, you compare the attributes and experiences needed with those you possess. If they align sufficiently, it’s a good omen. I’ve spent more than a decade leading nonprofit organization through transitions, including a foundation that funded scientific research and two associations of medical professionals. I’ve created two development programs and led four others. And I’ve shared my expertise in nonprofit governance and policy, communications, and servant leadership. This constellation of what HHRA needs and what I can offer suggested that this was the direction I should follow. But there was something more. That something echoed Frost’s lines above: The chance to unite that which I enjoy, that which is most meaningful to me, with my work, thus uniting “my avocation and my vocation.” The two principles that have driven both my personal and professional lives have been: 1) we best find our way via the rigors and integrity of the scientific method, and 2) we create the richest meanings for our lives when we strive to help others. The HHRA, using science to improve and protect human health, rings both those bells with vigor. So here I am, eager to help the HHRA build on its illustrious beginnings and move to its next stage of development and growth. I will, of course, need your help. I won’t be shy about asking for it; please don’t be shy about offering it. This mission will require our collaboration, cooperation, and coordination. It will present moments in which we must support, encourage, and inspire each other. Worthy missions always do. For me, it’s the worthiness that matters most. Again, as Frost noted, we do this because it’s the right thing to do: Only where love and need are one,And the work is play for mortal stakes,Is the deed ever really doneFor Heaven and the future’s sakes.

  • A man spraying pesticides California’s Bold Plan to Transform Pest Management Systems is Long on Ambition and Light on Details

    By: Chuck Benbrook, HHRA ED By: Mark Lipson, HHRA Director of Policy and Regulatory Engagement We welcomed the invitation from California’s Department of Pesticide Regulation for members of the public to offer comments and guidance as the State begins to take concrete actions needed to achieve the goals set forth in the new report Sustainable Pest Management: A Roadmap for California. Reviewing the 94-page Roadmap report reminded us how many constituencies, forces, and factors are pushing and pulling farmers, pest managers, and government agencies in multiple directions that are rarely aligned. This Roadmap document describes a very different pest management future that will hopefully become the “de facto” way pests are managed on and off the farm by 2050. If successful by 2050, prevention-based biointensive Integrated Pest Management (bioIPM) will be the norm and there will be minimal if any use of high-risk “Priority Pesticides”. Some thirty-two years ago, DPR hired Chuck Benbrook to carry out a comprehensive evaluation of DPR’s programs and policies to assist in the integration of DPR into the newly-formed Cal-EPA. The resulting report, Challenge and Change: A Progressive Approach to Pesticide Regulation in California, came out in March of 1993. It provides dozens of recommendations intended to do many of the same things that the 2023 Roadmap report hopes to bring within reach. The fact that most pest management systems in California have become more, not less reliant on pesticides over the last 30 years suggests that DPR’s and CDFA’s efforts to achieve Roadmap goals are going to entail heavy lifting, mostly uphill. For this reason in HHRA’s comments, Mark and Chuck describe the nature and substantial scope of changes in laws and policy that will be required to track progress toward Roadmap goals and hopefully, someday, achieve them.

Guest Blog: Dr. Robin Mesnage on Groundbreaking Glyphosate-Microbiome Study

Jan 26th, 2021
Dr. Robin Mesnage is a Research Associate in the Department of Medical & Molecular Genetics at King's College in London. For more on the importance and implications of this research, see our FAQ and  guest blog by pediatrician and HHRA Science Advisory Board member Dr. Michelle Perro.

By: Robin Mesnage, PhD

Our gut is home to trillions of bacteria which are critical to good health. Because the once-in-a-century herbicide glyphosate can kill bacteria in a petri dish, the notion that glyphosate acts as an antibiotic in the human gut, and as a result is causing human disease, has gained prominence. However, whether and how glyphosate affects the gut microbiome is still an open question. It is what prompted me a few years ago to switch my research focus to the study of the effect of glyphosate on the gut microbiome.

Together with my group leader Dr. Michael Antoniou at King’s College London, we have put together an international team of scientists based in London, France, Italy, and the Netherlands. We have carried out the first in-depth animal study on the impact of glyphosate on the gut microbiome. After three years spent conducting the experiment and crunching numbers on glyphosate’s impacts on the rat microbiome, our findings have been published in Environmental Health Perspectives the 27th of January, 2021.

The Microbiome and Gut-Brain Connection
The gut microbiome contains billions of cells that we are learning play an important role in our physical, and even mental, health.

Let’s dive into our results. First, did glyphosate act as an antibiotic? The short answer is no. In order for glyphosate to act as an antibiotic, it needs to cause a significant shortage in the production of compounds in bacteria called aromatic amino acids. This is how glyphosate kills plants. More specifically, it interrupts a series of chemical reactions within the shikimate pathway.

We reveal for the first time that glyphosate does inhibit the shikimate pathway in the rat gut microbiome. However, glyphosate likely did not kill bacteria via its impact on the shikimate pathway, because bacteria do not need the shikimate pathway to get the aromatic amino acids they need. Like us, they get them from the food we eat.

Glyphosate’s impact on the shikimate pathway had other consequences. A multitude of small molecules (metabolites) accumulated, while others were depleted in the rat gut. The bacterial composition of the gut microbiome also changed, with some bacteria present at higher levels in the glyphosate exposed animals.

We have an explanation for this: the glyphosate molecule contains one atom of phosphorus, and it is very likely that this phosphorus was used as a source of energy by some bacteria to proliferate in the rat gut. It is not clear whether the changes caused by glyphosate in the gut were pathological. However, these changes are a reflection of impacts that can serve as a biomarker to detect whether glyphosate is having an effect on the gut microbiome in humans.

We had another important question to answer: did glyphosate’s impact in the gut stay in the gut? We evaluated this by tracking whether the changes in gut microbiome chemistry caused changes in blood composition.

The compounds altered as a consequence of the interruption of the shikimate pathway by glyphosate in the gut were mostly unchanged in blood. However, other chemicals had their levels disrupted by glyphosate, with some indicating that glyphosate caused oxidative stress.

Roundup Bioflow is the predominant glyphosate formulation in Europe.

Oxidative stress is produced when free radicals are created in such quantities that the body’s defense mechanisms are overwhelmed and cannot prevent damage to cells and DNA — the building blocks of our bodies. It is not fully clear if this oxidative stress is due to the action of glyphosate in the gut microbiome, although our results indicated that Roundup caused a depletion in protective compounds such carotenoids in the gut microbiome that could potentially explain this oxidative stress.

This oxidative stress was even more pronounced when we tested a commercial herbicide containing glyphosate called Roundup Bioflow (also known as MON 52276, the representative glyphosate herbicide in the EU that regulators are focusing on).

It is possible that the altered molecular profiles we observed could serve as a biomarker to better understand if oxidative stress is impairing the health of agricultural workers exposed to glyphosate.

What are the next steps? It is not clear whether the changes caused by glyphosate in the gut were pathological. This study is a first step, and we hope that our new findings will be used as a foundation by other scientists to make new studies.

We are conducting more studies at the moment to understand if this oxidative stress caused by glyphosate is also damaging DNA, and hence raising the risk of cancer. This work will progress through collaborations with The Heartland Study, the Heartland Health Research Alliance [click here to sign up for updates from HHRA], and the Ramazzini Institute. To be continued!


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