Chuck Benbrook is an agricultural economist with a PhD in agricultural economics who has also farmed commercially. From 1979 to 1997 he worked on agricultural policy in Washington, D.C., including as executive director of the National Academy of Sciences' Board on Agriculture and of a House Agriculture subcommittee. He has spent more than 40 years researching farming systems, pest management, and pesticide regulation. For the past 25 years, Chuck has served as an expert witness in pesticide litigation involving glyphosate, chlorpyrifos, and paraquat. His 2025 paper proposes that glyphosate can persist in human bone. He is involved with the Heartland Health Research Alliance, which is running a Midwest birth cohort study on herbicide exposure. In this episode, John and Chuck discuss: Why weed control in 1996 often took three to five herbicides, and how Roundup Ready crops replaced that with one pass. How glyphosate use grew about 20-fold, reaching 80% of U.S. row crop acres at its peak. Why the first glyphosate-resistant marestail in 2004 started farmers on the herbicide treadmill. How seed and pesticide costs for corn, soybean, and cotton farmers have roughly tripled since 1996. Chuck's hypothesis that glyphosate binds to calcium and is stored in bone, then slowly released back into the blood. How Don Huber's work on glyphosate tying up minerals in soybeans helped Chuck connect the dots. Why pre-harvest desiccation is only 2-3% of glyphosate use but may drive about 90% of dietary exposure. How John uses boron as a maturity enhancer to replace a chemical desiccant and improve grain quality. Why Chuck believes current EPA toxicity testing misses chronic health effects, and what he would change. Additional Resources To read Chuck's paper on glyphosate persistence in bone, please visit: https://link.springer.com/article/10.1186/s12302-025-01057-1 To read Chuck's widely cited paper on trends in glyphosate use, please visit: https://link.springer.com/article/10.1186/s12302-016-0070-0 To read Chuck's widely cited paper on how genetically engineered crops changed pesticide use, please visit: https://link.springer.com/article/10.1186/2190-4715-24-24 To learn more about the Heartland Health Research Alliance, please visit: https://hh-ra.org To read about the Heartland Study, a Midwest birth cohort study on herbicide exposure, please visit: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-023-17171-9 To listen to John's conversation with Don Huber, please visit: https://advancingecoag.com/podcast/season-2-kickoff-with-don-huber/ Disclaimer: The views and opinions expressed by speakers on the Regenerative Agriculture Podcast are their own and do not necessarily reflect the views, positions, or policies of Advancing Eco Agriculture (AEA) or its employees. Appearances do not constitute an endorsement by AEA, and AEA does not guarantee the accuracy or completeness of statements made by guests. This podcast is for educational and informational purposes only and is not a substitute for professional agronomic, medical, legal, or financial advice. Always follow product labels and applicable laws, and consult a qualified professional before making decisions for your operation or your health. About John Kempf John Kempf is the founder of Advancing Eco Agriculture (AEA). A top expert in biological and regenerative farming, John founded AEA in 2006 to help fellow farmers by providing the education, tools, and strategies that will have a global effect on the food supply and those who grow it. Through intense study and the knowledge gleaned from many industry leaders, John is building a comprehensive systems-based approach to plant nutrition – a system solidly based on the sciences of plant physiology, mineral nutrition, and soil microbiology. Support For This Show & Helping You Grow Since 2006, AEA has been on a mission to help growers become more resilient, efficient, and profitable with regenerative agriculture. AEA works directly with growers to apply its unique line of liquid mineral crop nutrition products and biological inoculants. Informed by cutting-edge plant and soil data-gathering techniques, AEA's science-based programs empower farm operations to meet the crop quality markers that matter the most. AEA has created real and lasting change on millions of acres with its products and data-driven services by working hand-in-hand with growers to produce healthier soil, stronger crops, and higher profits. Beyond working on the ground with growers, AEA leads in regenerative agriculture media and education, producing and distributing the popular and highly-regarded Regenerative Agriculture Podcast, inspiring webinars, and other educational content that serve as go-to resources for growers worldwide. Learn more about AEA's regenerative programs and products: https://www.advancingecoag.com
