A 2025 study published in Environmental Health provides some of the strongest evidence to date that glyphosate and glyphosate-based herbicides (GBHs) pose a significant cancer risk. The research reinforces the importance of organic agricultural practices for human health, which ban toxic synthetic herbicides. The two-year study tracked rats exposed to GBHs from pregnancy through adulthood, and found statistically significant dose-related increases in both benign and malignant tumors in several organs. The rats suffered from a range of cancers, including those of the blood, skin, liver, thyroid, ovaries, kidneys, bones, and mammary glands. Researchers found that almost half of leukemia-related deaths occurred in the first year, suggesting that GBH exposure early in life might be particularly dangerous.

Researchers exposed male and female rats to glyphosate and 2 GBHs, Roundup Bioflow [used in the European Union (EU)] and RangerPro [used in the United States (US)], starting on gestational Day 6 and continuing through 104 weeks of age. Even with doses equivalent to or lower than the EU’s current safety thresholds, cancer risk in the rats increased significantly. Commercial GBH formulations were found to be more carcinogenic than glyphosate alone, likely due to toxic co-formulants that intensify glyphosate’s absorption and effects. 

Glyphosate is presently the most widely used herbicide in the US, applied in both agricultural and public settings. The herbicide is applied to almost 90% of corn, soy, and cotton crops, as well as in orchards, vineyards, and public parks. The residue is pervasive and is frequently detected in food, water, and even breast milk. Organic farming, on the other hand, prohibits the use of toxic synthetic herbicides, including GBHs, offering a science-backed approach that reduces health risks for farmers and communities.  

As concerns about glyphosate’s health impacts continue to grow, this study highlights the protective power of organic agriculture and adds urgency to calls for stronger regulations and increased investment in organic agriculture research, infrastructure, and policy.