Hidden Costs of GMO Crops: Herbicide Use and Associated Health Impacts

The safety of eating genetically engineered (GMO) crops, which can be found in most processed foods in the United States, is still up for debate. But often overlooked in discussions of the safety of GMOs are associated impacts of GMO cultivation on the environment and on public health due to increased application of herbicides.

Research to quantify the use of herbicides as the adoption of herbicide-tolerant GMO crops has grown finds increased use of associated herbicides such as glyphosate and increased occurrence of herbicide-resistant weeds. Using EPA and USDA data to analyze the rapid proliferation of GMO crops and associated herbicides in the United States, our results reveal the interdependent relationship between the seed and chemical industries that is fueling a crisis of weed resistance and an escalation in more potent herbicide use.

In an effort to fight the spread of glyphosate-resistant weeds, biotechnology companies have developed 2,4-D and dicamba-tolerant corn, soybeans and cotton. The USDA has approved these “next generation” crops for sale and planting despite widespread concern about the increased toxicity of these herbicides. This analysis indicates that burgeoning infestations of herbicide resistant weeds caused by the over-reliance on glyphosate for broad control of weeds will not simply be solved with the intensified use of older, more toxic herbicides like 2,4-D and dicamba. In fact, the increased use of these herbicides could have serious health impacts on farmers, farm workers and the public. 2,4-D has been linked to non-Hodgkin’s lymphoma and dicamba is a known carcinogen.

U.S. agriculture’s reliance on these older pesticides reveals an urgent need for a paradigm shift toward agricultural and chemical policies that more adequately foster public health and worker safety.