The widespread use of glyphosate, the active ingredient in the herbicide Roundup, is a significant concern for many consumers. While it is primarily used to control weeds, its application on certain crops, particularly for pre-harvest desiccation, leads to residues in our food supply. Understanding which foods are most likely to contain these residues is the first step toward making informed dietary choices.
Grains and Cereals: The Highest Risk Category
Glyphosate is very commonly sprayed on grains to accelerate the drying process, a practice known as pre-harvest desiccation. This dries the crops uniformly, making harvesting more efficient and allowing for earlier harvesting. As a result, many grain-based products often show detectable levels of residue.
Oats and Wheat
- Oats: Independent lab tests have repeatedly found glyphosate in a variety of oat-based products, including instant oatmeal, granola bars, and breakfast cereals. The Environmental Working Group (EWG) has reported finding glyphosate in popular products like Quaker Oats and various cereals.
- Wheat: Similarly, wheat crops are frequently desiccated with glyphosate, leading to residues in whole wheat bread, pasta, crackers, and other baked goods. This is a particularly concerning issue given how staple these foods are in many diets.
- Barley and Rice: Other cereal grains like barley and rice are also commonly treated with glyphosate, especially in conventional farming, and have been found to contain residues.
Legumes and Pulses: The Protein Source
Legumes and pulses are another food group susceptible to glyphosate residue due to pre-harvest desiccation. Testing by organizations like the Canadian Food Inspection Agency and the EWG has identified glyphosate in a high percentage of these products.
- Chickpeas and Lentils: Both chickpeas and lentils are dried with glyphosate before harvesting, which leads to residues. This is why hummus, which is made from chickpeas, has been found to contain high levels.
- Dry Edible Beans and Peas: Various types of dry edible beans and peas are also commonly treated, contributing to potential residue levels in these products.
Oilseeds and Nuts: Beyond Grains
Glyphosate is not exclusive to grains and legumes. It is also used in the cultivation of many oilseed crops and certain tree nuts, where it is used for weed control in orchards or fields.
- Soybeans: Genetically modified soybeans are specifically engineered to resist glyphosate, allowing farmers to spray the herbicide without killing the crop. This makes conventionally grown soy a major source of glyphosate residue.
- Canola: Similar to soy, canola is often grown as a genetically modified crop resistant to glyphosate.
- Almonds: Glyphosate is used for weed control in almond orchards, leading to potential contamination of the nuts. The Detox Project found almonds to be a food with particularly high exposure.
Fruits and Vegetables: Common Produce
While some sources mistakenly claim that glyphosate is not used on fruits and vegetables, it is applied for weed control in many orchards, fields, and vineyards, especially in non-organic agriculture.
- Apples and Grapes: Glyphosate is used for weed management in orchards and vineyards, which can lead to residues on the fruit.
- Berries: Crops like strawberries and blueberries can retain glyphosate residue, especially when sprayed for weed control.
- Sweet Potatoes and Carrots: Some root vegetables are also treated with glyphosate to clear weeds around them during their growth cycle.
A Comparison of Conventional vs. Organic Foods
One of the most effective ways to reduce dietary exposure to glyphosate is by choosing organic foods. Organic farming standards prohibit the use of synthetic herbicides like glyphosate, significantly minimizing the risk of contamination. Trace amounts can still occur due to drift from nearby conventional fields, but the difference in residue levels is substantial.
| Feature | Conventional Farming | Organic Farming |
|---|---|---|
| Herbicide Use | Uses synthetic herbicides like glyphosate for weed control and desiccation. | Prohibits the use of synthetic herbicides like glyphosate. |
| Glyphosate Residues | High probability of detectable residues, especially in grains and legumes. | Residues are extremely rare and typically only occur from environmental contamination (drift). |
| Harvesting Method | Often uses pre-harvest desiccation with glyphosate for uniform drying. | Employs natural methods for crop drying, avoiding chemical desiccants. |
| Cost | Generally lower cost due to higher yields and reduced labor. | Often higher cost due to more intensive labor and natural pest control methods. |
| Consumer Exposure | Higher potential for dietary exposure to glyphosate. | Significantly lower potential for dietary exposure to glyphosate. |
How to Reduce Glyphosate Exposure
Beyond simply choosing organic, consumers can take several proactive steps to limit their exposure.
- Check Labels for Certifications: Look for certifications like 'Glyphosate Residue Free' from third-party testing programs such as The Detox Project. These labels indicate that products have been tested for and contain no detectable glyphosate residue.
- Prioritize Problem Foods: If buying all organic isn't feasible, prioritize organic versions of the foods most likely to contain high levels of residue, such as oats, chickpeas, and wheat-based products.
- Wash Produce Thoroughly: Washing produce may help remove surface-level residues, though it is not a complete solution for systemic chemicals absorbed by the plant.
- Choose Whole Foods Over Processed: Processed foods often contain multiple ingredients sourced from conventional crops like corn and soy, increasing the likelihood of multiple sources of residue.
Conclusion
The practice of spraying glyphosate on various crops, particularly for pre-harvest desiccation, has led to widespread contamination of the food supply. Major sources of residue include grains like oats and wheat, legumes such as chickpeas and lentils, and a number of oilseeds, nuts, and even some fruits and vegetables. While regulatory bodies set maximum residue levels, independent testing has frequently detected higher levels in popular food products. Consumers can significantly reduce their exposure by opting for certified organic products, prioritizing organic versions of high-risk foods, and looking for third-party verified 'Glyphosate Residue Free' labels. Taking these steps empowers individuals to take control of their food choices and minimize potential health risks associated with this ubiquitous herbicide.
Visit The Detox Project for more research on glyphosate in food
Other Common Crops Sprayed with Glyphosate
Beyond the most common culprits, glyphosate is used on a wide variety of other crops for weed control, including alfalfa, citrus fruits, and some root and tuber vegetables. Its extensive use in agriculture and non-agricultural settings underscores the potential for environmental and dietary exposure. Awareness of its widespread application is key for understanding overall exposure risk.
The Role of GMOs
The development of genetically modified (GMO) crops resistant to glyphosate, such as specific varieties of corn and soy, has led to a dramatic increase in the use of the herbicide. This allows farmers to spray fields post-emergence without harming the crop, further contributing to residue levels in the food supply. The link between glyphosate and GMOs is a critical aspect of understanding why certain foods have higher residue levels.
