Glyphosate is a widely-used weed killer, exposure to which is associated with a number of health risks. Learn about where glyphosate is found and how to protect your family from exposure.
What is Glyphosate?
Glyphosate is a weed killer or herbicide. It is the most extensively used pesticide in the world today for both residential and agricultural purposes. Human exposure to glyphosate is widespread. We recommend avoiding glyphosate-based herbicides due to the mounting safety concerns.
What are the health risks?
Studies suggest a number of health risks associated with exposure to glyphosate. Children and fetuses are most vulnerable to pesticide exposures due to their developing organ systems and differences in the way they metabolize toxins. In addition, developmentally normal hand-to-mouth behavior, lack of dietary variety, close proximity to the ground where pesticides settle, and high respiratory rates result in higher exposures in children compared with adults.
- Cancer: Glyphosate is classified by the World Health Organization’s International Agency for Research on Cancer (IARC) as probably carcinogenic to humans based on strong evidence that it causes cancer in laboratory animals and some evidence that it increases cancer risk in humans.
- Hormone disruption: Studies have shown that glyphosate is an Endocrine Disrupting Chemical (EDC), meaning that it interferes with hormones in the body. EDCs can interfere with the development of the brain as well as the function of organ systems, such as the nervous and reproductive systems.
- Birth defects: Elevated rates of birth defects have been observed in animals fed with glyphosate-treated crops and in farming communities in areas where large quantities of glyphosate are used. Further research is needed to examine the link between glyphosate and birth defects.
- Nervous system toxicity: Laboratory studies suggest that glyphosate is toxic to the nervous system.
- Antibiotic resistance: Glyphosate has the potential to make bacteria less sensitive to antibiotics.
How are we exposed?
Glyphosate can be inhaled or ingested when it is applied to lawns and gardens. After application, we come into contact with glyphosate through plants, soil, air, and food. Glyphosate used on lawns and in parks can be tracked into our homes on shoes or strollers that have had contact with glyphosate-treated surfaces. Residues of glyphosate are detected on some produce as well as in processed foods.
How can I reduce exposure?
- Avoid using weed killers that list glyphosate as an active ingredient.
- Leave shoes, strollers, and wheeled luggage by the door in your home.
- Wash hands before eating and after spending time outdoors.
- Shop farmers markets and ask growers about their pesticide use or grow your own pesticide-free produce.
- Choose GMO-free foods labeled USDA Organic or Non-GMO Project Verified. Some GMO crops are engineered to be resistant to high amounts of glyphosate.
- Advocate for glyphosate bans in public spaces in your community.
- Encourage neighbors to avoid use of glyphosate-containing products.
How we’re studying glyphosate at Mount Sinai
Drs. Chen and Lesseur are investigating the impacts of glyphosate exposure during pregnancy in human cohorts and animal models. Utilizing data from Dr. Shanna Swan’s The Infant Development and Environment Study (TIDES), they found an association between glyphosate exposure during pregnancy and risk of pre-term birth. In the United States, complications that arise from pre-term births are a leading cause of infant mortality. In another study of TIDES participants, they found that girls born to mothers with higher glyphosate exposure during pregnancy had longer anogenital distance, a marker of testosterone exposure. This suggests that glyphosate interferes with hormones and may have additional impacts on development of reproductive organs and other hormone-dependent systems.
These findings are supported by a study that Drs. Chen and Lesseur conducted in rodents, where long-term exposure to glyphosate as well as the glyphosate-based herbicide Roundup was linked to hormone disruption. They found that prenatal glyphosate exposure at levels considered to be “safe” for human consumption was associated with longer anogenital distance in both male and female offspring, and an increase in thyroid stimulating hormone in males. These findings are further evidence of the endocrine disrupting properties of glyphosate.
In a separate rodent study, together with Institute member Dr. Lauren Petrick, Drs. Chen and Lesseur found that glyphosate increases homocysteine, a known risk factor for cardiovascular disease, and disrupts the gut microbiota. Decreased gut microbial diversity has been associated with a range of conditions including autoimmune diseases, obesity, diabetes, and autism spectrum disorder (ASD). More research is needed to investigate the links between glyphosate exposure, the gut microbiome, and health outcomes in children.