Can Roundup Cause Cancer?
Glyphosate is highly effective at managing weeds—but is that all it does?
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Transcript
Glyphosate is an herbicide, and is the active ingredient in Roundup, a popular weed-killer.
It’s really effective in managing the growth of weeds and is used a lot in the production of food like fruits, grains, nuts, and vegetables.
Glyphosate was initially synthesized in 1950, but at the time, scientists weren’t sure how to use it, so it was set aside. In 1970, chemists working for Monsanto identified its herbicidal potential, and in 1974, Monsanto introduced Roundup, which quickly became the leading herbicide product worldwide. Since then, it’s played a central role in agriculture.
In the 21st century, though, concerns about glyphosate’s impact on the environment and human health led to studies about the chemical’s safety and use.
Many concerns about human health stemmed from a 2015 report by the World Health Organization (WHO) International Agency for Research on Cancer (IARC), which concluded that glyphosate is “probably carcinogenic.”
Although an evaluation from the EPA in 2020 concluded that cancer risk was low when products were used exactly as instructed, numerous lawsuits claiming that Roundup caused cancer have been filed against Monsanto, and in 2020, its parent company agreed to pay more than $10 billion to settle claims regarding Roundup. In February of 2026, the company paid a $7.25 billion settlement to resolve thousands of lawsuits in the U.S. claiming the company failed to warn people that Roundup could cause cancer.
Some ecological risks of glyphosate use are well-documented, like damage to non-target plants and herbicide resistance.
Other risks are still being studied, and these are things like:
- Effects on reproduction and neurological function
- Potential endocrine disruption
- Impacts on wildlife habitats
While more research is still needed to determine glyphosate’s exact impacts on wildlife and human health, its potential risks have led some countries and cities to restrict or completely ban its use altogether.
It’s really effective in managing the growth of weeds and is used a lot in the production of food like fruits, grains, nuts, and vegetables.
Glyphosate was initially synthesized in 1950, but at the time, scientists weren’t sure how to use it, so it was set aside. In 1970, chemists working for Monsanto identified its herbicidal potential, and in 1974, Monsanto introduced Roundup, which quickly became the leading herbicide product worldwide. Since then, it’s played a central role in agriculture.
In the 21st century, though, concerns about glyphosate’s impact on the environment and human health led to studies about the chemical’s safety and use.
Many concerns about human health stemmed from a 2015 report by the World Health Organization (WHO) International Agency for Research on Cancer (IARC), which concluded that glyphosate is “probably carcinogenic.”
Although an evaluation from the EPA in 2020 concluded that cancer risk was low when products were used exactly as instructed, numerous lawsuits claiming that Roundup caused cancer have been filed against Monsanto, and in 2020, its parent company agreed to pay more than $10 billion to settle claims regarding Roundup. In February of 2026, the company paid a $7.25 billion settlement to resolve thousands of lawsuits in the U.S. claiming the company failed to warn people that Roundup could cause cancer.
Some ecological risks of glyphosate use are well-documented, like damage to non-target plants and herbicide resistance.
Other risks are still being studied, and these are things like:
- Effects on reproduction and neurological function
- Potential endocrine disruption
- Impacts on wildlife habitats
While more research is still needed to determine glyphosate’s exact impacts on wildlife and human health, its potential risks have led some countries and cities to restrict or completely ban its use altogether.