The Case for Banning Atrazine

Atrazine is one of the most used herbicides in the United States: Approximately 70 million pounds are used nationwide each year. It's a common contaminant of water bodies, including drinking water, and so dangerous to both people and wildlife that it has been banned in more than 60 countries across the world.

Numerous studies have provided overwhelming evidence linking atrazine to significant human health concerns, including increased risk of aggressive prostate cancer and reproductive problems.

Atrazine is also linked to declines of amphibians and fish. Exposure at levels as low as 0.1 parts per billion (ppb) has been shown to harm reproductive organ development in frogs, potentially leading to population-level impacts. The current allowable level of atrazine in human drinking water is 30 times higher, at 3 ppb.

The U.S. Environmental Protection Agency has determined that lakes, rivers, and streams are contaminated with dangerous levels of atrazine across one-eighth of the entire continental United States. A recent EPA proposal to reduce atrazine water pollution would be an enormous failure and only recover 1% of contaminated waterways to levels the agency considers safe.

What Is Atrazine?

After glyphosate, atrazine is the second-most widely used pesticide in the United States. The country uses around 70 million pounds of it over an area of roughly 60 million acres of U.S. soil every single year. About 99% of that is used on three agricultural crops: corn, sorghum, and sugarcane.

Nearly every drop of atrazine is used to make fuel additives, factory-farmed animal feed, and food that’s both ultra-processed and unhealthy. Almost all U.S.-grown corn and sorghum are used to make ethanol, animal feed, and high-fructose corn syrup. Sugarcane is mainly used as a sugar source for processed food.

Where Is Atrazine?

It’s in the water. Wherever atrazine is applied, it often runs off to pollute groundwater or the nearest river, lake, or stream. A U.S. Geological Survey study that analyzed more than 10,000 water samples from streams and drinking-water wells across the country found that atrazine was the most commonly found pesticide water contaminant in the United States.  

The EPA has found harmful levels of it in more than 11,000 U.S. watersheds, which encompass about one-eighth of the entire landmass of the continental United States — roughly 250 million acres. That includes 88% of Illinois and 84% of Iowa.

The extensive contamination of lakes, rivers, and streams where drinking water is sourced has led to atrazine contaminating the drinking water of 40 million Americans and at levels that exceed health guidelines in the water of 3 million Americans.

How Does Atrazine Harm Human Health?

Atrazine is an endocrine disruptor, meaning it disrupts the body’s hormonal processes.  In fact it’s the poster child of endocrine disruptors, demonstrated to affect at least half a dozen hormonal pathways in humans. Its most notorious harm is to human fertility: It’s designated by California as a reproductive toxin, linked to reduced sperm quality in men and irregular menstrual cycles and suppressed ovulation in women.

Atrazine is also linked to multiple birth defects in infants, such as gastroschisis, in which a child is born with their intestines protruding through their belly. It requires invasive surgery immediately after birth and a stay of weeks to months in the neonatal intensive care unit.

Researchers at the National Institutes of Health’s National Cancer Institute have linked atrazine to multiple cancers, including non-Hodgkin’s lymphoma and aggressive prostate cancer.

And yet the EPA has historically failed to protect the public from atrazine. In 2020 the agency discarded safety precautions mandated under the Food Quality Protection Act that were put in place decades ago to limit young children’s exposure to atrazine. The EPA also reduced the protection factor that converts toxicity in rat and mouse studies to levels considered safe for humans — using a justification that relied solely on a model developed by atrazine’s primary manufacturer. These two actions now allow infants to be exposed to atrazine levels 30 times higher than those considered safe before.

How Does Atrazine Harm Wildlife?

Because atrazine is an endocrine disruptor in people, it’s likely that every demonstrated effect on wildlife is rooted in hormonal dysregulation. Atrazine can harm amphibian fertility and sexual organ development at extremely low levels — levels that are commonly found in water bodies throughout the United States. Reproductive damage can cascade over time and lead to major population declines in just one or two generations. 

The EPA has found that levels of atrazine in water throughout the country are higher than concentrations known to harm amphibians and fish. Similarly, atrazine contamination of plants that birds and mammals eat can expose them to levels 22 times (for birds) and 198 times (for mammals) the amount of atrazine that will harm them.

The agency has also found that atrazine probably harms more than 1,000 of the United States’ most endangered plants and animals — or 56% of all endangered plants and animals in the country.

Where Has Atrazine Been Banned?

As of 2024 atrazine has been banned in 63 countries — a number that increases every year.

It was phased out entirely in the European Union in 2007 because of excessive groundwater contamination above 0.1 ppb — a level commonly exceeded in U.S. groundwater. Despite nearly 20 years of no atrazine use in the EU, this chemical is still the most common pesticide groundwater contaminant in the bloc.

As of 2024 these countries have banned atrazine:

Would a U.S. Atrazine Ban Affect the Food Supply?

Not in the slightest. The silver lining here is that atrazine isn’t used on food — it’s used on crops to make ethanol as a fuel additive, factory-farmed animal feed, and corn syrup and sugar for ultra-processed foods that medical professionals recommend omitting from our diets.

Even though the United States uses an enormous amount of atrazine annually, it’s important to know that only about half of corn acres are treated with it each year — meaning the other half are growing just fine without it. The EU produces about 60 million tons of corn yearly without atrazine.

This chemical simply isn’t necessary to grow the crops it’s used on.

And there are a plethora of atrazine alternatives, both chemical and nonchemical. Economists have found that not only would getting rid of atrazine increase revenues for farmers — it would also have a minimal impact on prices of consumer goods.

Our Campaign

For decades the Center’s Environmental Health program has been fighting the nonsensical use of atrazine and its grave impacts on human health and wildlife. Multiple Center-led lawsuits and court wins spanning more than 10 years have forced federal agencies to put efforts into protecting wildlife and people.

Under the terms of a historic agreement reached with the Center, the EPA is starting to comply with the Endangered Species Act when approving pesticide use by assessing pesticides’ impact on endangered species. As part of that assessment, atrazine was found to likely harm more than 1,000 of the nation’s most endangered plants and animals — an essential first step to securing vital protections. Thanks to a Center lawsuit, a court later ordered the U.S. Fish and Wildlife Service to analyze atrazine’s impacts on all 1,700 U.S. plants and animals protected under the Endangered Species Act.

The Center and other public-interest groups sued the EPA over its decision to reapprove atrazine when it erased protections for young children and increased allowable levels in U.S. waterways. That legal case helped reduce the allowable levels of atrazine in water, and we will continue our campaign until the United States bans this pesticide for good. 

Check out our press releases to learn more about the Center’s actions against atrazine.