What Is Atrazine?
The EPA describes atrazine as a chlorinated triazine systemic herbicide used to control annual grasses and broadleaf weeds before they emerge, with its highest use on field corn, sweet corn, sorghum and sugarcane.
It is regulated in tap water. The EPA's national primary drinking water regulations set a maximum contaminant level of 0.003 milligrams per liter, or 3 parts per billion, for atrazine, name runoff from herbicide used on row crops as its source, and list cardiovascular system or reproductive problems as potential health effects from long-term exposure above that level. ATSDR says liver, kidney and heart damage has been observed in animals exposed to atrazine, and that it does not know if this would also occur in humans.
On cancer, ATSDR says the available information is inadequate to state definitely whether atrazine causes cancer in humans, and that an EPA-sponsored Cancer Assessment Review Committee classified atrazine as not likely to be carcinogenic to humans. The EPA released an interim registration review decision for atrazine in September 2020, and in July 2024 announced a revised level of 9.7 micrograms per liter at which atrazine is expected to adversely affect aquatic plants, to be used in a revised decision.
Sources checked September 15, 2026. Every point below links the page it came from.
The sources behind this answer
- Government sourceThe EPA describes atrazine as a chlorinated triazine systemic herbicide that controls annual grasses and broadleaf weeds before they emerge, with its highest use on field corn, sweet corn, sorghum and sugarcane. US EPA ↗
- Regulatory filingThe EPA's national primary drinking water regulations set a maximum contaminant level of 0.003 mg/L for atrazine and list runoff from herbicide used on row crops as its source. US EPA ↗
- Government sourceThe EPA's drinking water table lists cardiovascular system or reproductive problems as potential health effects from long-term atrazine exposure above the maximum contaminant level. US EPA ↗
- Regulatory filingThe EPA released its Interim Registration Review Decision for atrazine in September 2020, finalizing mitigation measures to protect human health and mitigate potential ecological risks. US EPA ↗
- Regulatory filingIn July 2024 the EPA announced a revised level of 9.7 micrograms per liter at which atrazine is expected to adversely affect aquatic plants, to be used in a revised regulatory decision. US EPA ↗
- Government sourceATSDR says liver, kidney and heart damage has been observed in animals exposed to atrazine, and it does not know if this would also occur in humans. ATSDR, CDC ↗
- Government sourceATSDR says available information is inadequate to state definitely whether atrazine causes cancer in humans, and that an EPA-sponsored Cancer Assessment Review Committee classified it as not likely to be carcinogenic to humans. ATSDR, CDC ↗
Sources checked September 15, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.