What is atrazine?
Atrazine is a common herbicide used to kill weeds, mostly on farms (particularly in the Midwest on corn, sugarcane, and sorghum crops) but also on highway and railroad rights-of-way. Atrazine is an odorless white powder that dissolves in water. It does not occur naturally.
How can I be exposed to atrazine?
Most people are not exposed to atrazine on a regular basis. When applied as an herbicide to crops, atrazine can enter the air or wash into streams, rivers, or lakes. Atrazine can also move through soil and enter the groundwater. Surface water tends to have higher levels of atrazine than groundwater. Once atrazine enters water, it breaks down slowly and will stay there for a long time.
The risk of exposure is greatest for workers who may breathe, eat, drink, or touch atrazine during its chemical production or application as an herbicide.
The U.S. Environmental Protection Agency (EPA) classifies atrazine as a Restricted Use Product (RUP). This means that only certified users can purchase and use the chemical -- it is not widely available to the general population.
How can atrazine affect my health?
Atrazine can affect the reproductive system. Some studies found that exposure during pregnancy can increase the risk of:
- Premature birth
- Low birth weight
- Birth defects
Animal studies have shown that atrazine may also damage the liver, kidney, and heart.
Available information is insufficient to conclude that atrazine causes cancer in humans. While there are limited data to suggest a link between atrazine and certain types of cancer, the EPA has classified atrazine as not likely to cause cancer in humans.
What is the drinking water standard for atrazine?
The EPA and Massachusetts Maximum Contaminant Level (MCL) for atrazine is 0.003 milligrams per liter (mg/L).
In Massachusetts, local Boards of Health and Health Departments have the authority to regulate private wells. This may include setting criteria for their location, construction, water quality, and quantity. More information for residents who use private wells is available from the Massachusetts Department of Environmental Protection (MassDEP).
What are the testing requirements for atrazine?
In Massachusetts, public water systems are required to test for atrazine for four consecutive quarters (every three months for a year) and repeat every three years. Based on the results, testing may occur less often with approval by MassDEP.
Available data
Use the Explore drinking water data link on this page to access the following measures for atrazine in drinking water:
- Annual maximum concentration by number of Community Water Systems and people served
- Annual average concentration by number of Community Water Systems and people served
- Annual average concentration by Community Water System
- Quarterly average concentration by number of Community Water System and people served
MA EPHT presents data for the following geographies: city/town, county, EP region, or EOHHS region. Data are presented for public water systems only. The most current available data will be shown. Be sure to check the site periodically as new data are added.
Additional resources
Massachusetts
- MassDEP guide to water quality testing for private wells: Recommended water quality testing for private wells
National
- Agency for Toxic Substances and Disease Registry (ATSDR) ToxFAQs on atrazine: Frequently asked health questions about atrazine
- U.S. EPA atrazine updates: Information on atrazine’s federal status, information on FIFRA, and the EPA’s regular review process