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Basic Information about Glyphosate in Drinking Water

Glyphosate at a Glance

Maximum Contaminant Level (MCL) = 0.7 milligrams per Liter (mg/L) or 700 parts per billion (ppb)

Maximum Contaminant Level Goal (MCLG) = 0.7 mg/L or 700 ppb

Health Effects
Some people who drink water containing glyphosate in excess of the MCL over many years could experience problems with their kidneys or reproductive difficulties.

Drinking Water Health Advisories provide more information on health effects

Chemical Abstract Service Registry Number
1071-53-6

Sources of Contamination
Runoff from herbicide use

List of all Regulated Contaminants (PDF) (6 pp, 396K, About PDF)

EPA regulates glyphosate in drinking water to protect public health. Glyphosate may cause health problems if present in public or private water supplies in amounts greater than the drinking water standard set by EPA.

What is glyphosate?
Glyphosate is an organic solid of odorless white crystals.

Uses for glyphosate.
Glyphosate is a non-selective herbicide used on many food and non-food crops as well as non-crop areas such as roadsides. When applied at lower rates, it serves as a plant growth regulator. The most common uses include control of broadleaf weeds and grasses in: hay/pasture, soybeans, field corn; ornamentals, lawns, turf, forest plantings, greenhouses, rights-of-way.

If you are concerned about glyphosate in a private well, please visit:

What are glyphosate's health effects?
Some people who drink water containing glyphosate well in excess of the maximum contaminant level (MCL) for many years could experience problems with their kidneys or reproductive difficulties.

This health effects language is not intended to catalog all possible health effects for glyphosate. Rather, it is intended to inform consumers of some of the possible health effects associated with glyphosate in drinking water when the rule was finalized.

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What are EPA's drinking water regulations for glyphosate?
In 1974, Congress passed the Safe Drinking Water Act. This law requires EPA to determine the level of contaminants in drinking water at which no adverse health effects are likely to occur. These non-enforceable health goals, based solely on possible health risks and exposure over a lifetime with an adequate margin of safety, are called maximum contaminant level goals (MCLG). Contaminants are any physical, chemical, biological or radiological substances or matter in water.

The MCLG for glyphosate is 0.7 mg/L or 700 ppb. EPA has set this level of protection based on the best available science to prevent potential health problems. EPA has set an enforceable regulation for glyphosate, called a maximum contaminant level (MCL), at 0.7 mg/L or 700 ppb. MCLs are set as close to the health goals as possible, considering cost, benefits and the ability of public water systems to detect and remove contaminants using suitable treatment technologies. In this case, the MCL equals the MCLG, because analytical methods or treatment technology do not pose any limitation.

The Phase V Rule, the regulation for glyphosate, became effective in 1994. The Safe Drinking Water Act requires EPA to periodically review the national primary drinking water regulation for each contaminant and revise the regulation, if appropriate. EPA reviewed glyphosate as part of the Six Year Review and determined that the 0.7 mg/L or 700 ppb MCLG and 0.7 mg/L or 700 ppb MCL for glyphosate are still protective of human health.

States may set more stringent drinking water MCLGs and MCLs for glyphosate than EPA.

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How does glyphosate get into my drinking water?
The major source of glyphosate in drinking water is runoff from herbicide use.

A federal law called the Emergency Planning and Community Right to Know Act (EPCRA) requires facilities in certain industries, which manufacture, process, or use significant amounts of toxic chemicals, to report annually on their releases of these chemicals. For more information on the uses and releases of chemicals in your state, contact the Community Right-to-Know Hotline: (800) 424-9346.

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How will I know if glyphosate is in my drinking water?
When routine monitoring indicates that glyphosate levels are above the MCL, your water supplier must take steps to reduce the amount of glyphosate so that it is below that level. Water suppliers must notify their customers as soon as practical, but no later than 30 days after the system learns of the violation. Additional actions, such as providing alternative drinking water supplies, may be required to prevent serious risks to public health.

If your water comes from a household well, check with your health department or local water systems that use ground water for information on contaminants of concern in your area.

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How will glyphosate be removed from my drinking water?
The following treatment method(s) have proven to be effective for removing glyphosate to below 0.7 mg/L or 700 ppb: granular activated carbon.

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How do I learn more about my drinking water?
EPA strongly encourages people to learn more about their drinking water, and to support local efforts to protect the supply of safe drinking water and upgrade the community water system. Your water bill or telephone book's government listings are a good starting point for local information.

Contact your water utility. EPA requires all community water systems to prepare and deliver an annual consumer confidence report (CCR) (sometimes called a water quality report) for their customers by July 1 of each year. If your water provider is not a community water system, or if you have a private water supply, request a copy from a nearby community water system.

The CCR summarizes information regarding sources used (i.e., rivers, lakes, reservoirs, or aquifers), any detected contaminants, compliance and educational information.

Some water suppliers have posted their annual reports on EPA's Web site.

Other EPA Web sites

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