what is nitrate

8/10/2019 What is Nitrate

1/6

What is nitrate?

Nitrates and nitrites are nitrogen-oxygen chemical units which combine with various organic

and inorganic compounds.

Uses for nitrate.

The greatest use of nitrates is as a fertilizer. Once taken into the body, nitrates are converted to

nitrites.

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

EPA's private drinking water wells website

Water Systems Council website

What are nitrate s health effects?

Infants below six months who drink water containing nitrate in excess of the maximum

contaminant level (MCL) could become seriously ill and, if untreated, may die. Symptomsinclude shortness of breath and blue baby syndrome.

This health effects language is not intended to catalog all possible health effects for nitrate.

Rather, it is intended to inform consumers of some of the possible health effects associated

with nitrate in drinking water when the rule was finalized.

Top of page

What are EPA s drinking water regulations for nitrate?

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 nitrate is 10 mg/L or 10 ppm. 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 nitrate, called a maximum contaminant level (MCL), at 10 mg/L or 10

ppm. 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 II Rule , the regulation for nitrate, became effective in 1992. The Safe Drinking Water

Act requires EPA to periodically review the national primary drinking water regulation for each
http://water.epa.gov/drink/info/well/index.cfmhttp://water.epa.gov/drink/info/well/index.cfmhttp://www.watersystemscouncil.org/http://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://www.epa.gov/epahome/exitepa.htmhttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://www.watersystemscouncil.org/http://water.epa.gov/drink/info/well/index.cfm


2/6

contaminant and revise the regulation, if appropriate. EPA reviewed nitrate as part of the Six

Year Review and determined that the 10 mg/L or 10 ppm MCLG and 10 mg/L or 10

ppm MCL for nitrate are still protective of human health.

More information on the Six Year Review of Drinking Water Standards.

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

Top of page

How does nitrate get into my drinking water?

The major sources of nitrates in drinking water are runoff from fertilizer use; leaking from

septic tanks, sewage; and erosion of natural deposits.

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 amountsof 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.

EPA's Toxics Release Inventory (TRI) website provides information about the types and

amounts of toxic chemicals that are released each year to the air, water, and land.

Top of page

How will I know if nitrate is in my drinking water?

When routine monitoring indicates that nitrate levels are above the MCL, your water supplier

must take steps to reduce the amount of nitrate so that it is below that level. Water suppliers

must notify their customers as soon as practical, but no later than 24 hours 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.

See EPA's public notification requirements for public water systems.

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.

For more information on wells, go to EPA's website on private wells.

Top of page

How will nitrate be removed from my drinking water?

The following treatment method(s) have proven to be effective for removing nitrate to below 10

mg/L or 10 ppm: ion exchange, reverse osmosis, electrodialysis.
http://water.epa.gov/lawsregs/rulesregs/regulatingcontaminants/sixyearreview/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/regulatingcontaminants/sixyearreview/index.cfmhttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://www.epa.gov/tri/http://www.epa.gov/tri/http://www.epa.gov/tri/http://www.epa.gov/tri/http://www.epa.gov/tri/http://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/lawsregs/rulesregs/sdwa/publicnotification/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/publicnotification/index.cfmhttp://water.epa.gov/drink/info/well/index.cfmhttp://water.epa.gov/drink/info/well/index.cfmhttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/info/well/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/publicnotification/index.cfmhttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://www.epa.gov/tri/http://www.epa.gov/tri/http://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/lawsregs/rulesregs/regulatingcontaminants/sixyearreview/index.cfm


3/6

Top of page

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), detected contaminants, compliance and educational

information.

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

Other EPA websites

Find an answer or ask a question about drinking water contaminants onEPA's

Question and Answer websiteor call EPA's Safe Drinking Water Hotline at (800) 426-

4791

EPA Integrated Risk Information System

END

Nitrates (NO3) are an essential source of nitrogen (N) for plants. When nitrogen fertilizers are used toenrich soils, nitrates may be carried by rain, irrigation and other surface waters through the soil intoground water. Human and animal wastes can also contribute to nitrate contamination of ground water. InBenton and Franklin Counties, agricultural practices have been linked to elevated levels of nitrates indrinking water. Although any well can become contaminated by nitrates, shallow, poorly constructed, orimproperly located wells are more susceptible to contamination. Nitrate levels in drinking water can alsobe an indicator of overall water quality. Elevated nitrate levels may suggest the possible presence of othercontaminants such as disease-causing organisms, pesticides, or other inorganic and organic compoundsthat could cause health problems.

Who is at risk from high nitrates in drinking water?

The Environmental Protection Agency (EPA) has set the Maximum Contaminant Level (MCL) of nitrate asnitrogen (NO3-N) at 10 mg/L (or 10 parts per million) for the safety of drinking water. Nitrate levels at orabove this level have been known to cause a potentially fatal blood disorder in infants under six months ofage called methemoglobinemia or "blue-baby" syndrome; in which there is a reduction in the oxygen-carrying capacity of blood. The symptoms of blue-baby syndrome can be subtle and often confused withother illnesses. An infant with mild to moderate blue-baby syndrome may have diarrhea, vomiting, and/or
http://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#contenthttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://http/cfpub.epa.gov/safewater/ccr/index.cfmhttp://http/cfpub.epa.gov/safewater/ccr/index.cfmhttp://water.epa.gov/drink/contact.cfmhttp://water.epa.gov/drink/contact.cfmhttp://water.epa.gov/drink/contact.cfmhttp://water.epa.gov/drink/contact.cfmhttp://www.epa.gov/ncea/iris/index.htmlhttp://www.epa.gov/ncea/iris/index.htmlhttp://www.epa.gov/ncea/iris/index.htmlhttp://water.epa.gov/drink/contact.cfmhttp://water.epa.gov/drink/contact.cfmhttp://http/cfpub.epa.gov/safewater/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/lawsregs/rulesregs/sdwa/ccr/index.cfmhttp://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm#content


4/6

be lethargic. In more serious cases, infants will start to show obvious symptoms of cyanosis: the skin, lipsor nailbeds may develop a slate-gray or bluish color and the infant could have trouble breathing. Asample of the infants blood can easily confirm a diagnosis of blue -baby syndrome. It is difficult todetermine the true incidence of blue-baby syndrome in Washington State because it is not a reportabledisease.

Others at risk from excess nitrates in drinking water are:

Pregnant women

Individuals with reduced gastric acidity, and

Individuals with a hereditary lack of methemoglobin reductase.

In addition, some health studies have suggested that exposure to high levels of nitrates could lead tosome forms of cancer, but results are inconclusive

Testing recommendations:

The only way to know if your drinking water is contaminated with nitrates is to have it tested. If you own asingle family (domestic) well, it is recommended that you test your water every three years for nitrates;more often if you live in an area with a history of high nitrate levels or if someone in your home is at riskfrom nitrate contamination.

What to do if you have high nitrates in your drinking water:

If your drinking water sample tested above the MCL for nitrates and you or someone else in your home isat risk of developing health problems due to high nitrates, it is recommended that you do not drink thewater. Find a safe, alternative water supply until you decide on a more permanent solution.

There is no simple way to remove all nitrates from your water. Finding and correcting the source of nitratecontamination is the best course of action. Although it is common to think of boiling, softening or filtrationas a means of purifying water, none of these methods reduce nitrate contamination. In fact, boiling waterthat contains high nitrates can actually increase the nitrate concentration. Reverse osmosis, ion exchange

and distillation units could conceivably provide home treatment for removing nitrates from water, butthose processes can be complicated, expensive, and generally require routine maintenance. Activatedcarbon and other simple filters do not remove nitrates to any significant degree. Home treatment units aregenerally not recommended, particularly as a permanent solution to assure nitrate-free water for infantuse.

Your only long-term option may be to find a new source of water. This can be achieved by either drilling anew well or connecting to a public water supply system that has acceptable nitrate levels. When selectinga new well (or looking for sources of nitrate contamination around your existing well), be sure to consider


5/6

ALL possible sources of contamination. Unlike other contaminants, nitrates are not diluted and filtered outas water travels through soil, so water wells:

must be separated from possible sources of nitrate contamination, including both leaching andsurface drainage such as barnyard runoff.

should never be within 100 feet of a septic system, where an opportunity may exist for wastes to

enter the well. should have a sanitary seal specifically designed for the top of the well casing. This seal must be

correctly positioned, with all openings properly sealed, to disallow the entrance of any potentialcontaminant into the well casing and ultimately into the water source.

Nitrates In Drinking Water

Nitrates And Diet

Nitrate (NO 3) is a compound of nitrogen and oxygen found in nature and in manyfood items in our diet. Generally, the concentration of nitrates in the ground water is

low. The main adult human intake of nitrates is from food rather than from water.

Vegetables such as spinach, lettuce, beets and carrots contain significant amounts of

nitrate. Drinking water normally contributes only a small percentage of our total

nitrate intake.

Nitrates In Drinking Water

Although low levels of nitrates may occur naturally in water, sometimes higher levels,

which are potentially dangerous to infants, are found. Illinois has adopted a drinkingwater standard for nitrate of 10 milligrams per liter (10 mg/L) as N (nitrogen). This

standard is mandatory for public water supplies and is used as a guide for private

water supplies. The U.S. Environmental Protection Agency also uses 10 mg/L as N as

a mandatory national standard for public supplies under the Safe Drinking Water Act.

The 10 mg/L standard expressed as nitrogen (N) is equivalent to 45 mg/L expressed as

nitrate.

Sources Of High Nitrates

It is often difficult to pinpoint sources of nitrates because there are so manypossibilities. Sources of nitrogen and nitrates may include runoff or seepage from

fertilized agricultural lands, municipal and industrial waste water, refuse dumps,

animal feedlots, septic tanks and private sewage disposal systems, urban drainage and

decaying plant debris. Geologic formations and direction of ground water flow also

may influence nitrate concentration.

Health Problems


6/6

High nitrate levels in drinking water pose a health risk to infants because they may

cause methemologlobinemia, a condition known as blue baby syndrome.

High nitrate levels interrupt the normal body processes of some infants. Nitrate

becomes toxic when it is reduced to nitrite, a process that can occur in the stomach as

well as in the saliva. Infants are especially susceptible because their stomach juicesare less acidic and therefore are conducive to the growth of nitrate-reducing bacteria.

(Adults can consume large quantities of nitrates in drinking water or food with no

known ill effects; their stomachs produce strong acids that do not promote the growth

of bacteria that convert nitrate to nitrite.) Nitrite in the blood combines with

hemoglobin to form methemoglobin, which reduces the capability of the blood to

carry oxygen to all parts of the body. This results in the blue condition of the babys

skin.

Infants younger than 6 months of age are most susceptible. However, because of

individual differences in infants, some may not be affected. If an infant is affected, theskin turns a blue color, similar to the color of the blood vessels located close to the

skin. If a parent or other caregiver observes this condition, medical help should be

sought immediately. The infant is being asphyxiated because oxygen cannot be

transported by the blood. Prompt medical attention normally results in quick recovery

of the infant.

In all cases where drinking water contains more than 10 mg/L of nitrate as nitrogen,

an alternative source of water should be found for the infant. Boiling the water will

not reduce the nitrate concentration; in fact, it actually INCREASES the concentration

by evaporating off the water and leaving the nitrates behind. Water that is high in

nitrates should not be used for preparing infant formula or in any other way that could

result in consumption by a baby.

what is nitrate

Documents