Nitrate in Drinking Water: Health Risks, Sources, and How to Remove It
Nitrate is an inorganic chemical compound that can contaminate drinking water supplies. The U.S. Environmental Protection Agency (EPA) has established a Maximum Contaminant Level (MCL) of 10 mg/L for this substance. Due to its potential for acute health risks, monitoring and managing its levels is highly important.
Health Effects
Ingesting high levels of nitrate can cause a decrease in the oxygen-carrying capacity of the blood. In infants, this reduced oxygen capacity can lead to a serious condition known as blue baby syndrome. It is crucial to address elevated levels promptly to protect vulnerable populations.
How Nitrate Gets Into Tap Water
Nitrate typically enters drinking water supplies from several agricultural and waste-related sources. Common origins include fertilizer runoff and septic tanks. Additionally, animal waste and effluent from sewage treatment facilities contribute to nitrate accumulation in water sources.
How to Remove Nitrate From Your Water
Several treatment methods can effectively remove nitrate from drinking water. These include ion exchange, reverse osmosis, and biological denitrification. Water treatment systems utilizing these technologies are commonly certified to reduce nitrate concentrations.
Should You Test Your Water?
You can check your local water utility's annual consumer confidence report or use the WaterQ search tool to see the nitrate levels in your area. For private well owners, regular testing is recommended to ensure concentrations do not exceed the EPA limit. You can also look up your local water system on WaterQ or check the Nitrate data page for reported levels in your area.
Frequently Asked Questions
Is Nitrate dangerous in drinking water?
Yes, nitrate can be dangerous in drinking water, particularly for infants. It can cause a condition known as blue baby syndrome by decreasing the oxygen-carrying capacity of the blood. Because of these acute health risks, keeping levels below the safety standard is highly critical.
How does Nitrate get into tap water?
Nitrate gets into tap water primarily through fertilizer runoff, septic tanks, animal waste, and discharges from sewage treatment plants.
How can I remove Nitrate from my water?
Nitrate can be removed from drinking water using treatment methods such as ion exchange, reverse osmosis, and biological denitrification.
Source: EPA National Primary Drinking Water Regulations and WaterQ National Database. For more contaminants, visit our contaminant library.
What actually removes nitrate
Nitrate is the contaminant where boiling actively hurts: it concentrates the nitrate as water evaporates, so the standard "boil it to be safe" instinct makes the problem worse. Carbon does not remove it and neither does a softener. Reverse osmosis at the tap, or whole-house anion exchange on a farm well, are the real options. If there is an infant in the house and your area has agricultural runoff, treat this as urgent.
Works
- Reverse osmosis (NSF 58)The broadest removal available at home: arsenic, nitrate, fluoride, PFAS, TDS.
- Anion exchangeWhole-house option for nitrate and uranium on well water.
Will not fix this
- Basic activated carbon (NSF 42)
- Carbon certified for lead (NSF 53)
- Ion-exchange water softener
- UV disinfection (NSF 55)
- Boiling Makes it worse — evaporation concentrates what's left behind.
Test before you buy.Nitrate can't be seen, tasted or smelled, and the right hardware depends on the concentration you actually have. A certified lab test costs a fraction of the wrong filtration system. Start with your local water quality report, and get a mail-in lab test if you're on a private well.
Options that carry the right certification
Ordered cheapest-adequate first. Prices are indicative bands and move often.
| Product | Certification | Upfront | Per year | |
|---|---|---|---|---|
| APEC ROES-50 EssenceUnder-sink | Built with WQA-certified components to NSF/ANSI 58.Catch:Needs an under-sink drain connection and a spare hole for the dedicated faucet. Strips minerals — some people dislike the flat taste. | $180–240 | $50–80 | Check price |
| AquaTru Countertop Reverse OsmosisCountertop | NSF/ANSI 42, 53, 58, 401 and P473 certified.Catch:Takes counter space and you refill a tank by hand. Wastes some water as brine, like all RO. | $400–500 | $80–130 | Check price |
| iSpring RCC7AK 6-Stage ROUnder-sink | WQA Gold Seal certified to NSF/ANSI 58.Catch:The alkaline remineralization stage adds minerals back, which slightly raises TDS readings — expected, not a fault. | $200–280 | $60–90 | Check price |
Certification listings change. Before buying, confirm the current listing for the exact model in the NSF certified products database — a manufacturer's marketing page is not a certification. WaterQ earns a commission on purchases made through these links at no extra cost to you; see our affiliate disclosure. This is general information, not medical or engineering advice.
For a full breakdown of certifications, running costs and the models worth considering, see our buying guide for nitrate.