Chlorite in Drinking Water: Health Risks, Sources, and How to Remove It
Chlorite is an organic contaminant that may be present in public drinking water. The Environmental Agency (EPA) regulates chlorite, setting its Maximum Contaminant Level (MCL) at 1 mg/L. Understanding its presence helps consumers ensure their water meets safety standards.
Health Effects
Exposure to chlorite in drinking water can lead to health concerns such as anemia. Additionally, individuals consuming water containing chlorite may experience nervous system effects. It is important to monitor and limit exposure to avoid these conditions.
How Chlorite Gets Into Tap Water
Chlorite is primarily introduced into drinking water as a byproduct of the water treatment process. It forms when chlorine dioxide is used as a disinfectant to treat water. This disinfection byproduct is managed by public water systems to ensure safe levels at the tap.
How to Remove Chlorite From Your Water
The main method for addressing chlorite in drinking water is by adjusting the disinfection process at the water treatment plant. This is achieved by reducing the chlorine dioxide dose used during water treatment. Controlling this dosage helps maintain chlorite levels below the regulatory limit.
Should You Test Your Water?
Consumers can check their annual Consumer Confidence Report or search the WaterQ database to see if chlorite has been detected in their local water supply. For those using private wells, periodic water quality testing through a certified laboratory can confirm the safety of the water. You can also look up your local water system on WaterQ or check the Chlorite data page for reported levels in your area.
Frequently Asked Questions
Is Chlorite dangerous in drinking water?
Yes, chlorite can be harmful if consumed in concentrations above the standard level. It can cause anemia and has been associated with nervous system effects. Maintaining levels below the regulatory limit helps ensure the water is safe to drink.
How does Chlorite get into tap water?
Chlorite enters tap water as a byproduct when chlorine dioxide is used for disinfecting the water supply.
How can I remove Chlorite from my water?
Chlorite levels are typically controlled at the treatment facility by reducing the dose of chlorine dioxide used during the disinfection process.
Source: EPA National Primary Drinking Water Regulations and WaterQ National Database. For more contaminants, visit our contaminant library.
What actually removes chlorine taste and smell
This is the one problem where the cheap answer is the right answer. Any activated carbon filter certified to NSF/ANSI 42 removes chlorine taste and odor, and a $25 pitcher performs as well as a $1,000 system for this specific job. Do not let a chlorine smell be upsold into a whole-house purchase. Letting water sit uncovered in the fridge for a few hours also works, for free.
Works
- Basic activated carbon (NSF 42)Fixes taste and smell. Does not remove any health-regulated contaminant.
- Carbon certified for lead (NSF 53)The cheapest thing that genuinely removes lead, cysts and many VOCs.
- Reverse osmosis (NSF 58)The broadest removal available at home: arsenic, nitrate, fluoride, PFAS, TDS.
Will not fix this
- Ion-exchange water softener
- UV disinfection (NSF 55)
Options that carry the right certification
Ordered cheapest-adequate first. Prices are indicative bands and move often.
| Product | Certification | Upfront | Per year | |
|---|---|---|---|---|
| Brita Elite Pitcher FilterPitcher | NSF/ANSI 42 and 53 certified, including a lead reduction claim.Catch:No fluoride, nitrate or arsenic reduction. Not PFAS-rated. | $25–40 | $50–70 | Check price |
| PUR PLUS Faucet MountFaucet mount | NSF/ANSI 42, 53 and 401 certified, including lead.Catch:Slows flow noticeably and will not fit every faucet. No fluoride or nitrate claim. | $25–45 | $60–90 | Check price |
| Aquasana AQ-5200 Under-SinkUnder-sink | NSF/ANSI 42, 53, 401 and P473 certified.Catch:Carbon, not RO — no meaningful fluoride, nitrate or arsenic reduction. | $110–160 | $80–120 | 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 chlorine taste and smell.