LithiumIn drinking water · contaminant reference
Also called Li.
Where it gets in
At the source
Comes from the source
In treatment
In the pipes
At your tap
- Legal limit
- None
- Health goal
- None
- Federal benchmark
- EPA health reference level (HRL) from the CCL 5 process, for screening only, not enforceable: 10 ppb
Values in parts per billion (ppb). Limits checked Oct. 4, 2026.
Where the rules stand
No federal MCL or health advisory. Lithium is on EPA's fifth Contaminant Candidate List and was monitored under UCMR 5. No NSF or WQA listing shows a lithium reduction claim. EPA says boiling does not remove it.
Is it in your water?
What EPA says about health
EPA's screening level is based on side effects in patients taking lithium as medicine, at far higher doses. These include kidney, nervous system and thyroid effects. EPA says exposure at or below 10 ppb is unlikely to raise health concerns. It cannot confidently estimate risk between 10 ppb and medicine-level doses.
Where it comes from
Lithium occurs naturally and can be higher in groundwater in dry parts of the western U.S. It is also used in batteries, medicine and industry.
What EPA found nationally
Under UCMR 5, EPA tested 9,949 utilities for Lithium. It was found at 3,621 of them, which report serving 108 million people. The highest single sample was 960 ppb.
| Utility | Highest sample | Found in |
|---|---|---|
| Waterpro IncDraper, UT · serves 33,100 | 960 ppb | 8 of 16 |
| Creekside Village MHPEsperance (T), NY · serves 115 | 921 ppb | 2 of 2 |
| Arizona Water Co - Apache JunctionApache Junction, AZ · serves 62,055 | 796 ppb | 4 of 4 |
| Aqua PA Water Co HonesdaleWhite Haven, PA · serves 5,500 | 702 ppb | 8 of 8 |
| Bermuda Water Company IncBullhead City, AZ · serves 25,000 | 580 ppb | 18 of 18 |
| Bernalillo Water SystemBernalillo, NM · serves 10,948 | 537 ppb | 4 of 4 |
| City of MesaMesa, AZ · serves 466,000 | 525 ppb | 70 of 70 |
| Indianola Water SupplyIndianola, IA · serves 15,833 | 480 ppb | 2 of 2 |
| Cal Am - OakhurstSacramento, CA · serves 3,693 | 474 ppb | 8 of 8 |
| City of Buckeye - Valencia Town DivisionBuckeye, AZ · serves 30,377 | 468 ppb | 2 of 2 |
| Highest single sample per utility, EPA UCMR 5 file of Aug. 27, 2026. One high sample is not a violation; compliance is judged on averages over time. | ||
What handles it
No NSF/ANSI reduction claim exists for Lithium, so no filter can be certified to remove it. Be wary of any product that says otherwise.
Sources
- The Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) Data Summary: July 2026 (EPA 815-S-26-007), U.S. EPA. Checked Oct. 4, 2026.
- Technical Fact Sheet: Lithium in Drinking Water (EPA 815-F-23-007, October 2023), U.S. EPA. Checked Oct. 4, 2026.
- Search for NSF Certified Drinking Water Treatment Units (standards and reduction claims lists), NSF. Checked Oct. 4, 2026.
- Find WQA Certified Products (Gold Seal listings by standard and claim), Water Quality Association. Checked Oct. 4, 2026.