This web page is intended to provide more information on lithium because it is currently being monitored (2023-2025) in public water systems as part of the U.S. Environmental Protection Agency (EPA) Fifth Unregulated Contaminant Monitoring Rule (UCMR 51). EPA uses the UCMR to collect data on contaminants in drinking water that do not have standards. This data helps EPA determine whether future health research and/or regulation is needed. UCMR test results are available on Occurrence Data from the Unregulated Contaminant Monitoring Rule | US EPA. Water systems also must share information with customers about contaminants they detect.

Lithium is a metal that naturally occurs in rocks and soils and can sometimes be found in drinking water, mainly from the weathering of lithium-containing minerals in older bedrock or where groundwater interacts with saline water. Lithium in drinking water may also come from man-made sources related to the use of lithium and lithium salts in a wide variety of commercial products (including batteries, ceramics, glass, lithium-containing pesticides), industrial processes (including use as flux for welding and soldering, additive in aluminum electrolysis and concrete treatment), and as an oral medication for treating mental health conditions.

What is the federal standard for Lithium in drinking water?

Currently, lithium is not regulated in drinking water in the U.S., and there is no regulatory value against which to evaluate the lithium concentrations in drinking water. The EPA, under UCMR5 requires that certain drinking water utilities measure and report the concentrations of lithium in the drinking water supplies that they manage from 2023 to 2025.

What Health Effects Can Lithium Cause?

Our understanding of the potential health effects of lithium comes from its use over the past 75 years as the gold standard treatment for bipolar disorder2, making lithium one of the most well-studied medications to date.

Some people treated with lithium may experience gastrointestinal effects (nausea, diarrhea, and vomiting) and neurological effects (tremor). Long-term treatment may affect the thyroid, kidneys, and heart function.

Use during pregnancy is associated with increased risk of certain birth defects. Less is known about potential health effects from exposure to lithium in drinking water, where average daily intake levels are hundreds to thousands of times lower than that from medication.

How Else Can I be exposed to Lithium?

Most people are exposed to some level of lithium through their diet (primarily grains and vegetables) and drinking water. Daily intake from plant-derived foods and drinking water varies substantially worldwide. In adults in the US, daily intake ranges from 650 to 3100 micrograms.

Medicine prescribed for bi-polar disorder and other mental illness, natural background of lithium deposits in soils, septic system discharges, wastewater treatment discharges, and the significant increase in lithium battery manufacturing, recycling, and disposal could also be contributors.

Should I test my water for lithium?

For Public Water Supply customers: Please contact your local water utility to learn more about your drinking water and to see whether they have monitoring data for lithium or can provide any specific recommendations for your community.

For Private Well Owners: Testing your private well for Lithium is not recommended at this time. If you choose to test your well for Lithium, please note there are currently no laboratories in Connecticut which are certified for Lithium analysis. The CTDPH Environmental Laboratory Certification Program will update the certified lab list for lithium once labs complete the certification process.

CT DPH encourages private well owners to test their drinking water for general potability and other common naturally occurring and human-made contaminants. For general private well recommendations on what to test for, why and how often, refer to the CT DPH's website:

What should I do if I take Lithium as medication?

Individuals taking lithium therapeutically who know that lithium is in their drinking water should discuss the levels of lithium in their drinking water with their treating physician.

What is the Connecticut Department of Public Health (CTDPH) doing relative to Lithium?

The CT Department of Public Health (CTDPH) has identified a health-based drinking water value for lithium of 40 micrograms per liter (µg/L or parts-per-billion, ppb). This is the health-based comparison value used by the Agency for Toxic Substances and Disease Registry (ATSDR). ATSDR recommends that exposure to lithium be reduced when lithium levels in drinking water exceed 40 µg/L. CTDPH toxicologists will continue to evaluate the ATSDR value as additional scientific research on lithium is published in the peer-reviewed literature.

What Can I Do to Help Decrease Lithium Entering the Environment and Potentially the Water Supply?

Make sure you properly recycle any used lithium batteries. The Rechargeable Battery Recycling Corporation (RBRC), a non-profit public service organization made up of battery manufacturers and the products which contain rechargeable batteries, has established an infrastructure for the collection and recycling of all rechargeable batteries. By dialing 1-800-8BATTERY (822-8837) and entering the zip code, a resident will be directed to the nearest participating retail outlet. The RBRC website Call2Recycle | United StatesCall2Recycle | United States contains information for consumers on where to drop off rechargeable batteries for recycling.

Unused pharmaceuticals should never be flushed or poured down your sink or toilet. For more information on how to safely recycle these products please refer to the Resource link3.

What Treatment is Available to Remove Lithium from Drinking Water?

Reverse Osmosis (RO) and Ion Exchange (IX) resins have been shown to be effective at removing Li and other metals from drinking water.

What is the Agency for Toxic Substances and Disease Registry (ATSDR) and what is their affiliation?

“The Agency for Toxic Substances and Disease Registry (ATSDR), based in Atlanta, Georgia, is a federal public health agency of the U.S. Department of Health and Human Services. ATSDR protects communities from harmful health effects related to exposure to natural and man-made hazardous substances.4” They do this by responding to environmental health emergencies; investigating emerging environmental health threats; conducting research on the health impacts of hazardous waste sites; and building capabilities of and providing actionable guidance to state and local health partners.

Being a federal public health agency, the ATSDR is funded by the U.S. Congress. ATSDR is an independent operating agency within the Department of Health and Human Services. The Centers for Disease Control and Prevention (CDC) performs many of its administrative functions.


1US EPA: Fifth Unregulated Contaminant Monitoring Rule | US EPA

2Lithium | NAMI: National Alliance on Mental Illness

3Medicine Collections

4Agency for Toxic Substances and Disease Registry (

Connecticut Department of Energy and Environmental Protection:

Managing Household Batteries (

Medicine Collections

Product Stewardship

Contact Information:

For Questions on Emerging Contaminants in Public Drinking Water:

CT DPH – Emerging Contaminant Unit:

Phone: 860-509-7356


For Questions on Lithium in Private Wells:

CT DPH– Private Well Program

Phone: 860-509-8401


For Questions on Lithium and your health:

CT DPH – Environmental & Occupational Health Assessment Program:

Phone: (860) 509-7740