Antimony in Connecticut Drinking Water
By Alexander Snyder, Founder & Water Quality Data Lead
The U.S. EPA sets the legal limit (MCL) for Antimony at 0.006 mg/L, but the health-based safe level set by California's OEHHA is 0.001 mg/L. That health guideline is roughly 6x stricter than the federal legal limit.
Antimony has been detected in 53 Connecticut ZIP codes, above a limit or health guideline in 10. Here is what you need to know about antimony in your drinking water and how it may affect your household.
What Is Antimony?
Antimony is a metallic element that enters drinking water through discharge from petroleum refineries, fire retardant manufacturing, ceramics production, electronics, and solder. It also occurs naturally in some geological formations. The EPA maximum contaminant level is 6 parts per billion, while the California public health goal is 1 ppb. Chronic exposure at elevated levels may increase blood cholesterol and decrease blood sugar.
Is Antimony in Your Water?
Enter your Connecticut ZIP code to find out if antimony is in your local water — and see personalized health risks for your household.
Check Your ZIP CodeHealth Effects of Antimony
Increase in blood cholesterol; decrease in blood sugar
Safety Guidelines
Health Guideline
0.001 mg/L
Source: California OEHHA
Legal Limit (MCL)
0.006 mg/L
EPA Maximum Contaminant Level
Antimony's health-based safe level is roughly 6x stricter than the federal legal limit.
| Standard | Level | Source |
|---|---|---|
| EPA Legal Limit (MCL) | 0.006 mg/L | EPA |
| Health Guideline | 0.001 mg/L | California OEHHA |
| Gap | ~6x stricter than legal | |
Where Does Antimony Come From?
Discharge from petroleum refineries; fire retardants; ceramics; electronics; solder
How to Reduce Antimony in Your Water
- 1Install a point-of-use reverse osmosis system certified to NSF/ANSI Standard 58 for antimony reduction, which removes the majority of dissolved antimony from drinking water.
- 2Use an activated carbon block filter certified to NSF/ANSI Standard 53; verify that antimony is specifically listed on the filter's performance data sheet.
- 3Distillation units can effectively reduce antimony concentrations since the metal does not volatilize at the boiling point of water.
- 4Test your water through a certified laboratory to establish baseline antimony levels and retest after treatment installation to confirm reduction.
Who Is Most Vulnerable to Antimony?
The safe level of antimony varies significantly depending on who is drinking the water. CheckYourTap calculates adjusted safe levels for each member of your household:
A contaminant level that is safe for an adult may exceed guidelines for an infant by 4-8x or more. Check your ZIP code to see personalized results.
Reading this inside ChatGPT or Claude?
This page can tell you the general science, but not what is actually in your water’s antimony level — that depends on your exact address. You can get your specific answer two ways:
- Inside the chat: ask your assistant to “check my tap water with CheckYourTap”. Our connector returns your ZIP code’s measured contaminant levels — including the derived dog and cat safe levels — and, only if you ask it to, can email you the report or arrange a specialist callback.
- On the web: open CheckYourTap.com and enter your ZIP code for a free 30-second report.
Concerned about Antimony in your water?
Schedule to get your water tested for antimony and more — a Valiant water specialist will review your results and arrange testing for your home.
Frequently Asked Questions
Is Antimony in my tap water?▾
What level of Antimony is safe?▾
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Related Contaminants
Check Water Quality by ZIP Code
Sources
The legal limits and health guidelines for Antimony on this page come from the following public authorities:
About This Report
This water quality report is compiled from public records filed with the U.S. Environmental Protection Agency, state health departments, and the U.S. Geological Survey. Contaminant levels are evaluated against EPA federal standards and health-based guidelines from leading environmental and public health organizations. CheckYourTap is a service of Valiant Energy Solutions, a Connecticut water quality and energy services company established in 1930.
This report is general information, not medical advice or a substitute for certified laboratory testing. Talk to your pediatrician or physician about specific health concerns.
Reviewed by the CheckYourTap editorial team. Last updated July 2026