In Antelope, California, Radium has been detected in the public water supply — a contaminant that health agencies track because of documented effects associated with prolonged exposure at elevated concentrations.

Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-04-05

Radium in Antelope Tap Water

Radium has been detected in Antelope, California drinking water at a maximum level of 4.2 pCi/L — below the EPA MCL of 5 pCi/L (combined Ra-226 + Ra-228).

This analysis covers 48,321 residents across 1 ZIP code in Antelope.

Antelope's overall water quality grade is C (63/100).

Is Radium in Antelope Water Safe?

Radium was detected in Antelope water but currently falls within EPA limits. However, some health organizations argue the EPA MCL may not be protective enough.

If you are concerned, a reverse osmosis or ion exchange filter can reduce radium levels further.

Radium Levels by ZIP Code

Average radium level across Antelope: 4.2 pCi/L

Health Effects of Radium

• Increased risk of bone cancer (radium accumulates in bones)
• The body treats radium like calcium, storing it in bones
• Lifetime cancer risk of ~1 in 10,000 at 5 pCi/L
• No safe threshold for radioactive contamination

Health risk severity: High. Governed by the Radionuclides Rule.

How Radium Gets Into Drinking Water

• Natural radioactive decay in underground rock formations
• Groundwater sources (especially deep wells)
• Mining and industrial waste
• Higher in regions with specific geology (Midwest, parts of South)

What to Do About Radium in Antelope Water

1. Reverse osmosis (NSF 58 certified) removes 90%+ of radium
2. Ion exchange (water softeners) can reduce radium
3. Point-of-use RO at kitchen tap is most cost-effective
4. GAC filters alone are NOT effective for radium

Look for filters certified under NSF 58 for radium removal.

Related

• Radium — National Overview
• California Water Quality
• Antelope Water Quality
• Check Your ZIP Code