Radium in Los Angeles, CA Drinking Water
Radium data for Los Angeles, California · 2,384,216 residents · 95 ZIP codes
ZipCheckup's reading of Radium in Los Angeles, California: the highest detected level is 8 pCi/L; the EPA limit is 5 pCi/L (combined Ra-226 + Ra-228). Radium carries a high health-risk designation.
Because Radium is associated with health effects at sustained elevated exposures, residents in Los Angeles, California may find it useful that local water systems have returned detectable concentrations - facts that bear on long-term household water decisions.
Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-07-13
Radium in Los Angeles Tap Water
Radium has been detected in Los Angeles, California drinking water at a maximum level of 8 pCi/L — relative to the EPA MCL of 5 pCi/L (combined Ra-226 + Ra-228).
This analysis covers 2,384,216 residents across 95 ZIP codes in Los Angeles.
Los Angeles's overall water quality grade is B (77/100).
Is Radium in Los Angeles Water Safe?
Radium was detected in Los Angeles 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
| ZIP Code | Radium Level | EPA Limit | Status |
|---|---|---|---|
| 90001 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90002 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90003 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90004 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90005 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90006 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90007 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90008 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90009 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90010 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90011 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90012 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90013 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90014 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90015 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90016 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90017 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90018 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90019 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90020 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90021 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90023 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90024 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90025 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| 90026 | 8 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Not comparable |
| ...68 more ZIP codes |
Average radium level across Los Angeles: 8 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 Los Angeles Water
- Reverse osmosis (NSF 58 certified) removes 90%+ of radium
- Ion exchange (water softeners) can reduce radium
- Point-of-use RO at kitchen tap is most cost-effective
- GAC filters alone are NOT effective for radium
Look for filters certified under NSF 58 for radium removal.