Arsenic in Obrien, CA Drinking Water
Arsenic data for Obrien, California · 89,628 residents · 1 ZIP code
Water monitoring in Obrien, California has logged Arsenic at detectable levels in recent sampling cycles.
Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-05-14
Arsenic in Obrien Tap Water
Arsenic has been detected in Obrien, California drinking water at a maximum level of 5.54 ppb — below the EPA MCL of 10 ppb.
This analysis covers 89,628 residents across 1 ZIP code in Obrien.
Obrien's overall water quality grade is C (66/100).
Is Arsenic in Obrien Water Safe?
Arsenic was detected in Obrien 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 filter can reduce arsenic levels further.
Arsenic Levels by ZIP Code
| ZIP Code | Arsenic Level | EPA Limit | Status |
|---|---|---|---|
| 96070 | 5.54 ppb | 10 ppb | OK |
Average arsenic level across Obrien: 5.54 ppb
Health Effects of Arsenic
- Increased risk of skin, bladder, lung, and kidney cancer
- Cardiovascular disease and type 2 diabetes
- Skin changes (darkening, thickening, lesions)
- Developmental effects in children exposed in utero
Health risk severity: High. Governed by the Arsenic Rule (2006).
How Arsenic Gets Into Drinking Water
- Natural deposits in rock and soil (especially in western U.S.)
- Runoff from orchards and glass/electronics production
- Historical use of arsenic-based pesticides
- Well water in areas with arsenic-rich geology
What to Do About Arsenic in Obrien Water
- Install a reverse osmosis (RO) system certified under NSF 58
- Adsorptive media filters (iron-based) can also reduce arsenic
- Have well water tested if on a private supply
- Boiling water does NOT remove arsenic — it concentrates it
Look for filters certified under NSF 53 / NSF 58 for arsenic removal.