Orange County, CA

ZIP 90621

In ZIP 90621, 8 of the 12 things we check have at least one part graded D or F.

• Drinking water: City Of Fullerton has 2 contaminants at or over an EPA legal limit; 19 contaminants are above health goals, led by pfos at 15× California’s Public Health Goal.
• Nearest Superfund site: Mccoll, 1.5 miles away (3 within 10 miles).
• Largest share of modeled toxic air from industry: Recold (23%), mostly nickel.
• Fine particles (PM2.5) average 13.9 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 206,209 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 90621

• Superfund sites nearbyF
• Factories and industrial sitesF
• Oil and gas wellsF
• Parks and nature nearbyD to F
• Air qualityF
• Drinking water qualityF
• Pesticide useC to D
• Neighborhood health statusA to B
• Past wildfire impactsA to C
• Past flood impactsA
• Noise levelsA to D

Based on 9 census tracts · compiled September 10, 2026 · how each grade works and its sources

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