Los Angeles County, CA

ZIP 91773

In ZIP 91773, 7 of the 12 things we check have at least one part graded D or F.

• Drinking water: Valencia Heights Water Co. has 2 contaminants at or over an EPA legal limit; 15 contaminants are above health goals, led by pfoa at 1,029× California’s Public Health Goal.
• Nearest Superfund site: San Gabriel Valley (area 2), 7.3 miles away (2 within 10 miles).
• Largest share of modeled toxic air from industry: Sterigenics-Ontario Facility (35%), mostly ethylene oxide.
• Fine particles (PM2.5) average 12.2 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 250,208 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 91773

• Superfund sites nearbyA to D
• Factories and industrial sitesD to F
• Oil and gas wellsA to F
• Parks and nature nearbyB to C
• Air qualityF
• Drinking water qualityC to F
• Pesticide useB to C
• Neighborhood health statusA to B
• Past wildfire impactsC to F
• Past flood impactsA to C
• Noise levelsA to D
• Radiation signalsC

Based on 15 census tracts · compiled October 25, 2026 · how each grade works and its sources

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