Suffolk County, NY

ZIP 11720

In ZIP 11720, 3 of the 12 things we check have at least one part graded D or F.

• Drinking water: Suffolk County Water Authority meets every EPA legal limit; 2 contaminants are above health goals, led by pfos at 2.1× California’s Public Health Goal.
• Nearest Superfund site: Bioclinical Laboratories, Inc., 4.3 miles away (3 within 10 miles).
• Largest share of modeled toxic air from industry: Long Island Sterilization (26%), mostly ethylene oxide.
• Fine particles (PM2.5) average 6.7 µg/m³; the WHO guideline is 5 and the EPA annual standard is 9.
• About 167,580 kg of agricultural pesticides are applied in the county each year.

Grades for ZIP 11720

• Superfund sites nearbyD to F
• Factories and industrial sitesB
• Oil and gas wellsA
• Parks and nature nearbyC to D
• Air qualityA to B
• Drinking water qualityC
• Pesticide useB
• Neighborhood health statusA to B
• Past wildfire impactsA
• Past flood impactsD
• Noise levelsA to C
• Radiation signalsA

Based on 11 census tracts · compiled October 25, 2026 · how each grade works and its sources

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