Ozone 8-hour 4th-highest daily max
Ozone 8-hour 4th-highest daily max in New Haven County reached 0.075 ppm in 2024, 8% above the EPA NAAQS of 0.07 ppm.
County · TRI 2024
New Haven County, Connecticut Pollution
10 top TRI facilities tracked here. PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) fell meaningfully year over year (-24%). PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have more than halved since 2010.
FIPS 09009 · population 0
Anomaly engine
Notable Signals
Top facilities mapped
Where Chemicals Are Released In New Haven County
Each red dot is one of the top TRI facilities. Size reflects 2024 total releases. County boundary outlined in blue.
Pollutant pathways
New Haven County Pollutant Multi-Year Trends
PM2.5 annual mean (NAAQS 9 µg/m³ (annual))Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.
PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have more than halved since 2010.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour))Health riskFine inhalable particles 2.5 micrometers or smaller. They travel deep into the lungs and into the bloodstream — linked to asthma, heart disease, stroke, and premature death.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour)) concentrations have more than halved since 2010.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour))Health riskGround-level ozone (smog) forms when vehicle and industrial emissions react in sunlight. Inflames the airways, triggers asthma attacks, and worsens heart and lung disease.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour)) concentrations have fallen 10% since 2010.
NO₂ annual mean (NAAQS 53 ppb (annual))Health riskA tailpipe and combustion gas. Concentrates near busy roads and industrial sites; raises risk of airway inflammation, asthma, and lower respiratory infections in children.
NO₂ annual mean (NAAQS 53 ppb (annual)) concentrations have fallen 39% since 2010.
Lifetime cancer risk all pollutants (100 in a million (EPA elevated threshold))Health riskEPA-modeled added cancer cases per million residents from a lifetime of breathing local air toxics. EPA flags 100-in-a-million as elevated.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Formaldehyde ambient mean (0.077 µg/m³ (1-in-a-million URE))Health riskAn air toxic emitted by refineries, wood products, and combustion. EPA classifies it as a known human carcinogen — long-term inhalation raises cancer risk.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Benzene ambient mean (0.13 µg/m³ (1-in-a-million URE))Health riskAn air toxic from gasoline, refineries, and tobacco smoke. A known human carcinogen — chronic exposure is linked to leukemia and other blood cancers.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack)Health riskToxic chemicals reported by industrial facilities as released into the air — fugitive leaks plus smokestack emissions. Higher pounds means more inhaled exposure for nearby residents.
TRI air releases (5.1 fugitive + 5.2 stack) concentrations have more than halved since 2010.
TRI water releases (5.3)Health riskToxic chemicals reported by industrial facilities as discharged to surface waters (rivers, lakes, the ocean). Affects fishing, recreation, and downstream drinking-water intakes.
TRI water releases (5.3) volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
TRI land + off-site releasesHealth riskToxic chemicals released to land on-site or transferred off-site for disposal — landfills, deep-well injection, and similar. Risks groundwater contamination over time.
TRI land + off-site releases concentrations have more than doubled since 2010.
Greenhouse gases (GHGRP large emitters, through 2023)Health riskGreenhouse gases reported by large industrial emitters under EPA's GHGRP, in metric tons of CO₂ equivalent. Drives climate warming and the heat-related health effects that follow.
Greenhouse gases (GHGRP large emitters, through 2023) concentrations are roughly unchanged from 2010.
Top facilities · 2024
Where The Chemical Releases Are Concentrated
| Facility | City | Top chemical | Total releases | YoY |
|---|---|---|---|---|
| Waterbury Screw Machine Products CO INC | Waterbury | Copper compoundsHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 413k lb | — |
| Allnex USA INC. Wallingford Ct SiteAllnex USA INC | Wallingford | n-Butyl alcoholHealth riskEye and respiratory irritant; high exposure causes hearing loss and central-nervous-system effects. (NIOSH) | 89k lb | -26% |
| American Greenfuels LLCKolmar Americas INC | New Haven | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 74k lb | +34% |
| Ametek Specialty Metal Products DivAmetek INC | Wallingford | TrichloroethyleneHealth riskTCE. IARC Group 1 carcinogen — kidney cancer; suspected liver cancer and non-Hodgkin lymphoma. EPA MCL 5 µg/L; common DNAPL groundwater plume contaminant. (IARC, EPA, ATSDR) | 46k lb | +79% |
| Cpv Towantic Energy CenterCpv Towantic LLC | Oxford | AmmoniaHealth riskSevere respiratory and eye irritant; high concentrations cause chemical burns to lung tissue. (EPA) | 38k lb | +19% |
| Electric Cable Compounds INC | Naugatuck | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 36k lb | +71% |
| Safety-Kleen Systems INCClean Harbors INC | New Haven | Ethylene glycolHealth riskAcutely toxic if ingested. Metabolizes to compounds that cause kidney failure. (EPA) | 34k lb | +633% |
| Wieland Rolled Products N.A. - Waterbury FacilityWieland Holdings INC | Waterbury | DichloromethaneHealth riskIARC Group 2A probable carcinogen; central-nervous-system depressant; banned for most consumer paint-stripper uses. (IARC, EPA) | 25k lb | +39% |
| Unimetal Surface Finishing LLCUnimetal Surface Finishing LLC | Naugatuck | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 19k lb | -53% |
| Waterbury Plating Llc. | Waterbury | Nickel And Nickel CompoundsHealth riskNickel compounds are IARC Group 1 carcinogens; inhalation exposure raises lung and nasal cancer risk. (IARC) | 17k lb | +49% |
Superfund / NPL sites
Federal Cleanup Sites In New Haven County
Sites on EPA's Superfund National Priorities List, plus deleted sites whose cleanup objectives EPA has finalized. Federal-facility sites (defense, DOE, etc.) are flagged separately. Each link routes to a per-site page.
| Site | City | Status | Federal facility | Primary contaminant |
|---|---|---|---|---|
| Beacon Heights Landfill | Beacon Falls | NPL FINAL | No | 2-Butanone (Methyl Ethyl Ketone) |
| Laurel Park, Inc. | Naugatuck | NPL FINAL | No | 1,2-DichloroethaneHealth riskIARC Group 2B possible carcinogen; liver and kidney toxic. EPA MCL 5 µg/L. (IARC, EPA) |
| Scovill Industrial Landfill | Waterbury | NPL FINAL | No | AntimonyHealth riskInhaled antimony trioxide is an IARC Group 2B possible carcinogen; respiratory and cardiovascular effects from long-term exposure. EPA MCL 6 µg/L. (IARC, EPA) |
| Cheshire Ground Water Contamination | Cheshire | DELETED | No | 1,1,1-TrichloroethaneHealth riskMethyl chloroform. CNS depressant; ozone-depleting substance phased out under Montreal Protocol. EPA MCL 200 µg/L. (EPA, ATSDR) |
| Nutmeg Valley Road | Wolcott | DELETED | No | ManganeseHealth riskExcess inhalation can cause manganism, a Parkinson-like neurological disorder. (ATSDR) |
Equity context
County Population Characteristics
All block groups in New Haven County County, CT.
Demographic shares, national-percentile rankings (PM2.5, ozone, NO₂, diesel particulate, lead-paint risk, NPL/RMP/TSDF/NPDES proximity, drinking-water non-compliance), and EJ disparity scores will render here once the EJScreen-clone ingest completes for this geography. Why this section matters →
Browse
All 12 New Haven County Cities With TRI Data
Pollution trends and TRI 2024 pages for every tracked city in this county. Alphabetical.
- East Haven pollution· 2 facilities
- Guilford Center pollution· 1 facility
- Meriden pollution· 4 facilities
- Milford city (balance) pollution· 2 facilities
- Naugatuck pollution· 2 facilities
- New Haven pollution· 8 facilities
- North Haven pollution· 6 facilities
- Northford pollution· 1 facility
- Orange pollution· 2 facilities
- Wallingford Center pollution· 6 facilities
- Waterbury pollution· 11 facilities
- West Haven pollution· 2 facilities
Sources.
- EPA Toxics Release Inventory · retrieved 2026-05-07.
All sources are federal public-domain datasets under 17 USC §105. We aggregate but do not relabel; the underlying observations remain attributable to EPA.