St. Clair County, Illinois Pollution
10 top TRI facilities tracked here. PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) fell meaningfully year over year (-16%). PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 47% since 2010.
FIPS 17163 · population 256,791
Where Chemicals Are Released In St. Clair County
Each red dot is one of the top TRI facilities. Size reflects 2024 total releases. County boundary outlined in blue.
St. Clair 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 fallen 47% 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 fallen 44% 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 24% 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 38% 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 fallen 30% 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 are roughly unchanged from 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 have more than halved since 2010.
Where The Chemical Releases Are Concentrated
| Facility | City | Top chemical | Total releases | YoY |
|---|---|---|---|---|
| Veolia N.A. INC.Veolia North America | Sauget | Copper And Copper CompoundsHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 394k lb | -11% |
| Afton Chemical CorpNewmarket CORP | Sauget | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 223k lb | -4% |
| Occidental Chemical Corp Sauget PlantOccidental Petroleum CORP | Sauget | AmmoniaHealth riskSevere respiratory and eye irritant; high concentrations cause chemical burns to lung tissue. (EPA) | 68k lb | -5% |
| Solvay Fluorides LLCSolvay Fluorides LLC | East Saint Louis | Hydrogen fluoride | 11k lb | -11% |
| Flexsys America LP KrummrichFlexsys America L P | Sauget | Methyl isobutyl ketoneHealth riskEye, skin, and respiratory irritant; central-nervous-system depressant at high exposure. (NIOSH) | 8k lb | +14% |
| Brenntag Mid-South INC.Brenntag North America INC | East Saint Louis | Peracetic acidHealth riskStrong respiratory and eye irritant; corrosive at high concentrations. (NIOSH) | 7k lb | +26200% |
| Allnex USA INC.Allnex USA INC | East Saint Louis | Methyl methacrylateHealth riskSkin and respiratory sensitizer; can trigger occupational asthma and dermatitis. (OSHA) | 7k lb | +96% |
| Phillips 66 CO East St Louis TerminalPhillips 66 Co | Cahokia | Xylene (mixed isomers)Health riskEye, skin, and respiratory irritant; central-nervous-system effects from chronic exposure. (EPA) | 6k lb | +10% |
| Roho West | Belleville | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 4k lb | -50% |
| Kempen Paint CO | East Carondelet | Xylene (mixed isomers)Health riskEye, skin, and respiratory irritant; central-nervous-system effects from chronic exposure. (EPA) | 2k lb | -6% |
Federal Cleanup Sites In St. Clair 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 |
|---|---|---|---|---|
| Old American Zinc Plant | Fairmont City | NPL FINAL | No | ArsenicHealth riskIARC Group 1 carcinogen via inhalation and ingestion. EPA MCL 10 µg/L; chronic exposure causes skin, lung, bladder cancer and cardiovascular disease. (IARC, EPA, ATSDR) |
| Sauget Area 1 | Cahokia | PROPOSED | No | 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) |
| Sauget Area 2 | Sauget | PROPOSED | No | (4-Chloro-2-Methylphenoxy)Acetic Acid |
Who Lives In St. Clair County
All block groups in St. Clair County County, IL: 256,791 residents. County disparity score for pm2.5 (fine particulate) sits below the reference (89). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
- PM2.5 (fine particulate)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.65above the national median
- OzoneHealth riskGround-level ozone (smog) inflames the airways. Even short exposures trigger asthma attacks and worsen chronic lung and heart disease.62above the national median
- Nitrogen dioxide (NO₂)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.43near the national median
- Diesel particulateHealth riskSoot from diesel engines (trucks, trains, ports, construction). EPA classifies it as a likely human carcinogen and a major driver of childhood asthma near freight corridors.52near the national median
- Toxic releases (RSEI)Health riskEPA's Risk-Screening Environmental Indicators score — weights TRI chemical releases by toxicity, where they go, and how many people are nearby. Higher means greater modeled cancer and chronic-health risk.60near the national median
- Traffic proximityHealth riskPopulation-weighted distance to high-volume roads. Living close to heavy traffic raises exposure to PM2.5, NO₂, and diesel exhaust — and the cardiovascular and asthma risks that follow.52near the national median
- Lead-paint risk (pre-1960 housing)Health riskShare of housing built before 1960, when lead-based paint was common. Dust from deteriorating paint is the leading cause of childhood lead poisoning, which permanently impairs cognitive development.66above the national median
- Superfund site proximityHealth riskPopulation-weighted distance to NPL Superfund sites — the most contaminated waste sites in the country. Nearby groundwater, soil, and air can carry industrial solvents, metals, and other long-lived contaminants.84in the highest 20% nationally
- RMP-facility proximityHealth riskDistance to facilities holding chemicals at quantities large enough to require an EPA Risk Management Plan (refineries, fertilizer plants, etc.). These pose acute exposure risk during accidental releases.70above the national median
- Hazardous-waste site proximityHealth riskDistance to RCRA hazardous-waste handlers (treatment, storage, disposal facilities). Indicates potential exposure to industrial chemicals in air, soil, and groundwater.51near the national median
- Underground storage tanksHealth riskDensity of underground tanks (gasoline, heating oil, industrial fluids). Leaking tanks are a leading source of benzene and other volatile organic compounds in groundwater drinking-water supplies.79above the national median
- NPDES wastewater proximityHealth riskDistance to permitted industrial wastewater dischargers. Closer proximity raises exposure to pollutants released into surface waters used for fishing, recreation, and downstream drinking-water intakes.91in the highest 10% nationally
- Drinking-water non-complianceHealth riskEPA score for public water systems with health-based Safe Drinking Water Act violations. Higher means more residents on systems that recently exceeded safe limits for contaminants like lead, arsenic, or nitrate.76above the national median
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 89 | below the reference |
| Ozone | 91 | near the reference |
| Nitrogen dioxide (NO₂) | 66 | below the reference |
| Diesel particulate | 76 | below the reference |
| Toxic releases (RSEI) | 79 | below the reference |
| Traffic proximity | 72 | below the reference |
| Lead-paint risk (pre-1960 housing) | 79 | below the reference |
| Superfund site proximity | 66 | below the reference |
| RMP-facility proximity | 74 | below the reference |
| Hazardous-waste site proximity | 65 | below the reference |
| Underground storage tanks | 86 | below the reference |
| NPDES wastewater proximity | 118 | moderately above the reference |
| Drinking-water non-compliance | 3 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Co-Located Health Indicators
Modeled adult-prevalence estimates published by CDC PLACES, paired with this county's pollution and demographic context. Comparisons are ecological, not causal — pollution and disease prevalence covary at the area level, but the data does not attribute any individual's diagnosis to local exposure. How this section works →
Adult asthma (current)
CDC PLACES · 2025 release · BRFSS 2022-2023
COPD prevalence
CDC PLACES · 2025 release · BRFSS 2022-2023
Coronary heart disease
CDC PLACES · 2025 release · BRFSS 2022-2023
Diabetes (diagnosed)
CDC PLACES · 2025 release · BRFSS 2022-2023
Frequent mental distress
CDC PLACES · 2025 release · BRFSS 2022-2023
PLACES uses BRFSS-modeled small-area estimates, not individual records. Crude prevalence shown above is the local rate as published; comparators are age-adjusted vs the Illinois mean and the US mean — both population-weighted across counties — so geographies with different age structures stay apples-to-apples. Sources: CDC PLACES · 2025 release · BRFSS 2022-2023.
All 18 St. Clair County Cities With TRI Data
Pollution trends and TRI 2024 pages for every tracked city in this county. Alphabetical.
- Alorton pollution· 1 facility
- Belleville pollution· 1 facility
- Cahokia pollution· 1 facility
- Caseyville pollution· 0 facilities
- Dupo pollution· 0 facilities
- East Carondelet pollution· 0 facilities
- East St. Louis pollution· 1 facility
- Fairmont City pollution· 1 facility
- Freeburg pollution· 1 facility
- Lebanon pollution· 0 facilities
- Mascoutah pollution· 0 facilities
- New Athens pollution· 0 facilities
- O'Fallon pollution· 1 facility
- Sauget pollution· 7 facilities
- Scott AFB pollution· 1 facility
- Smithton pollution· 0 facilities
- Summerfield pollution· 0 facilities
- Swansea pollution· 0 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.