Total TRI releases
Total TRI releases at St. Clair County have more than three-quarters since 2010 (through 2024).
County · TRI 2024
St. Clair County, Michigan Pollution
10 top TRI facilities tracked here. PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) fell meaningfully year over year (-29%). PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have more than halved since 2010.
FIPS 26147 · population 160,257
Anomaly engine
Notable Signals
Top facilities mapped
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.
Pollutant pathways
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 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 15% since 2010.
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 halved 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 have fallen 30% since 2010.
Top facilities · 2024
Where The Chemical Releases Are Concentrated
| Facility | City | Top chemical | Total releases | YoY |
|---|---|---|---|---|
| Dte Electric Co-Belle River Power PlantDte Energy Co | China Township | Barium And Barium CompoundsHealth riskSoluble barium compounds are toxic if ingested, affecting the heart, kidneys, and nervous system. Insoluble forms (e.g. barium sulfate) are far less toxic. (EPA) | 756k lb | -49% |
| Intertape Polymer GroupIntertape Polymer Group | Marysville | TolueneHealth riskCentral-nervous-system depressant. Chronic high exposure causes hearing loss and developmental effects. (EPA, ATSDR) | 663k lb | -9% |
| Magna Electric Vehicle StructuresMagna US Holding INC | Saint Clair | Certain glycol ethersHealth riskReproductive toxicants; some cause testicular damage and developmental harm. (EPA) | 55k lb | +349% |
| Mueller Brass COMueller Industries INC | Port Huron | Zinc compoundsHealth riskGenerally low acute toxicity. Chronic high-dose exposure disrupts copper absorption and immune function. (ATSDR) | 17k lb | -12% |
| Marysville Ethanol LLC | Marysville | AcetaldehydeHealth riskIARC Group 2B possible carcinogen (Group 1 in connection with alcohol consumption); eye and respiratory irritant. (IARC) | 16k lb | +4% |
| Kksp Precision MachiningKksp Precision Machining LLC | East China | DichloromethaneHealth riskIARC Group 2A probable carcinogen; central-nervous-system depressant; banned for most consumer paint-stripper uses. (IARC, EPA) | 15k lb | +19% |
| Sunsation Products INC | Clay Township | StyreneHealth riskIARC Group 2A probable carcinogen; central-nervous-system effects from inhalation. (IARC, EPA) | 11k lb | +28% |
| Iac Port Huron LLCInternational Automotive Components Group North America INC | Port Huron | DiisocyanatesHealth riskLeading cause of occupational asthma; severe respiratory sensitizers. (OSHA) | 11k lb | +2028808% |
| Michigan Metal CoatingsMmc Systems | Port Huron | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 7k lb | -36% |
| Zf Axle Drives MarysvilleZf North America INC | Marysville | ManganeseHealth riskExcess inhalation can cause manganism, a Parkinson-like neurological disorder. (ATSDR) | 4k lb | -8% |
Equity context · ACS 2018-2022 · USEPA-clone EJ disparity
Who Lives In St. Clair County
All block groups in St. Clair County County, MI: 160,257 residents. County disparity score for pm2.5 (fine particulate) sits well below the reference (23). Why we surface this →
11.9%
Low-income
9.7%
People of color
5.2%
Under age 5
19.4%
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.26below the national median
- OzoneHealth riskGround-level ozone (smog) inflames the airways. Even short exposures trigger asthma attacks and worsen chronic lung and heart disease.80in the highest 20% nationally
- 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.56near 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.22below 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.63above 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.23below 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.69above 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.56near the national median
- 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.31below 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.43near 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.80in the highest 20% nationally
- 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.22below the national median
- 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) | 23 | well below the reference |
| Ozone | 49 | well below the reference |
| Nitrogen dioxide (NO₂) | 51 | below the reference |
| Diesel particulate | 22 | well below the reference |
| Toxic releases (RSEI) | 41 | well below the reference |
| Traffic proximity | 21 | well below the reference |
| Lead-paint risk (pre-1960 housing) | 52 | below the reference |
| Superfund site proximity | 0 | well below the reference |
| RMP-facility proximity | 16 | well below the reference |
| Hazardous-waste site proximity | 31 | well below the reference |
| Underground storage tanks | 46 | well below the reference |
| NPDES wastewater proximity | 16 | well below the reference |
| Drinking-water non-compliance | 4 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Health context
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)
11.7%
CDC PLACES · 2025 release · BRFSS 2022-2023
COPD prevalence
9.2%
CDC PLACES · 2025 release · BRFSS 2022-2023
Coronary heart disease
7.7%
CDC PLACES · 2025 release · BRFSS 2022-2023
Diabetes (diagnosed)
12.2%
CDC PLACES · 2025 release · BRFSS 2022-2023
Frequent mental distress
18.3%
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 Michigan 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.
Browse
All 9 St. Clair County Cities With TRI Data
Pollution trends and TRI 2024 pages for every tracked city in this county. Alphabetical.
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.