Chlorine
Unresolved Disinfectants and Disinfection Byproducts (Stage 2) violation cited in 2024 (chlorine).
City · TRI 2024
Tucson, Arizona Pollution
8 TRI facilities inside the city limits and 85 public water systems serving residents. In-city TRI releases rose meaningfully year over year (+19%). Toxic releases concentrations have more than doubled since 2010.
FIPS 0477000 · population 541,033 · Pima County
Anomaly engine
Notable Signals
Arsenic
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2025 (arsenic).
Arsenic
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2023 (arsenic).
Chlorine
Unresolved Disinfectants and Disinfection Byproducts (Stage 2) violation cited in 2025 (chlorine).
Showing the 4 most editorially weighted signals out of 79. Lower-severity signals fold into the chemical breakdown and history charts below.
Pollutant pathways
Tucson 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 are roughly unchanged from 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 are up 28% 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 are roughly unchanged from 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 43% 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) volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
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 up 15% since 2010.
Top facilities · TRI 2024
Largest Emitters Inside The City
| Facility | Top chemical | Total releases | YoY |
|---|---|---|---|
| Materion Ceramics INC.Materion CORP | Beryllium And Beryllium Compounds | 37k lb | +43% |
| U.S. Dod Usaf Davis-Monthan AfbUS Department Of Defense | LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) | 9k lb | +15% |
| Polymer Chemistry Innovations INC | MethanolHealth riskAcutely toxic if ingested or inhaled. Metabolizes to formaldehyde and formic acid, causing blindness and metabolic acidosis. (EPA) | 250 lb | 0% |
| Samuel Advanced Fabrication A Div Of Samuel Son & CO.Samuel Son & Co LTD | ManganeseHealth riskExcess inhalation can cause manganism, a Parkinson-like neurological disorder. (ATSDR) | 75 lb | -42% |
| Western Refining - Tuscon AsphaltMarathon Petroleum CORP | NaphthaleneHealth riskIARC Group 2B possible carcinogen; causes hemolytic anemia, especially in infants. (IARC) | 15 lb | — |
| Western Emulsions Tucson Emulsions PlantIdaho Asphalt Supply INC | Polycyclic aromatic compoundsHealth riskPAH class includes IARC Group 1 carcinogens (e.g., benzo[a]pyrene); long-term exposure raises cancer risk. (IARC, EPA) | 5 lb | -47% |
| Federal Correctional Complex - TucsonUS Department Of Justice | LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) | 2 lb | -100% |
| Best Block - Tucson Az PlantQuikrete Holdings | LeadHealth riskNeurotoxin. Even low childhood exposure impairs cognitive development; chronic adult exposure damages kidneys and the cardiovascular system. (EPA, ATSDR) | 0 lb | -24% |
Drinking water · SDWIS
Water Systems Serving Tucson
241 unresolved violations on the SDWIS record across utilities serving this city.
85
Utilities serving
880,617
Population served
41
Health-based · 5yr
241
Unresolved
| Water system | PWSID | Population served | Health-based · 5yr | Status |
|---|---|---|---|---|
| Federal Correctional Inst Federal | AZ0410187 | 350 | 4 | UNRESOLVED |
| Casitas De Castilian Mixed | AZ0420531 | 167 | 4 | UNRESOLVED |
| Flowing Wells Irrigation District Private | AZ0410051 | 16,000 | 3 | UNRESOLVED |
| Tierra Linda Hoa Water Company Mixed | AZ0410411 | 266 | 3 | UNRESOLVED |
| Cactus Country Rv Resort Mixed | AZ0420197 | 420 | 2 | UNRESOLVED |
| Rio Mercado Water Private | AZ0410968 | 266 | 2 | UNRESOLVED |
| Crossroads Park Mhp Mixed | AZ0420096 | 100 | 2 | UNRESOLVED |
| Coronado Forest Drive Water Coop Mixed | AZ0420475 | 30 | 2 | UNRESOLVED |
| Gator Water Company Private | AZ0410445 | 29 | 2 | UNRESOLVED |
| Adoc Tucson State-owned | AZ0420557 | 4,500 | 1 | UNRESOLVED |
| Desert Shores Rv Mhp Mixed | AZ0420033 | 220 | 1 | UNRESOLVED |
| Via Verde West Mhp Mixed | AZ0420420 | 156 | 1 | UNRESOLVED |
| Riverside Apartments Mixed | AZ0420129 | 75 | 3 | Returned to compliance |
| High Chaparral Water Coop Private | AZ0410282 | 72 | 3 | Returned to compliance |
| Thim Utility Company - Parkin Private | AZ0410250 | 69 | 3 | Returned to compliance |
| Rio Vista Mobile Home Park Mixed | AZ0420487 | 217 | 2 | Returned to compliance |
| Bella Capri Mhp Mixed | AZ0420445 | 342 | 1 | Returned to compliance |
| Desert Water Coop Mixed | AZ0410188 | 150 | 1 | Returned to compliance |
| Carolanne Drive Hoa Mixed | AZ0420529 | 72 | 1 | Returned to compliance |
| Metropolitan Dwid Private | AZ0410076 | 45,570 | 0 | UNRESOLVED |
| Avra Water Coop Inc Private | AZ0410006 | 6,685 | 0 | UNRESOLVED |
| Metropolitan Dwid - Diablo Village Private | AZ0410357 | 5,542 | 0 | UNRESOLVED |
| Ray Water Company Inc Private | AZ0410095 | 4,495 | 0 | UNRESOLVED |
| Metropolitan Dwid - Hub Private | AZ0410060 | 4,252 | 0 | UNRESOLVED |
| Spanish Trail Water Company Private | AZ0410127 | 3,822 | 0 | UNRESOLVED |
| Rincon Country East Rv Park Mixed | AZ0420602 | 912 | 0 | UNRESOLVED |
| Metropolitan Dwid - E&T System Private | AZ0410046 | 880 | 0 | UNRESOLVED |
| Mission Palms Apartments Mixed | AZ0420570 | 720 | 0 | UNRESOLVED |
| Winterhaven Water Development Private | AZ0410119 | 685 | 0 | UNRESOLVED |
| La Casita Water Company 3 Private | AZ0420606 | 605 | 0 | UNRESOLVED |
| Anway Manville Water Company Mixed | AZ0410354 | 576 | 0 | UNRESOLVED |
| Campbell Estates Mhp Private | AZ0420019 | 450 | 0 | UNRESOLVED |
| Thim Utility Company 2 Private | AZ0410228 | 445 | 0 | UNRESOLVED |
| Diamond Grove Mobile Home Estates Mixed | AZ0420542 | 385 | 0 | UNRESOLVED |
| Lazy C Water Service Private | AZ0410065 | 359 | 0 | UNRESOLVED |
| Valle Verde Del Norte Mixed | AZ0410152 | 300 | 0 | UNRESOLVED |
| Mt Lemmon Dwid Private | AZ0410140 | 290 | 0 | UNRESOLVED |
| Rio Viejo Water Municipal | AZ0410011 | 272 | 0 | UNRESOLVED |
| La Casita Water Company 2 Mixed | AZ0410410 | 261 | 0 | UNRESOLVED |
| Sierrita Mountain Water Coop Private | AZ0410208 | 258 | 0 | UNRESOLVED |
| Thim Utility Company - Well 9 Private | AZ0410206 | 254 | 0 | UNRESOLVED |
| Samalayuca Improvement Assoc Mixed | AZ0410101 | 150 | 0 | UNRESOLVED |
| Orchard Valley Mobile Home Park Mixed | AZ0420159 | 130 | 0 | UNRESOLVED |
| Mobile Home Properties Private | AZ0410319 | 114 | 0 | UNRESOLVED |
| Catalina Village Private | AZ0410219 | 107 | 0 | UNRESOLVED |
| Metropolitan Dwid - Lazy B Private | AZ0410218 | 77 | 0 | UNRESOLVED |
| Catalina Country Estates Mixed | AZ0420500 | 77 | 0 | UNRESOLVED |
| Rancho Sierrita Well Assoc Mixed | AZ0410286 | 55 | 0 | UNRESOLVED |
Showing the 48 systems with recorded health-based or unresolved violations. 37 additional systems are in compliance with no recorded health-based violations in the past 5 years and are not individually tabulated.
A public water systemis the regulated entity, not the city. EPA's SDWIS definition covers anything serving 25+ people for 60+ days a year or with 15+ service connections — that includes municipal utilities (City of Stockton), water districts, mobile home parks operating their own wells, schools, and small private subdivisions. Each system is independently monitored. Some systems serve multiple cities; some cities are served by many systems.
Equity context · ACS 2018-2022 · USEPA-clone EJ disparity
Who Lives In Tucson
Tucson, Arizona (Census place block groups): 541,033 residents. City disparity score for pm2.5 (fine particulate) sits well below the reference (12). Why we surface this →
19.6%
Low-income
57.6%
People of color
5.7%
Under age 5
15.2%
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.6below the national median
- OzoneHealth riskGround-level ozone (smog) inflames the airways. Even short exposures trigger asthma attacks and worsen chronic lung and heart disease.82in 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.77above 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.72above 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.54near 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.73above 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.57near 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.89in 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.50near 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.52near 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.68above 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.98in the highest 5% 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) | 12 | well below the reference |
| Ozone | 176 | well above the reference burden |
| Nitrogen dioxide (NO₂) | 147 | moderately above the reference |
| Diesel particulate | 135 | moderately above the reference |
| Toxic releases (RSEI) | 96 | near the reference |
| Traffic proximity | 138 | moderately above the reference |
| Lead-paint risk (pre-1960 housing) | 76 | below the reference |
| Superfund site proximity | 94 | near the reference |
| RMP-facility proximity | 87 | below the reference |
| Hazardous-waste site proximity | 98 | near the reference |
| Underground storage tanks | 108 | near the reference |
| NPDES wastewater proximity | 157 | well above the reference burden |
| Drinking-water non-compliance | 2 | 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 city'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)
11.3%
CDC PLACES · 2025 release · BRFSS 2022-2023
COPD prevalence
7.0%
CDC PLACES · 2025 release · BRFSS 2022-2023
Coronary heart disease
6.3%
CDC PLACES · 2025 release · BRFSS 2022-2023
Diabetes (diagnosed)
11.5%
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 Arizona 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.
Sources.
- EPA Toxics Release Inventory · retrieved 2026-05-07.
- EPA Safe Drinking Water Information System · retrieved 2026-05-07.