EPA Tracks Air Pollution to Your Block
Data source: ZipCheckup analysis of EPA EJScreen environmental indicators
The EPA doesn't just track what factories release. It tracks what you breathe, what's in the ground near your home, and how close you live to the facilities that produce it. The agency combines all of it into a single tool called EJScreen — and the data covers every census tract in America.
ZipCheckup has indexed EJScreen data for 42,675 ZIP codes. Here's what the EPA knows about the air you're breathing.
What EJScreen Measures
EJScreen tracks 11 environmental indicators, each representing a different dimension of environmental exposure:
Air quality:
- PM2.5 — Fine particulate matter (particles smaller than 2.5 micrometers). These penetrate deep into lungs and enter the bloodstream. The EPA tracks annual average concentrations.
- Ozone — Ground-level ozone, the main ingredient of smog. Measured as the average of the daily maximum 8-hour concentrations during the ozone season.
- Diesel particulate matter — Emissions from diesel engines. A major concern near highways, ports, and industrial areas.
Proximity to hazards:
- Superfund proximity — Distance to National Priorities List (NPL) sites, the nation's worst contaminated locations.
- RMP facility proximity — Distance to facilities that file Risk Management Plans for handling hazardous chemicals. These are the facilities most likely to cause catastrophic accidents.
- Hazardous waste proximity — Distance to Treatment, Storage, and Disposal Facilities (TSDFs) for hazardous waste.
- Wastewater discharge proximity — Distance to facilities that discharge pollutants into waterways under EPA permits.
Housing risk:
- Lead paint prevalence — Percentage of housing units built before 1960, a strong predictor of lead paint risk.
The Environmental Justice Layer
What makes EJScreen different from a simple pollution map is the demographic index. For each census tract, the EPA calculates a demographic score based on:
- Percentage of low-income residents
- Percentage of people of color
When a community has both high environmental burden AND high demographic vulnerability, the EJ Index spikes. This is the operational definition of environmental injustice — the people least able to move away from pollution are the ones most exposed to it. Water infrastructure follows the same pattern, as we show in our analysis of lead and sewer debt in Hispanic-majority ZIP codes.
The Real-World Pattern
The data tells a consistent story across American cities:
Industrial corridors and port areas show the highest diesel particulate matter. Communities near I-95 in New Jersey, the Houston Ship Channel, and the Port of Los Angeles consistently rank in the worst percentiles.
Legacy contamination clusters appear in the Superfund and hazardous waste proximity indicators. Silicon Valley — ZIP codes 94085, 94086, 94089 — has up to 15 Superfund sites within 5 kilometers, a legacy of semiconductor manufacturing. The chemical corridor along the Louisiana-Texas Gulf Coast combines TRI facility density with high diesel PM and wastewater discharge.
Lead paint risk maps directly to housing age. Cities in the Northeast and Midwest — where pre-1960 housing stock dominates — show the highest lead paint prevalence scores. Our school zone lead risk analysis explores this connection in detail.
Why ZIP-Level Data Matters
The EPA publishes EJScreen at the census tract level — areas of roughly 4,000 people. ZipCheckup aggregates this to the ZIP code level because that's how people think about where they live. You know your ZIP code. You probably don't know your census tract number.
This aggregation reveals neighborhood-level patterns that matter for practical decisions:
- Home buying: Two ZIP codes in the same city can have dramatically different environmental profiles. A 10-minute drive can mean the difference between the 30th and 90th percentile for diesel particulate exposure.
- Health concerns: Long-term exposure to elevated PM2.5 and ozone is linked to cardiovascular disease, respiratory illness, and reduced life expectancy. EJScreen data quantifies these exposures.
- Property values: Environmental justice indicators correlate with property value trajectories. Communities facing cleanup liability or regulatory action may see long-term valuation impacts.
The Connection to Water
Air pollution and water quality are not separate problems. Particulate matter deposits into watersheds. Industrial facilities that emit air pollutants often discharge into water systems too. And the same communities that face the worst air quality tend to have the most water system violations and the oldest infrastructure.
Environmental justice extends into utility communication itself: 1,454 US public water utilities (22.9% of the 5,572 tracked in the CCR Rich Dataset) serve communities where Spanish-language CCR disclosure is required by federal rule — together reaching 67.8 million people across California, Missouri, Montana, Illinois, and Texas.
ZipCheckup combines EJScreen data with EPA water quality violations, TRI facility data, lead risk assessments, and infrastructure ratings to give you a complete environmental picture — not just one slice of it.
How to Check Your ZIP Code
Every ZIP code in our database includes EJScreen-derived environmental data as part of its safety report. You can see:
- Pollution proximity indicators for your area
- Lead paint risk based on housing age
- Superfund and hazardous waste facility proximity
- Your ZIP's overall environmental risk level
- How your area compares to national percentiles
The EPA has already mapped the pollution. The question is whether you've checked what they found where you live.
Methodology: ZipCheckup indexes EPA EJScreen environmental indicators for 42,675 ZIP codes. EJScreen data includes 11 environmental indicators and demographic indices at the census tract level, aggregated to ZIP codes. Environmental justice indices combine environmental burden with demographic vulnerability (low-income and minority population percentages). All data reflects the most recent EJScreen release.
Frequently Asked Questions
What is EJScreen?
EJScreen is the EPA's Environmental Justice Screening and Mapping Tool. It combines environmental indicators (like air pollution levels, proximity to hazardous facilities, and lead paint prevalence) with demographic information to identify communities that face disproportionate environmental burdens.
What environmental indicators does EJScreen track?
EJScreen tracks 11 environmental indicators including particulate matter (PM2.5), ozone levels, diesel particulate matter, lead paint prevalence, proximity to Superfund sites, proximity to hazardous waste facilities, proximity to Risk Management Plan (RMP) facilities, and wastewater discharge proximity. Each indicator is paired with demographic data to produce an environmental justice index.
What is an EJ Index?
An EJ Index combines an environmental indicator with a demographic index. The demographic index accounts for the percentage of low-income residents and people of color in a census tract. A high EJ Index means a community faces both high environmental burden AND high social vulnerability — the definition of environmental injustice.
Can I check EJScreen data for my ZIP code?
Yes. Enter your ZIP code on ZipCheckup to see your full environmental profile, including EJScreen indicators, pollution proximity data, and environmental justice risk levels.