12 KiB
DS-00008 — EPA Air Quality System (AQS)
Environmental Health & Quality of Life Indicators
Overview
The EPA Air Quality System (AQS) is the authoritative source for ambient air quality measurements in the United States. This data source provides regulatory-grade air quality data from 4,000+ monitoring stations nationwide, with a focus on parameters most critical to human health and wellbeing.
Key Insight: Air quality is a structural determinant of wellbeing. You cannot "self-care" your way out of breathing toxic air. PM2.5 exposure reduces life expectancy by months to years in polluted areas. Environmental injustice: low-income communities and communities of color are disproportionately exposed.
Why This Matters for Substrate
Human Progress & Wellbeing Focus
Air quality is a fundamental structural constraint on human flourishing:
- Life Expectancy: PM2.5 reduces longevity by 1.8 years globally (Air Quality Life Index)
- Involuntary Exposure: You breathe ~20,000 times per day — exposure is unavoidable
- Environmental Injustice: ZIP code determines exposure — structural inequality
- Health Impacts: Cardiovascular disease, respiratory disease, cognitive decline, pregnancy outcomes
- Quality of Life: Restricted outdoor activity on high pollution days, healthcare costs, lost productivity
Unlike individual health behaviors (diet, exercise), air quality is a collective problem requiring structural solutions.
Data Source Details
Authority
- Organization: U.S. Environmental Protection Agency (EPA)
- Office: Office of Air Quality Planning and Standards (OAQPS)
- Legal Mandate: Clean Air Act (1970, amended 1990)
- Data Quality: Federal Reference/Equivalent Methods (FRM/FEM) — regulatory-grade
- Established: 1971 (50+ years of air quality monitoring)
Coverage
- Geographic: United States (50 states, DC, territories)
- Temporal: 1980-present (45+ years of validated data)
- Granularity: Monitoring site level (latitude/longitude)
- Network Size: 4,000+ active monitoring stations
- Update Frequency: Continuous monitoring; 6-month validation lag for finalized data
Key Parameters (Health Priority)
| Code | Parameter | Health Impact | Priority |
|---|---|---|---|
| 88101 | PM2.5 | Mortality, cardiovascular disease, respiratory disease, cognitive decline, reduced life expectancy | CRITICAL |
| 44201 | Ozone (O3) | Respiratory irritant, asthma exacerbation, lung damage | HIGH |
| 42401 | SO2 | Respiratory irritant | Medium |
| 42101 | CO | Cardiovascular stress | Medium |
| 42602 | NO2 | Respiratory irritant, ozone precursor | Medium |
| 81102 | PM10 | Respiratory health | Medium |
Repository Structure
DS-00008—EPA_Air_Quality_System/
├── README.md # This file (overview and usage guide)
├── source.md # Comprehensive cataloging (authority, methodology, limitations)
├── update.ts # TypeScript data fetcher with rate limiting
├── .env.example # Environment variable template (API credentials)
├── .gitignore # Git ignore patterns (protects API keys, data files)
└── data/ # Air quality data (JSON files)
└── README.md # Data structure documentation
Quick Start
Prerequisites
- Bun (JavaScript runtime): https://bun.sh/
- EPA AQS API Key (free, immediate approval)
1. Register for API Access
Option A: Email Registration
# Email aqs.support@epa.gov
Subject: AQS API Access Request
Body: Please provide API key for email: your_email@example.com
Option B: Automated Signup
curl "https://aqs.epa.gov/data/api/signup?email=your_email@example.com"
You will receive your API key via email (typically within minutes).
2. Configure Environment Variables
# Copy example environment file
cp .env.example .env
# Edit .env with your credentials
# Replace your_email@example.com and your_api_key_here
nano .env
3. Fetch Air Quality Data
Default: Fetch PM2.5 and Ozone for California (last year)
bun update.ts
Custom: Specify year, states, parameters
# Multiple states, specific year
bun update.ts --year 2023 --states CA,NY,TX
# Focus on PM2.5 only (most health-critical)
bun update.ts --year 2023 --states CA --parameters PM25
# Full criteria pollutants
bun update.ts --year 2023 --states CA,NY,TX,FL --parameters PM25,OZONE,SO2,CO,NO2,PM10
Get help
bun update.ts --help
4. View Results
Data files are saved in data/ directory:
ls -lh data/
# aqs_2023_CA_2025-10-27.json
# aqs_2023_CA_stats_2025-10-27.json
API Rate Limits (CRITICAL)
EPA enforces strict rate limits:
- ⚠️ 10 requests per minute (HARD LIMIT)
- ⚠️ Account suspension if violated
The update.ts script automatically enforces 6-second delays between requests.
Do NOT bypass rate limiting. EPA will suspend your account.
Data Validation Lag
- Real-time to preliminary: <1 hour (via AirNow API)
- Preliminary to validated: 6-12 months (quality assurance)
- AQS finalized data: 6-12 months after collection
For real-time air quality, use AirNow API instead: https://www.airnow.gov/
Environmental Health Context
Why Air Quality is a Structural Wellbeing Determinant
-
Involuntary Exposure
- You breathe ~20,000 times per day
- Cannot avoid ambient air pollution without relocating
- Relocation requires economic resources (not "personal choice")
-
Life Expectancy Impact
- PM2.5 reduces longevity by months to years in polluted areas
- Equivalent to smoking in highly polluted regions
- Measurable, quantifiable health burden
-
Environmental Injustice
- Low-income communities disproportionately exposed (NEJM 2021)
- Communities of color exposed to higher pollution even controlling for income
- Proximity to highways, industrial facilities, ports (structural inequality)
- Monitoring gap: Low-income communities historically undermonitored (data invisibility → policy neglect)
-
Health Equity
- Cardiovascular disease: PM2.5 linked to stroke, heart attack, atherosclerosis
- Respiratory disease: Asthma, COPD, lung cancer (IARC Group 1 carcinogen)
- Cognitive decline: Dementia, Alzheimer's, childhood cognitive impairment
- Pregnancy outcomes: Low birth weight, preterm birth
-
Quality of Life
- Outdoor activity restrictions on high pollution days
- Healthcare costs (emergency visits, hospitalizations)
- Lost work/school days (respiratory illness)
- Mental health impacts (environmental degradation stress)
You cannot "self-care" your way out of this. It requires collective action, policy change, and structural intervention.
Use Cases
1. Environmental Justice Research
Research Question: Which communities are disproportionately exposed to PM2.5?
# Fetch PM2.5 data for multiple states
bun update.ts --year 2023 --states CA,NY,TX,IL --parameters PM25
# Cross-reference with Census demographic data (DS-00006)
# Identify exposure disparities by race, income, ZIP code
2. Life Expectancy Modeling
Research Question: How does PM2.5 exposure impact life expectancy across U.S. counties?
# Fetch multi-year PM2.5 data
bun update.ts --year 2023 --states ALL --parameters PM25
# Link to CDC mortality data (DS-00005)
# Calculate life expectancy impact using AQLI conversion factors
# (1 µg/m³ PM2.5 increase = ~0.1 year life expectancy loss)
3. Policy Evaluation
Research Question: Did Clean Air Act regulations reduce ozone levels?
# Fetch historical data (multiple years)
bun update.ts --year 2020 --states CA --parameters OZONE
bun update.ts --year 2015 --states CA --parameters OZONE
bun update.ts --year 2010 --states CA --parameters OZONE
# Analyze trends over time
# Evaluate regulatory effectiveness
4. Health Impact Assessment
Research Question: What are the health costs of air pollution in California?
# Fetch PM2.5 and Ozone
bun update.ts --year 2023 --states CA --parameters PM25,OZONE
# Link to health outcomes data (hospitalizations, mortality)
# Calculate attributable burden using EPA BenMAP tools
Known Limitations
Coverage Gaps
- Urban bias: 85% of monitors in metropolitan areas; rural areas undermonitored
- Environmental justice monitoring gap: Low-income communities historically excluded
- Tribal lands: Limited tribal monitoring (improving)
- Territories: Limited coverage in Puerto Rico, U.S. Virgin Islands
Methodological Limitations
- Point measurements: Monitors represent ~1-10 km radius (not every location monitored)
- 24-hour averages for PM: Daily averages mask hour-to-hour variability
- Spatial scale mismatch: Within-neighborhood gradients missed
- Indoor air quality: Not measured (people spend 90% of time indoors)
Temporal Limitations
- 6-12 month validation lag: Not suitable for real-time analysis (use AirNow API)
- Historical data: Digital records begin 1980 (pre-1980 limited)
Inappropriate Uses
- ❌ DO NOT use for real-time alerts → Use AirNow API
- ❌ DO NOT use for individual exposure → Use personal monitors, exposure modeling
- ❌ DO NOT assume unmonitored = clean → Absence of data ≠ absence of pollution
- ❌ DO NOT ignore monitoring gaps → Undermonitoring = data invisibility
Related Data Sources
| Source | Relationship | Use Case |
|---|---|---|
| DS-00005 — CDC WONDER Mortality | Health outcomes | Air pollution-attributable deaths |
| DS-00006 — Census ACS Social Wellbeing | Demographics | Environmental justice analysis |
| DS-00001 — WHO Global Health Observatory | Global context | International air quality comparisons |
| DS-00003 — World Bank Open Data | Economic indicators | Air quality and economic development |
External Resources
Official Documentation
- EPA AQS Homepage: https://aqs.epa.gov/
- API Documentation: https://aqs.epa.gov/aqsweb/documents/data_api.html
- 40 CFR Part 58 (Monitoring Requirements): https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-58
Research & Analysis Tools
- Air Quality Life Index (AQLI): https://aqli.epic.uchicago.edu/
- EPA BenMAP (Health Impact Assessment): https://www.epa.gov/benmap
- AirNow (Real-time Data): https://www.airnow.gov/
Key Research
- Harvard Six Cities Study: Seminal air pollution epidemiology (PM2.5 and mortality)
- American Cancer Society CPS-II: Air pollution and life expectancy
- Environmental Justice Literature: Exposure disparities by race, income (NEJM 2021)
Citation
APA 7th:
U.S. Environmental Protection Agency. (2025). Air Quality System (AQS).
https://aqs.epa.gov/aqsweb/
Data Citation (Specific):
U.S. Environmental Protection Agency. (2024). "PM2.5 Daily Average Concentrations,
2020-2023" [Parameter Code: 88101]. Air Quality System.
https://aqs.epa.gov/aqsweb/. Accessed October 27, 2025.
Contributing
Report Issues
- Data quality concerns: aqs.support@epa.gov
- Script bugs/improvements: Create issue in Substrate repository
Extend Functionality
Contributions welcome:
- Additional data processing utilities
- Integration with Census demographic data
- Environmental justice analysis tools
- Visualization dashboards
License
Data: Public Domain (U.S. Government Work) — CC0 1.0 Universal
Code: (Inherit from Substrate project license)
Contact
Data Source Cataloger: DM-001 Created: 2025-10-27 Last Updated: 2025-10-27 Status: Reviewed
Remember: Air quality is not an individual choice — it's a structural determinant of wellbeing. This data enables us to measure environmental injustice, evaluate policy effectiveness, and advocate for cleaner air as a human right.