Guide · Toxics Release Inventory
Understanding the Toxics Release Inventory
According to the EPA's Toxics Release Inventory (the 2023 EPA TRI reporting year), what the data tells you about industrial pollution in your community and how to use it.
- 770+
- toxic chemicals tracked
- 1986
- created by EPCRA after Bhopal
- 4
- release pathways (air · water · land · off-site)
- 25,000+
- facilities in this portal corpus
TRI transparency verdict
TRI is a self-reported inventory of Zinc compounds leads at 2980M lbs in the latest EPA extract, transparency under EPCRA, not a violation score or health ranking.
- 770+
- listed chemicals
- 4
- release pathways
- 2980M
- top chemical (million lbs)
- 2023
- TRI reporting vintage
High pounds do not prove illegality; compare pathway, toxicity flags, and trends on each facility page.
The chemicals released in the largest volumes
Top reported TRI chemicals nationwide, a concrete example of what the data shows
- Zinc compounds
- Nitrate compounds (w…
- Lead And Lead Compo…
- Lead compounds
- Arsenic compounds 1,167
- Ammonia 874
- Methanol 653
- Manganese And Manga… 637
- Barium compounds (ex… 586
- Manganese compounds 436
What this shows Volume tops the chart for industrial solvents and metal compounds, but a smaller release of a highly toxic or persistent chemical can matter more for health than a large release of a common one, read the carcinogen and PBT flags alongside the pounds.
What TRI Tracks
The Toxics Release Inventory was created after the 1984 Bhopal disaster in India, which killed thousands and exposed the lack of public information about industrial chemicals. Congress passed the Emergency Planning and Community Right-to-Know Act (EPCRA) in 1986, requiring facilities to publicly report their toxic chemical releases.
Today, facilities that manufacture, process, or otherwise use more than threshold quantities of any of the 770+ listed chemicals must file annual TRI reports. The data covers four release pathways:
- Air emissions: Both from smokestacks (point sources) and diffuse sources (fugitive emissions like evaporation from storage tanks).
- Water discharges: Direct releases to rivers, streams, and other surface water bodies.
- Land disposal: On-site landfills, surface impoundments, and underground injection wells.
- Off-site transfers: Waste shipped to other facilities for treatment, recycling, energy recovery, or disposal.
PlainEnviro tracks all TRI-reporting facilities. Browse by state or search for specific facilities to see their release data.
How to Read TRI Data
Each facility's TRI report lists the chemicals released, quantities in pounds, and the release pathway. When evaluating this data, keep these principles in mind:
- Pounds released ≠ health risk. A million pounds of a relatively benign chemical may pose less risk than a few hundred pounds of a highly toxic one. Chemical toxicity, exposure pathways, and population proximity all matter.
- Trends matter more than snapshots. A single year's data can be misleading. Look at 5-year trends to see if a facility is increasing or decreasing releases. PlainEnviro shows trends for every facility.
- Reporting ≠ violating. TRI is a right-to-know law. Facilities report what they release legally under their permits. High numbers may be concerning, but they aren't automatically violations.
- Context is essential. Compare a facility's releases to others in the same industry. A chemical plant releasing 50,000 pounds may be performing well relative to peers, or poorly, the raw number alone doesn't tell you.
Key Chemicals to Watch
While the TRI covers 770+ chemicals, a handful drive most of the public health concern:
- Lead and lead compounds: Neurotoxin with no safe exposure level, especially dangerous for children.
- Mercury and mercury compounds: Accumulates in the food chain, particularly fish. Damages the nervous system.
- Benzene: Known carcinogen linked to leukemia. Released by petrochemical facilities and refineries.
- Formaldehyde: Classified as a known carcinogen. Widely used in manufacturing.
- Hydrochloric acid: Released in large volumes by coal-fired power plants. Irritates respiratory system.
Browse PlainEnviro's chemical directory to see which chemicals are released most in your state and which facilities report them.
Using TRI for Community Research
TRI data is most valuable when combined with other information. If you're researching environmental conditions in your area:
- Start with your county page to see all reporting facilities and total releases.
- Check individual facility pages for chemical breakdowns and 5-year trends.
- Cross-reference with environmental screening data for cumulative risk indicators.
- Check Superfund sites nearby for historical contamination.
- Review your community's drinking water quality data.
Using TRI in your area
Start with totals, then drill into pathway and 5-year trends before inferring risk.
- Open your county or state page for all reporting facilities and combined releases. Browse by state
- On each facility page, split air vs land vs water, rankings by total pounds hide pathway. Facility lookup
- Pair TRI with SDWIS and Superfund context; each program answers a different question. EPA programs guide
TRI does not model dispersion or dose; it is a community right-to-know ledger, not an exposure calculator.
This content is for informational purposes only. Always follow official guidance from local authorities. For specific health concerns about chemical exposure, consult your state environmental agency or a toxicologist.