Guide · Toxics Release Inventory
Understanding the Toxics Release Inventory
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)
- 25,902
- U.S. facilities reporting
Key Takeaway
The TRI is a transparency tool, not a violation tracker. It shows which chemicals industrial facilities release, in what quantities, and through what pathways (air, water, land). More than 25,000 facilities report annually. The data is powerful for understanding cumulative community exposure, but release volumes alone don't tell you about actual health risk.
The chemicals released in the largest volumes
Top reported TRI chemicals nationwide, a concrete example of what the data shows
- Zinc compounds
Zinc compounds
2,967 million lbs
- Lead And Lead Compo…
Lead And Lead Compounds
1,385 million lbs
- Nitrate compounds (w…
Nitrate compounds (water dissociable; reportable only when in aqueous solution)
1,369 million lbs
- Lead compounds
Lead compounds
1,326 million lbs
- Arsenic compounds 1,167
Arsenic compounds
1,167 million lbs
- Ammonia 867
Ammonia
867 million lbs
- Methanol 645
Methanol
645 million lbs
- Manganese And Manga… 632
Manganese And Manganese Compounds
632 million lbs
- Barium compounds (ex… 585
Barium compounds (except for barium sulfate (CAS No. 7727-43-7))
585 million lbs
- Manganese compounds 433
Manganese compounds
433 million lbs
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.
Frequently Asked Questions
What is the Toxics Release Inventory?
The TRI is a public database maintained by the EPA that tracks the release and management of over 770 toxic chemicals by industrial facilities. Facilities that manufacture, process, or use these chemicals above certain thresholds must report annually. The program was created by the Emergency Planning and Community Right-to-Know Act (EPCRA) in 1986.
Does a TRI release mean the facility is breaking the law?
No. TRI reporting is a transparency requirement, not a violation indicator. Facilities can legally release certain amounts of chemicals under their permits. The TRI data tells you what is being released, not whether it exceeds legal limits. However, high release volumes relative to community size may warrant further investigation.
What types of releases are tracked?
TRI tracks four types of releases: air emissions (stack and fugitive), water discharges (to surface water), land disposal (landfills, underground injection), and off-site transfers (waste sent to other facilities for treatment or disposal). Air emissions are typically the largest category for most facilities.
How do I know if a TRI facility is near my home?
Search PlainEnviro by state, county, or facility name to find TRI-reporting facilities in your area. Each facility page shows the chemicals released, quantities, and 5-year trends. You can also browse by county to see all reporting facilities in your area and their combined releases.
Are TRI numbers in pounds the same as pollution I breathe?
Not directly. TRI reports total pounds released, but actual exposure depends on many factors: how the chemical disperses, weather patterns, distance from the facility, the chemical's properties (some break down quickly, others persist), and whether releases are to air, water, or land. TRI data is best used for community-level comparisons and trend analysis, not individual exposure assessment.
Which industries release the most toxic chemicals?
Metal mining, electric utilities, chemical manufacturing, and primary metals (steel, aluminum) consistently top the TRI rankings by total release volume. However, volume alone doesn't determine risk, a small release of a highly toxic chemical can be more concerning than a large release of a less harmful one.
Sources
- U.S. Environmental Protection Agency, Toxics Release Inventory (TRI), 2023 data
- EPA Envirofacts, TRI Basic Data Download
- EPCRA Section 313, Reporting requirements and chemical list
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.
