Top Industries by TRI Releases: What the 2023 Data Shows
Not all industries are equal when it comes to toxic chemical releases. The Toxic Release Inventory consistently shows that a handful of industry sectors account for the large majority of reported TRI releases nationally. Understanding which sectors dominate — and which chemicals they release — is essential context for interpreting facility-level data and for understanding the landscape of industrial pollution in the United States.
Metal Mining: The Consistent Leader
Metal mining has consistently led all TRI sectors in total reported releases, primarily because of the enormous quantities of waste rock and tailings that must be managed at mine sites. The TRI quantities for metal mining dwarf manufacturing sectors, though it\'s important to note that much of the "release" in mining TRI data represents land disposal of waste rock that contains metals — a different environmental risk profile than air emissions from chemical plants. Copper, gold, silver, lead, and zinc mining operations account for much of this category.
Chemicals and Electric Utilities
After mining, the chemicals manufacturing sector and electric power generation are typically the next largest TRI sectors. Chemical manufacturers release a wide range of compounds; electric utilities release primarily nitric acid and sulfuric acid associated with combustion, as well as heavy metals like mercury and arsenic in coal combustion waste. The transition from coal to natural gas in power generation has significantly reduced TRI releases from the utility sector over the past 15 years.
Hazardous Waste Management
Hazardous waste treatment and disposal facilities appear prominently in TRI data because they receive waste from other sectors — the chemicals they handle and release were originally generated elsewhere. This creates some double-counting in sector-level TRI totals: the same chemical may be counted once when generated by a manufacturer and again when managed by a waste treatment facility.
How to Explore by Industry
EmissionsLookup allows you to browse facilities by industry sector at the industry index. Each sector page shows the facilities with the highest TRI releases, along with compliance summary statistics. For specific chemicals of concern — whether for a community near a facility or for policy research — browse by chemical at the chemical index. For context on who lives near high-releasing facilities, CensusDepth provides census tract demographic data.