EPA TRI Chemical

Mercury and Mercury Compounds

EPA TRI Category Code: N458

Total releases
16.9M lbs
Number of facilities
972
Carcinogen
No
PBT substance
Yes
Verify at EPA TRI →
PBT

According to the EPA Toxics Release Inventory, Mercury and Mercury Compounds (EPA TRI Category Code N458) is disclosed by 972 Form R facilities totaling 16.9M lbs of reported releases. It is also listed as a persistent bioaccumulative toxicant (PBT) in the TRI extract. TRI pounds are self-reported disclosure totals, not a measured public-health risk score.

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Mercury and Mercury Compounds (EPA TRI Category Code N458) is a chemical tracked by the EPA Toxics Release Inventory (TRI) program under Section 313 of the Emergency Planning and Community Right-to-Know Act. The TRI requires industrial facilities above specified threshold quantities to disclose annual manufacturing, processing, and otherwise-used volumes, along with quantities released to air, water, land, and off-site transfers.

A carcinogen flag, when present on other chemicals in this database, reflects an assessment from EPA, IARC, or the National Toxicology Program rather than a TRI-specific determination. The PBT (persistent, bioaccumulative, toxic) status above carries a lower TRI reporting threshold than most listed chemicals, reflecting elevated regulatory concern about long-term environmental buildup. The largest individual disclosure in the current dataset comes from NEVADA GOLD MINES LLC - GOLDSTRIKE MINES INC in NV at 5.2M lbs.

TRI volumes are self-reported estimates, not measured stack emissions, and each pound counts equally regardless of chemical toxicity, so total pounds should not be equated with total risk. Inclusion of a chemical or facility in the TRI does not itself establish a health hazard; it documents the public right-to-know record. Consult EPA's IRIS (Integrated Risk Information System) and the Agency for Toxic Substances and Disease Registry for health-effect summaries.

LAND pathway mix

Mercury and Mercury Compounds: how the 16.9M lbs splits

16.9M lbs across all reported pathways

  • Land Disposal14.9M lbs88.5%
  • Off-site Transfers1.9M lbs11.0%
  • Air Releases80.9K lbs0.5%
  • Water Discharges4.8K lbs<0.1%

Mercury and Mercury Compounds's 16.9M lbs Form-R total is LAND, with land disposal making up 88.5% of the bar. Next segment: off-site transfers at 11.0%.

Trend & Where It's Reported

Reported Release Trend

Between 2019 and 2023, cumulative annual Mercury and Mercury Compounds releases across all reporting facilities decreased by 41% (4.3M lbs → 2.5M lbs). Year-to-year swings reflect facility openings/closures and reporting changes as much as underlying activity.

Geographic Concentration

Reporting for Mercury and Mercury Compounds is highly concentrated: Nevada accounts for 81.2% of the reported total (23 facilities). Next: Arkansas.

  • Nevada 13.7M lbs
  • Arkansas 872.9K lbs
  • Alaska 625.3K lbs
  • Alabama 536.3K lbs
  • Utah 285.8K lbs
Industry Sources

Reporting for Mercury and Mercury Compounds is highly concentrated by industry: Metal Mining facilities account for 85.8% of the reported total (42 facilities). Next: Hazardous Waste.

  • Metal Mining 14.5M lbs
  • Hazardous Waste 2.1M lbs
  • Electric Utilities 105.4K lbs
  • Chemicals 64.7K lbs
  • Other 37.1K lbs

Which facilities release the most of this chemical?

Facilities with the largest reported releases of Mercury and Mercury Compounds. Up to 50 shown.

# Facility Release (lbs)
1 Nevada Gold Mines LLC - Goldstrike Mines Inc
5.2M lbs
2 Nevada Gold Mines LLC - Carlin South Area
3.4M lbs
3 Nevada Gold Mines LLC - Turquoise Ridge
2.4M lbs
4 Nevada Gold Mines Llc-Cortez District
1.9M lbs
5 Clean Harbors el Dorado LLC
868.7K lbs
6 Red Dog Operations
624.8K lbs
7 Chemical Waste Management
530.1K lbs
8 Clean Harbors Aragonite LLC
204.4K lbs
9 Marigold Mining Co
201.3K lbs
10 Clean Harbors Deer Park LLC
175.0K lbs
11 Nevada Gold Mines LLC - Phoenix Mine
151.1K lbs
12 Fiore Gold Pan Mine
142.2K lbs
13 Clean Harbors Environmental Services Inc
125.0K lbs
14 Jerritt Canyon Mine
105.5K lbs
15 Coeur Rochester Inc
73.3K lbs
16 Kennecott Utah Copper Mine Concentrators & Power Plant
62.2K lbs
17 US Ecology Idaho Inc.
50.7K lbs
18 Clean Harbors Reidsville LLC
46.4K lbs
19 Eq Detroit Inc
34.1K lbs
20 Freeport-McMoran Bagdad Inc
24.1K lbs
21 Mesquite Mine
23.1K lbs
22 Wayne Disposal Inc
20.4K lbs
23 Universal Products Inc.
19.4K lbs
24 Isabella Pearl Mine (006-240-02)
18.0K lbs
25 Mosaic Fertilizer Llc-New Wales Plant
16.3K lbs
26 Wharf Resources
13.6K lbs
27 Lighting Resources LLC
10.5K lbs
28 Mosaic Fertilizer Llc-Bartow
9.0K lbs
29 Hycroft Mine
8.8K lbs
30 St Lawrence Zinc Co Balmat 4 Mine & Mill
8.2K lbs
31 US Ecology Texas Inc
8.1K lbs
32 Mosaic Fertilizer Llc-Riverview
8.0K lbs
33 Rawhide Mine
7.9K lbs
34 Raytheon Vision Systems
7.6K lbs
35 Prairie State Generating Co
7.3K lbs
36 Cripple Creek & Victor Gold Mining Co
7.0K lbs
37 Clean Harbors San Jose LLC
7.0K lbs
38 Energysolutions LLC
6.3K lbs
39 Westlake Natrium LLC
6.2K lbs
40 P4 Production LLC
5.6K lbs
41 Kennecott Utah Copper Smelter & Refinery
5.2K lbs
42 Eaglepicher Technologies LLC
5.1K lbs
43 Gavin Power LLC
4.7K lbs
44 Hecla Ltd Lucky Friday Mine Unit
4.5K lbs
45 Asarco LLC Mission Complex
4.3K lbs
46 Chaparral Steel Midlothian LP
4.1K lbs
47 Colstrip Steam Electric Station
4.0K lbs
48 Eastman Chemical Co Tennessee Operations
3.8K lbs
49 Raytheon Vision Systems
3.8K lbs
50 Basin Electric Antelope Valley Station
3.5K lbs

Frequently Asked Questions

What is Mercury and Mercury Compounds in the EPA TRI?
Mercury and Mercury Compounds (EPA TRI Category Code: N458) is a chemical tracked by the EPA Toxic Release Inventory (TRI) program. It is not marked as a carcinogen in the TRI classification set. It is classified as a persistent bioaccumulative toxicant (PBT) in the TRI extract. 972 facilities in the United States report releasing this chemical to the EPA.
How much Mercury and Mercury Compounds is disclosed in U.S. TRI filings?
U.S. facilities have reported a total of 16.9M lbs of Mercury and Mercury Compounds releases to the EPA Toxic Release Inventory across 972 facilities. Release quantities are self-reported estimates covering air, water, land, and off-site transfers. They are disclosure totals, not toxicity-weighted harm scores.
How does EPA TRI classify Mercury and Mercury Compounds?
Mercury and Mercury Compounds is not marked as a carcinogen in the TRI classification set. It is also listed as a persistent bioaccumulative toxicant (PBT), which uses lower TRI reporting thresholds. TRI classification flags document inventory listing status; they are not a site-specific exposure or health diagnosis. For health-effect summaries see EPA IRIS and ATSDR toxicological profiles.
Which facilities disclose the most Mercury and Mercury Compounds?
Nevada Gold Mines LLC - Goldstrike Mines Inc in NV reports the largest disclosed release of Mercury and Mercury Compounds in this dataset, at 5.2M lbs. Most reporting facilities for this chemical fall under metal mining. Release data is self-reported annually to the EPA under the TRI program. View the full list of 972 facilities on this page.
Why is Mercury and Mercury Compounds listed under code N458 instead of a CAS number?
N458 is an EPA TRI Category Code, not a CAS Registry Number. EPA assigns category codes (N-prefix and K-prefix) to chemical groups that share reporting requirements, for example, "Mercury and Mercury Compounds" covers many distinct compounds aggregated for TRI reporting. Individual constituents may have their own CAS Registry Numbers (e.g., elemental Lead is CAS 7439-92-1), but the group is reported under the single TRI Category Code.

Health Information

Persistent Bioaccumulative Toxicant (PBT): This chemical is classified as a PBT by the EPA. PBT chemicals are toxic, persist in the environment, and bioaccumulate in food chains. Because of these properties, even relatively small releases can pose a significant threat to human health and the environment over time.

Data comes from the EPA Toxic Release Inventory (TRI) program. Release quantities are self-reported by facilities and may represent estimates. The total shown aggregates reports across all facilities and reporting years.

PlainEnviro presents this data without advocacy framing. The presence of a chemical in the TRI database does not by itself indicate a health risk at current exposure levels. For health-related questions about specific chemical exposures, consult your local health agency or a toxicologist.

Related

Data sourced from the U.S. Environmental Protection Agency (EPA). See our methodology for details. Retrieved and formatted by PlainEnviro

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the EPA Toxic Release Inventory (TRI). Consult a qualified professional before making decisions based on this data.