Mercury Compounds

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PBT

EPA TRI Category Code: N458

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.

Across the United States, 963 facilities have filed TRI Form R disclosures for Mercury Compounds, with a cumulative reported release volume of 5.7M lbs. The chemical is not flagged as a carcinogen in the TRI classification set. It is also listed as a persistent, bioaccumulative, and toxic (PBT) substance, a category subject to lower reporting thresholds and elevated regulatory concern. The largest individual disclosure in the current dataset comes from BALD MOUNTAIN MINE in NV at 1.1M 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.

Release Summary

Total Releases
5.7M lbs
Number of Facilities
963
Carcinogen
No
Persistent Bioaccumulative Toxicant
Yes

Which facilities release the most of this chemical?

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

# Facility Release (lbs)
1 Bald Mountain Mine 1.1M lbs
2 Nevada Gold Mines LLC - Goldstrike Mines Inc 805.9K lbs
3 Kg Mining (bald Mountain) Inc South Operations Area (soa) 759.6K lbs
4 Gold Bar Mine 689.2K lbs
5 Red Dog Operations 588.3K lbs
6 Nevada Gold Mines Llc- Long Canyon Mine 229.2K lbs
7 Hycroft Mine 206.3K lbs
8 Smoky Valley Common Operation 146.1K lbs
9 Freeport-McMoran Bagdad Inc 121.2K lbs
10 Kennecott Utah Copper Mine Concentrators & Power Plant 103.1K lbs
11 Marigold Mining Co 96.5K lbs
12 Robinson Nevada Mining Co 95.0K lbs
13 Fiore Gold Pan Mine 70.2K lbs
14 Apma 9156-GIL Exploration Site 69.6K lbs
15 Mesquite Mine 55.6K lbs
16 Hecla Greens Creek Mining Co 45.8K lbs
17 Nevada Gold Mines LLC - Arturo Mine 45.3K lbs
18 Freeport-McMoran Morenci Inc 33.4K lbs
19 Clean Harbors San Jose LLC 30.6K lbs
20 Wharf Resources 25.9K lbs
21 Apl Engineered Materials Inc 14.8K lbs
22 Freeport-McMoran Sierrita Inc 13.1K lbs
23 Ash Grove Cement Co 11.2K lbs
24 Fort Knox Mine 10.1K lbs
25 U.S. Silver - Idaho Inc 9.0K lbs
26 Isabella Pearl Mine (006-240-02) 7.6K lbs
27 Equinox Gold Corp Castle Mountain Venture Castle Mountain 6.9K lbs
28 Wayne Disposal Inc 6.5K lbs
29 American Electric Power Amos Plant 6.4K lbs
30 J R Simplot Co Don Sid Ing 5.3K lbs
31 White Springs Agricultural Chemicals Inc. - Nutrien 5.2K lbs
32 Mosaic Fertilizer Llc-New Wales Plant 5.2K lbs
33 Granite Creek Mine 4.9K lbs
34 Cardinal Plant 4.4K lbs
35 Harrison Power Station 4.3K lbs
36 Oak Grove Steam Electric Station 3.6K lbs
37 Befesa Zinc US Inc. 3.5K lbs
38 Clean Harbors Grassy Mountain LLC 3.5K lbs
39 St Lawrence Zinc Co Balmat 4 Mine & Mill 3.4K lbs
40 Oceanagold Haile Gold Mine 3.3K lbs
41 Compass Minerals Ogden Inc 3.0K lbs
42 Oak Creek Site 3.0K lbs
43 Springerville Generating Station 2.6K lbs
44 Meridian Bioscience Inc. 2.5K lbs
45 Gibson Generating Station 2.4K lbs
46 Clean Harbors Lone Mountain LLC Lone Mountain Facility 2.4K lbs
47 Heidelberg Materials US Cement LLC 2.4K lbs
48 Tesoro Alaska - Kenai Refinery 2.4K lbs
49 Carboline Global Inc. 2.4K lbs
50 Mosaic Fertilizer LLC Uncle Sam Plant 2.4K lbs

Frequently Asked Questions

What is Mercury Compounds?
Mercury Compounds (EPA TRI Category Code: N458) is a chemical tracked by the EPA Toxic Release Inventory (TRI) program. It is classified as a persistent bioaccumulative toxicant (PBT). 963 facilities in the United States report releasing this chemical to the EPA.
How much Mercury Compounds is released in the U.S.?
U.S. facilities have reported a total of 5.7M lbs of Mercury Compounds releases to the EPA Toxic Release Inventory across 963 facilities. Release quantities are self-reported estimates. This includes releases to air, water, land, and off-site transfers.
Is Mercury Compounds harmful to health?
Mercury Compounds is not classified as a carcinogen in the EPA TRI database. It is classified as a persistent bioaccumulative toxicant (PBT), meaning it persists in the environment and accumulates in food chains. Health effects depend on exposure levels, duration, and route. For specific health questions, consult a toxicologist or your local health agency.
Which facilities release the most Mercury Compounds?
The largest reported releasers of Mercury Compounds include facilities across multiple states. Release data is self-reported annually to the EPA under the TRI program. View the full list of 963 facilities on this page.
Why is 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 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 Editorial

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.