1,4-Dioxane

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Carcinogen

CAS Number: 123-91-1

1,4-Dioxane (CAS 123-91-1) 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, 82 facilities have filed TRI Form R disclosures for 1,4-Dioxane, with a cumulative reported release volume of 4.8M lbs. The chemical carries a carcinogen classification in the TRI database, based on assessments from EPA, IARC, or the National Toxicology Program. The largest individual disclosure in the current dataset comes from HUNTSMAN INTERNATIONAL LLC in TX at 2.0M 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
4.8M lbs
Number of Facilities
82
Carcinogen
Yes
Persistent Bioaccumulative Toxicant
No

Which facilities release the most of this chemical?

Facilities with the largest reported releases of 1,4-Dioxane. Up to 50 shown.

# Facility Release (lbs)
1 Huntsman International LLC 2.0M lbs
2 Union Processing Systems LLC 1.3M lbs
3 Chemical Waste Management of the Northwest Inc. 277.1K lbs
4 Coim USA Inc 182.2K lbs
5 Apg Polytech LLC 156.5K lbs
6 Tm Deer Park Services LP 152.7K lbs
7 Alpek Polyester USA Llc-Columbia Site 136.4K lbs
8 Stepan Co Millsdale Road 105.6K lbs
9 Indorama Ventures 95.4K lbs
10 Alpek Polyester USA LLC Cooper River Plant 66.3K lbs
11 Eastman Chemical Co Tennessee Operations 43.5K lbs
12 Vickery Environmental Inc. 40.1K lbs
13 Union Carbide Corp Seadrift Plant 26.8K lbs
14 Alpek Polyester USA LLC 24.5K lbs
15 Eq Detroit Inc 24.5K lbs
16 St Charles Operations (taft/star) Union Carbide Corp 23.0K lbs
17 Emerald Services Inc 17.0K lbs
18 Nan Ya Plastics Corp America 11.8K lbs
19 Stepan Co 11.8K lbs
20 Mitsubishi Chemical America Inc. 9.1K lbs
21 Alpek Polyester Mississippi Inc 7.0K lbs
22 Auriga Polymers Inc-Spartanburg Facility 6.7K lbs
23 Saint Gobain Abrasives Inc 5.0K lbs
24 Eastman Chemical Co South Carolina Operations 4.2K lbs
25 Starpet Inc 3.5K lbs
26 Buzzi Unicem Usa-Greencastle Plant 2.9K lbs
27 E R Carpenter LP 2.3K lbs
28 Basf Corp 2.1K lbs
29 Systech Environmental Corp 2.0K lbs
30 Lexmark International Inc 1.8K lbs
31 Veolia Wts Solutions USA Inc. 1.5K lbs
32 Lacamas Laboratories Inc 1.3K lbs
33 Curia Missouri-Springfield (formerly Amri-Missouri Inc.) 1.1K lbs
34 Corden Pharma Colorado Inc 1.0K lbs
35 Cambrex Charles City Inc 998 lbs
36 Huntsman Petrochemical LLC Port Neches Facility 887 lbs
37 Phenomenex Inc. 862 lbs
38 Patheon Api Services Inc. 814 lbs
39 Eco-Services Operations 778 lbs
40 Clean Harbors Environmental Services Inc 453 lbs
41 Giant Cement Co 420 lbs
42 Solvay USA LLC 316 lbs
43 US Army Picatinny Arsenal 260 lbs
44 Polynt Composites USA Inc. 259 lbs
45 Microdyn-Nadir Corp 255 lbs
46 Curia Wisconsin Inc. 209 lbs
47 Buckman Laboratories Inc. 208 lbs
48 Clean Harbors el Dorado LLC 127 lbs
49 Pci Synthesis 110 lbs
50 Tedia Co LLC 98 lbs

Frequently Asked Questions

What is 1,4-Dioxane?
1,4-Dioxane (CAS Number: 123-91-1) is a chemical tracked by the EPA Toxic Release Inventory (TRI) program. It is classified as a known or suspected carcinogen. 82 facilities in the United States report releasing this chemical to the EPA.
How much 1,4-Dioxane is released in the U.S.?
U.S. facilities have reported a total of 4.8M lbs of 1,4-Dioxane releases to the EPA Toxic Release Inventory across 82 facilities. Release quantities are self-reported estimates. This includes releases to air, water, land, and off-site transfers.
Is 1,4-Dioxane harmful to health?
1,4-Dioxane is classified as a known or suspected carcinogen by the EPA, based on evaluations from IARC, NTP, or EPA itself. 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 1,4-Dioxane?
The largest reported releasers of 1,4-Dioxane include facilities across multiple states. Release data is self-reported annually to the EPA under the TRI program. View the full list of 82 facilities on this page.
What is the CAS number for 1,4-Dioxane?
The CAS (Chemical Abstracts Service) Registry Number for 1,4-Dioxane is 123-91-1. CAS numbers are unique numerical identifiers assigned to every chemical substance described in the open scientific literature. This identifier is used to search scientific databases and regulatory filings.

Health Information

Carcinogen Classification: This chemical is classified as a known or suspected carcinogen by the EPA under the Toxic Release Inventory program. This classification is based on evaluations by agencies including the International Agency for Research on Cancer (IARC), the National Toxicology Program (NTP), and the EPA itself.

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.