Isoprene

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Carcinogen

CAS Number: 78-79-5

Isoprene (CAS 78-79-5) 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, 74 facilities have filed TRI Form R disclosures for Isoprene, with a cumulative reported release volume of 819.1K 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 GOODYEAR TIRE & RUBBER CO in TX at 353.2K 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
819.1K lbs
Number of Facilities
74
Carcinogen
Yes
Persistent Bioaccumulative Toxicant
No

Which facilities release the most of this chemical?

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

# Facility Release (lbs)
1 Goodyear Tire & Rubber Co 353.2K lbs
2 Lyondell Chemical Co 90.5K lbs
3 Tsrc Specialty Materials LLC 52.0K lbs
4 Tm Deer Park Services LP 44.7K lbs
5 Exxonmobil Baton Rouge Chemical Plant (part) 38.0K lbs
6 Shell Chemical LP 31.5K lbs
7 Exxonmobil Baytown Chemical Plant (part) 24.9K lbs
8 Kraton Corp 24.1K lbs
9 Vp Racing Fuels Inc. 19.0K lbs
10 Contitech USA LLC 16.4K lbs
11 Chevron Phillips Chemical Co LP 14.8K lbs
12 Dixie Chemical Co Inc 14.7K lbs
13 Westlake Vinyls Inc 13.7K lbs
14 Dow Chemical Co Freeport Facility 7.5K lbs
15 Placid Refining Co LLC 7.3K lbs
16 Targa Downstream LLC - Galena Park Marine Terminal 7.0K lbs
17 Formosa Plastics Corp Texas 6.7K lbs
18 Kuraray America Inc Septon Bu 5.5K lbs
19 Exxonmobil Chemical Co Baytown Olefins Plant (part) 5.0K lbs
20 Lindau Chemicals Inc. 4.0K lbs
21 Chevron Products Co - Salt Lake Refinery 3.0K lbs
22 St Charles Operations (taft/star) Union Carbide Corp 2.8K lbs
23 Equistar Chemicals LP 2.8K lbs
24 Deer Park Refining LP 2.4K lbs
25 Bp Products Na Whiting Business Unit 2.4K lbs
26 Nova Chemicals Olefins LLC 2.3K lbs
27 Exxonmobil Refining & Supply Baytown Refinery (part) 1.8K lbs
28 Occidental Chemical Corp 1.4K lbs
29 Monument Chemical Port Arthur LLC 1.3K lbs
30 Equistar Chemicals Clinton Plant 1.2K lbs
31 Eastman Chemical Co Texas Operations 962 lbs
32 Dow Sabine River Operations 934 lbs
33 The Dow Chemical Co - Louisiana Operations 796 lbs
34 Systech Environmental Corp 755 lbs
35 Synthomer Adhesive Tehcnologies Eastoflex & East 648 lbs
36 Hf Sinclair Puget Sound Refining LLC 626 lbs
37 Chevron Products Co Pascagoula Refinery 570 lbs
38 Exxonmobil Oil Beaumont Refinery (part) 361 lbs
39 Nouryon Functional Chemicals LLC 330 lbs
40 Ohio Refining Co 205 lbs
41 Exxonmobil Oil Corp Chemical Plant (part) 186 lbs
42 Chevron Products Co Richmond Refinery 122 lbs
43 Shell Norco Chemical Plant 100 lbs
44 Huntsman Petrochemical LLC Port Neches Facility 80 lbs
45 Phillips 66 Terminal 65 lbs
46 Motiva - Port Arthur Chemicals 50 lbs
47 Invista Houston 46 lbs
48 Par Montana Billings Refinery 45 lbs
49 Tesoro Los Angeles Refinery-Carson Operations 44 lbs
50 Veolia Es Technical Solutions LLC Port Arthur Facility 42 lbs

Frequently Asked Questions

What is Isoprene?
Isoprene (CAS Number: 78-79-5) is a chemical tracked by the EPA Toxic Release Inventory (TRI) program. It is classified as a known or suspected carcinogen. 74 facilities in the United States report releasing this chemical to the EPA.
How much Isoprene is released in the U.S.?
U.S. facilities have reported a total of 819.1K lbs of Isoprene releases to the EPA Toxic Release Inventory across 74 facilities. Release quantities are self-reported estimates. This includes releases to air, water, land, and off-site transfers.
Is Isoprene harmful to health?
Isoprene 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 Isoprene?
The largest reported releasers of Isoprene include facilities across multiple states. Release data is self-reported annually to the EPA under the TRI program. View the full list of 74 facilities on this page.
What is the CAS number for Isoprene?
The CAS (Chemical Abstracts Service) Registry Number for Isoprene is 78-79-5. 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.