U.S. EPA Contaminated Site Cleanup Information (CLU-IN)


U.S. Environmental Protection Agency
U.S. EPA's Technology Innovation Program

For more information on 1,4-Dioxane, please contact:

Marti Otto
Technology Assessment Branch

PH: (703) 603-8853 | Email: otto.martha@epa.gov

1,4-Dioxane

Toxicology

The greatest human health threat from 1,4-dioxane comes from repeated inhalation exposure to low concentrations of 1,4-dioxane among workers at industrial sites. Systemic effects reported among workers from inhalation exposures involve primarily the liver and kidneys. While evidence of carcinogenicity in laboratory animals is sufficient for EPA to classify 1,4-dioxane as a probable human carcinogen, inadequate evidence exists for the carcinogenicity of 1,4-dioxane in humans. EPA's Office of Air Quality Planning and Standards has placed 1,4-dioxane in the low category for carcinogenic hazard under Superfund's ranking. Acute inhalation of high levels of 1,4-dioxane may cause vertigo and irritation of the eyes, nose, throat, lungs and skin in mammals.

1,4-Dioxane is absorbed by all exposure routes, including lungs, skin and gastrointestinal tract. Distribution is rapid and uniform in lung, liver, kidney, spleen, colon and skeletal muscle tissue of laboratory animals. In rats, the percentage of covalent binding is highest in the liver, spleen and colon. 1,4-Dioxane is excreted mostly in the urine and through the lungs in expired air.

Although 1,4-dioxane has been detected in surface water and groundwater, human risks from lifetime exposures to contaminated water appear low. EPA estimates that, if an individual were to continuously drink water containing 1,4-dioxane at an average of 3.0 µg/L over his or her entire lifetime, that person would theoretically have no more than a one-in-a-million increased chance of developing cancer as a direct result of drinking water containing this chemical. Rats chronically exposed to 1,4-dioxane in drinking water exhibit liver and kidney damage. Limited data suggest that 1,4-dioxane does not bioaccumulate in fish or food chains.

Adapted from:

Adobe PDF Logo 1,4-Dioxane—Emerging Contaminant of Concern: Fact Sheet. Orange County Water District, CA.

Adobe PDF LogoMemorandum: 1,4-Dioxane Action Level
G. Alexeeff, California Office of Environmental Health Hazard Assessment, 1998.


Jump to a Subsection
Human Health | Ecological Impacts

Human Health

1,4-Dioxane
Re-Evaluation of Some Organic Chemicals, Hydrazine and Hydrogen Peroxide.
International Agency for Research on Cancer (IARC) Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man, Vol 71, p 589-602, 1999.

1,4-Dioxane (1,4-Diethyleneoxide): Air Toxics Hazard Summary
U.S. EPA, Technology Transfer Network, Air Toxics Website.

Adobe PDF Logo1,4-Dioxane, CAS No. 123-91-1
Report on Carcinogens, Tenth Edition. U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program, 5 pp, 2002.

1,4-Dioxane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals.

1,4-Dioxane (CASRN 123-91-1)
U.S. EPA, Integrated Risk Information System (IRIS).

Adobe PDF Logo1,4-Dioxane—Emerging Contaminant of Concern: Fact Sheet
Orange County Water District, CA.

Adobe PDF Logo 1,4-Dioxane: Hazardous Substance Fact Sheet
New Jersey Dept. of Health and Senior Services, 6 pp, 2002.
Contact: NJ Right-to-Know Program, 609-984-2202

Adobe PDF LogoBioassay of 1,4-Dioxane for Possible Carcinogenicity, CAS No. 123-91-1
U.S. Dept. Of Health, Education, and Welfare, National Institutes of Health.
NCI-CG-TR-80, 124 pp, 1978.

Adobe PDF LogoChronic Toxicity Summary: 1,4-Dioxane
California Office of Environmental Health Hazard Assessment, Chronic Reference Exposure Levels Adopted by OEHHA as of August 2003.

Adobe PDF LogoMemorandum: 1,4-Dioxane Action Level
G. Alexeeff.
California Office of Environmental Health Hazard Assessment, 7 pp, 1998.
Contact: Anna Fan, 510-622-3170

Opinion on the Results of the Risk Assessment of 1,4-DIOXANE - CAS No: 123-91-1, EINECS No: 204-661-8. Final Version, 5 November 1999 carried out in the framework of Council Regulation (EEC) 793/93 on the evaluation and control of the risks of existing substances 1. Opinion expressed at the 19th CSTEE plenary meeting, Brussels, 9 November 2000
European Commission on Public Health.

Safety (MSDS) Data for 1,4-Dioxane
Oxford University, Physical and Theoretical Chemistry Laboratory.

Table A-3-92: Chemical-Specific Inputs for 1,4-Dioxane (123-91-1)
Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities, Volume 2.
Appendix A: Chemical-Specific Data. U.S. EPA, 3 pp, 1998.

Adobe PDF LogoDraft Toxicological Profile for 1,4-Dioxane
Agency for Toxic Substances and Disease Registry, 263 pp, 2004

Toxicological Profile for 1,4-Dioxane
Agency for Toxic Substances and Disease Registry, 269 pp, 2006

TOXNET
National Library of Medicine Specialized Information Services.

This site contains a cluster of databases on toxicology, hazardous chemicals, and related areas, including the Hazardous Substances Data Bank (HSDB), Integrated Risk Information System (IRIS), and Toxics Release Inventory (TRI). The site supports simultaneous searching in multiple databases.

Ecological Impacts

Adobe PDF LogoChemicals in the Environment: Report on Environmental Survey and Wildlife Monitoring of Chemicals in FY2001
Environmental Health Department, Ministry of the Environment, Government of Japan, 126 pp, 2003.

Ecological Benchmark Tool
U.S. DOE, Oak Ridge National Laboratory.