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1,4-Dioxane

CAS Number

123-91-1

Synonym

Diethylene ether; 1,4-Diethylene dioxide; 1,4-Dioxacyclohexane; Diethylene oxide; dioxyethylene ether; dioxane; p-Dioxane; [6]-crown-2

Occurrence/Use

Solvent, dehydrating agent; stabilizer in chlorinated solvents

Soil Screening

Last CHHSL revision: 
1/2005
CHHSL Comments: 

For chemical-specific screening levels for use in assessing contaminated sites, please see HHRA Note 3 (DTSC HERO). https://www.dtsc.ca.gov/assessingrisk/humanrisk2.cfm

Cancer Potency Information

Inhalation Unit Risk (μg/cubic meter)-1: 
7.7 E-6
Inhalation Slope Factor (mg/kg-day)-1: 
2.7 E-2
Oral Slope Factor (mg/kg-day)-1: 
2.7 E-2
Comments/References: 

OEHHA 2009.  Air Toxics Hot Spots Program Technical Support Document for Cancer Potencies.  Appendix B. Chemical-specific summaries of the information used to derive unit risk and cancer potency values. Updated 2011.

Air

Acute RELs

Acute REL (μg/m3): 
3000
Species: 
Human
Acute REL Toxicologic Endpoint: 
Respiratory and eye irritation
Acute REL Target Organs: 
Respiratory system, eyes
Severity: 
Mild
Last Acute REL Revision: 
1999
Acute Reference Exposure Levels Comments: 

Chronic REL

Chronic Inhalation REL (μg/m3): 
3000
Chronic Target Organs: 
Alimentary system, kidney, cardiovascular system
Human Data: 
No
Last Chronic REL Revision: 
2000
Chronic Reference Exposure Levels Comments: 

Proposition 65

Chemical Status

Cancer: 
Currently listed

Cancer

Listed as causing: 
Cancer
Date of Listing: 
01/01/1988
Basis for Listing: 
State's Qualified Experts

Safe Harbor Levels

Cancer
No Significant Risk Level (NSRL): 
30 µg/day

Water

California Public Health Goals Data

Notification Level (μg/L): 
1
Notification Level - Download: 
California PHG Comments: