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


U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

Dense Nonaqueous Phase Liquids (DNAPLs)

Chemistry and Behavior

Halogenated Alkanes

Ethanes

Ethylene Dibromide

 Ethylene DibromideEthylene Dibromide (EDB, CAS# 106-93-4) has a vapor pressure of 11 mmHg at 25oC (ATSDR 1992) and is a noncombustible liquid. (NIOSH 2005). Because its vapors are heavier than air, the compound tends to collect in low areas after a spill. Montgomery (1991) estimates the log Koc of EDB as 1.64, the log Kow as 1.76, and the Henry's constant as 6.5 e-4 atm-m3/mole (25oC). The solubility of EDB is about 4,000 mg/L at 20oC (NIOSH 1995), and its specific gravity is about 2.17. The Agency for Toxic Substances and Disease Registry (ATSDR) has developed a Toxicological Profile for EDB that contains a useful summary tableAdobe PDF Logo of the physical properties of EDB.

The relatively low calculated Koc value for EDB in soil indicates that EDB is likely to move quickly through soil and sediment; however, residual EDB sorbed to soil micropores can be resistant to biodegradation, chemical transformation, and mobilization (ATSDR 1992).

Volatilization is the most important removal process for EDB released to surface waters (ATSDR 1992). Modeling information in the Hazardous Substances Data Bank (HSDB) record for EDB suggests that the half life of EDB in a river one meter deep is about 2.6 hours, and about six days in a lake.

Because of EDB's low Kow, bioaccumulation is not expected to occur to any significant extent (ATSDR 1992). The compound can be degraded by microbial action under both aerobic and anaerobic conditions (ATSDR 1992 and Howard 1997).

When released to the atmosphere, hydroxyl radicals are expected to degrade EDB with a half life of about 40 days (ATSDR 1992). The transformation products from the reaction of EDB with hydroxyl radical in the atmosphere include formaldehyde, bromoethanol, hydrogen bromide, and formyl bromide (HSDB). Direct photolysis is not expected to occur (ATSDR 1992).

References

Ethylene Dibromide
NIOSH Pocket Guide to Chemical Hazards.
National Institute of Occupational Safety and Health, NIOSH Publication Number 2005-149, 2005

Groundwater Chemicals Desk Reference, Volume 2
Montgomery, J.
Lewis Publishers, Chelsea, MI, 1991, 944 pp

Handbook of Environmental Fate and Exposure Data for Organic Chemicals
Howard, P.
CRS Publishers, 528 pp, 1997

Ethylene Dibromide, CASRN: 106-93-4
Hazardous Substances Data Bank (HSDB)
TOXNET, National Library of Medicine Web site.

Toxicological Profile for 1,2-Dibromoethane
Agency for Toxic Substances and Disease Registry (ATSDR), 173 pp, 1992

For Further Information

DNAPL Site Evaluation Adobe PDF Logo
Cohen, R. and J. Mercer.
EPA 600-R-93-022, 369 pp, 1993