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

Propanes

1,2-Dibromo-3-Chloropropane

1,2-Dibromo-3-Chloropropane 1,2-Dibromo-3-chloropropane (DBCP, CAS# 96-12-8) has a vapor pressure of 0.58 mm Hg at 20oC (ATSDR 1992) and is a class IIIA combustible liquid (NIOSH 2005). ATSDR (1992) estimates the log Koc of DBCP as 2.17, the log Kow as 2.26, and the Henry's constant as 1.47 e-4 atm-m3/mole (20oC). The solubility of DBCP is about 1230 mg/L at 20oC (ATSDR 1992), and its specific gravity is about 2.17. ATSDR (Agency for Toxic Substances and Disease Registry) has developed a toxicological profile for DBCP that contains a useful summary tableAdobe PDF Logo of the physical properties of DBCP.

The relatively low calculated Koc value for DBCP in soil indicates that the compound is likely to move quickly through soil and sediment (ATSDR 1992). In the near-surface soil, volatilization is its main fate (HSDB).

DBCP is expected to volatilize rapidly from water. Modeling suggests that the half life of DBCP in a river one meter deep is about 13.5 hours, and about eight days in a pond (ATSDR 1992).

Because of its low Kow, bioaccumulation of DBCP is not expected to occur to any significant extent. Uptake by plant roots has been demonstrated. Microbial action can degrade DBCP under aerobic and anaerobic conditions, but the rate is expected to be slow (ATSDR 1992). Deely et al. (1991) indicate that hydrolysis is the primary mechanism for dehalogenation of DBCP in groundwater.

When released to the atmosphere, hydroxyl radicals are expected to degrade DBCP with a half life of about 36 days (ATSDR 1992). The transformation products from the reaction of DBCP with hydroxyl radical in the atmosphere include 1,2-dibromopropanol, chlorobromopropanol, and 1-bromo-3-chloro-2-propanone (HSDB). Direct photolysis is not expected to occur (ATSDR 1992).

References

1,2-Dibromo-3-Chloropropane
NIOSH Pocket Guide to Chemical Hazards.
National Institute of Occupational Safety and Health, NIOSH Publication Number 2005-149, 2005

1,2-Dibromo-3-Chloropropane, CASRN: 96-12-8
Hazardous Substances Data Bank (HSDB)
TOXNET, National Library of Medicine Web site.

Toxicological Profile for 1,2-Dibromo-3-Chloropropane
Agency for Toxic Substances and Disease Registry (ATSDR), 164 pp, 1992

Transformation and Sorption of 1,2-Dibromo-3-Chloropropane in Subsurface Samples Collected at Fresno, California
Deeley, G., M. Reinhard, and S. Stearns.
Journal of Environmental Quality 20(3):547-556(1991)
View abstract

For Further Information

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

Evaluation of Processes Affecting 1,2-Dibromo-3-Chloropropane (DBCP) Concentrations in Ground Water in the Eastern San Joaquin Valley, California: Analysis of Chemical Data and Ground-Water Flow and Transport Simulations
Burow, K., S. Panshin, N. Dubrovsky, D. Vanbrocklin, and G. Fogg.
U.S. Geological Survey Water-Resources Investigations Report 99-4059, 65 pp, 1999

Biodegradation and Adsorption of DBCP and the Mathematical Simulation of its Transport in Tropical Soils
Liu, C., N. Tamrakar, and R. Green.
Toxicity Assessment 2(3):239-252(1987)
View abstract