Technical Factsheet on: ETHYLENE DIBROMIDE (EDB)
List of Contaminants
As part of the Drinking Water and Health pages, this fact sheet is part of a larger publication:
National Primary Drinking Water Regulations
Drinking Water Standards
MCLG: zero mg/l
MCL: 0.00005 mg/l
HAL(child): 1 day: 0.008 mg/l; 10-day: 0.008 mg/l
Health Effects Summary
Acute: EPA has found ethylene dibromide (EDB) to potentially
cause a variety of acute health effects, including damage to the
liver, stomach, and adrenal cortex along with significant
reproductive system toxicity, particularly the testes.
Drinking water levels which are considered "safe" for short-term
exposures: For a 10-kg (22 lb.) child consuming 1 liter of water
per day, a one-day exposure of 0.008 mg/L or a ten-day exposure
to 0.008 mg/L.
Chronic: A lifetime exposure to EDB at levels above the MCL has
the potential to damage the respiratory system, nervous system,
liver, heart, and kidneys.
Cancer: There is some evidence that EDB may have the potential
to cause cancer from a lifetime exposure at levels above the MCL.
Usage Patterns
Ethylene dibromide is mainly used (83% of all use) as a scavenger
for lead in anti-knock gasoline mixtures, particularly in
aviation fuel. Other uses (17%) include: solvent for resins,
gums, and waxes; in waterproofing preparations; as a chemical
intermediate in the synthesis of dyes and pharmaceuticals; and as
a fumigant, insecticide, nematicide for grains and fruit.
Release Patterns
Monitoring of ethylene bromide in ocean water and ocean air
suggests that ethylene bromide may be formed naturally in the
ocean as a result of macro algae growth.
Artificial releases include: evaporative losses associated with
the use, storage, and transport of leaded gasoline in which it is
used as a lead scavenger; spills and leaking storage tanks for
leaded gasoline; exhaust from vehicles using leaded gasoline;
emissions from its former use as a fumigant for soil, grain,
fruits, vegetables, tobacco, and seed uses which have recently
been restricted or discontinued; wastewater and emissions from
its use as a solvent for resins, gums, and waxes and; as a
chemical intermediate in the synthesis of dyes and
pharmaceuticals; residue in fumigated food.
From 1987 to 1993, according to the Toxics Release Inventory EDB
releases to land totalled 2,670 lbs., and water releases totalled
2,554 lbs. These releases were primarily from facilities
classified as petroleum refineries. The largest of these releases
occurred in California and Missouri.
Environmental Fate
When spilled on land or applied to land during soil fumigation,
ethylene dibromide will exhibit low to moderate adsorption and
has been found in groundwater. Measured KOC values range from 14
to 160. However, in typical fields where gaseous ethylene
dibromide has been used as a soil fumigant, 99% of the ethylene
dibromide used in fumigation is in the sorbed state.
Persistence can vary greatly from soil to soil. In one laboratory
screening study using 100 soils, half-lives ranging from 1.5 to
18 weeks were determined. In one field, ethylene bromide was
detected in soil 19 years after its last known application; the
long persistence was the result of entrapment in intraparticle
micropores of the soil. Low Koc values and detection in various
ground waters indicate that ethylene bromide will leach in soil.
The relatively high vapor pressure (11.2 mm Hg) indicates
evaporation will occur from soil surfaces.
In the atmosphere, ethylene dibromide will degrade by reaction
with photochemically produced hydroxyl radicals (half life 32
days).
The primary removal process for ethylene bromide in surface water
is volatilization. Under normal conditions, the volatilization
half-life from a typical river and lake are about one day and 5
days, respectively.
In ground waters (such as aquifers) where volatilization does not
occur, ethylene bromide can be degraded by biodegradation and
hydrolysis. Uncatalyzed hydrolysis is slow, with half-lives
reported of 6 yr at 25 deg C, to 13.2 yr at pH7 and 20 deg C. But
hydrolysis catalyzed by the presence of various natural
substances (such as HS ion) may be competitive with
biodegradation (half-life of 1-2 months). It reacts with
photochemically produced hydroxyl radicals with a half life of 32
days or a 2.2% loss per sunlit day. Ethylene bromide does not
directly photolyze when exposed to uv light between 300 and 400
nm.
Biodegradation can be a primary degradation process in soil. A
review of available biodegradation data pertaining to ethylene
bromide concluded that ethylene bromide is biotransformed fairly
readily in the environment; lifetimes can be as short as several
days in surface soils and as long as many months in aquifer
materials.
The measured log BCF in fish is < 1 indicating that ethylene
dibromide does not bioconcentrate in fish.
Chemical/ Physical Properties
CAS Number: 106-93-4
Color/ Form/Odor: Colorless, heavy liquid; mildly sweet
chloroform-like odor.
M.P.: 9.8 C B.P.: 131-132 C
Vapor Pressure: 11.2 mm Hg
Density/Spec. Grav.: 2.2 g/ml
Octanol/Water Partition (Kow): Log Kow = 135
Solubilities: 40 g/L of water at 25 C
Soil sorption coefficient (Koc): low to moderate; Koc = 14 to 160
Odor/Taste Thresholds: N/A
Bioconcentration Factor: <1 in fish
Henry's Law Coefficient: N/A
Trade Names/Synonyms: 1,2-Dibromoethane; EDB; Glycol dibromide;
Bromofume; Dowfume W 85; Aadibroom; Iscobrome-D; Nefis;
Pestmaster; EDB-85; Soilbrom; Soilfume; Kopfume
Other Regulatory Information
Monitoring For Ground/Surface Water Sources:
- Initial Frequency- 4 quarterly samples every 3 years
- Repeat Frequency- If no detections during initial round:
- 2 quarterly per year if serving >3300 persons;
- 1 sample per 3 years for smaller systems
- Triggers - Return to Initial Freq. if detect at > 0.00001 mg/L
Analysis:
| Reference Source |
Method Numbers |
| EPA 600/4-88-039 |
504.1; 551 |
Treatment- Best Available Technologies:
Granular Activated Charcoal
Toxic Release Inventory - Releases to Water and Land, 1987 to
1993 (in pounds):
| |
Water |
Land |
| TOTALS |
2,554 |
2,670 |
| Top Six States |
|
CA |
344 |
500
|
|
MS |
342 |
500
|
|
HI |
750 |
0
|
|
NJ |
0 |
700
|
|
TX |
110 |
466
|
|
PR |
500 |
0
|
| Top Industrial Sources |
|
Petroleum refining |
2,119 |
1,716
|
|
Industrial organic chemicals, fertilizers |
355 |
700
|
For Additional Information:
EPA can provide further regulatory and other general information:
EPA Safe Drinking Water Hotline - 800/426-4791
Other sources of toxicological and environmental fate data include:
Toxic Substance Control Act Information Line - 202/554-1404
Toxics Release Inventory, National Library of Medicine - 301/496-6531
Agency for Toxic Substances and Disease Registry - 404/639-6000
National Pesticide Hotline - 800/858-7378
List of Contaminants
|