Chemical Properties
Ethylene dibromide is a heavy, colorless liquid with a mild sweet odor, like chloroform. It
is also known as 1,2-dibromomethane. Ethylene dibromide is soluble in alcohols, ethers,
acetone, benzene, and most organic solvents, and slightly soluble in water. Ethylene dibromide
was once of dominant use, although its use has faded as an additive in leaded gasoline.
Ethylene dibromide (1,2-dibromoethane) reacts with lead residues to generate volatile
lead bromides. It has been used as a pesticide in soil and various crops. Exposure to ethylene
dibromide primarily occurs from its past use as an additive to leaded gasoline and as
a fumigant. Most of the uses of ethylene dibromide have been stopped in the United States for the control of moths and beehives, and as a preparation for dyes and waxes. Ethylene
dibromide was used as a fumigant to protect against insects, pests, and nematodes in citrus,
vegetable, and grain crops, and as a fumigant for turf, particularly on golf courses. In
1984, the US EPA banned its use as a soil and grain fumiga
General Description
A clear colorless liquid with a sweetish odor. Density 18.1 lb /gal. Slightly soluble in water. Soluble in most organic solvents and thinners. Noncombustible. Very toxic by inhalation, skin absorption or ingestion. Used as a solvent, scavenger for lead in gasoline, grain fumigant and in the manufacture of other chemicals.
Reactivity Profile
ETHYLENE DIBROMIDE(106-93-4) slowly decomposes in the presence of light and heat. Turns brown upon exposure to light. Corrosive to iron and other metals. May decompose upon contact with alkalis. Incompatible with oxidizing agents. Reacts with sodium, potassium, calcium, powdered aluminum, zinc, magnesium and liquid ammonia. May attack some plastics, rubber and coatings. May poison platinum catalysts [Hawley]. Reacts as an alkylating agent .
Air & Water Reactions
Slightly soluble in water. May react slowly with moisture.
Hazard
Probable carcinogen. Toxic by inhalation,
ingestion, and skin absorption; strong irritant to
eyes and skin.
Health Hazard
Exposures to ethylene dibromide cause adverse health effects and poisoning. Ethylene
dibromide is extremely toxic to humans. Long-term exposures of ethylene dibromide to laboratory
animals cause deleterious effects to the liver, kidney, and the testis, irrespective of
the route of exposure. Limited data on men occupationally exposed to ethylene dibromide
indicate that long-term exposure to ethylene dibromide can impair reproduction by damaging
sperm cells in the testicles. Several animal studies indicate that long-term exposure to
ethylene dibromide increases the incidences of a variety of tumors in rats and mice in both
sexes by all routes of exposure. The symptoms of toxicity include, but are not limited to, redness,
infl ammation, skin blisters, and ulcers on accidental swallowing/ingestion. Ethylene
dibromide has also been reported to cause birth defects in exposed humans.
Health Hazard
Local inflammation, blisters and ulcers on skin; irritation in lungs and organic injury to liver and kidneys; may be absorbed through skin.
Potential Exposure
Ethylene dibromide is used as a chemical intermediate; as a fumigant for ground pest control; as
a constituent of ethyl gasoline (anti-knock agent). It is also
used in fire extinguishers, gauge fluids, and waterproofing
preparations; and it is used as a solvent for celluloid, fats,
oils, and waxes. Pesticide not in use; TRI and/or IUR indicates importers or manufacturers are unlikely
First aid
Move victim to fresh air. Call 911 or emergency
medical service. Give artificial respiration if victim is not
breathing. Do not use mouth-to-mouth method if victim
ingested or inhaled the substance; give artificial respiration
with the aid of a pocket mask equipped with a one-way
valve or other proper respiratory medical device.
Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact
with substance, immediately flush skin or eyes with running
water for at least 20 minutes. For minor skin contact, avoid
spreading material on unaffected skin. Keep victim warm
and quiet. Effects of exposure (inhalation, ingestion or skin
contact) to substance may be delayed. Ensure that medical
personnel are aware of the material(s) involved and take
precautions to protect themselves. Medical observation is
recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for
pulmonary edema, a doctor or authorized paramedic may
consider administering a drug or other inhalation therapy.
Shipping
UN1605/154 Ethylene dibromide, Hazard Class:
6.1; Labels: 6.1-Poison Inhalation Hazard, Inhalation
Hazard Zone B
Incompatibilities
Reacts vigorously with chemically
active metals; liquid ammonia, strong bases; strong
oxidizers; causing fire and explosion hazard. Light, heat,
and moisture can cause slow decomposition, forming
hydrogen bromide. Attacks fats, rubber, some plastics and
coatings.
Description
Ethylene dibromide is a colorless nonflammable liquid or solid (below 10℃) with a sweet, chloroformlike odor. The minimum concentration detectable by odor is10 ppm. Molecular weight = 187.88; Specific gravity(H2O:1) = 2.17; Boiling point = 131℃; Freezing/Meltingpoint = 10℃; Relative vapor density (air = 1) = 6.5; Vaporpressure = 12 mmHg. Soluble in water
Waste Disposal
Controlled incineration with
adequate scrubbing and ash disposal facilities
Physical properties
Colorless liquid with a sweet, chloroform-like odor. Odor threshold concentration is 25 ppb
(quoted, Keith and Walters, 1992).
Uses
1,2-Dibromoethane (EDB) is used as a fumi gant for grains, in antiknock gasolines, as asolvent, and in organic synthesis.
Uses
Grain and fruit fumigant; insecticide.
Uses
Historically, the primary use of 1,2-dibromoethane has been as a lead scavenger in antiknock mixtures added to gasolines (IPCS 1996). Lead scavenging agents transform the combustion products of tetraalkyl lead additives to forms that are more likely to be vaporized from engine surfaces. In 1978, 90% of the 1,2-dibromoethane produced was used for this purpose (ATSDR 1992). Annual consumption of 1,2-dibromoethane in the United States has decreased since the U.S. Environmental Protection Agency banned the use of lead in gasoline.
Another major past use of 1,2-dibromoethane was as a pesticide and an ingredient of soil and grain fumigants and for post-harvest application to various vegetable, fruit, and grain crops (NTP 1982). It also was used to kill fruit flies on citrus fruits, mangoes, and papayas after harvest and in the soil to protect grasses in environments such as golf courses (ATSDR 1992). By 1984, EPA regulations had eliminated most of the uses of 1,2-dibromoethane as a pesticide in the United States. 1,2-Dibromoethane has been used as a chemical intermediate in the manufacture of resins, gums, waxes, dyes, and pharmaceuticals and as a high-density, nonflammable solvent in a number of applications. Small amounts of 1,2-dibromoethane have been used in the manufacture of vinyl bromide, which is used as a flame retardant (ATSDR 1992, HSDB 2009).
Uses
Soil and grain fumigant; as lead scavenger in anti-knock gasolines. Most of the uses of ethylene dibromide have been stopped in the United States; however, it is still used as a fumigant for treatment of logs for termites and beetles, for the control of moths and beehives, and as a preparation for dyes and waxes.
Definition
ChEBI: A bromoalkane that is ethane carrying bromo substituents at positions 1 and 2. It is produced by marine algae.
Preparation
1,2-Dibromoethane is manufactured via uncatalyzed, liquid-phase bromination of ethylene. Gaseous ethylene is brought into contact with bromine by various methods, allowing for dissipation of the heat of the reaction.
Fire Hazard
Ethylene dibromide is a noncombustible substance (NFPA rating = 0)
Flammability and Explosibility
Ethylene dibromide is a noncombustible substance (NFPA rating = 0).
Agricultural Uses
Fumigant, Nematicide: Not approved for use in EU countries. Not registered
for use in the U.S. Persons whose clothing or skin is contaminated
with liquid ethylene dibromide (above 10°C) can
secondarily contaminate others by direct contact or through
off-gassing vapor. Ethylene dibromide was used extensively
as a pesticide and an ingredient of soil, vegetable, fruit, and
grain fumigant formulations. Still used in India, South Africa
and other countries. There are 15 global suppliers.
Trade name
AADIBROOM®; EDB-85; FUMO-GAS®;
ISCOBROME D®; KOPFUME®; NEFIS®; NEPHIS®;
SOILFUME®; UNIFUME®
Carcinogenicity
1,2-Dibromoethane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Cancer Studies in Experimental Animals
Environmental Fate
Biological. Complete biodegradation of ethylene dibromide by soil cultures yielded
ethylene and bromide ions (Castro and Belser, 1968). A mutant of strain Acinetobacter
sp. GJ70 isolated from activated sludge degraded ethylene dibromide to ethylene glycol
and bromide ions (Janssen et al., 1987). When Methanococcus thermolithotrophicus,
Methanococcus deltae and Methanobacterium thermoautotrophicum were grown with
H2-CO2 in the presence of ethylene dibromide, methane and ethylene were produced (Belay
and Daniels, 1987).
In a shallow aquifer material, ethylene dibromide aerobically degraded to carbon
dioxide, microbial biomass and nonvolatile water-soluble compound(s) (Pignatello, 1986,
1987).
Soil. In soil and water, chemical- and biological-mediated reactions transform ethylene
dibromide in the presence of hydrogen sulfides to ethyl mercaptan and other sulfurcontaining
compounds (Alexander, 1981).
Groundwater. According to the U.S. EPA (1986) ethylene dibromide has a high potential
to leach to groundwater.
Chemical/Physical. In an aqueous phosphate buffer solution (0.05 M) containing
hydrogen sulfide ions, ethylene dibromide was transformed into 1,2-dithioethane and vinyl
bromide. The hydrolysis half-lives for solutions with and without sulfides present ranged
from 37 to 70 days and 0.8 to 4.6 years, respectively (Barbash and Reinhard, 1989).
Dehydrobromination of ethylene dibromide to vinyl bromide was observed in various
aqueous buffer solutions (pH 7–11) over the temperature range of 45 to 90°C. The
estimated half-life for this reaction at 25°C and pH 7 is 2.5 years (Vogel and Reinhard,
1986).
Ethylene dibromide may hydrolyze via two pathways. In the first pathway, ethylene
dibromide undergoes nucleophilic attack at the carbon-bromine bond by water forming
hydrogen bromide and 2-bromoethanol. The alcohol may react further through the formation
of ethylene oxide forming ethylene glycol (Kollig, 1993; Leinster et al., 1978). In the
second pathway, dehydrobromination of ethylene dibromide to vinyl bromide was observed
in various aqueous buffer solutions (pH 7–11) over the temperature range of 45 to 90°C.
The estimated hydrolysis half-life for this reaction at 25°C and pH 7 was 2.5 years (Vogel
and Reinhard, 1986).
The hydrolysis rate constant for ethylene dibromide at pH 7 and 25°C was determined
to be 9.9 ′ 10–6/hour, resulting in a half-life of 8.0 years (Ellington et al., 1988). At pH
5 and temperatures of 30, 45 and 60°C, the hydrolysis half-lives were 180, 29 and 9 days,
respectively. When the pH was raised to pH 7, the half-lives increased slightly to 410, 57
and 11 days at temperatures of 30, 45 and 60°C, respectively. At pH 9, the hydrolysis
half-lives were nearly identical to those determined under acidic conditions (Ellington et
al., 1986).
Anticipated products from the reaction of ethylene dibromide with ozone or hydroxyl
radicals in the atmosphere include bromoacetaldehyde, formaldehyde, bromoformaldehyde
and bromide radicals (Cupitt, 1980). In the atmosphere, ethylene dibromide is slowly
oxidized by peroxides and ozone. The half-life for these reactions is generally >100 days
(Leinster et al., 1978).
Metabolic pathway
The bacterial strain GP1 can utilize 1,2-dibromoethane
as a sole carbon and energy source. The first step in
1,2-dibromoethane is catalyzed by a hydrolytic
haloalkane dehalogenase and the resulting 2-
bromoethanol is rapidly converted to ethylene oxide,
preventing the accumulation of 2-bromoethanol and 2-
bromoacetaldehyde. However, the further metabolic
pathway(s) is unclear.
storage
work with EDB should be conducted in a fume hood to prevent exposure by inhalation, and appropriate impermeable gloves and safety goggles should be worn to prevent skin contact. Gloves and protective clothing should be changed immediately if EDB contamination occurs. Since EDB can penetrate neoprene and other plastics, protective apparel made of these materials does not provide adequate protection from contact with EDB.
Purification Methods
Wash the dibromide with conc HCl or H2SO4, then water, aqueous NaHCO3 or Na2CO3, more water, and dry it with CaCl2. Fractionally distil it. Alternatively, keep in daylight with excess bromine for 2hours, then extract with aqueous Na2SO3, wash with water, dry with CaCl2, filter and distil. It can also be purified by fractional crystallisation by partial freezing. Store it in the dark. [Beilstein 1 H 90, 1 I 28, 1 II 61, 1 III 182, 1 IV 158.]
Degradation
Due to its high volatility, the primary mode of dissipation of ethylene
dibromide (1) in water is via surface evaporation with an observed DT50
of 1-5 days. Ethylene dibromide hydrolysed slowly in pure water (pH
7) and sub-surface sediment with a calculated DT50 of 2.5-4 years at
25-60°C (Vogel and Reinhard, 1986; Haag and Mill, 1988). The DT50
values of ethylene dibromide in pH 5 solutions at 30, 45 and 60°C
were 180, 29 and 9 days, respectively (Ellington et al., 1988). Reductive
dehalogenation was the primary hydrolytic degradation reaction to yield
ethylene (2) and bromide ions (3) as terminal products.
Under field conditions, the hydrolytic degradation of ethylene dibromide
in Florida groundwater was slow (1.5-2 years), yielding ethylene
glycol (4) and bromide ions as terminal products (Weintraub et al.,
1986).
Castro and Belser (1985) reported the aqueous photolytic degradation
of ethylene dibromide, involving dehalogenation [yielding bromoethanol
(5)] and oxidation of ethylene (2) to ethylene oxide (6) which was further
hydrolysed to ethylene glycol (4).
In the vapour phase, ethylene dibromide reacted slowly with ozone
and/or hydroxyl radicals (DT50 >l00 days) to yield bromoacetaldehyde
(7), formaldehyde (8), bromof ormaldehyde (9) and bromide radicals
(Leinster et al., 1978; Cupitt, 1988).