| Chemical Abstract Number (CAS #) |
87683
|
|---|
| Synonyms | Hexachlorobutadiene |
|---|
1,3-Butadiene, 1,1,2,3,4,4-hexachloro- |
| Analytical Methods |
EPA Method 502.2 |
|---|
EPA Method 503.1 |
EPA Method 524.2 |
EPA Method 612 |
EPA Method 625 |
EPA Method 8021A |
EPA Method 8120A |
EPA Method 8250A |
EPA Method 8260A |
| Molecular Formula | C4Cl6 |
|---|
| Use | SOLVENT FOR ELASTOMERS; HEAT-TRANSFER LIQ; TRANSFORMER &
HYDRAULIC FLUID; WASH LIQUOR FOR REMOVING C4 & HIGHER
HYDROCARBONS.
CHEM INT FOR FLUORINATED LUBRICANTS, RUBBER COMPOUNDS; FLUID FOR
GYROSCOPES
/Used in the USSR as a fumigant against Phylloxera on grapes. It is also used as a fumigant in
vineyards in France, Italy, Greece, Spain & Argentina.
Ultraviolet irradiation on hexachlorobutadiene monomer has been used to photopolymerize the
pin-hole free film.
The largest use of hexachlorobutadiene in USA in 1975 was for recovery of 'snift'
(chlorine-containing) gas in chlorine plants.
|
|---|
| Consumption Patterns | No information was available on the quantities used in USA.
|
|---|
| Apparent Color | CLEAR, COLORLESS LIQ.
|
|---|
| Odor | Faint turpentine like odor.
|
|---|
| Boiling Point | 215 DEG C AT 760 MM HG
|
|---|
| Melting Point | -21 DEG C
|
|---|
| Molecular Weight | 260.76
|
|---|
| Density | 1.5542 AT 20 DEG C
|
|---|
| Odor Threshold Concentration | 12 mg/cu m (odor low) 12 mg/cu m (odor high)
|
|---|
| Environmental Impact | Recent information on hexachlorobutadiene (HCBD) production was not available;
however, total USA production of hexachloro-1,3-butadiene was reported as 8.0 million
pounds/year in 1975 and losses of hexachloro-1,3-butadiene to the environment estimated at 0.1
million pounds/year. hexachloro-1,3-butadiene is used as a solvent for elastomers, heat-transfer
liquid, transformer and hydraulic fluids and as a wash liquor for removing C4 and higher
hydrocarbons. When released to soil surfaces, hexachloro-1,3-butadiene is expected to rapidly
evaporate. In aerobic zones of soil, Hexachloro-1,3-butadiene may biodegrade.
Hexachloro-1,3-butadiene will probably adsorb strongly to soils (estimated Koc = 5181) so
leaching will probably not be rapid except in sandy soils. Estimated half-lives for
hexachloro-1,3-butadiene are 3-30 days in river water and 30-300 days in lake and ground waters.
Because of its relatively high log Kow value (4.90), hexachloro-1,3-butadiene will sorb to
sediments, suspended sediments and biota. Henry's Law constants for hexachloro-1,3-butadiene
are 1.03X10-2 atm-cu m/mole (25 deg C) and 2.40X10-2 atm-cu m/mole (20 deg C); thus,
volatilization from unfrozen water will be rapid. It has a long half-life in the atmosphere with
estimates ranging from months to over a year. Therefore considerable dispersion is expected and
hexachloro-1,3-butadiene is found in remote areas of the globe far removed from emission
sources. Hexachloro-1,3-butadiene has been detected in a number of USA surface and drinking
waters. The highest exposure to hexachloro-1,3-butadiene will probably be in occupational
settings while the primary exposure of the public to hexachloro-1,3-butadiene will probably be
from drinking water.
|
|---|
| Environmental Fate | TERRESTRIAL FATE: When hexachlorobutadiene (HCBD) is released to soil surfaces,
evaporation is expected to be a significant transport mechanism (HCBD vapor pressure at 20 deg
C is 0.15 mm Hg ). HCBD may biodegrade in aerobic zones of soil based on aerobic
biodegradation studies in water . In anaerobic batch tests in water, HCBD did not
biodegrade ; thus, HCBD may not biodegrade in anaerobic zones of soil. No information was
found about HCBD adsorption to soil. The calculated Koc value for HCBD using equation 4.7 of
Lyman et al and a water solubility of 9.77 umole/l is 5181. Thus, HCBD will adsorb
strongly to organic material in soils and is not expected to rapidly migrate. However, migration
will be more rapid in sandy soils. Dune infiltration studies in the Netherlands indicate that HCBD
is mobile in sandy soil. Dune infiltration and effluent HCBD concentrations (respectively) were
0.02 and 0.01 ug/l in 1976 and 0.01 and 0.01 ug/l in 1977(6). Average residence time was 100
days. These results also suggest that degradation of HCBD under these conditions is very slow.
AQUATIC FATE: Hexachlorobutadiene (HCBD) may biodegrade in natural waters since 100%
HCBD degradation occurred in 7 days in an aerobic batch culture incubated at 25 deg C and
inoculated with settled domestic sewage . No information was found on HCBD biodegradation
rates in natural waters. Estimated half-lives for HCBD degradation are 3-30 days in river water
and 30-300 days in lake and ground waters . No information was found on hydrolysis or
photolysis. Because of its relativel high log Kow value (4.90 ), HCBD will sorb to sediments,
suspended sediments and biota. The mean bioconcentration factor (BCF) for rainbow trout
exposed to 0.10 ng/l and 3.4 ng/l of HCBD was 5800 and 17,000,respectively , which would
suggest extensive bioconcentration. The Henry's Law constant for HCBD at 25 deg C is
1.03X10-2 atm-cu m/mole . Another study reports a water/air partition coefficient of 0.97 at 20
deg C (2.4X10-2 atm-cu m/mole). These values indicate that HCBD will rapidly volatilize from
water (6).
ATMOSPHERIC FATE: In the atmosphere, hexachlorobutane should degrade primarily by
addition of photochemically derived hydroxyl radicals with its double bonds. By analogy with
tetrachloroethylene one would anticipate a half-life of 2 months. Using a mass balance approach a
half-life estimate of 1.6 was obtained for the northerm hemisphere. Therefore HCDB will be long
lived in the atmosphere and considerable dispersion would be expected.
|
|---|
| Drinking Water Impact | SURFACE: Hexachlorobutadiene (HCBD) was found at concentrations of 10 and 23
ug/l in water sampled beyond the boundries of two chemical plants . HCBD concentration in an
open waste treatment pond was 244 ug/l . Mississippi River water at Baton Rouge, LA
contained 1.9 ppb of HCBD . HCBD was found in the Ashtabula River (Ohio) at an unspecified
concentration . HCBD has also been detected in Lake Erie water . Grab samples of water
from Lake Ontario the Niagara River and the Detroit River contained mean HCBD concns of
0.01, 0.2, and 0.1 parts/per trillion, respectively . Betweeen 1982 and 1985 the average
concentration of HCBD in the Rhine River ranged from 0.01-0.1 ppb(6). The concentration of
HCBD in the North Sea off the coast of the Netherlands during 1983-1984 ranged from
<0.02-1.30 parts/per trillion, median 0.23 parts/per trillion(7). Since the concentration in the
Rhine River was 15 parts/per trillion, it was concluded that the river was a source of this
contaminant(7).
DRINKING WATER: Hexachlorobutadiene (HCBD) concentration ranged from 0.04 to 0.70
ug/l in New Orleans drinking water from the Carrollton water plant . The highest HCBD
concentration found in tap water from houses near Love Canal (Niagara Falls, NY) was 170
ng/l .
EFFL: Effluent from the Diamond Shamrock Corp in Deerpark, TX contained 2 ug/l
hexachlorobutadiene (HCBD) . HCDB was found to be discharged from the Niagara Falls
Sewage treatment plant . Concentrations were not indicated.
|
|---|
