| Chemical Abstract Number (CAS #) |
103651
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| Synonyms | n-Propylbenzene |
| Analytical Methods |
EPA Method 502.2 |
EPA Method 503.1 |
EPA Method 524.2 |
EPA Method 8021A |
| Molecular Formula | C9H12 |
| Use | IN TEXTILE DYEING & PRINTING; AS SOLVENT FOR CELLULOSE ACETATE
IN MFR OF METHYLSTYRENE
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| Apparent Color | COLORLESS LIQUID
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| Boiling Point | 159.2 DEG C AT 760 MM HG
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| Melting Point | -99.2 DEG C
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| Molecular Weight | 120.19
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| Density | SP GR: 0.8620 @ 20 DEG C/4 DEG C
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| Sensitivity Data | IRRITATING TO MUCOUS MEMBRANES, EYES, NOSE, THROAT & SKIN.
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| Environmental Impact | n-Propylbenzene occurs naturally in petroleum and bituminous coal. It is released to the
atmosphere in emissions from combustion sources such as incinerators, gasoline engines, and
diesel engines. Solvent evaporation, landfill leaching, and general use of asphalt also release it to
the environment. If released to the atmosphere, n-propylbenzene will degrade in the vapor-phase
by reaction with photochemically produced hydroxyl radicals (estimated half-life of 2.7 days). If
released to soil or water, n-propylbenzene will probably biodegrade. The results of various
biodegradation screening studies suggest that n-propylbenzene can biodegrade in the
environment. Biodegradation is the only identifiable degradation process in soil. Photosensitized
photolysis may contribute to degradation in water. Volatilization may be the dominant removal
mechanism in many environmental surface waters. Occupational exposure to n-propylbenzene
occurs through dermal contact and inhalation of vapor. The general population is continually
exposed to n-propylbenzene through inhalation since it occurs ubiquitously in the atmosphere.
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| Environmental Fate | TERRESTRIAL FATE: The results of various biodegradation screening studies indicate
that n-propylbenzene can biodegrade in the environment. Biodegradation is the only identifiable
degradation process in soil. Measured and estimated Koc values ranging from 495 to 725 suggest
that n-propylbenzene has low to medium soil mobility(1-3); therefore, some leaching in soil is
possible. The detection of n-propylbenzene in landfill leachates demonstrates that leaching can
occur.
AQUATIC FATE: The results of various biodegradation screening studies suggest that
n-propylbenzene can biodegrade in the environment. In addition to biodegradation,
photosensitized photolysis may contribute to the environmental degradation of n-propylbenzene in
natural water . Volatilization will be an important transport process. Volatilization half-lives
(which exclude adsorption) of 3.3 and 39 hr can be estimated for a model river and model
environmental pond, respectively(2,3,SRC); if maximum predictable adsorption is included in the
pond simulation, the volatilization half-life increases to 10 days(3,SRC). Volatilization half-lives
of 1.3-19 days have been predicted for the Narraganset Bay near RI where volatilization is
expected to be the major removal process . Aquatic hydrolysis is not an important fate
process.
ATMOSPHERIC FATE: Based upon a vapor pressure of 3.42 mm Hg at 25 deg C ,
n-propylbenzene is expected to exist almost entirely in the vapor-phase in the ambient
atmosphere(2,SRC). The dominant degradation process in the atmosphere is the vapor-phase
reaction with photochemically produced hydroxyl radicals which has an estimated half-life of 2.7
days(3,SRC). The detection of n-propylbenzene in rainwater samples suggests that physical
removal from the atmosphere by wet deposition is possible.
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| Drinking Water Impact | DRINKING WATER: Results of the USEPA Groundwater Supply Survey (finished
water supplies that use groundwater sources) found that n-propylbenzene was detected in only
one of 945 sources (conc of 0.98 ug/L in the one source) that were surveyed from throughout the
US . Drinking water samples collected from Miami, FL and Cincinnati, OH during 1974 and
1975 had respective n-propylbenzene concs of 0.05 and 0.01 ug/L . A drinking water sample
from Cincinnati, OH in Feb 1980 had a n-propylbenzene concn of 33 ng/L .
SURFACE WATER: The n-propylbenzene concn in Lake Constance varied from 4 to 132 ng/L;
concns were observed to increase with increasing boat traffic .
GROUND WATER: A well water sample collected near a landfill in Delaware had an
n-propylbenzene conc of 0.5 ug/L .
SEAWATER: n-Propylbenzene was detected (concn not reported) in seawater samples collected
from the Narragansett Bay near RI during summer and winter monitoring between 1979 and
1981 . The concn of n-propylbenzene ranged from 0.2-2.9 ng/L (avg 1.1) at a coastal site in
MA during a 15 month monitoring period between 1977 and 1978 .
RAIN/SNOW: Trace levels (concn not reported) of n-propylbenzene were detected in rainwater
collected in Los Angeles, CA on Mar 26, 1982 .
EFFL: n-Propylbenzene has been qualitatively detected in various wastewaters from the
following industries: petroleum refining, textile mills, auto and other laundries, plastics mfg, and
publicly owned treatment works . Based upon dynamometer tests, the avg n-propylbenzene
emission rate from gasoline-powered engines is 1.2 mg/km . Leachate from 4 hazardous waste
landfills in Germany contained n-propylbenzene levels of 10-700 ug/L . An n-propylbenzene
concn of 69 mg/cu m was detected in gas emissions from a landfill in Great Britain . A aqueous
effluent from a US petroleum refinery had a n-propylbenzene concn of 13 ng/g .
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