| 환경 거동 | TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 24(SRC), determined from a structure estimation method(2), indicates that 1,2-butadiene is expected to have very high mobility in soil(SRC). Volatilization of 1,2-butadiene from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 0.097 atm-cu m/mole(SRC), using a fragment constant estimation method(3). The potential for volatilization of 1,2-butadiene from dry soil surfaces may exist(SRC) based upon a vapor pressure of 1,260 mm Hg(4).AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 24(SRC), determined from an estimation method(2), indicates that 1,2-butadiene is not expected to adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 0.097 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 1 and 70 hours, respectively(SRC). According to a classification scheme(5), an estimated BCF of 8(SRC), from an estimated log Kow of 2.06(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). No biodegradation data were located for 1,2-butadiene(SRC), but the biodegradation half-life of 1,3-butadiene in aerobic waters has been reported as 7 days and the half-life in anaerobic waters was reported as 28 days(8). These data suggest that 1,2-butadiene will also be biodegraded in aquatic systems(SRC).ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,2-butadiene, which has a vapor pressure of 1,260 mm Hg at 25 °C(2), is expected to exist solely as a gas in the ambient atmosphere. Gas-phase 1,2-butadiene is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and ozone molecules(SRC). The half-life for the reaction in air with hydroxyl radicals is estimated to be 15 hours(SRC), calculated from its rate constant of 2.6X10-11 cu cm/molecule-sec(3). The half-life for the reaction in air with ozone is estimated to be 12 days(SRC), calculated from its rate constant of 9.75X10-19 cu cm/molecule-sec(SRC), estimated with a structure estimation method(4). The gas phase reaction of 1,2-butadiene with nitrate radicals may be an important atmospheric removal process in urban areas at night(5), but the rate of this reaction is not known. |
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