| 환경 거동 | TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 276(SRC), determined from a structure estimation method(2), indicates that 2,2,4-trimethyl-2-pentene is expected to have moderate mobility in soil(SRC). Volatilization of 2,2,4-trimethyl-2-pentene from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 0.881 atm-cu m/mole(SRC), using a fragment constant estimation method(3). The potential for volatilization of 2,2,4-trimethyel-2-pentene from dry soil surfaces may exist(SRC) based upon a vapor pressure of 35.9 mm Hg(4). On exposure of 2,4,4-trimethyl-2-pentene to activated sludge in the Warburg respirometer test using oxygen uptake as a measure of oxidation, a theoretical oxygen demand for 6,12, and 24 hour exposures was 0.4%, 0.3%, and 0.7%, respectively suggesting that biodegradation in soil and water is expected to be slow(5).AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 276(SRC), determined from a structure estimation method(2), indicates that 2,2,4-trimethyl-2-pentene is expected to slightly adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is expected to occur rapidly(3) based upon an estimated Henry's Law constant of 0.881 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Volatilization half-lives for a model river and model lake are 3.1 and 101 hrs, respectively(SRC), using an estimation method(3). On exposure of 2,4,4-trimethyl-2-pentene to activated sludge in the Warburg respirometer test using oxygen uptake as a measure of oxidation, a theoretical oxygen demand for 6,12, and 24 hour exposures was 0.4%, 0.3%, and 0.7%, respectively suggesting that biodegradation in soil and water is expected to be slow(5). According to a classification scheme(4), an estimated BCF of 240(3,SRC), from an estimated log Kow of 4.0(6,SRC), suggests the potential for bioconcentration in aquatic organisms is high.ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,2,4-triemthyl-2-pentene, which has a vapor pressure of 35.9 mm Hg at 25 °C(2), is expected to exist solely in the vapor phase in the ambient atmosphere. Vapor-phase 2,2,4-triemthyl-2-pentene is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC)the half-life for this reaction in air is estimated to be 4.4 hrs(SRC), calculated from its estimated rate constant of 8.77X10-11 cu cm/molecule-sec at 25 °C(SRC)determined using a structure estimation method(3). The second-order rate constant for the vapor-phase reaction of 2,2,4-trimethyl-2-pentene with photochemically-produced ozone is 1.39X10-16 cu cm/molecule sec at 296.6 Kthe half-life for this reaction is 2 hours(4). Reaction of vapor-phase 2,2,4-trimethyl-2-pentene with nitrate radical may be an important night-time loss process based on its molecular structure(5). |
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