Turpentine

CAS RN: 8006-64-2

Environmental Fate

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1000(SRC), determined from a structure estimation method(2) for alpha- and beta-pinene which are the two major chemical constituents of turpentine(3), indicates that turpentine is expected to have low mobility in soil(SRC). Volatilization of turpentine from moist soil surfaces is expected to be an important fate process(SRC) given Henry's Law constants of 0.134 and 0.0679 atm-cu m/mole for alpha- and beta-pinene(4). Turpentine is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.9-5 mm Hg at 20 deg C(5). Screening tests have demonstrated that alpha- and beta-pinene are biodegradable, but not always readily biodegradable(3). A mixture consisting of 50.9% alpha-pinene and 36.8% beta-pinene biodegraded 52% after 28 days of incubation using a modified Strum test which classifies the mixture as not readily biodegradable(3). Soil contaminated by leakage of solvents and turpentine, sprayed with adapted microorganisms and monitoring over a 4-5 month period revealed that the alkylated aromatics and turpentine were being biodegraded(6). These tests suggest that biodegradation may be an important environmental fate process in soil(SRC).
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1000(SRC), determined from a structure estimation method(2) for alpha- and beta-pinene which are the two major chemical constituents of turpentine(3), indicates that turpentine is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(4) based upon Henry's Law constants of 0.134 and 0.0679 atm-cu m/mole for alpha- and beta-pinene(5). Using these Henry's Law constants and an estimation method(4), volatilization half-lives for a model river and model lake are 3.4 hours and 4.6 days, respectively(SRC). Volatilization from water may be attenuated somewhat due to adsorption to suspended solids and sediment(SRC). According to a classification scheme(6), estimated BCF values of 714 and 258 for alpha- and beta-pinene(SRC), from log Kow values of 4.83 and 4.16, respectively(3), suggest the potential for bioconcentration in aquatic organisms is high(SRC). Screening tests have demonstrated that alpha- and beta-pinene are biodegradable, but not always readily biodegradable(3). A mixture consisting of 50.9% alpha-pinene and 36.8% beta-pinene biodegraded 52% after 28 days of incubation using a modified Strum test which classifies the mixture as not readily biodegradable(3). A 92% of theoretical BOD of alpha-pinene in 4 weeks using activated sludge in the Japanese MITI test(7) suggests that biodegradation is an important environmental fate process in water(SRC). The terpene hydrocarbons in turpentine are not expected to hydrolyze in water since these substances lack functional groups that hydrolyze under environmental conditions(3). The constituent compounds in turpentine are olefinic compounds(3) and olefins in surface waters exposed to sunlight react with photo-oxidants (such as hydroxyl radicals, peroxy radicals and singlet oxygen) with a half-life on the order of 25 days(8).
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), turpentine, which has a vapor pressure of 1.9-5 mm Hg at 20 deg C(2) is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase turpentine 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 5.5-7.3 hours(SRC), calculated from the rate constants of 5.30X10-11 and 7.05X10-11 cu cm/molecule-sec at 25 deg C for alpha- and beta-pinene(3,4) which are the primary chemical constituents of turpentine(5). Vapor-phase turpentine is also degraded in the atmosphere by reaction with ozone(SRC); the half-life for this reaction in air is estimated to be 3.4-12.3 hours(SRC), calculated from the rate constants of 8.11X10-17 and 2.24X10-17 cu cm/molecule-sec at 25 deg C for alpha- and beta-pinene(4). In addition, vapor-phase turpentine is degraded in the atmosphere by reaction with nitrate radicals(SRC); the half-life for this reaction in air is estimated to be a 0.13-0.30 hours(SRC), calculated from the rate constants of 6.16X10-12 and 2.51X10-12 cu cm/molecule-sec at 25 deg C for alpha- and beta-pinene(4). Nitrate radicals exist primarily in the night-time atmosphere(6); therefore, night-time degradation appears to be a major environmental sink for turpentine constituents(SRC).
Find more information on this substance at: PubChem, PubMed