2,4,6-Trimethylphenol

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 700(SRC), determined from a log Kow of 2.73(2) and a regression-derived equation(3), indicates that 2,4,6-trimethylphenol is expected to have low mobility in soil(SRC). Volatilization of 2,4,6-trimethylphenol from moist soil surfaces is expected to occur slowly(SRC) given an estimated Henry's Law constant of 3.1X10-6 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 0.05 mm Hg(4), and water solubility, 1,010 mg/l at 25 °C(5). 2,4,6-Trimethylphenol is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(4). 2,4,6-Trimethylphenol is expected to biodegrade slowly in soils(SRC) based on a theoretical BOD of 7 percent in the Japanese MITI test during a 4 week incubation period(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 700(SRC), determined from a log Kow of 2.73(2) and a regression-derived equation(3), indicates that 2,4,6-trimethylphenol is expected to adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is expected to occur(3) based upon an estimated Henry's Law constant of 3.1X10-6 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 0.05 mm Hg(4), and water solubility, 1,010 mg/l at 25 °C(5). Volatilization half-lives for a model river and model lake are 14 and 104 days, respectively(SRC), using an estimation method(3). 2,4,6-Trimethylphenol is expected to undergo photolysis in sunlit surface waters, with typical half-lives of about 4-11 hours(6). According to a classification scheme(7), BCF values of 3-10 measured in carp(8), suggest that bioconcentration in aquatic organisms is low(SRC). 2,4,6-Trimethylphenol, at an initial concn of 0.09 mg/l, underwent no degradation when incubated in coal tar-contaminated groundwater in an anaerobic digester for 8 weeks(9).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,4,6-trimethylphenol, which has a vapor pressure of 0.05 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2,4,6-trimethylphenol 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 16 hours(SRC) from its estimated rate constant of 2.4X10-11 cu cm/molecule-sec at 25 °C(SRC), determined from a fragment constant estimation method(3).

The Koc of 2,4,6-trimethylphenol is estimated as 700(SRC), using a log Kow of 2.73(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 2,4,6-trimethylphenol is expected to have low mobility in soil(SRC).

Estimated concentration of 2,4,6-trimethylphenol in air samples collected during Nov 1982 at the pilot-scale shale oil wastewater treatment plant of Occidental Oil Shale in Logan Wash, CO: 3 ug/cu m= indoor air, 0.6 ug/cu m= outdoor air near the facility(1). Air above shale oil wastewater held in closed containers contained C3 alkylphenol isomers (specific compounds not identified) at an average concentration of 1.9 ug per ml of air above 1 ml of wastewater. The wastewater was collected from Occidental Shale Oil in Logan Wash, CO during Dec 1982(1).

Contact allergy to phenol formaldehyde resins was studied in Sweden. A p-tert-butylphenol/formaldehyde resin (resin 3) and another phenol formaldehyde resin called resin 1 were used in patch tests on 1220 patients over the course of a year. The last 440 patients were also tested with a second phenol formaldehyde resin, designated resin 2. Patients reacting to at least one of the resins were also patch tested with 2-methylphenol, 4-methylol-phenol, 2,4,6-trimethylphenol, formaldehyde, phenol, and p-tert-butylphenol. ... Three patients reacted to 4-methylol-phenol and two reacted to all three methylol phenols. All of these patients had positive reactions to resin 3. Most patients positive to resin 1 were negative to methylol phenols.

ANAEROBIC DEGRADATION OF PHENOLIC COMPOUNDS TO METHANE AND CARBON DIOXIDE IN SEWAGE SLUDGE DIGESTION OCCURRED IN BOTH GROUND WATER AND LABORATORY DIGESTORS. WATER SAMPLES WERE COLLECTED FROM THE NEAR-SURFACE GROUND WATER IN AN AREA CONTAMINATED WITH PLANT PROCESS WASTES RESULTING FROM OPERATION OF A COAL TAR DISTILLING AND WOOD TREATING PLANT. PHENOLIC COMPOUNDS (INCLUDING 2,4,6-TRIMETHYLPHENOL) WERE ISOLATED FROM THE AQUEOUS SAMPLES BY DICHLOROMETHANE EXTRACTION.

2,4,6-Trimethylphenol is expected to biodegrade slowly in soils(SRC) based on a theoretical BOD of 7 percent using the Japanese MITI test during a 4 week incubation period(1). 2,4,6-Trimethylphenol was not biodegraded in an aerobic biofilm reactor over an unspecified incubation period(2). 2,4,6-Trimethylphenol, at an initial concn of 0.09 mg/l, underwent no degradation when incubated in coal tar-contaminated groundwater in an anaerobic digester for 8 weeks(3).

BCF values of 6-10 were measured in carp exposed to 0.2 mg/l of 2,4,6-trimethylphenol over 6 weeks and BCF values of 3-8 were measured for carp exposed to 0.02 mg/l for 6 weeks(1). According to a classification scheme(2), these BCF values suggest that the potential for bioconcentration in aquatic organisms is low(SRC).

The Henry's Law constant for 2,4,6-trimethylphenol is estimated as 3.1X10-6 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 0.05 mm Hg(1), and water solubility, 1,010 mg/l(2). This Henry's Law constant indicates that 2,4,6-trimethylphenol is expected to volatilize from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as approximately 14 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 104 days(SRC). 2,4,6-Trimethylphenol's estimated Henry' Law constant(1,2) indicates that volatilization from moist soil surfaces may occur(SRC). 2,4,6-Trimethylphenol is not expected to volatilize from dry soil surfaces(SRC) based upon the vapor pressure of this compound(1).

THE RELATIVE ABILITIES OF SUBSTITUTED PHENOLS TO INDUCE DRUG-METABOLIZING ENZYMES IN RAT LIVER WERE MEASURED. 24 HOURS AFTER A SINGLE INTRAGASTRIC DOSE, THERE WAS A CLOSE RELATION BETWEEN THE INDUCTION OF DRUG METABOLIZING ENZYMES AND THE LIPID-WATER PARTITION COEFFICIENTS OF THE TEST COMPOUNDS. WHEN ADMINISTERED AT 1.5 MILLIMOLES/KG/DAY FOR 6 DAYS, 2,4,6-TRIMETHYLPHENOL WAS A WEAK INDUCER OF ENZYME ACTIVITY.

SIXTY-THREE PHENOLIC COMPOUNDS WERE EXAMINED FOR THEIR ABILITY TO INHIBIT SHEEP VESICULAR GLAND PROSTAGLANDIN CYCLOOXYGENASE. EXAMINATION OF STRUCTURE-ACTIVITY RELATIONSHIPS INDICATED THAT INHIBITION WAS INCREASED BY RING SUBSTITUENTS WHICH WERE ELECTRON DONATING AND BY SUBSTITUENTS WHICH WERE HYDROPHOBIC. THE I-50 VALUE FOR 2,4,6-TRIMETHYLPHENOL WAS 7.2 MICROMOLES. INHIBITION OF ARACHIDONATE-INDUCED PLATELET AGGREGATION WAS EXAMINED FOR THREE OF THE MORE POTENT INHIBITORS. 2,4,6-TRIMETHYLPHENOL WAS MORE POTENT THAN INDOMETHACIN WHEN ASSAYED USING A 2 MINUTE PREINCUBATION OF INHIBITOR WITH PLATELETS.

VARIOUS ALKYLPHENOLS WERE EXAMINED FOR THE ABILITY TO CAUSE INCREASED WET AND DRY LUNG WEIGHTS IN MICE AFTER A SINGLE INTRAPERITONEAL INJECTION. 2,4,6-TRIMETHYLPHENOL CAUSED SIGNIFICANT DECREASES IN BODY WEIGHT, BUT FAILED TO CAUSE CONCOMITANT INCREASES IN LUNG WEIGHT.

THE CILIOTOXICITY OF INDIVIDUAL COMPOUNDS (INCLUDING 2,4,6-TRIMETHYLPHENOL) REPRESENTATIVE OF THE GASEOUS AND SEMIVOLATILE PHASES OF TOBACCO SMOKE WAS INVESTIGATED USING CHICKEN TRACHEAL ORGAN CULTURES. THE ALKYLATED PHENOLS EXHIBITED GREATER CILIOSTATIC EFFECTS THAN PHENOL ITSELF.

The rate constant for the vapor-phase reaction of 2,4,6-trimethylphenol with photochemically-produced hydroxyl radicals has been estimated as 2.4X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 16 hours at an atmospheric concn of 5X10+5 hydroxyl radicals per cu cm(1). 2,4,6-Trimethylphenol is not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(2). Based on experimental data, the photooxidation half-life of 2,4,6-trimethylphenol in mid-latitude surface waters during mid-summer was estimated to be 4.3 hours at water surfaces and 11 hours at a depth of 1 m(3). The photooxidation half-lives of 2,4,6-trimethylphenol in surface waters from Oregon and California were measured as 1.7-3.6 hours, while the half-lives in sub-surface waters were measured as 3.6-6 hours(4).