2,6-Xylenol

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with 60-70% ethanol and transfer the dampened material to a suitable container. Use absorbent paper dampened with 60-70% ethanol to pick up any remaining material. Seal the absorbent paper, and any of your clothes, which may be contaminated, in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with 60-70% ethanol followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

Chemical Treatability of 2,6-Dimethylphenol; Concentration Process: Biological treatment; Chemical Classification: Phenols; Scale of Study: Unknown; Type of Wastewater Used: Pure compound (one solute in a solvent); Results of Study: 94.3% reduction based on chemical oxygen demand; rate of biodegradation 9 mg chemical oxygen demand/g hr (Activated sludge process).

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

6.0 [mg/m3]

26 [mg/m3]

59 [mg/m3]

MINIMUM PROTECTIVE CLOTHING: If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves.

Some data suggesting breakthrough times /for butyl rubber/ of approximately an hour or more. /Aromatic hydroxyl cmpd/

Breakthrough times /for neoprene/ greater than one hour reported by (normally) two or more testers. /Aromatic hydroxyl cmpd/

Breakthrough times /for polyvinyl alcohol/ less (usually significantly less) than one hour reported by (normally) two or more testers. /Aromatic hydroxyl cmpd/

LC50 PIMEPHALES PROMELAS (FATHEAD MINNOW) > 27 MG/L/96 HR /FRESHWATER, FLOW THROUGH BIOASSAY/

LC100 Terahymena pyriformis (ciliate) 2.66 mmole/l/24 hr /Conditions of bioassay not specified/

LC50 Daphnia magna (cladoceran) 11.2 mg/1/48 hr /Static bioassay/

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 460(SRC), determined from a log Kow of 2.36(2) and a regression-derived equation(3), indicates that 2,6-dimethylphenol is expected to have moderate mobility in soil(SRC). Volatilization of 2,6-dimethylphenol from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 6.7X10-6 atm-cu m/mole (4). 2,6-Dimethylphenol is not expected to volatilize from dry soil surfaces(3) based upon a vapor pressure of 0.274 mm Hg at 25 °C(4). The rate of biodegradation obtained for 2,6-dimethylphenol in a screening test with an adapted activated sludge seed was 94.3% chemical oxygen demand after 5 days(6). Other dimethylphenols have been reported to degrade within 4 to 14 days from soil(7).

AQUATIC FATE: Based on a classification scheme(1), a Koc value of 460(SRC), determined from a log Kow of 2.36(2) and a regression-derived equation(3), indicates that 2,6-dimethylphenol is expected to adsorb very little to suspended solids and sediment in water(SRC). 2,6-Dimethylphenol is expected to volatilize from water surfaces(3,SRC) based upon a Henry's Law constant of 6.7X10-6 atm-cu m/mole(4). Estimated volatilization half-lives for a model river and model lake are 6 days and 49 days, respectively(3,SRC). According to a classification scheme(5), an estimated BCF of 37(3,SRC), from 2,6-dimethylphenol's log Kow(2), suggests bioconcentration in aquatic organisms is moderate(SRC). In humic waters, degradation by the reaction with peroxy radicals should ensue with a half-life on the order of hours(6). 2,6-Dimethylphenol is not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(3). Screening studies indicate that a loss of 94.3% chemical oxygen demand was obtained after 5 days(7). In addition, it has been reported that 2,6-dimethylphenol was readily degraded in St. Lawrence River water(8). Biodegradation under anaerobic conditions failed to occur in one study, time unspecified(9) and only 7% degradation occurred after 8 weeks in another study(10).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2,6-dimethylphenol, which has a vapor pressure of 0.274 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 2,6-dimethylphenol 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 5.8 hours(SRC) from its rate constant of 6.60X10-11 cu cm/molecule-sec at 25 °C(3). Atmospheric 2,6-dimethylphenol is known to be removed by rainwater(4). 2,6-Dimethylphenol has an absorption band at 268 nm (water), and a shoulder may extend over 290 nm, thus making it a candidate for direct photochemical degradation(5,6). Night-time degradation in urban areas should occur rapidly through reaction with atmospheric nitrate radicals, as rate constants for this reaction with phenolic compounds are approximately 250 times faster than with hydroxyl radicals(7,SRC).

Waste water from the gasification of Indian Head lignite coal in North Dakota was determined to have an estimated 2,6-dimethylphenol concn of 12 mg/l(1). 2,6-Dimethylphenol was detected in three samples of shale oil wastewater in the range 0.75-1.7 ug/ml at three different sites at the Rio Blanco Oil Shale Company in Logan, WA and at the Laramie Energy Technology Center, WY(2). 2,6-Dimethylphenol was identified but not quantified in leachate collected from a Swedish municipal landfill in May 1990(3). 2,6-Dimethylphenol was identified as a volatile component from textile floor coverings, concn unknown(4).

2,6-Dimethylphenol

Hepatic

6 x 10 ^-4 mg/kg-day

The Koc of 2,6-dimethylphenol is estimated as 460(SRC), using a log Kow of 2.36(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that 2,6-dimethylphenol is expected to have moderate mobility in soil(SRC). 72.8% and 8% of 2,6-dimethylphenol was adsorbed onto the high clay content, adsorption activated materials Bentone 24 (pH 7.9) and Bentone 18C (pH 7.6), respectively; these values fluctuate as a function of pH(4).

Fine textured soils with appreciable iron oxides (e.g., Molokai clay) are more likely to slow the migration of 2.6-dimethylphenol than clay soils low in iron oxides (e.g, Fanno clay)(1). One study determined that adsorption of dimethylphenols by soils is very time dependent; the percentage of iron oxides and pH were determined to be two of the most important soil properties controlling the adsorption of 2,6-dimethylphenol by mineral soils(2). Laboratory gas-phase sorption/desorption studies for 2,6-dimethylphenol showed that sorption to high clay content soils in the gas phase can be important; the ratio of sorption to organic matter was the same for the two clays studied(2). It was shown that the adsorption and transformation of 2,6-dimethylphenol onto smectite clay surfaces were greatly influenced by the nature of the exchangeable cations Fe, Al, Ca, and Na(3).

URBAN/SUBURBAN: In 1984, a gas phase concn of 2,6-dimethylphenol was detected in 7 of seven rain events in Portland, OR, at concns ranging from 0.009-0.15 ng/cu m; the amount associated with adsorption to particulate matter was <5% of the gas phase concn in every case(1). 2,6-Dimethylphenol was detected at 0.4 ug/cu m in the air outside an oil shale wastewater facility in Logan WA, but not in a nearby undeveloped site(2).

TOXIC BY INGESTION AND SKIN ABSORPTION. /COMMERCIAL MIXTURES/

A case of fatal xylenol ingestion by a long stay mental hospital patient is described. The clinical course was similar to that observed in other phenolic poisonings with active bowel sounds, nausea ad vomiting, severe metabolic acidosis, hypotension and cardiac and renal failure. The formulation of xylenol ingested contains alcohol which would facilitate absorption; due to the dangers of such poisonings care must be exercised as to access and exposure to xylenol sterilising agents.

/SRP/: DIMETHYLPHENOLS OCCUR IN SHALE OIL PROCESS WATER, INDUSTRIAL WASTE WATER, AIRBORNE PARTICULATES, ... AND EVOLUTES FROM WASTE CHEMICAL DUMPS. /DIMETHYLPHENOLS/

2,6-Dimethylphenol's use for the preparation of coal tar disinfectants (1), in the manufacture of artificial resins(1,3), as a constituent of coal tar creosote (0.5 wt%)(2), as a raw material for pesticide manufacture(3), and as a component of automobile and diesel exhaust(4-7) may result in its release to the environment through various waste streams(SRC). In addition, 2,6-dimethylphenol has been released to the atmosphere by the paint industry(7) and via the combustion of phenolic resins and foam insulation used in the construction industry(8). Dimethylphenols, of which 2,6-dimethylphenol is an isomer, are components of disinfectants, solvents, pharmaceuticals, insecticides, fungicides, plasticizers, rubber chemicals, additives to lubricants and gasolines, wetting agents and dyestuffs(9).