2,2,4-Trimethylpentane

114.23

114.23

1696876

208-759-1

QAB8F5669O

0496

39117

1262

DTXSID7024370

MOBILE LIQUID|COLORLESS LIQUID

29011000

0

4.46

APHA: ≤10 Liquid

0.69194 g/cm³ @ Temp: 20 °C

-107.45 °C

99.238 °C

18 °F

1.400

H2O: INsoluble

Flammables area

41 mm Hg ( 21 °C)

3.9 (vs air)

Reference value Inhalation-Rat LC: 20000 mg/m3/2 hours

Inflammable in case of open flame, high temperature, oxidant; burning produces irritating smoke

1%(V)

ODOR OF GASOLINE

3.68e-12 cm3/molecule*sec

ANTIKNOCK OCTANE NUMBER 100; DIPOLE MOMENT: 0

Highly flammable. Insoluble in water.

Hydrocarbons, Aliphatic Saturated

Highly Flammable

Saturated aliphatic hydrocarbons, such as ISOOCTANE, may be incompatible with strong oxidizing agents like nitric acid. Charring of the hydrocarbon may occur followed by ignition of unreacted hydrocarbon and other nearby combustibles. In other settings, aliphatic saturated hydrocarbons are mostly unreactive. They are not affected by aqueous solutions of acids, alkalis, most oxidizing agents, and most reducing agents.

784 °F (418 °C)|417 °C

LOWER FLAMMABLE LIMIT: 1.1% BY VOLUME, UPPER FLAMMABLE LIMIT: 6.0% BY VOLUME

The vapour is heavier than air and may travel along the ground; distant ignition possible. As a result of flow, agitation, etc., electrostatic charges can be generated.

II

3

UN 1262 3/PG 2

1

11-38-50/53-65-67

9-16-29-33-60-61-62

SA3320000

F,Xn,N

The warehouse is ventilated, low temperature and dry; stored separately from oxidants and acids

Explosive when mixed with air

Stable. Highly flammable. Incompatible with oxidizing agents, reducing agents.

P210-P261-P273-P301 + P310-P331-P501

H225-H304-H315-H336-H410

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. Substance may be transported hot. For hybrid vehicles, ERG Guide 147 (lithium ion batteries) or ERG Guide 138 (sodium batteries) should also be consulted. If molten aluminum is involved, refer to ERG Guide 169. (ERG, 2016)|Highly flammable. Vapour/air mixtures are explosive.|Flammable - 3rd degree

|Danger|H225 (100%): Highly Flammable liquid and vapor [Danger Flammable liquids]|P210, P233, P240, P241, P242, P243, P261, P264, P271, P273, P280, P301+P310, P302+P352, P303+P361+P353, P304+P340, P312, P321, P331, P332+P313, P362, P370+P378, P391, P403+P233, P403+P235, P405, and P501|Aggregated GHS information provided by 661 companies from 35 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.|H224 (100%): Extremely flammable liquid and vapor [Danger Flammable liquids]|P210, P233, P240, P241, P242, P243, P261, P264, P270, P271, P280, P301+P312, P302+P352, P303+P361+P353, P304+P340, P312, P321, P330, P332+P313, P362, P370+P378, P403+P233, P403+P235, P405, and P501|The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory.|H225: Highly Flammable liquid and vapor [Danger Flammable liquids]

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: CAUTION: All these products have a very low flash point: Use of water spray when fighting fire may be inefficient. CAUTION: For mixtures containing alcohol or polar solvent, alcohol-resistant foam may be more effective. SMALL FIRE: Dry chemical, CO2, water spray or regular foam. LARGE FIRE: Water spray, fog or regular foam. Do not use straight streams. Move containers from fire area if you can do it without risk. FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2016)|Use powder, AFFF, foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water. Combat fire from a sheltered position.

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet). FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material. LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2016)

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. (ERG, 2016)

Flammable, dangerous fire risk

EXPLOSIVE LIMITS IN AIR: 1.1-6%|Explosive limits , vol% in air: 1.1-6.0

/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a "P" may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water. Substances may be transported hot.|/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Health: Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.|/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Public Safety: CALL Emergency Response Telephone Number ... . As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering.|/GUIDE 128: FLAMMABLE LIQUIDS (NON-POLAR/WATER-IMMISCIBLE)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection.|For more DOT Emergency Guidelines (Complete) data for ISO-OCTANE (8 total), please visit the HSDB record page.

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./|The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.|The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Evacuate danger area! Personal protection: self-contained breathing apparatus. Remove all ignition sources. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.

Fireproof. Separated from strong oxidants. Cool. Keep in a well-ventilated room.

No indication can be given about the rate at which a harmful concentration of this substance in the air is reached on evaporation at 20 °C.

The substance is irritating to the eyes, skin and respiratory tract. The substance may cause effects on the kidneys, liver and nervous system. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis.

The substance defats the skin, which may cause dryness or cracking.

NO open flames, NO sparks and NO smoking. Closed system, ventilation, explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding). Do NOT use compressed air for filling, discharging, or handling.

Use ventilation, local exhaust or breathing protection.

Protective gloves.

Wear safety goggles.

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Iso-octane is included on this list.

| 0 - Materials that, under emergency conditions, would offer no hazard beyond that of ordinary combustible materials.| 3 - Liquids and solids that can be ignited under almost all ambient temperature conditions. Materials produce hazardous atmospheres with air under almost all ambient temperatures or, though unaffected by ambient temperatures, are readily ignited under almost all conditions.| 0 - Materials that in themselves are normally stable, even under fire conditions.

2,2,4-Trimethylpentane is released to the environment through the manufacture, use, and disposal of products associated with the petroleum and gasoline industry. During an accident, 2,2,4-trimethylpentane penetrated the skin of a human which caused necrosis of the skin and tissue in the hand and required surgery. No other information is available on the acute (short-term) effects in humans. Irritation of the lungs, edema, and hemorrhage have been reported in rodents acutely exposed by inhalation and injection. No information is available on the chronic (long-term), reproductive, developmental, or carcinogenic effects of 2,2,4-trimethylpentane in humans. Kidney and liver effects have been observed in rats chronically exposed via gavage (experimentally placing the chemical in the stomach) and inhalation. EPA has not classified 2,2,4-trimethylpentane with respect to potential carcinogenicity.

The average exhaust from 67 gasoline fueled vehicles driven through an Australian urban driving cycle on a chassis dynamometer contained 1% (w/w) iso-octane of the total non-methane hydrocarbon emitted(3). The average emission of iso-octane from 46 in-use emission-controlled U.S. passenger cars made between 1975-1982 was 2.4% of the total emission (both exhaust and evaporative) under federal test procedure (FTP) driving cycle(2). On the average, 0.25% of the total non-methane hydrocarbon emitted from a wood combustion stack was due to iso-octane(4). Iso-octane has been detected in emitted gases from waste and landfill sites(1,5).

URBAN/SUBURBAN: Iso-octane has been qualitatively detected in the ambient air of many cities around the world including air in Pullman, WA(4). Pretoria, South Africa(3), Johannesburg, South Africa(3), Durban, South Africa(3), Zurich, Switzerland(2) and Leningrad, USSR(1).|URBAN/SUBURBAN: The concentration range of iso-octane in Los Angeles air in 1981 was 3-15 ppb(1). The average and maximum concentration of this compound in Houston, TX air obtained from 679 sampling points were 6 and 101 ppbC, respectively in 1977(3). In Houston, TX, the level of iso-octane ranged from none detected to 416.3 ppbC in Sept. 1983 and 39.1 to 146.8 ppbC in Jan. 1984(2). The background concentration of iso-octane in Janesville, WI air in 1978 was <0.5 ug/cu m, but the concns in atmospheric plume at distances of 10, 15 and 40 miles above Janesville were 1.5, 2.5 and 2.0 ug/cu m, respectively(4). The concn level of iso-octane in Tulsa, OK air in 1978 ranged 2.1-8.5% of the total hydrocarbon, although its composition was 17.1% in the air over a petroleum refinery(5).|URBAN/SUBURBAN: The median and max concn of iso-octane in 39 U.S. cities during 1984-1986 were 6.8 and 106 ppbC(1). The ground level concn of iso-octane on a fall day in 1968 in the Los Angeles Basin was 1.1-10.2 ppb, while the concn 1,500 ft above ground was 18.9 ppb(2). The concn of the compound in urban plumes over Lake Michigan (in the vicinity of Chicago and Milwaukee) in 1976 was 6.8-10.0 ppb(3). The average concn over Tokyo, Japan in 1980 was 0.2 ppb(4).|SOURCE DOMINATED: The average concn of iso-octane inside Lincoln Tunnel was 56.6 ppbC in 1982 compared to 275.3 ppbC in 1970(1). This 5-fold decrease in concn was attributed to the use of catalyst-equipped vehicles(1). The amount of this compound detected along U.S. Highway 70 near Raleigh, NC amounted to 1.07-1.48% of the total non-methane hydrocarbon concn(3). The in-vehicle concn of iso-octane in two four-door sedans averaged 21.1 ug/cu m in urban, 12.0 ug/cu m in interstate and 2.4 ug/cu m in rural areas for these driving routes. The corresponding concns along the sidewalks were 3.8 ug/cu m 1.6 and 0.5 ug/cu m(2).|RURAL/REMOTE: The average concentration of iso-octane in two ground level air samples collected in an orange grove near Dunedin, FL in 1976 was 1.3 ppbC(1). The concn of the compound at Jones State Forest, 38 miles north of Houston, TX in 1978 ranged from 0.3 to 16.7 ppbC(2). The median iso-octane concn in four remote sites in Northwestern North Carolina in 1981-1982 was 0.2 ppbC(3). The compound constituted 0.5% of the total hydrocarbon composition in Smoky Mountain air in 1978(2).

Iso-octane was detected at a concentration 0.25 mg/l in water when 10 gms of sliced polyethylene pipes used for distribution of potable water was allowed to soak in a liter of mineral water for 48 hrs(1).

practically nontoxic

RABBITS WERE EXPOSED TO 2500 OR 5000 PPM CARBON MONOXIDE, WITH OR WITHOUT 5000 PPM OCTANE, OR ISO-OCTANE, OR TO AUTOMOBILE EXHAUST FUMES. THE HYDROCARBONS ENHANCED THE CARBON MONOXIDE INDUCED HYPOTENSION & BRADYCARDIA, BUT HASTENED THE RECOVERY FROM THE CARBON MONOXIDE INDUCED ELECTROCARDIOGRAPHIC MODIFICATIONS.

Iso-octane is naturally found in crude petroleum(1) and in small amounts in natural gas(2).

JP-4 (JET FUEL) SAMPLES CONTAIN HYDROCARBONS, INCLUDING ISO-OCTANE.|Since iso-octane is a constituent of petroleum and gasoline, it is released to the environment by the petroleum industries during refining processes and during the use of gasoline(2). Automotive exhaust and automotive evaporative emissions are most important sources of iso-octane in the atmosphere(1,4-7). Products, such as polyethylene pipes used for distribution of drinking water, can release this compound in water and the atmosphere(9). Hazardous wastes sites(3), landfills(3,8) and emissions from wood combustion(7) also release iso-octane into the environment.

TERRESTRIAL FATE: Photolysis and hydrolysis of iso-octane are not expected to important in soil(2,6). Although iso-octane may undergo slow biodegradation in soil(5), volatilization from dry and wet soil surfaces is expected to be more important fate process. The vapor pressure of 49.3 mm Hg(3) and a value of 3.01 atm cu-m/mole for Henry's Law constant(4) indicates high volatility from dry and moist soil surface. In subsurface soil, adsorption of iso-octane is expected to be important as indicated by average log Koc value of 4.35 in three sediments(1) and an estimated log Koc value of 3.43 in soil(2).|AQUATIC FATE: The hydrolysis of iso-octane in water is not expected to be important because the compound does not contain any hydrolyzable group(2). The photolysis of the compound in water is also expected to be unimportant because iso-octane is transparent to wavelengths available in sunlight(5). Although slow biodegradation may occur in aquatic medium(4), volatilization from water is expected to be the dominant process as indicated by the value 3.01 atm-cu m/mole for Henry's law constant(3). The average log Koc value of 4.35 in sediments(1) indicate that most of the compound may remain adsorbed to sediment and suspended solids in aquatic medium. A log bioconcentration factor of 2.57 estimated from a regression equation based on water solubility(2) indicates that bioconcentration in aquatic organisms may be important.|ATMOSPHERIC FATE: The rate constant for the reaction of iso-octane with atomic oxygen (3P) is 5.5X10+10 cu cm/mol-sec(3). Based on this rate constant and the concentration of atomic oxygen of 2.5X10+4 molecules/cu cm in a typical atmosphere(4), this reaction may not be important in the atmosphere. The gas-phase reactions of alkanes with ozone and nitrate radicals are of negligible importance as atmospheric loss processes(1). The rate constant for the reaction of iso-octane with OH radicals at 25 °C is given as 3.66-3.68X10-12 cu cm/molecule-sec(1,2). Based on an average 24-hr atmospheric OH radical concentration of 5X10+5 molecules/cu cm(5), the half-live of iso-octane due to this reaction is 4.4 days.

Alkanes do not contain any hydrolyzable group and are generally resistant to hydrolysis(1). Therefore, hydrolysis of iso-octane in water and soil is not expected to be important. The compound is transparent to tropospheric sunlight(2) indicating that direct photolysis in ambient water and soil may not be important. The rate constants for the gas phase reaction of iso-octane with oxygen atoms (3P) and hydroxyl radicals are 5.5X10+10 cu cm/mol-sec(5) and 3.66-3.68X10-12 cu cm/molecule-sec(3-4), respectively. Based on typical 24-hr average atmospheric atomic oxygen concentrations of 2.5X10+4 molecules/cu cm(6) and OH radical concentration of 5X10+5 radicals/cu cm(7), the reaction with atomic oxygen can be estimated to be unimportant and the half-life for reaction with OH radicals can be estimated to be 4.4 days.|The rate constant for the reaction of OH radicals with iso-octane in aqueous solution is 6.023X10+9/M-sec(1). If it is assumed that the concentration of OH radicals in a typical natural eutrophic water is 3X10-17 M(2), the half-life for the oxidation of iso-octane by photochemically produced OH radicals in water is expected to be 44 days(SRC).|Calculated half-life time in water at 25 °C and 1 m depth based on evaporation: 5.55 hr; evaporation rate: 0.124 m/hr.

Based upon a water solubility of 2.44 mg/L at 25 °C(1), the log bioconcentration factor for iso-octane has been estimated to be 2.57 from a regression equation(2). This value indicates bioconcentration may be important in aquatic organism(SRC).

The adsorption of several hydrocarbons including iso-octane in five types of soil was studied by measuring the retention volumes(1). Hydrocarbon retention by dry soils increased with molecular weight and unsaturation and decreased with branching. The retention volume of iso-octane was found to be high, but the authors did not provide any Koc values. The log Koc for iso-octane in soil has been estimated to be 3.43 from the water solubility of the compound(4) and a regression equation(2). The average log Koc for this compound in sediments from a salt marsh, a pond and a river was 4.35. Therefore, iso-octane is expected to generally remain strongly adsorbed to soil and sediments(5,SRC).

Based on water and vapor phase mass transfer coefficients, the volatilization half-life of iso-octane at 25 °C from a still body of water at a depth of 1 m was estimated to be 5.6 hrs(1). Using more realistic winding blowing conditions, the evaporation half-life of the compound from a model river 1 meter deep, flowing at 1 m/sec with a wind speed of 3 m/sec was estimated to be 3.1 hrs(2). However, neither estimation method considers the effect of adsorption on the rate of volatility. Using EXAMS model which considers various input parameters including the effect of adsorption, the volatilization half-life of iso-octane from a model pond has been estimated to be 15 days(3,SRC).

GROUNDWATER: Iso-octane was detected in one on-site and one off-site well water sample from a waste site of a non-lubricating automotive fluids production plant in Michigan at concentration of 0.005 mg/L and 0.008 mg/L, respectively(1).

Iso-octane has been detected in the volatile components of Chickpea (Cicer arietinum L)(1).

The most probable route of human expsoure to iso-octane is by inhalation as indicated by the monitoring data in the gasoline industry(1-3). The detection of the compound in the expired air of "normal" humans (not occupationally exposed)(4) indicates inhalation exposure to general population may be important(SRC).|The occupational exposures of truck drivers and terminal loading operators to gasoline vapors containing iso-octane were studied(1). The mean air concns of iso-octane for service station attendants, transport drivers and outside operators in petroleum industry were 0.670 mg/cu m, 1.495 mg/cu m and 0.824 4 mg/cu m, respectively(2). The concn of iso-octane in the personal air of a high volume service station attendant was 0.2 ppm(3).

Iso-octane was detected in the expired air of 29.7% of selected normal people not occupationally exposed to the compound(1). The geometric mean concentration of iso-octane in the expired air of this general population was 0.604 ng/l(1).

Respiration is the most likely route by which 2,2,4-trimethylpentane is absorbed. Although it has not been determined, the respiratory uptake of 2,2,4-trimethylpentane is probably similar to that seen for n-octane. Oral absorption of (14)C-2,2,4-trimethylpentane has been reported ... to occur to the extent of 86% in male rats based on recovery of radioactivity in urine, expired organics, and expired (14)C-carbon dioxide. Dermal bioavailability has not been reported, but absorption of 2,2,4-trimethylpentane through the skin would be expected to be minor based on percutaneous results reported for n-heptane and n-octane. Oral gavage studies ... in male rats with (14)C-2,2,4-trimethylpentane (0.5 mg/kg, single dose) revealed that the radioactivity is selectively distributed in the kidneys 72 hr after administration. It has been suggested that the renal retention of 2,2,4-trimethylpentane is related to the hydrocarbon-induced nephropathy observed specifically in male rats.|Metabolic disposition of 2,2,4-trimethylpentane was studied in male and female Fischer 334 rats. Rats were treated with a single oral dose of (14)C 2,2,4-trimethylpentane (4.4 mmol/kg; 2 microCi/mmol). Radiolabeled material in kidney, liver, and plasma was determined at 4, 8, 12, 24, and 48 hr after dosing. Maximum concentration of 2,2,4-trimethylpentane derived radioactivity in kidney, liver, and and plasma of male rats was found after 12 hr (1252, 1000, and 403 nmol eg/g, respectively), whereas those measured in females were found after 8 hr (557, 1163, and 317 nmol eq/g, respectively). A selective retention of the 2,2,4-trimethylpentane derived radiolabel in the kidneys of male rats was noted when peak tissue concentration was expressed as a percentage of administered dose. Kidney concentrations of 2,2,4-trimethylpentane derived radiolabel increased in a nonlinear, but dose dependent radiolabel increased in a nonlinear, but dose-dependent, manner; the kidney to plasma ratio was greater at low doses than at higher doses. Increased retention of radiolabel material in the kidney was associated with a significant increase in renal concentration of the male rat specific protein, alpha 2u-globulin, 24 and 48 hr after 2,2,4-trimethylpentane administration. Total radioactivity collected in urine 48 hr after 2,2,4-trimethylpentane administration was similar in males and females (32 and 31% of dose). Identification and quantitation of the urinary metabolites of 2,2,4-trimethylpentane showed that both male and female rats metabolize 2,2,4-trimethylpentane via the same pathway and at a similar rate. Female rats, however, excreted more conjugates of 2,4,4-trimethyl-2-pentanol in urine than males. 2,2,4-Trimethyl-2-pentanol was the major metabolite present in the male rat kidney, but was absent in the female rat kidney. The renal retention of 2,4,4-trimethyl-2-pentanol appears to account for the delayed clearance observed in the disposition of (14)C 2,2,4-trimethylpentane derived radiolabel. Based on the concomitant accumulations in renal alpha 2u-globulin concentration and renal 2,4,4-trimethyl-2-pentanol concentration, an association is speculated between these two components. The male rat specific accumulation of 2,4,4-trimethyl-2-pentanol may therefore reflect the accumulation of a metabolite-alpha 2u-globulin complex. This may be relevant to the male-rat-specific nephrotoxicity produced by 2,2,4-trimethyl-pentane.|A study was conducted to determine if the rate of uptake and route of excretion of inhaled hydrocarbons and their metabolites might be different for branched alkanes relative to straight chain isomers. Male F344/N rats were exposed by nose only inhalation to nominal concentrations of 1 or 350 ppm (14)C labeled octane and isooctane for a period of 2 hours. Urine and feces were collected as were exhalants at 3, 6, 9, 18, 24, 30, 42, 54, and 66 hr post exposure. Exhalants were also collected at 1 and 2 hr post exposure. Elimination was most exclusively via the kidneys for isooctane while octane was eliminated about equally in urine and as exhaled carbon dioxide. Isooctane was excreted through the kidneys over the entire 70 hr, whereas octane excretion was essentially completed after 10 to 20 hr. At 70 hr after exposure about 5% of the octane equivalents inhaled at 1 ppm remained in the carcass. The author suggests that the different patterns of metabolites excretion of isooctane compared to octane may be a factor affecting the differences in nephrotoxicity between these two compounds.

Metabolism of 2,2,4-trimethylpentane probably occurs by omega and omega-l oxidation to yield the corresponding alcohol and acid metabolites. While the exact structure of these remains to be elucidated, there is evidence that the cytochrome p450 system, lauric acid hydroxylases, and palmitoyl CoA oxidase in the liver and kidneys play a role in the biotransformation of 2,2,4-trimethylpentane. Studies indicate that 2,2,4-trimethylpentane (radiolabeled with (14)C) is metabolized by the cytochrome p450 system and that modulation of this enzyme system (with phenobarbital and metyrapone) will alter the disposition and renal retention of 2,2,4-trimethylpentane. Pretreatment of male rats with phenobarbital decreased the expired organics (from 40 to 10% of dose) and increased the urine radioactivity (from 46 to 80%), but did not alter the retention of radioactivity in the kidneys. Metyrapone (an inhibitor of cytochrome p450) increased the elimination half-life of expired 2,2,4-trimethylpentane (2.8 to 3.8 hr), did not alter urinary radioactivity, and decreased radioactivity retention in the kidney by 37%. From these studies, elimination of 2,2,4-trimethylpentane (isooctane) occurs mainly by metabolism to water-soluble products which are excreted in the urine and by exhalation of parent material.|Metabolic disposition of 2,2,4-trimethylpentane was studied in male and female rats. Rats were treated with a single oral dose of (14)C 2,2,4-trimethylpentane (4.4 mmol/kg; 2 uCi/mmol). Identification and quantitation of the urinary metabolites of 2,2,4-trimethylpentane showed that both male and female rats metabolize 2,2,4-tremethylpentane via the same pathway and at a similar rate. Female rats, however, excreted more conjugates of 2,4,4-trimethyl-2-pentanol in urine than males. 2,4,4-Trimethyl-2-pentanol was the major metabolite present in the male rat kidney, but was absent in the female rat kidney.|When (14)C 2,2,4-trimethylpentane was administered to an adult male Fischer-344 rat (300 mg/kg, ig) 22, 16, and 10 hr before sacrifice, 16% of the administered radioactivity was eliminated in the urine as 2,2,4-trimethylpentane metabolites.

40.00 Days

The mechanism by which 2,2,4-trimethylpentane related radiolabel was retained in the kidneys after dosing of Fischer 344 rats with 4.4 millimoles/kg radiolabeled 2,2,4-trimethylpentane was studied. The subcellular localization of radioactivity in the kidney was examined. The nature of the association of the parent compound or any metabolite with alpha2u-globulin in the kidney, liver, plasma and urine of male rats and in the kidney of female rats was investigated. More radiolabeled material was detected in the kidneys of male than female rats. Subcellular fractionation of male kidneys 24 hours after dosing with 2,2,4-trimethylpentane, by centrifugation at 116,000 times gravity, resulted in an association of 60% of the radiolebeled material with the supernatant. Two components were obtained from this supernatant by column chromatography. One component contained 26% of the radiolabel and coeluted with alpha2u-globulin and cross reacted with an antibody specific for this globulin. the other component, which the authors suggest contains 2,2,4-trimethylpentane metabolites, eluted in a low molecular weight range. Column chromatography analysis was performed of the male liver and female kidney 116,000 times gravity supernatants, and of male urine and plasma, 24 hr after administration of 2,2,4-trimethylpentane. Radiolabel from 2,2,4-trimethylpentane in male urine resolved into the same two components as the male kidney supernatant. Radiolabel in male liver and female kidney supernatants eluted as a single component with a low molecular weight. The metabolite bound to the male rat kidney fraction containing alpha2u-globulin was identified as 2,4,4-trimethyl-2-pentanol. The amount of this metabolite retained in the kidneys was maximal by 24 hr and then remained virtually constant for 72 hr.|Subchronic exposure of male rats to the nephrotoxin 2,2,4-trimethylpentane causes accumulation of protein droplets in the epithelial cells of the renal cortex. Experimental evidence suggests that these droplets contain alpha 2u-globulin, a low molecular weight protein found specifically in the urine of male rats. It has been proposed that aldehyde metabolites of 2,2,4-trimethylpentane form Schiff base adducts with the lysine groups of alpha 2u-globulin and thereby inhibit renal lysosomal processing of the protein. Accordingly, the ability of 2,2,4-trimethylpentane and its metabolites to covalently bind to alpha 2u-globulin was examined. As a model, a (14)C formaldehyde-alpha 2u-globulin Schiff base was formed. This protein adduct was stabilized by reduction with cyanoborohydride and could be identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Protein analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that hepatocytes isolated from male Fischer 344 rats produced significant quantities of alpha 2u-globulin in culture, whereas hepatocytes from female rats did not. A 15 hr exposure of metabolically competent, primary cultures of male rat hepatocytes to (14)C 2,2,4-trimethylpentane (0.1 and 0.5%, v/v), followed by reduction with cyanoborohydride, dialysis, and analysis with sodium dodecyl sulfate polyacrylamide gel eletrophoresis, revealed no evidence of radiolabeled alpha 2u-globulin. Analysis as above showed no 2,2,4-trimethylpentane derived radioactivity in fractions containing alpha 2u-globulin from liver, blood, kidney cortex, or urine. The absence of a detectable covalent interaction between 2,2,4-trimethylpentane and alpha 2u-globulin following in vitro or in vivo exposure suggests that 2,2,4-trimethylpentane alpha 2u-globulin adduct is not responsible for the excessive formation of protein droplets in the renal cortex of exposed male rats.

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution. (ERG, 2016)

Excerpt from ERG Guide 128 [Flammable Liquids (Water-Immiscible)]: Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Wash skin with soap and water. In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin. Keep victim calm and warm. (ERG, 2016)

Fresh air, rest. Artificial respiration may be needed. Refer for medical attention.

Remove contaminated clothes. Rinse and then wash skin with water and soap.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

A DESCRIPTION IS GIVEN OF A SERIOUS HAND INJURY WHICH RESULTED FROM THE UNPACKING OF SILICON DIOXIDE FILLED HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC COLUMN BY PUMPING ISOOCTANE THROUGH THE COLUMN. A MIXTURE OF SILICON DIOXIDE & ISOOCTANE WAS SUDDENLY DISCHARGED SO VIOLENTLY THAT SOME ISOOCTANE PENETRATED THE SKIN, CAUSING NECROSIS WHICH REQUIRED SURGERY.|The abilities of unleaded gasoline and 2,2,4-trimethylpentane which comprises about 10% of unleaded gasoline to induce gene locus mutation and sister chromatid exchange in a human lymphoblast system were investigated. TK6 human lymphoblastoid cells were used. The cytotoxic effects of medium saturated with these agents were first determined by monitoring cell growth following treatment. For cell exposures, a hydrocarbon saturated medium was mixed in different ratios with normal medium containing the cells. Exposures were for 3 hours. For unleaded gasoline, ratios were 1:7 or 1:3 (saturated/normal); for 2,2,4-trimethylpentane, 1:1 or no dilution concentrations were used. Incubations were performed with and without S9. Benzo(a)pyrene was used as a positive control and to test the bioactivating ability of S9 in the presence of the treatment agents. Unleaded gasoline in a 1:1 ratio dissolved TK6 cells. A reduction to 1:3 increased cell survival to approximately 70%. Greater than 60% of cells survived treatment in the 2,2,4-trimethylpentane saturated medium. Neither unleaded gasoline at its maximum tolerated concentration, nor 2,2,4-trimethylpentane at its limit of solubility, induced mutation at the thymidine kinase locus. Negative results were seen both in the presence and absence of the rat liver homogenate metabolizing system. Sister chromatid analyses were also negative for both agents. The expected frequency of mutation was observed with benzo(a)pyrene in the presence of the bioactivating system indicating that no inhibition of metabolism was taking place. The authors conclude that the carcinogenicity and nephrotoxicity of these agents observed in vivo do not correlate with any marked genotoxicity in vitro.

2,2,4-trimethylpentane

The substance can be absorbed into the body by inhalation and by ingestion.

Confusion. Dizziness. Headache. Nausea. Vomiting.

Dry skin. Redness. Pain.

Redness.

GRADES: ... PURE; RESEARCH; SPECTROPHOTOMETRIC.

All other chemical product and preparation manufacturing|Pentane, 2,2,4-trimethyl-: ACTIVE|The name isooctane has also been applied to 2-methylheptane.

Hazardous Air Pollutants (HAPs)|Fire Hazards -> Flammable - 3rd degree|Cosmetics -> Solvent