3,5,5-Trimethylhexanal

Protective Equipment for Firefighting: Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes.

For small (incipient) fires, use extinguishing media such as "alcohol" foam, dry chemical, or carbon dioxide. For large fires, apply water from as far as possible. Use very large quantities (flooding) of water applied as a mist or spray; solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Contact a licensed professional waste disposal service to dispose of this material. This combustible material may be burned in a chemical incinerator equipped with an afterburner and scrubber. Observe all federal, state, and local environmental regulations.

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.

Keep away from sources of ignition - no smoking.

Do not breathe vapor. Avoid contact with eyes, skin, and clothing. Avoid prolonged or repeated exposure.

If inhaled, remove to fresh air. If not breathing give artificial respiration. If breathing is difficult, give oxygen.

For more Preventive Measures (Complete) data for 3,5,5-TRIMETHYLHEXANAL (7 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 62(SRC), determined from a structure estimation method(2), indicates that 3,5,5-trimethylhexanal is expected to have high mobility in soil(SRC). Volatilization of 3,5,5-trimethylhexanal from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.9X10-4 atm-cu m/mole(SRC), using a fragment constant estimation method(3). 3,5,5-Trimethylhexanal is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 0.08 mm Hg(SRC), determined from a fragment constant method(4). Biodegradation data were not available(SRC, 2008).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 62(SRC), determined from a structure estimation method(2), indicates that 3,5,5-trimethylhexanal is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 4.9X10-4 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 4 hours and 5 days, respectively(SRC). According to a classification scheme(6), an estimated BCF of 47(SRC), from an estimated log Kow of 3.09(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is moderate(SRC). Biodegradation data were not available(SRC, 2008).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 3,5,5-trimethylhexanal, which has an estimated vapor pressure of 0.08 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 3,5,5-trimethylhexanal 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 12 hours(SRC), calculated from its rate constant of 3.3X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 3,5,5-Trimethylhexanal does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of 3,5,5-trimethylhexanal can be estimated to be 62(SRC). According to a classification scheme(2), this estimated Koc value suggests that 3,5,5-trimethylhexanal is expected to have high mobility in soil.

3,5,5-Trimethylhexanal's presence in isononanal (an isomeric mixture containing about 95% 3,5,5-trimethylhexanal and which is used in the perfume industry(1)) may result in 3,5,5-trimethylhexanal release to the environment through various waste streams(SRC).

An estimated BCF of 47 was calculated in fish for 3,5,5-trimethylhexanal(SRC), using an estimated log Kow of 3.09(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is moderate(SRC).

The Henry's Law constant for 3,5,5-trimethylhexanal is estimated as 4.9X10-4 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that 3,5,5-trimethylhexanal is expected to volatilize from water surfaces(2). 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)(2) is estimated as 4 hours(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 5 days(SRC). 3,5,5-Trimethylhexanal's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). 3,5,5-Trimethylhexanal is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 0.08 mm Hg(SRC), determined from a fragment constant method(3).

/LABORATORY ANIMALS: Acute Exposure/ When applied to the skin of rabbit at 500 mg for 24 hrs, moderate irritation effect observed.

/LABORATORY ANIMALS: Acute Exposure/ Isononylaldehyde was irritating to New Zealand rabbit skin in a 4-hr semi-occlusive patch-test and slightly irritating to rabbit eyes when rinsed off after 24 hr application. /Mixture of nonylaldehyde with about 90% 3,5,5-trimethylhexanal/

The rate constant for the vapor-phase reaction of 3,5,5-trimethylhexanal with photochemically-produced hydroxyl radicals has been estimated as 3.3X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 12 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 3,5,5-Trimethylhexanal is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). 3,5,5-Trimethylhexanal does not contain chromophores that absorb at wavelengths >290 nm(2) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

Occupational exposure to 3,5,5-trimethylhexanal may occur through inhalation and dermal contact with this compound at workplaces where 3,5,5-trimethylhexanal is produced or used. Use data indicate that the general population may be exposed to 3,5,5-trimethylhexanal via inhalation and dermal contact with consumer products containing 3,5,5-trimethylhexanal. (SRC)

3,5,5-Trimethylhexanal's presence in isononanal (an isomeric mixture containing about 95% 3,5,5-trimethylhexanal and which is used in the perfume industry) may result in 3,5,5-trimethylhexanal release to the environment through various waste streams. If released to air, an estimated vapor pressure of 0.08 mm Hg at 25 °C indicates 3,5,5-trimethylhexanal will exist solely as a vapor in the atmosphere. Vapor-phase 3,5,5-trimethylhexanal will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 12 hours. 3,5,5-Trimethylhexanal does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, 3,5,5-trimethylhexanal is expected to have high mobility based upon an estimated Koc of 62. Volatilization from moist soil surfaces is expected to be an important fate process based upon an estimated Henry's Law constant of 4.9X10-4 atm-cu m/mole. 3,5,5-Trimethylhexanal may not volatilize from dry soil surfaces based upon its vapor pressure. Biodegradation data were not available. If released into water, 3,5,5-trimethylhexanal is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces is expected to be an important fate process based upon this compound's estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 4 hours and 5 days, respectively. An estimated BCF of 47 suggests the potential for bioconcentration in aquatic organisms is moderate. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. Occupational exposure to 3,5,5-trimethylhexanal may occur through inhalation and dermal contact with this compound at workplaces where 3,5,5-trimethylhexanal is produced or used. Use data indicate that the general population may be exposed to 3,5,5-trimethylhexanal via inhalation and dermal contact with consumer products containing 3,5,5-trimethylhexanal. (SRC)

LD50 Rat oral 3240 mg/kg

LD50 Rat (Sprague-Dawley) oral 5266 mg/kg /Vehicle: ethanol and PEG200 1:1/

LD50 Rabbit dermal > 2500 mg/kg