Methyl isobutyl ketone

CAS RN: 108-10-1

Exposure Summary

Methyl isobutyl ketone's production and use as a solvent for gums, resins, nitrocellulose, paints, varnishes, and lacquers, denaturant agent for rubbing alcohol, in the manufacture of methyl amyl alcohol and in dry-cleaning preparations may result in its release to the environment through various waste streams. Its use as an extracting agent for the production of antibiotics and for the removal of paraffins from mineral oil for the production of lubricating oils may also result in its release to the environment through various waste streams. Methyl isobutyl ketone has been reported found in camphor, elderberry, ginger and Chinese quince. If released to air, a vapor pressure of 19.9 mm Hg at 25 deg C indicates methyl isobutyl ketone will exist solely as a vapor in the atmosphere. Vapor-phase methyl isobutyl ketone 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 30 hours. Methyl isobutyl ketone absorbs UV at wavelengths >290 nm and, therefore, may be susceptible to direct photolysis by sunlight. If released to soil, methyl isobutyl ketone is expected to have high mobility based upon an estimated Koc of 70. Volatilization from moist soil surfaces is expected to be an important fate process based upon an estimated Henry's Law constant of 1.4X10-4 atm-cu m/mole. Methyl isobutyl ketone may volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the Japanese MITI test, 84% of the Theoretical BOD was reached in 2 weeks indicating that biodegradation is an important environmental fate process in soil and water. If released into water, methyl isobutyl ketone 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 9 hours and 6 days, respectively. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. 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 methyl isobutyl ketone may occur through inhalation and dermal contact with this compound at workplaces where methyl isobutyl ketone is produced or used. Monitoring data indicate that the general population may be exposed to methyl isobutyl ketone via inhalation of ambient air, ingestion of food, and dermal contact with consumer products containing methyl isobutyl ketone. (SRC)
Find more information on this substance at: PubChem, PubMed