Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

The 2,6-dimethylheptan-4-one substance has a low vapor pressure (227 Pa at 20 °C), and only moderate solubility in water. Therefore, emission of the substance to water or soil have high potential to volatilize to the atmosphere. In the atmosphere, the fate of this, and most organic substances, is dominated by reaction with photochemically-generated hydroxyl radical. The half-life for this indirect photolysis is extimated to be 22 hrs. Because the substance can absorb UV light at wavelenghts > 290 nm, the potential for direct photolysis also exists, but is expected to be of much lesser importance. The atmospheric half-life is close to the 24 hr. half-life criterion for identification of persistent atmospheric pollutants. Therefore, the substance may have potential for relatively long-range transport in the atmosphere.

This substance can be emitted directly to surface waters as a result of its manufacture and use, and indirectly emitted to water and soil by deposition of atmospheric emissions of the volatile substance. The substance has an octanol-water partition coefficient (log Kow) of 3.71, indicating some potential for bioaccumulation in aquatic organisms. However, actual bioaccumulation is expected to be low, due to the potential for rapid metabolism/excretion in these organisms. The organic carbon-normalized adsorption coefficient (log Koc) of 2.07 indicates that migration of the substance through soil will be only slightly retarded, and contamination of groundwater via emissions to surface soil is possible. However, as is the case for most aliphatic ketone substances, this substance is readily biodegradable, and is therefore not expected to persist in surface water, soil, or sediments; and is expected to be effectively removed during activated sludge sewage treatment. The substance does not posses structural/functional groups which are susceptible to hydrolysis, and while direct photolysis is possible based on ability to absorb UV light at > 290 nm, this also is not expected to be an important fate process. Biodegradation is expected to be the dominant process affecting the fate and lifetime of this substance in the environment; and will prevent the substance and its components from becoming persistent pollutants.