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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Phototransformation in air

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Administrative data

Link to relevant study record(s)

Description of key information

The estimated second-order rate constant for reaction with photochemically-generated hydroxyl radical is 17.5E-12 cm3/molecule*sec at 25 degrees C.

Key value for chemical safety assessment

Half-life in air:
22 h

Additional information

The atmospheric fate of the 2,6-diemethylheptan-4-one substance was estimated using the U.S. EPA AOPWIN (v1.92a) software. An atmospheric half-life of 22 hrs (0.9 days) was estimated, based on predicted second-order reaction rate constant with photochemically-generated hydroxyl radical. This prediction was based on an ambient hydroxyl radical concentration of 500,000 molecules/cm3 and 24 hr photoday. Predictive accuracy of the software was evaluated by comparing measured and predicted rate constants for three analog substances: 2 -butanone; 3 -pentanone; and 3 -hexanone. Predicted values agreed within a factor of 1.3 of the experimental values, thereby validating the prediction for 2,6-diemethylheptan-4-one. Based on this estimation, the substance is not regarded as persistent in the atmosphere (i.e., half-life < 2 days).