Registration Dossier

Environmental fate & pathways

Phototransformation in air

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Hexahydrophthalic acid (HHPAc)
Half-life for reaction with photochemically-produced hydroxyl radicals: estimated to be between 11.6 and 34.7 hours, at different test conditions.
Overall degradation rate constant with OH radicals= 9.55E-07 cm3/(molecule-day).
Cyclohexane-1,2-dicarboxylic anhydride (HHPA)
Half-life for reaction with photochemically-produced hydroxyl radicals: estimated to be between 18.8 and 56.5 hours, at different test conditions.
Overall degradation rate constant with OH radicals= 5.89E-07 cm3/(molecule-day).

Key value for chemical safety assessment

Half-life in air:
56.5 h
Degradation rate constant with OH radicals:
0 cm³ molecule-1 d-1

Additional information

The stability of the substances in the atmosphere was calculated using the software AOPWIN (v1.92). It is predicted that both anhydride and acid forms will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals, with a half-life between 11.6 and 56.5 hours, and overall degradation rate constants with OH radicals between 5.89E-07 and 9.55E-07 cm3/(molecule-day), at different test conditions.

The most conservative values were selected.