Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Endpoint summary

Administrative data

Description of key information

Additional information

On the basis of the AOPWIN v1.92 calculation, which is based on the structural analogue of Blankophor TP 0306, CAS 16470 -24 -9, it is assumed that the test substance is indirectly photodegradable by reacting with hydroxyl radicals in the atmosphere with half-lives ranging from 1.56 hours (trans-isomer) to 1.61 hours (cis-isomer) taking into account a 24-h day and a mean OH radical concentration of 0.5E06 radicals per cm³ (Bieberstein, 2013).

For hydrolysis one study is available for the structural surrogate CAS 16470 -24 -9. In this study, which was conducted by Ciba-Geigy (1992), the stability of the tested substance could be demonstrated (hydrolysis < 10%) at pH 4, 7 and 9 at 50°C. The half-life of CAS 16470 -24 -9 is determined to be greater than 1 year.

In dilute solutions and in presence of sunlight,the structural analogue of Blankophor, CAS 16470 -24 -9, undergoes reversible isomerization of the stilbene moiety. In this process, two isomeric forms occur. The E- and Z-isomers are under environmental conditions in equilibrium within a few minutes. The parent substances used as fluorescent whitening agent consist of the E-isomer, while isomerization to the Z-form leads to complete loss of fluorescence. The study on CAS 16470 -24 -9 demonstrates that at solar latitude 60°, at 25°C, and on surface layer depths of 0 to 5 m the remaining E-isomer fraction is 17.8 to 13.3, respectively. The preceeding isomer equilibrium influences the photo-degradation rate. The half-life for photo-oxidation in natural water (Lake Greifensee) was measured for the same substance and under the same light conditions on the surface layer: 313 min (CAS 16470-24-9). The experimental kinetic data are used to calculate photochemical half-lives as a function of surface layer depth, optical density of the water, and time of the year.

As for CAS 16470 -24 -9, for Blankophor TP 0306 photodegradation in surface water is expected as well.