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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

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Administrative data

Link to relevant study record(s)

Description of key information

1) Supporting: phototransformation study in water with one of the main constituents of DAPD (R-898; CAS 15017-02-4), K1, GLP, according to USEPA guideline

Key value for chemical safety assessment

Half-life in water:
1.78 d

Additional information

There is one study available evaluating photodegradation potential of DAPD (McLaughlin, 2004). This test was performed on N,N'-bis(2 -methylphenyl)benzene-1,4 -diamine (R-898; 20 to 30% of DAPD) as a surrogate for the entire test material. The substance was radiolabeled with 14C, making accurate quantification of the degradation kinetics possible with HPLC/beta counting. The substance was tested in two aqueous buffers (pH 6 and 8) at a concentration of 0.1 mg/L. Samples were exposed to xenon arc illumination with a radiation distribution which is similar to natural sunlight (photoperiod 12/12 light/dark). The experimental half-lives determined were 2.5 and 4.7 days at pH 6 and 8 respectively. These were then adjusted to compensate for actual external environments (natural sunshine) resulting in estimated half -lives of 0.94 and 1.78 days at pH 6 and 8 respectively. The value at pH 8 was used for further assessment.