Registration Dossier

Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The half-life of t-butylphenyldiphenyl phosphate (tBuPDPP) in a river die-away test was 1 day at 50 and 500 ppb levels. 

Key value for chemical safety assessment

Half-life in freshwater:
1 d
at the temperature of:
24 °C

Additional information

Information on the read-across Santicizer 154 is available. As the main component is the same for S-154 and the substance of concern (reaction mass of tert-butylphenyl diphenyl phosphate and di-tert-butylphenyl phenyl phosphate) the information on S-154 is relevant for this substance as well. Additionally, as the reaction mass of tert-butylphenyl diphenyl phosphate and di-tert-butylphenyl phenyl phosphate (substance covered in this registration dossier) is readily biodegradable, further simulation testing in water and sediment is not deemed necessary.

A river die-away study involved exposure of Santicizer 154 (S-154) to Mississippi River water in sealed bottles. The die-away or decrease in concentration of the test chemical was monitored as a function of time by sacrifice and analysis of selected bottle contents. Rapid biotransformation rates were observed for the S-154 major components, triphenyl phosphate (TPP) and t-butylphenyldiphenyl phosphate (tBuPDPP), with half lives of <0.5 and 1 day respectively at 50 and 500 ppb levels. A constituent present at lower concentrations in the multi-constituent, di(t-butylphenyl) phenyl phosphate (di-t-BuBPPP) disappeared more slowly with a half life of 7 days. In autoclaved river water, the composite half life for all components was 29 days indicating that chemical transformation was not a significant route.