[1,3-phenylenebis(1-methylethylidene)]bis[tert-butyl] peroxide

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Endpoint:

bioaccumulation in aquatic species: fish

Data waiving:

other justification

Justification for data waiving:

other:

Description of key information

The in vitro rate of metabolism was determined for [1,3(or 1,4)- Phenylenebis(1-methylethylidene)] bis[tert-butyl] peroxide using thein vitrometabolism trout liver S9 assay (OECD Test Guideline 319B, adopted in June 2018).

This organic peroxide metabolized rapidly under biologically active conditions with a metabolic half- life of 67 minutes or 1.13 hours. This data was used to extrapolatein vivorate constants of metabolism or k_METof 0.184 day^-1or 0.475 day^-1using hepatic portal blood flow or hepatic portal and arterial blood flow, respectively. The use of these k_MET values in conjunction with the Gobas model dropped the calculated BCF from 45,294 kg day^-1(assuming no metabolism) to 536 or 209 kg day^-1. The impact of metabolism on [1,3(or 1,4)- Phenylenebis(1-methylethylidene)] bis[tert-butyl] peroxide drops the BCF to less than the action level of 2000 (Reach Criteria) and should not be considered to have significant bioaccumulation potential.

A bioacucmulation in fish study according to the OECD 305 Test Guideline using aqueous exposure will be performed on analog 25155 -25 -3 and submitted later based on ECHA decision number SEV-D-2114369067-43-01/F.

Key value for chemical safety assessment

BCF (aquatic species):

536 L/kg ww