Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
no hazard identified

Marine water

Hazard assessment conclusion:
no hazard identified

STP

Hazard assessment conclusion:
PNEC STP
PNEC value:
100 mg/L
Assessment factor:
10

Sediment (freshwater)

Hazard assessment conclusion:
PNEC sediment (freshwater)
PNEC value:
8.9 mg/kg sediment dw
Assessment factor:
100
Extrapolation method:
assessment factor

Sediment (marine water)

Hazard assessment conclusion:
PNEC sediment (marine water)
PNEC value:
0.89 mg/kg sediment dw
Assessment factor:
1 000
Extrapolation method:
assessment factor

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
PNEC soil
PNEC value:
5.03 mg/kg soil dw
Extrapolation method:
equilibrium partitioning method

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
PNEC oral
PNEC value:
44.4 mg/kg food
Assessment factor:
90

Additional information

General discussion:

A full aquatic dataset is available; one key study, short-term as well as long-term, is available for each trophic level (some on analogous CAS 25155 -25 -3). To summarize no effect of [1,3-phenylenebis(1-methylethylidene)]bis[tert-butyl] peroxide was observed up to its water solubility limit (0.04 mg/L). As a consequence, there is no hazard identified for the aquatic compartment.

To be able to derive a PNEC for the soil compartment a PNEC for the aquatic compartment is derived and used in the Equilibrium Partitioning Method (EPM).

We propose to consider the water solubility limit as a NOEC value and use an assessment factor of 10 as a full aquatic dataset is available, to derive the PNEC aquatic. The PNEC aquatic to be used in the EPM is 0.004 mg/L.

Conclusion on classification

One key study is available for each acute- and chronic endpoint. To summarize no effect of [1,3-phenylenebis(1-methylethylidene)]bis[tert-butyl] peroxide was observed up to its water solubility limit (0.04 mg/l).

However, [1,3-phenylenebis(1-methylethylidene)]bis[tert-butyl] peroxide is not readily biodegradable (OECD 301D) and its log Kow was estimated at 7.3.

That is the reason why according to 67/548/ECC, [1,3-phenylenebis(1-methylethylidene)]bis[tert-butyl] peroxide is classified "Aquatic chronic category 4".