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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Endpoint summary

Administrative data

Description of key information

Dicumyl peroxide is not readily biodegradable.

In a pelagic freshwater simulation study, the primary degradation half-life of dicumyl peroxide (bis(α,α-dimethylbenzyl) peroxide) is estimated at DT50 = 142 d, based on (poorly fitting) single first-order kinetics.

Mineralisation reaches a maximum of 12.9 % after 90 days (at 50 µg/L).

Additional information

Several studies are available investigating the potential of dicumyl peroxide for ready biodegradability. The most recent and reliable study, following OECD guideline 301F (manometric respirometry test) identified mineralisation rates after 28 days of, on average, 20 % at a test substance concentration of 100 mg/L, and of 44 % at 20 mg/L, however with high variability. Accordingly, although dicumyl peroxide fails the criterion for being regarded as “readily biodegradable” the test result shows that the substance is susceptible to mineralisation by biological processes.

In a previous study according to OECD guideline 301 D (closed-bottle test) dicumyl peroxide was not biodegradable after 28 days, but biodegradation was observed in a prolonged test for up to 57 days. This study is considered to be of limited reliability since employing an unsuitably high nominal test concentration (1000 mg/L) and lacking a toxicity control. Nevertheless, also this somewhat deficient study confirms the potential of dicumyl peroxide for biological degradability.

In a pelagic freshwater simulation study, the primary degradation half-life of dicumyl peroxide (bis(α,α-dimethylbenzyl) peroxide) is estimated at DT50 = 142 d, based on (poorly fitting) single first-order kinetics.

Mineralisation reaches a maximum of 12.9 % after 90 days (at 50 µg/L).

Testing on ultimate degradation in sediment is not considered to be required.

Likewise, simulation testing of degradation in soil is not considered to be required, since exposure of soil is expected to be negligible based on the chemical safety assessment.