Registration Dossier

Environmental fate & pathways

Endpoint summary

Currently viewing:

Administrative data

Description of key information

Stability

The hydrolysis of tert-butyl peroxyisobutyrate in different aqueous buffer solutions (pH = 4, 7 and 9) at 15, 37 and 50 °C was investigated using HPLC-UV. Measurements revealed a fast hydrolysis of tert-butyl peroxyisobutyrate.

 

Biodegradation

Under the experimental conditions, the test substance is considered to be inherently biodegradable with a biodegradation of 28 %.

 

Bioaccumulation

The performance of a test for bioaccumulation in aquatic species, preferably fish, is scientifically unjustified.

 

Transport and distribution

The performance of adsorption/desorption screening tests is scientifically unjustified.

Additional information

Stability

The hydrolysis of tert-butyl peroxyisobutyrate in different aqueous buffer solutions (pH = 4, 7 and 9) at 15, 37 and 50 °C was investigated using HPLC-UV. Measurements revealed a fast hydrolysis of tert-butyl peroxyisobutyrate. On the basis of retention times both potential hydrolysis products (tert-butyl hydroperoxide and isobutyric acid) were identified in stored buffer solutions at pH = 7 and pH = 9.

Biodegradation

Under the experimental conditions, the test substance is non readily biodegradable in the 28-day modified Sturm test. Since biodegradation of the test substance totalled 28% at the end of the test, the test substance is considered to be inherently biodegradable.

Bioaccumulation

The performance of a test for bioaccumulation in aquatic species, preferably fish, is scientifically unjustified.

REACH Regulation (EC) No 1907/2006, Annex IX, Sect. 9.3.2, Col. 2, states as follows:

“9.3.2 The study need not be conducted if:

- the substance has a low potential for bioaccumulation (for instance a log Kow <= 3) and/or a low potential to cross biological membranes, or

- direct and indirect exposure of the aquatic environment is unlikely. ”

Direct and indirect exposure of the test item to water is highly unlikely. Due to the unstable nature of organic peroxides, it can be assumed that upon contact with water and organic matter, the test item undergoes rapid degradation resulting in the formation of respective alcohols and acids. In addition the low octanol-water partition coefficient (log Kow) of the test item (log Kow=2.68) indicates a low potential for bioaccumulation. Therefore, the test substance was considered to have no bioaccumulation potential.

Transport and distribution

The performance of adsorption/desorption screening tests is scientifically unjustified.

REACH Regulation (EC) No 1907/2006, Annex VIII, Sect. 9.3.1., Col. 2, states as follows:

“9.3.1: The study does not need to be conducted if:

– based on the physicochemical properties the substance can be expected to have a low potential for adsorption (e.g. the substance has a low octanol water partition coefficient); or

– the substance and its relevant degradation products decompose rapidly."

Due to the unstable nature of organic peroxides, it can be assumed that upon contact with water and organic matter, the test item undergoes rapid degradation resulting in the formation of respective alcohols and acids. In addition the low octanol-water partition coefficient (log Kow) of the test item (log Kow=2.68) indicates a low potential for adsorption. Therefore simulation adsorption/desorption screening tests were considered not scientifically justified.