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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

The hydrolysis of tert-butylperoxyneodecanoate (TBPND) 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 TBPND (half-live: 0.9 hours) at pH = 4 and 50 °C. 

The test item was biodegradable 26 % at day 28 in the closed bottle test according to OECD guideline 301. In the prolonged closed bottle test this compound was biodegraded 53 % at day 140. Therefore it can be concluded that the test item is not ready biodegradable, but inherently biodegradable.

The performance of simulation tests for biodegradation in water and sediment is scientifically unjustified.

The performance of tests for biodegradation in soil is scientifically unjustified.

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

The Koc was mesured using HPLC method. This method is applicable for substances which have log Koc value ranging from 1.5 to 5.0. The adorption coefficient was estimated to be 4424 and the log Koc was 3.64.

Additional information

The hydrolysis of tert-butylperoxyneodecanoate (TBPND) 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 TBPND (half-live: 0.9 hours) at pH = 4 and 50 °C. The degradation products of the hydrolysis of tert-butylperoxyneodecanoate (TBPND) (7,7-dimethyloctanoic acid andtert-butanol) were identified qualitatively using HPLC-MS and GC-FID, respectively.

 

The ready biodegradability of the test item was assessed according to OECD guideline 301 and EU-method C.6. The test item was biodegraded 26 % at day 28 in the Closed Bottle test. In the prolonged Closed Bottle test this compound was biodegraded 53 % at day 140. Therefore it can be concluded that the test item is not ready biodegradable, but inherently biodegradable.

The performance of simulation tests for biodegradation in water and sediment is scientifically unjustified.

REACH Regulation No. 1907/2006, Annex IX, Sect. 9.2.1.2, Col. 2, states as follows:

“9.2.1.2: The study need not to be conducted:

-if the substance is readily biodegradable, or

-if direct and indirect exposure of sediment is unlikely. ”

Direct and indirect exposure of the test item to water and sediment 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.Furthermore,TBPND was considered to be inherently biodegradable, therefore simulation testing for biodegradation in water was considered not scientifically justified.

 

The performance of tests for biodegradation in soil is scientifically unjustified.

REACH Regulation No. 1907/2006, Annex IX, Sect. 9.2.1.3, Col. 2, states as follows:

“9.2.1.3: The study need not to be conducted:

-if the substance is readily biodegradable, or

-if direct and indirect exposure of soil is unlikely. ”

Direct and indirect exposure of the test item to soil is highly unlikely. Due to the unstable nature of organic peroxides, it can be assumed that upon contact with soil and organic matter, the test item undergoes rapid degradation resulting in the formation of respective alcohols and acids. Furthermore, TBPND was considered to be inherently biodegradable, therefore simulation testing for biodegradation in sediment was considered not scientifically justified.

 

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

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

“9.3.2Thestudy need not be conducted if:

-the substance has a low potential for bioaccumulation (for instance a logKow<= 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. Therefore, TBPND was considered to have no bioaccumulation potential. Using EPIWIN 4.1 a BCF of 925 L/Kgwwtwas calculated indicating no potential for bioaccumulation.

 

The Koc was measured using the HPLC method. This method is applicable for substances which have logKocvalue ranging from 1.5 to 5.0. The adorption coefficient was estimated to be 4424 and the logKocwas 3.64.