tert-butyl peracetate

Endpoint summary

Description of key information

Stability

Phototransformation in air

Based on calculations with computer programme SRC AOP v1.92 (EPISuite v4.11), the degradation rate constant with OH radicals (concentration: 1.56E+6 molecule/cubic cm) is 0.544 cubic cm/molecules*s. This equals a half-life in air of 19.6662 d.

 

Hydrolysis
The rate constant k and half-life were determined at 20 °C for pH 4 = 8.5E-5 h-1 and 8122 h, respectively, for pH 7 = 8.8E-4 and 784 h, respectively, and for pH 9 = 0.0217 h-1 and 32 h, respectively.

 

Biodegradation

Biodegradation in water: screening tests

In order to assess the biotic degradation, a ready biodegradability test was performed which allows the biodegradability to be measured in an aerobic aqueous medium. The ready biodegradability was determined in the Closed Bottle test according to slightly modified OECD and EEC Guidelines, and in compliance with the OECD principles of Good Laboratory Practice. In the biodegradability tests, microorganisms are inoculated into a chemically defined liquid medium containing the test substance as sole carbon and energy source. The test compound is exposed to the inoculum, consisting of relatively low numbers of microorganisms from an activated sludge plant, under aerobic conditions for a period of at least 28 days.The test was prolonged because the pass level was not reached at day 28. The test substance caused no reduction in the endogenous respiration. The test substance is therefore considered to be non-inhibitory to the inoculum. The biodradation of the test substance was 4 %. Hence, the test substance was not biodegraded in the Closed Bottle test (28 days and prolonged) and should therefore not be classified as readily biodegradable. The reference substance, sodium acetate, was degraded 69 % of its theoretical oxygen demand after 14 days.

 

Bioaccumulation

Bioaccumulation: aquatic/sediment

Using an experimental determined octanol-water partition coefficient (log Kow) of 1.60, a bio-concentration factor of 4.514 L/kg ww was calculated with BCFBAF v3.01 (EPI Suite v4.11).Therefore, the test substance is not expected to bioaccumulate.

 

Transport and Distribution

Adsorption/ desorption

The soil adsorption coefficient (Koc) was calculated using EPI Suite KOCWIN v2.00 program. Using the molecular connectivity index (MCI) method, the Koc was calculated to be 10.88 L/kg and log Koc to be 1.0368, respectively, at 25 °C. Using the Kow method the Koc was calculated to be 38.09 L/kg and Log Koc to be 1.5808, respectively, at 25 °C. The calculated log Koc using the log Pow method was regarded as most reliable because this value was based on a measured log Pow of the substance. The Koc of 38.09 L/kg was regarded as worst case assumption. Adsorption to solid soil phase is not expected.