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The substance Benzenepropanoic acid, 3,5 -bis(1,1 -dimethylethyl)-4 -hydroxy-,C7 -9 branched alkyl esters (CAS 125643 -61 -0) cannot be considered as readily biodegradable (EPIWIN prediction performed by Chemservice S.A., 2011).

Experimental results are available for the read-across substance Butyl 3,5 -bis(1,1 -dimethylethyl)-4 -hydroxybenzenepropanoate (CAS 52449 -44 -2), concluding that the substance is neither readily nor inherent biodegradable. All studies were conducted in compliance with the Principles of Good Laboratory Practice (GLP) and the validity criteria of the corresponding guidelines were met, respectively.

In compliance with the Guidelines for Testing of New Chemical Compounds (Kanhogyo No.5, Yakuhatu No.615, 49 Kikyoku No.392, 1974; revised in 1986 and 1987) the substance was found to hydrolyze into water soluble carboxylic acid and alcohol, whereby the alcohol will be degraded by activated sludge (Furukawa, 2000).

According to an experiment conducted in compliance to OECD guideline 301B, the test material attained 6 % degradation after 28 days and therefore does not fulfill the stringent requirements to be considered as readily biodegradable (Mead, 2000).

Another experiment with this substance was conducted according to the "Guidelines for Testing of New Chemical Compounds (Kanliogyo No.5, Yakuhatsu No.615, 49 Kikyoku No.392, 1974; revised in 1998)" to investigate the inherent biodegradation potential (Furukawa, 2001). On day 28, both peaks of the test substance and carboxylic acid appeared on HPLC chromatogram. The residual test substance concentration was about 30 % similar to that in the ready biodegradability test (Furukawa, 2000). It can be concluded that the test substance is not inherently biodegradable.

Furthermore, one experimental result is available for the second read-across substance Benzenepropanoic acid 3,5 -bis(1,1 -dimethylehtyl)-4 -hydroxy-2 -ethylhexylester (CAS 144429 -84 -5). The criteria for "inherent and primary degradability" under the test conditions of the OECD guideline 302C were fulfilled, since the test material attained 45.8 % degradation at day 28, thereby exceeding the pass level of 20 % (Zhang, 2009).

Using category approach by the OECD QSAR Toolbox the test substance was predicted to be for 34.6% biodegradable after 28 days (Chemservice S.A., 2011).

Since the Benzenepropanoic acid, 3,5 -bis(1,1 -dimethylethyl)-4 -hydroxy-, C7 -9 branched alkyl esters (CAS 125643 -61 -0) was predicted to be inherently biodegradable, no further test on biodegradation neither in surface water and sediment nor soil are performed. In accordance with REACH Annex IX, section (water), section (sediment) and section (soil), column 2, respectively, these endpoints can be waived.