Registration Dossier

Environmental fate & pathways

Hydrolysis

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

BPA-DA was determined to be hydrolytically unstable at pH 2, 5-6 and 9 at 23 °C.

Key value for chemical safety assessment

Additional information

The hydrolytic stability of BPA-DA was investigated in accordance with OECD 111 under GLP conditions, though the study plan was not fully executed because of low water solubility and rapid hydrolysis. Alternative methods were therefore used (Vizon SciTec Inc., 2005). The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

First order half-lives of BPA-DA in acetonitrile:aqueous solution (60:40, v/v) at 23 °C are 1.5, 2.0 and 2.5 h at pH 4, 7 and 9, respectively. Given that the estimated BPA-DA half-lives were obtained at high acetonitrile co-solvent concentration, and that the hydrolysis rates should be faster in the absence of co-solvent (due to the higher concentration of water), BPA-DA should be considered hydrolytically unstable at pH 2, 5 -6 and 9 at 23 °C, based on the OECD stability criterion of hydrolysis half-life greater than 1 year at 25 °C (OECD, 2004).

The half-life of the primary hydrolysis product BPA-TA was extrapolated from a preliminary test at 50 °C and was considered to be > 1 year at pH 4, 7 and 9 at ambient conditions.

 

The hydrolytic stability of the primary hydrolysis product BPA-TA (4,4-Bisphenol A Tetra-Acid, CAS No. 38103-05-8) was investigated in accordance with OECD 111 under GLP conditions (Springborn Smithers Laboratories, 2009). The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

Less than 10 % degradation of the substance was observed after 5 days (half-life greater than 1 year) in the sterile pH 4, pH 7 and pH 9 buffer samples. Based on the results of this study, BPA-TA was considered to be hydrolytically stable and no additional testing is required.