4,4'-Isopropylidenediphenol, ethoxylated

Endpoint summary

Description of key information

The environmental fate and behaviour of the registered substance was determined using a combination of reliable data on BPA 1-4.5EO and BPA 2EO, valid QSAR predictions and expert assessments.

 

Two studies were conducted to assess the octanol-water partition coefficient of BPA 1-4.5EO. It was concluded that the substance had a Log Kow between 2 and 3.2 at 23°C, and a Log Kow between 2.77 and 3.94 at 30°C. These values are indicating that BPA 1-4.5EO is not expected to be bioaccumulative. This is supported by a study conducted to assess the aquatic bioaccumulation of BPA 2EO. The BCF of the test substance was found to be < 41.7 at a concentration of 3.84 µg/L, and < 4.2 at a concentration of 38.5 µg/L, indicating that BPA 2EO is not bioaccumulative in accordance with Annex XIII of REACH.

 

Biodegradation studies were performed on BPA 1-4.5EO and BPA 2EO. Results of these studies suggest that the registered substance is inherently biodegradable but not readily biodegradable.

An expert assessment had been done and the report concluded that 4,4'-isopropylidenediphenol is hydrolytically stable. However, ECHA did not accept the approach and a study was requested. Therefore, 4,4-isopropylidenediphenol, ethoxylated (BPA-2EO) is currently being assessed for the purpose of the evaluation of hydrolysis as a function of pH using the OECD TG 111. This study has been planned and commissioned to Innovative Environmental Services (IES) Ltd, Benkenstrasse 260, 4108 Witterswil, Switzerland. Receipt of the draft study report from the CRO is expected to be on February 2021.

The reason for such a delay in reference to ECHA 30 November 2020 deadline (Refs: CCH-D-2114489551-41-01/F), are explained in a separate letter, attached to this dossier. 

An assessment of the adsorption/desorption of BPA 1-4.5EO was performed based on QSAR calculations and available data on the physicochemical properties of the substance. It was concluded that the substance had a Log Koc in the range of 1.5 – 2.0, indicating that it will be weakly adsorbed to soils, sediments and organic matter.

 

A Chemical Safety Assessment (CAS) was performed in accordance with Annex I of REACH. It concluded that further investigation of the degradation of BPA-EO was required as the substance is not ready biodegradable and exposure to the environment cannot be excluded based on the uses associated with BPA-EO. The freshwater sediment was identified as the environmental compartment where exposure to the substance was the highest, it is therefore proposed to perform sediment simulation testing on the registered substance. It is not considered relevant at this stage to perform biodegradation testing in soil as this environmental compartment is exposed to lower concentrations of BPA-EO.