Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Based on read across, (benzoato-O,O')hydroxy(octadecanoato-O,O')aluminium has been shown to be readily biodegradable (Harlan 2013). Because the substance is readily biodegradable, the hydrolysis, biodegradation simulation tests in soil and sediment and adsorption/desorption endpoints have been waived.

The reactions to form the grease thickener occur in-situ during the grease manufacturing process and consequently these grease thickeners only exist in the base oil matrix. The matrix effect, as recognised by the OECD Lubricant Emission Scenario document (OECD 2004), needs to be taken into account as the process of manufacturing the thickener in inert base oil is likely to influence factors such as availability of the thickeners. In the grease manufacturing process unique interactions, more appropriately defined as physical bonding effects, occur between the base oils and the thickener. The chemistry is complex and interactions between the thickener and base oil do not strictly fall under the definitions of a reaction product nor do they act as a simple mixture of components. In realistic use scenarios, the thickener will be contained in base oil, with the formulated greases specifically designed to minimise the leaching of the thickener. Therefore, during use, the concentrations of the substance which would be bioavailable are limited. The proprietary study (Shell Technology Centre, 2013) supports this conclusion by showing that metal ions are not leached from metal grease thickeners contained within base oil when exposed to an aqueous environment.

Reference

OECD (2004) OECD Series on emission scenario documents, Number 10: Emission scenario document on lubricants and lubricant additives. Environment directorate: Joint meeting of the chemicals committee and the working part on chemicals, pesticides and biotechnology. ENV/JM/MONO(2004)21