Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

On the basis of experimental data, and supported with QSAR data, category members are not considered readily biodegradable. Category members only ever occur within a base oil grease designed to minimise leaching and they are likely to reside within the hydrophobic base oil grease matrix. The predicted physical-chemical properties (water solubility, vapour pressure and octanol-water partition coefficient), coupled with the fact that the substances are only ever manufactured within a base oil grease indicate that environmental exposures to air, soil and water compartments will be severely limited. 

Reactions to form the grease thickener occur in situ in base oil during the grease manufacturing process and consequently these grease thickeners normally 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 an 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 thickeners. 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 is limited.

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

Additional information