Oxoaluminium, C16-C18-alkyl esters

Endpoint summary

Description of key information

Based on the available information the substance would be readily biodegradable in isolated form but is not readily biodegradable when in situ in base oil, the form in which it is typically marketed and used. As such, the information to be taken into account for any hazard/risk/persistence assessment is that the substance is not readily biodegradable.

Additional information

The substance is not expected to leach out or partition from the grease base into water due to its poor water solubility and strong physical interactions with the grease matrix. On the basis of the information provided, assessment of the hazard of the isolated substance is not considered to be relevant. Based on the available information the substance would be readily biodegradable in isolated form but is not readily biodegradable when in situ in base oil, the form in which it is typically marketed and used. As such, the information to be taken into account for any hazard/risk/persistence assessment is that the substance is not readily biodegradable.

The water solubility of the substance as a 50% w.w. concentration in pharmaceutical white oil has been determined to be less than 0.00015 g/L of solution at 20.0 ± 0.5°C, based on test substance. The substance is used as thickeners in lubricants and greases in open and closed systems and thus there is no direct application to the aquatic environment. The substance is highly insoluble and has no identified uses in which it would enter the aquatic or sediment compartments or the sewage treatment system in significant quantities.

The biodegradation in soil endpoint can be waived if direct and indirect exposure of soil is unlikely. The vapour pressure of the substance as a 50% w.w. concentration in pharmaceutical white oil has been determined to be 0.00015 Pa at 25°C. The substance has low volatility and so aerial deposition is unlikely. The substance is not applied directly or expected to be exposed to soil during use and thus, terrestrial exposure is considered to be unlikely. The substance is used as thickeners in lubricants and greases in open and closed systems and thus there is no direct application to soil. The substance also has no identified uses in which it would enter the sewage treatment system in significant quantities which would lead to exposure to agriculture from the spreading of sewage sludge. The majority of greased parts are designed to keep the grease within the contact zone. A large proportion of light to medium duty grease-lubricated parts are sealed for life and the user will not interact with the grease during any time of the part’s use from purchase to disposal. Due to the nature of the grease as a semi-solid, even in catastrophic failure, it will remain within the part and not be released. Some applications require a grease to be used as a total loss lubricant, such as on rail tracks, heavy duty trucks, spindles on agricultural crop pickers and marine applications. In these applications, there are voluntary/compulsory schemes in place that limit the type of product used based on its toxicity, ecotoxicity and biodegradability (e.g. Nordic Swan, Ecolabel, Blaue Engel, VGP).