Registration Dossier

Administrative data

Endpoint:
toxicity to soil microorganisms
Data waiving:
exposure considerations
Justification for data waiving:
the study does not need to be conducted because direct and indirect exposure of the soil compartment is unlikely
Justification for type of information:
JUSTIFICATION FOR DATA WAIVING

In accordance with column 2 of REACH Annex IX, the testing on terrestrial organisms does not need to be conducted as direct and indirect exposure of the soil compartment is unlikely.

No testing has been proposed for terrestrial endpoints and the endpoints have been waived on the basis that there is expected to be no exposure of the terrestrial environment. The isolated thickener is considered readily biodegradable and the thickener in situ in an inert carrier, such as base oil, is unlikely to come in contact with the terrestrial environment, so the derivation of terrestrial data on the isolated thickener is not considered to be relevant. The substance is used as a thickener in lubricants and greases in open and closed systems so 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. As the thickener in base oil has very low volatility, it is not expected to enter the atmosphere and aerial deposition of the substance will be negligible.

The substance is used as a thickener in lubricants and greases and 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, it will remain within the part and not be released, even in catastrophic failure. 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).

Based on read across from aluminum, benzoate C16-18-fatty acids complexes, the substance is not considered to be acutely toxic to fish, invertebrates or inhibitory to algal growth and the substance is expected to have acute LL or EL50s of >100 mg/L (WAF). Based on data read across from a structural analogue, aluminium salts of benzoate, C16-18 fatty acids complexes, the substance in an isolated form is expected to be readily biodegradable, though the substance in situ in base oil (the form in which it is typically manufactured and used) is not considered readily biodegradable. The substance will dissociate and degrade into inorganic aluminium species and fatty acids. The fatty acid components biodegrade rapidly to carbon dioxide and water and are natural substances with a long history of safe use in foods. Aluminium is expected to have a low potential for bioaccumulation, with BCF of around 36 at pH 7.2 and, at environmental pH (ca 7.0), aluminium will mainly be in the form of essentially insoluble hydrated oxide species which, although likely to absorb onto soil, are not expected to be scientifically relevant as they are naturally abundant in the environment.

The substance is only manufactured in situ in a generic inert carrier, typically base oil, and the substance tested at a 50% w.w. in pharmaceutical white oil did not meet the criteria for ready biodegradability. In realistic use scenarios, the thickeners will be contained in a base oil matrix, with the formulated greases specifically designed to minimise the leaching of the thickener. Commercial greases are designed to have high temperature stability and to be resistant to diffusion of the thickener out of the oil, indicating that the grease structure is robust. Dissolution of grease thickener from grease into water is very unlikely as the thickener is poorly water soluble and the thickener is embedded in the hydrophobic grease matrix and thus is unlikely to leach out. On the basis of these data, the substance, as a grease thickener in situ in base oil, is not expected to be bioaccessible in significant concentrations. Data read across from lithium and calcium salts of fatty acids have shown no leaching of the thickeners from base oil into water and, given the very low solubility of the substance in water, the concentrations of the substance which would be available for adsorption to soil or sediment are limited.

This substance has been registered by a Member of the European REACH Grease Thickeners Consortium (ERGTC). A number of decisions have been made in the dossier with regard to the approach taken for registering the substance including the testing strategy and the justification for waiving certain endpoints. Several of the decisions reflect the technical difficulties of testing the substance and the relevance of data with regard to the potential for exposure, given that the substance typically occurs in situ in base oil. A face to face meeting between the ERGTC and ECHA was held in Helsinki on 8th September 2016 which discussed many of these topics and a copy of the minutes from the meeting are attached to the dossier (See section 13 of IUCLID). Therefore, if there are any queries or concerns which arise when the dossier is reviewed, it is requested that the reviewer discuss these with the ERGTC (ERGTC@wca-consulting.com) as there may be background information and previous discussions between the ERGTC and ECHA which are relevant.

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion