Choline chloride

Viscosity

Link to relevant study record(s)

Reference

Endpoint:

viscosity

Data waiving:

study technically not feasible

Justification for data waiving:

the study does not need to be conducted because the substance is a solid

Description of key information

The study does not need to be conducted as it is technically not feasible: the substance is a solid.

Viscosity of a 75 % aqueous solution of Choline Chloride: 26.2 mPa.s at 20 °C and 14.1 mPa.s at 40 °C (OECD Guideline 114 (Viscosity of Liquids / rotational viscometer))

Key value for chemical safety assessment

Viscosity:

26.2 mPa · s (dynamic)

at the temperature of:

20 °C

Additional information

The viscosity of a 75 % solution of choline chloride was determined in an OECD 114 guideline study, classified as reliable without restrictions (Klimisch 1) and which meets fully the OECD 114 guideline requirements. Hence, the results in general are considered as reliable.

Although the salt choline chloride is a solid compound, it is very hygroscopic and cannot be kept water-free under normal environmental conditions. Furthermore, it is marketed as a 75 % aqueous solution and is therefore the predominantly available form. Hence, it is justified out of scientific reasons and exposure considerations to regard choline chloride as aqueous solution, which requires the performance of the testing for viscosity instead of a particle size distribution. The outcome of this study is considered reasonable, within the scientifically expected ranges and can be used for further risk assessment.

Due to the reliability of the results and the choice of the test method with regard to the predominantly existing form of choline chloride, i.e. a 75 % aqueous solution, the tonnage-driven requirements under REACH are fully met, no datagaps were identified and no further testing is required.