Choline hydroxide

Appearance / physical state / colour

Link to relevant study record(s)

Reference

Endpoint:

appearance / physical state / colour

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-06-01 to 2012-07-04

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Company data, no study explicitly performed but included in study reports to describe the test item.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline required

Principles of method if other than guideline:

Visual and olfactoric inspection of the test item

GLP compliance:

not specified

Physical state at 20°C and 1013 hPa:

liquid

Remarks:

aqueous solution

Form:

other: aqueous solution

Colour:

colourless to light yellow

Odour:

other: nearly odorless

Substance type:

organic

Conclusions:

The data source was classified as Klimisch 2, the description can be considered to be reliable and available data is sufficient to describe the test item. It should be noted that the substance Choline hydroxide is produced, supplied and marketed in the presence of water; and as such the physical state of the test item is under real conditions liquid.

Executive summary:

The test item (provided as an aqueous solution) is a colourless to light yellow and nearly odourless aqueous solution, which is liquid at 20 °C and 1013 mbar.

It should be noted that the substance Choline hydroxide is produced, supplied and marketed in the presence of water; and as such the physical state of the test item is under real conditions liquid.

Description of key information

The pure substance is very hygroscopic and only market in aqueous solution as manufactured. Therefore, the pure substance is accordingly not isolated from the solution in addition due to the hygroscopic properties it would not stay dry for an extended period of time.

Theoretically, the pure substance is expected to be a crystalline solid.

The available Key study investigated the registered substance in water. Choline hydroxide as an aqueous solution is a colourless to light yellow and nearly odourless liquid.

Key value for chemical safety assessment

Physical state at 20°C and 1013 hPa:

liquid

Form:

liquid

Colour:

colourless

yellow

Colour intensity:

transparent

Additional information

The substance itself is expected to be a crystalline solid, but as the pure substance is very hygroscopic, the substance is normally distributed as an aqueous solution and hence it is characterized as such. Choline hydroxide as an aqueous solution is a colourless to light yellow and nearly odourless liquid (Taminco, 2013).

As this is the available form in which it is distributed, the risk assessment should be performed with the substance in this form. This will have i.a. impact on the risk arising from inhalation, since no inhalable dust is formed, or on the necessity to perform the testing for viscosity instead of particle size distribution (see related IUCLID chapters).