[No public or meaningful name is available]

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02-03 May 2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was conducted according to an internationally recognised method, and under GLP, but test concentration is unclear. Therefore validation applies with restrictions.

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

11 April 2011

Type of method:

plate method

Specific details on test material used for the study:

- Appearance: White powder
- Storage conditions: Test item was stored in a closed vessel at room temperature away from light and humidity.

Key result

Surface tension:

55.8 mN/m

Temp.:

20.1 °C

Conc.:

11.56 mg/L

Table 4.10/1: Measured Values Test Item

 

No. of series	Surface tension
	Mean	Standard Deviation
First Series	58.63	0.40
Second Series	55.81	0.42
Third Series	56.27	0.28

 

Analytical Determinations:

DOC (dissolved organic carbon) analysis of the filtrated test solution was performed. A value of 9.48 mg org. carbon/L was obtained, and the concentration of the test item was calculated from the measured DOC and the stated organic carbon content.

The organic carbon content of 81.99 % was calculated from the molecular formula.

The concentration of the test item was calculated from the measured value 9.48 mg/L and the carbon content using the following equation:

Concentration test item (mg/L)= Measured DOC value in mg/L /Org. C content in %

The concentration was therefore determined with 11.56 mg test item/L.

 

Result Test Item:

During the specified period of time, changes in surface tension were detected. Values between 54.62 and 58.89 mN/m were recorded.

Conclusions:

According to EU A5 criteria, as the result is below the threshold value of 60 mN/m, the substance is considered to have surface-active potential under the experimental conditions.

Executive summary:

The surface tension of the test substance was determined under GLP according to OECD 115/EU A5 guideline, with the plate method.

 

Three experiments were conducted in order to determine the surface tension of a 90 % saturated test item solution. The difference between the first and second measurement series after 58 minutes was too high. Therefore, a third measurement series was performed for verification (after another 61 minutes). As the difference between the second and the third determination was only 0.82%, equilibrium was considered reached. The surface tension of a 90 % saturated test substance at plateau was determined as 55.8 mN/m at 20.1 °C.

The concentration of the test solution was estimated as 11.56 mg test item/L via DOC.

Description of key information

Surface tension = 55.8 mN/m, at 90% saturation expected (ca 11.56 mg/L estimated from DOC), and 20.1°C

According to EU A5 criteria, as the result is below the threshold value of 60 mN/m, the substance is considered to have surface-active potential under the experimental conditions. However, since the structure is not characteristic of a true surfactant, and it is not the intended use of the substance (i.e. not a desired property), this conclusion should be taken with caution.

Key value for chemical safety assessment

Surface tension:

55.8

in mN/m at 20°C and concentration in mg/L:

11.56

Additional information

A reliable experimental study, conducted according to a recognized EC method and under GLP, is available. Despite restrictions on actual concentration tested, it is considered as a key study, and the result is retained as key value.