[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:

From 19 December 2018 to 22 February 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Deviations:

no

GLP compliance:

no

Remarks:

The study was conducted in a facility which operates in accordance with Good Laboratory Practice principles; however no claim of GLP compliance was intended nor is made for this study

Type of method:

ring method

Key result

Surface tension:

ca. 32.3 mN/m

Temp.:

20 °C

Conc.:

2 040 mg/L

Remarks on result:

other: Test substance concentration of 90% of the CMC (2.04 x 10^3 mg/L)

Results

The readings and temperatures for the sample solutions are shown in the following table:

Table1: Surface tension values

Concentration (mg/L)	Reading (mN/m)	Temperature (°C)
3.037 x10^3	36.0	20.0
	31.5	20.0
	31.5	20.0
	31.0	20.0
1.012 x 10^3	37.0	20.2
	33.0	20.2
	32.5	20.2
	32.5	20.2
303.7	46.5	20.2
	44.0	20.2
	44.0	20.2
	43.5	20.2
101.2	53.5	20.2
	50.5	20.2
	50.5	20.2
	50.0	20.2
30.37	59.0	20.4
	57.0	20.4
	57.0	20.4
	57.0	20.4
10.12	65.5	20.4
	64.5	20.4
	64.5	20.4
	64.0	20.4
3.037	70.0	20.4
	69.0	20.4
	69.0	20.4
	68.5	20.4
1.012	70.5	20.4
	70.5	20.4
	70.5	20.4
0.3037	72.5	20.4
	72.5	20.4
	72.5	20.4
0.1012	72.5	20.4
	72.5	20.4
	72.5	20.4

Mean surface tension values were based on the last three readings for a particular concentration which were considered to be constant.

Theconcentration (mg/L), log₁₀[concentration (mg/L)] and mean surface tension values for the sample solutions are shown in the following table:

 

Table2:Theconcentration (mg/L), log₁₀[concentration (mg/L)] and mean surface tension values

Concentration (mg/L)	Log10Concentration	Mean Surface Tension (mN/m)	Solution pH
3.037 x 10^3	3.482	31.3	6.3
1.012 x 10^3	3.005	32.7	6.4
303.7	2.482	43.8	6.2
101.2	2.005	50.3	6.6
30.37	1.482	57.0	n/a
10.12	1.005	64.3	5.9
3.037	0.482	68.8	6.1
1.012	0.005	70.5	6.0
0.3037	-0.518	72.5	6.1
0.1012	0.995	72.5	6.1

The surface tension at a concentration of 90% of the CMC (2.04 x 10³ mg/L) was calculated to be 32.3 mN/m using the equation for Line 1.

Conclusions:

Under the study conditions, the surface tension at a test substance concentration of 90% of the CMC (2.04 x 103 mg/L) in water was determined to be 32.3 ± 0.5 mN/m at 20 ± 0.5ºC; therefore it is surface-active.

Executive summary:

A study was conducted to determine the surface tension of the test substance, using ring method, according to the OECD Guideline 115 and EU Method A.5. Under the study conditions, the surface tension at a test substance concentration of 90% of the CMC (2.04 x 103 mg/L) in water was determined to be 32.3 ± 0.5 mN/m at 20 ± 0.5ºC; therefore it is surface-active (Envigo, 2019).

Description of key information

The surface tension of the test substance was determined using the ring method, according to OECD Guideline 115 and EU Method A.5 (Envigo, 2019).

Key value for chemical safety assessment

Surface tension:

32.3

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

20

Additional information

(surface active)