Turpentine, oil

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-11-17 to 2010-03-17

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Deviations:

yes

Remarks:

yes (The surface tension result was not corrected using the Harkins-Jordan correction table as the correction is not applicable to the apparatus used. Once calibrated, direct reading for surface tension obtained was within required accuracy of ± 0.5 mN/m.

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Deviations:

yes

Remarks:

yes (The surface tension result was not corrected using the Harkins-Jordan correction table as the correction is not applicable to the apparatus used. Once calibrated, direct reading for surface tension obtained was within required accuracy of ± 0.5 mN/m.

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Key result

Surface tension:

54.8 mN/m

Temp.:

21 °C

Conc.:

0.307 g/L

Remarks on result:

other: The surface tension of a 0.307 g/l solution (TOC) of test material has been determined to be 54.8 mN/m at 21.0 ± 0.5°C. The test material is considered to be a surface-active material.

Results:

Sample solution concentratrion:

Concentrations obtained from the calibration curve are shown in table 1:

Table 1: Sample Solution Concentration

Solution	TOC Concentration (mg/l)
Matrix blank	1.906
Sample	308.8
Mean sample solution concentration = 0.307 g/l

Calibration Factor (f):

The readings, temperatures and the corresponding calibration factors for reverse osmosis water are shown in the table 2:

Table 2: Reverse Osmosis calibration factor

Reading (mN/m)	Temperature (°C)	Literature value (mN/m)	Calibration factor
71.5	21.2	72.53	1.014
72.5	21.2	72.53	1.000
72.5	21.2	72.53	1.000
72.5	21.2	72.53	1.000
72.5	21.2	72.53	1.000
72.0	21.4	72.50	1.007
72.5	21.4	72.50	1.000
Mean Calibration Factor = 1.001

 

Sample Solution readings:

The readings, times and temperatures for the sample solution are shown in table 3:

Table 3: Sample solution readings

Time (Mins)	Reading (mN/m)	Temperature (°C)
83	53.5	21.2
90	54.5	21.2
96	54.5	21.2
100	55.0	21.2
105	54.5	21.2
110	55.0	21.4

 

Mean Reading                  54.7 mN/m

Surface Tension                reading X calibration factor

                                        54.7 X 1.001

                                        54.8 mN/m

Temperature                     21.0 ± 0.5 °C

pH of sample solution    6.51

Conclusions:

A surface tension of a 0.307 g/l solution (TOC) of Crude Sulphate Turpentine was obtained to be 54.8 mN/m. The result was obtained in a reliable study conducted according to OECD 115, and in compliance with GLP. The test substance is considered to be surface active.

Description of key information

Surface Tension: 54.8 mN/m (OECD 115), surface active

Key value for chemical safety assessment

Surface tension:

54.8

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

0.307

Additional information

An aqueous solution surface tension value of 54.8 mN/m at 21°C has been determined for TOPP in a GLP study according to OECD 115. TOPP is considered to be weakly surface active.