Registration Dossier

Administrative data

Endpoint:
surface tension
Type of information:
experimental study
Adequacy of study:
key study
Study period:
18/08/2008-17/10/2008
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of relevant results.
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method A.5 (Surface Tension)
Deviations:
yes
Principles of method if other than guideline:
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, the balance and ring assembly used in this test give a direct reading for surface tension that is within the required accuracy (+/- 0.5 mN/m); this is as a result of the reduced ring dimensions.
GLP compliance:
yes (incl. certificate)
Remarks:
UK GLP Standards (Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994)).
Type of method:
ring method

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Surface tension
Surface tension:
72.3 mN/m
Temp.:
21.8 °C
Conc.:
1.02 g/L

Any other information on results incl. tables

Calibration factor (f)

The readings, temperatures and the corresponding calibration factors for glass double-distilled water are shown in the following table:

Reading (mN/m)

Temperature (ºC)

Literature Value (mN/m)

Calibration Factor

72.5

21.8

72.44

0.999

72.5

21.8

72.44

0.999

72.5

21.8

72.44

0.999

72.5

21.8

72.44

0.999

72.5

21.8

72.44

0.999

72.5

21.8

72.44

0.999

72.5

21.8

72.44

0.999

Mean Calibration Factor = 0.999

Sample solution readings

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

Time (mins)

Reading (mN/m)

Temperature (ºC)

88

72.0

21.8

113

72.5

21.8

123

72.5

21.8

134

72.5

21.8

143

72.5

21.8

153

72.5

21.8

Mean reading                    :   72.4 mN/m
Surface tension                  = reading x calibration factor
                                         = 72.4 x 0.999
                                         = 72.3 mN/m
Temperature                      :   22.0 ± 0.5ºC
pH of sample solution        :   6.5

Applicant's summary and conclusion

Conclusions:
The surface tension of a 1.02 g/l solution of test material has been determined to be 72.3 mN/m at 22.0 ± 0.5 deg C. The test material is considered not to be a surface-active material.
Executive summary:

The determination was carried our using a White Electrical Institute interfacial tension balance and a procedure based on the ISO 304 ring method. With the exception of the following deviation, the experimental procedure used complied with that specified in Method A5 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

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, the balance and ring assembly used in this test give a direct reading for the surface tension that is within the required accuracy (± 0.5 mN/m); this is as a result of the reduced ring dimensions.

The deviation has been considered not to have affected the integrity of the study.

Under the conditions of the test the substance 1.02 g/l in water) has been determined to be 72.3 mN/m at 22.0 ± 0.5oC. The substance is considered not to be surface-active.