(1-methylethyl)-1,1'-biphenyl

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Publication meets basic scientific principles, limited documentation

Qualifier:

no guideline followed

Principles of method if other than guideline:

Water solubility was determined following the principles of the flask method of OECD TG 105. Test material was equilibrated with glass distilled water at 25°C and the test substance concentration in the aqueous phase was determined by GLC.

GLP compliance:

no

Type of method:

flask method

Water solubility:

0.6 mg/L

Temp.:

25 °C

Remarks on result:

other: pH not reported

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
Using the principle procedure of the flask method of OECD TG 105, the water solubility of isopropylbiphenyl was determined to be 0.6 mg/L.

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

experimental part 2011-09-2 - 2011-09-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

yes

Remarks:

; bed volume, temperature, loading of support

GLP compliance:

yes (incl. QA statement)

Type of method:

column elution method

Water solubility:

0.482 mg/L

Temp.:

25 °C

pH:

8

Concentrations of Ruetasolv BP 4103 measured in samples eluted from column

 

Sample	Concentration [mg/L]
	at 0.4 mL/min	at 0.2 mL/min
1	0.470	0.457
2	0.525	0.473
3	0.493	0.474
4	0.527	0.427
5	0.478	0.490
Mean	0.499	0.464
Overall	0.482

 

All samples were checked negative for colloidal dispersed material utilising the Tyndall effect.

 

The distribution of the two main isomers of Ruetasolv BP 4103 altered from 46.57 % of isomer A and 53.43 % of isomer B in the calibration standards to 52.94 % of isomer A and 47.06 % of isomer B in the test item samples.

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
The water solubility of (1-methylethyl)-1,1'-biphenyl was determined to be 0.482 mg/L in a valid column elution test accroding to OECD TG 105.

Reference 3

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2003 Oct 06 to 2004 Jan 01

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study, but limited analytical documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

GLP compliance:

yes

Type of method:

column elution method

Water solubility:

0.28 mg/L

Temp.:

20 °C

pH:

5.1

Remarks on result:

other: (pH of the purified water used for the test was 5.1)

Details on results:

The test item remaining on the quartz sand was 0.46 %. This amount would be sufficient to saturate 67 l of water.

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)

Reference 4

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented study report which meets basic scientific principles

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline followed

Principles of method if other than guideline:

The nephelometric technique of determining water solubility was use. Light scattering over an appropriate concentration range is measured, and solubility is determened at the concentration where turbidity values start to increase (DOW in-house method).

GLP compliance:

no

Type of method:

other: light scattering

Water solubility:

0.4 mg/L

Remarks on result:

other: Temp. not specified

Details on results:

See under "Attached background material"

From the equations of the straight "soluble" and "insoluble" sections of the turbidity plot, a value of 0.4 mg/L was calculated for the water solubility of (mono)isopropylbiphenyl (60/40 mixture of 3- and 4-isomer).

(section of plot representing soluble concentrations: y = 0.12211x + 0.544443)

(section of plot representing concentration above solubility: y = 1.39428x + 0.0773444)

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
Using the nephelometric technique (turbidity measerements of a series of test substance concentrations in water), the water solubility of isopropylbihenyl (60/40 mixture of 3- and 4-isomer) was determined to be 0.4 mg/L.

Reference 5

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Acceptable, adequately-documented study report which meets basic scientific principles. However, result not explicable.

Qualifier:

no guideline followed

Principles of method if other than guideline:

The method used resembles OECD TG 105 but shows some restrictions.
General procedure: An excess of test substance is stirred in distilled water for 24 h. After centrifugation, aqueous samples are extracted twice with hexane. The hexane extracts are concentrated and the content of test material is measured by GC analysis.

GLP compliance:

no

Remarks:

pre-GLP study

Type of method:

flask method

Remarks:

pre-guideline study

Water solubility:

0.051 mg/L

Remarks on result:

other: temperature and pH not specified

Conclusions:

Interpretation of results (migrated information): insoluble (< 0.1 mg/L)
Compared to current guidelines, the method used has some shortcomings. According to OECD TG 105, the column elution method should be used for substances with this low solubility. In addition, basic controls are not employed. There are only one and not three replicates set up. The establishment of saturation equilibrium (samples at different time points) was not demonstrated. Temperature is not strictly controlled.

Description of key information

Water solubility of (1-methylethyl)-1,1'-biphenyl was determined in a GLP guideline study according to OECD TG 105 using the column elution method. In three other valid experimental studies partly using different methods, similar results were obtained.

Key value for chemical safety assessment

Water solubility:

0.482 mg/L

at the temperature of:

25 °C

Additional information

Water solubility of (1-methylethyl)-1,1'-biphenyl was determined in five experimental studies. Two were GLP guideline studies using the column elution method (Lange/NOACK 2012 and Infracor 2004). Mendoza/DOW 1981 applied a special nephelometric method utilising light scattering/turbidity to characterise the concentration dependent presence of dissolved or suspended material in the aqueous preparations. Addison 1983 and Ozburn et al 1980 adopted the flask method. Results of the first four studies fall in the same range (0.482, 0.28, 0.4 and 0.6 mg/L, respectively). Water solubility of Ozburn was one order of magnitude lower (0.051 mg/L). This study was disregarded.

The studies of Lange/NOACK and Infracor are guideline studies under GLP conditions with a reliability of 1. The method used is most appropriate with respect to the solubility of the substance. The guideline study with the result fitting better in the range of solubilities determined was selected to represent the water solubility of (1-methylethyl)-1,1'-biphenyl.