5-bromo-1,3-dichloro-2-fluorobenzene

pH

Administrative data

Endpoint:

pH

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 122 (Determination of pH, Acidity and Alkalinity)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

5-bromo-1,3-dichloro-2-fluorobenzene

EC Number:

640-454-2

Cas Number:

17318-08-0

Molecular formula:

C6H2 BrCl2F

IUPAC Name:

5-bromo-1,3-dichloro-2-fluorobenzene

Test material form:

liquid

Reagents

Reagent:

water

Results and discussion

pH value

Key result

pH value:

6.46

Temp.:

20 °C

Concentration:

1 other: % w/v

Any other information on results incl. tables

On preparation of the initial duplicate samples (determination 1 and determination 2), variance between the final, stable pH values of approximately 0.8 units was obtained. Further duplicate determinations were therefore performed with the addition of potassium chloride as a background electrolyte, as instructed in the OECD methodology. However, a degree of inter-sample variance remained.

This was concluded not to impact on the integrity or validity of the study outcome, with all four results giving an approximately neutral sample solution pH. As the inclusion of the potassium chloride solution did not greatly improve the sample solution pH value repeatability, but was a valid procedure in compliance with the OECD method, all four determinations have been included in the calculation of the mean pH value reported.

Applicant's summary and conclusion

Conclusions:

The pH value of the test item, as a 1% w/v aqueous dispersion, has been determined to be 6.46 at 20 ºC. This value was the mean of four replicate sample preparations; with individual sample pH values being obtained in the range 6.11 and 6.97.

Executive summary:

The pH value of the substance, as a 1% w/v aqueous dispersion, was determined under GLP in accordance with OECD TG 122.

The high purity water, with a specification of resistance >18.2 MΩ and TOC <5 ppb, was pre-equilibrated to 20 °C before use.

Each sample was then transferred to a sample cup, allowed to settle for a period of 1 minute and the pH value then determined.

The pH value was recorded from the pH meter, without stirring of the sample, after a period of 1 minute equilibration and a second reading was recorded after a period of 2 minutes equilibration. If the difference between the two readings did not exceed 0.1 pH units, the pH value was considered stable. If a pH drift greater than 0.1 pH units was observed between the two readings, a final pH value reading was taken after 10 minutes equilibration.

On preparation of the initial duplicate samples (determination 1 and determination 2), variance between the final, stable pH values of approximately 0.8 units was obtained. Further duplicate determinations were therefore performed with the addition of potassium chloride as a background electrolyte, as instructed in the OECD methodology. However, a degree of inter-sample variance remained.

This was concluded not to impact on the integrity or validity of the study outcome, with all four results giving an approximately neutral sample solution pH. As the inclusion of the potassium chloride solution did not greatly improve the sample solution pH value repeatability, but was a valid procedure in compliance with the OECD method, all four determinations have been included in the calculation of the mean pH value reported.