Terephthalaldehyde

Partition coefficient

Administrative data

Endpoint:

partition coefficient

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

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

Terephthalaldehyde

EC Number:

210-784-8

EC Name:

Terephthalaldehyde

Cas Number:

623-27-8

Molecular formula:

C8H6O2

IUPAC Name:

benzene-1,4-dicarbaldehyde

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

Batch (Lot) Number: 180401
Expiry date: 01 April 2020 (retest date)
Physical Description: Light yellow powder
Purity/Composition: 99.6%
Storage Conditions: At room temperature

Study design

Analytical method:

other: ultra performance liquid chromatographic method with spectrophotometric detection

Results and discussion

Partition coefficient

Partition coefficient 1

Key result

Type:

Pow

Partition coefficient:

ca. 11

Temp.:

20.1 °C

pH:

> 6.6 - <= 6.8

Partition coefficient 2

Key result

Type:

log Pow

Partition coefficient:

ca. 1

Temp.:

20.1 °C

pH:

>= 6.6 - <= 6.8

Any other information on results incl. tables

P_owCalculation

The P_owof the test item was calculated to be 7.9(log P_ow0.9) using the Rekker calculation method.

pK_aValues

The pK_avalues in the logarithm range of 1 - 14 for acidic and basic groups in the molecular structure of the test item were calculated using the Perrin calculation method. The results are given inTable 7.

Table 7          
pKa Values of the Test Item

Acidic			Basic
ARCHO		pKa13.46		none

 Shake Flask Method

The results of the shake flask method are given inTable 8andTable 9.

The analyzed concentration of the stock solution was 0.77 g/L. Based on this the nominal quantity of the test item in the test samples was 1.54 mg. The recoveries were determined according to this value.

The log P_owvalues were within the criterion range of ± 0.3 log units. The P_owand log P_owof the test item is given as the mean value of all measurements.

No test item was detected in the pretreated samples from the blank mixture. 

Table 8          
P_owof the Test Item

Ratio n-octanol : water [v:v]	Analyzed concentration		Pow		log Pow	pH
	n-octanol [g/L]	water [g/L]	individual	mean
1:1	0.214	0.0221	9.7x10^0	9.9x10^0	1.0	6.8
	0.225	0.0222	1.0x10^1		1.0	6.7
1:2	0.347	0.0312	1.1x10^1	1.1x10^1	1.0	6.7
	0.336	0.0315	1.1x10^1		1.0	6.7
2:1	0.187	0.0171	1.1x10^1	1.2x10^1	1.0	6.6
	0.207	0.0170	1.2x10^1		1.1	6.6
Mean			1.1x10^1		1.0
Standard deviation			8.6´10^-1

 

 

Table 9          
Recoveries

Ratio n-octanol : water [v:v]	Analyzed quantity			Recovery [%]
	n-octanol [mg]	water [mg]	total [mg]
1:1	1.29	0.133	1.42	92
	1.35	0.133	1.48	96
1:2	1.39	0.249	1.64	106
	1.34	0.252	1.60	104
2:1	1.50	0.0685	1.56	102
	1.66	0.0680	1.72	112

Applicant's summary and conclusion

Conclusions:

The shake flask method was applied for the determination of the partition coefficient (Pow) of Terephthaldehyde.
The Pow value of the test item was 1.1x 10^1. It corresponds with a log Pow value of 1.0.