5,12-dihydro-2,9-dimethylquino[2,3-b]acridine-7,14-dione

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 October 2006

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Test procedure according to method of Analytical Expert Group ETAD (Ecological and Toxicological Association of Dyes and Organic Pigment Manufacturer)

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

test procedure similar to OECD 105

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

yes

Remarks:

modified taking into account the very low solubility of the test substance

Principles of method if other than guideline:

The method for the determination and analytical investigation is according to the method that was agreed upon at the "Analytical Experts Meeting" of ETAD (Basel) on January 12, 2005.

GLP compliance:

no

Type of method:

flask method

Water solubility:

5.6 µg/L

Temp.:

24 °C

pH:

ca. 7

Remarks on result:

other: mean of 3 measurements

individual results: 3.0 µg/L - 5.1 µg/L - 8.7 µg/L

mean: 5.6 µg/L

Conclusions:

the test substance is practically insoluble in water (< 0.1 mg/L)

Cross-reference 2

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

solubility in organic solvents / fat solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Test procedure according to method of Analytical Expert Group ETAD (Ecological and Toxicological Association of Dyes and Organic Pigment Manufacturer)

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: Analytical Expert Group ETAD

Principles of method if other than guideline:

Test procedure according to method of Analytical Expert Group ETAD (Ecological and Toxicological Association of Dyes and Organic Pigment Manufacturer)

GLP compliance:

no

Medium:

n-octanol

Solubility:

0.84 mg/L

Temp.:

24 °C

Remarks on result:

other: mean of three measurements

individual results: 0.82 mg/L - 0.85 mg/L - 0.84 mg/L

mean: 0.84 mg/L

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: ETAD Analytical Expert Group

Version / remarks:

method for substances with very low solubility in both, water and n-octanol

Principles of method if other than guideline:

Based on the determined solubilities in water and n-octanol the partition coefficient was calculated.

GLP compliance:

no

Type of method:

estimation method (solubility ratio)

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

5,12-dihydro-2,9-dimethylquino[2,3-b]acridine-7,14-dione

EC Number:

213-561-3

EC Name:

5,12-dihydro-2,9-dimethylquino[2,3-b]acridine-7,14-dione

Cas Number:

980-26-7

Molecular formula:

C22H16N2O2

IUPAC Name:

2,9-dimethyl-5,7,12,14-tetrahydro-5,12-diazapentacene-7,14-dione

Test material form:

solid: nanoform

Study design

Analytical method:

photometric method

Results and discussion

Partition coefficient

Partition coefficient 1

Type:

Pow

Partition coefficient:

150

Temp.:

24 °C

pH:

ca. 7

Partition coefficient 2

Type:

log Pow

Partition coefficient:

2.2

Temp.:

24 °C

pH:

ca. 7

Any other information on results incl. tables

Partition coefficient values (n-octanol/water) are difficult to measure for chemicals with low solubility in both water and octanol, which applies to a variety of pigments.

The water and n-octanol solubility values of individual pigments could be determined with an analytical method that was agreed upon at the Analytical Experts Meeting of ETAD (Basel) on 12 January 2005 (ETAD: The Ecological and Toxicological Association of Dyes and Organic Pigments Manufacturers).

According to the “Guidance on Information Requirements and Chemical Safety Assessment” (chapter R.7.1.8; ECHA, 2008) and according to Regulation (EC) No 440/2008 (chapter A.8), such a calculation is an accepted method for the estimation of partition coefficients of substances for which other methods (according to e.g. OECD TG 107 and 117) are not feasible or unsuitable.

Pow and log Pow were calculated from equilibrium concentrations in n-octanol (see section 4.9) and in water (see section 4.8) with the following equation: Pow = equilibrium concentration in n-octanol / equilibrium concentration in water. Pow values were converted to log Pow values by taking the decadic logarithm.

Both solubilites were determined with the same test material batch and at the same temperature

Applicant's summary and conclusion

Conclusions:

The test substance has a log Pow of 2.2.