N,N'-(2,5-dichloro-1,4-phenylene)bis[4-[[2-chloro-5-(trifluoromethyl)phenyl]azo]-3-hydroxynaphthalene-2-carboxamide]

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Pigment Red 242 (nano form): Negative (Ames, CA)

Analogue substance: Pigment Red 166 (not specified form): Negative (Ames, OECD 476, OECD 474)

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

Analogue substance Pigment Red 166 (not specified form): Negative (MN)

Link to relevant study records

Reference

Reference 1

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions (purity not reported)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Version / remarks:

(1997)

GLP compliance:

no

Type of assay:

micronucleus assay

Species:

hamster, Chinese

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: male: 23-30 g, female: 21-29 g
- Housing: single cage (individually)
- Diet (e.g. ad libitum): NAFAG No. 924
- Water (e.g. ad libitum): ad libitum
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22-24°C
- Humidity (%): 46 - 70%
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: PEG 400
- Concentration of test material in vehicle: 62.5 , 125, 250 mg/mL
- Amount of vehicle (if gavage or dermal): 20 mL/kg

Details on exposure:

after 48 hrs of first application animals were sacrificed

Duration of treatment / exposure:

48 hrs

Frequency of treatment:

2 doses per animal; once daily

Post exposure period:

24 hrs

Remarks:

Doses / Concentrations:
1250 mg/kg bw
Basis:

Remarks:

Doses / Concentrations:
2500 mg/kg bw
Basis:

Remarks:

Doses / Concentrations:
5000 mg/kg bw
Basis:

No. of animals per sex per dose:

6

Control animals:

yes, concurrent vehicle

Positive control(s):

cyclophosphamide:
- Route of administration: oral
- Doses / concentrations: 128 mg/kg in 20 mL/kg PEG 400

Tissues and cell types examined:

Blood cells of bone marrow

Details of tissue and slide preparation:

Bone marrow was harvested from the shafts of both femurs. In a siliconized pipette filled with approx. 0.5 μL rat serum the bone marrow was drawn up. Small drops of the mixture were transferred on the end of a slide, and the preparations were air-dried. After 3 hrs, the slides were stained in undiluted May-Gruenwald solution for 2 min then in May-Gruenwald solution/water 1/1 for 2 min and then in Giemsa's, 40% for 20 min. After being rinsed in methanol 55% for 5-8 s and washed off twice in water, they were left immersed in water for approx. 2 min. After rinsing with distilled water and air-drying, the slides were cleared in Xylol and mounted in Eukitt.

Evaluation criteria:

1000 bone marrow cells each were scored per animal and the following anomalies were registered: a) Single Jolly bodies, b) fragments of nuclei in erythrocytes, c) micronuclei in erythroblasts, d) micronuclei in leucopoietic cells, e) polyploid cells.

Statistics:

Significance of differences between doses were assessed by chi-square test

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

One female animal of the low-dose group died after the 1st application. Due to lack of dose-dependency and affection of a single animal, a treatment-related but not a substance-related effect is assumed.

In all treatments with the substance and in the negative control, the mean percentage of anormal cells was 0.1 while the positive control substance caused 10% abnormal cells, indicating the absence of a genotoxic effect in this test system and a suitable sensitivity of the test system (see table).

	dose  [mg/kg bw]	average number of cell anomalies per animal
negative control (PEG 400)		0,1
positive control (Cyclophosphamide)	128	10
test substance	1250	0,1
test substance	2500	0,1
test substance	5000	0,1

Conclusions:

Interpretation of results (migrated information): negative

Reference 2

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
[Please provide information for all of the points below. Indicate if further information is included as attachment to the same record, or elsewhere in the dataset (insert links in 'Cross-reference' table)]

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
Please refer to attached read across justification document (Chapter 13).

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Please refer to attached read across document (Chapter 13).

3. ANALOGUE APPROACH JUSTIFICATION
Please refer to attached read across justification document (Chapter 13).

4. DATA MATRIX
Please refer to attached read across justification document (Chapter 13).

Reason / purpose for cross-reference:

read-across source

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

One female animal of the low-dose group died after the 1st application. Due to lack of dose-dependency and affection of a single animal, a treatment-related but not a substance-related effect is assumed.

In all treatments with the substance and in the negative control, the mean percentage of anormal cells was 0.1 while the positive control substance caused 10% abnormal cells, indicating the absence of a genotoxic effect in this test system and a suitable sensitivity of the test system (see table).

	dose  [mg/kg bw]	average number of cell anomalies per animal
negative control (PEG 400)		0,1
positive control (Cyclophosphamide)	128	10
test substance	1250	0,1
test substance	2500	0,1
test substance	5000	0,1

Conclusions:

Interpretation of results (migrated information): negative

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for mutagenicity under Regulation (EC) No. 1272/2008, as amended for the third time in Directive EC 618/2012.