Hydrogen bis[2-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]benzoato(2-)]chromate(1-), compound with 2-ethylhexylamine (1:1)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: current Guideline study under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Hydrogen bis[2-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]benzoato(2-)]chromate(1-), compound with 2-ethylhexylamine (1:1)

EC Number:

275-864-7

EC Name:

Hydrogen bis[2-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]benzoato(2-)]chromate(1-), compound with 2-ethylhexylamine (1:1)

Cas Number:

71701-15-0

Molecular formula:

C42H44CrN9O6

IUPAC Name:

Chromate(1-), bis[2-[2-[4,5-dihydro-3-methyl-5-(oxo-kO)-1-phenyl-1H-pyrazol-4-yl]diazenyl-kN1]benzoato(2-)-kO]-, hydrogen, compd. with 2-ethyl-1-hexanamine (1:1:1)

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/CaOiaHsd

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Netherlands; B.V. Postbus 6174; NL - 5960 AD Horst ; The Netherlands
- Age at study initiation: 8- 12 weeks
- Weight at study initiation:
- Housing: Single caging
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: yes

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

methyl ethyl ketone

Concentration:

5 - 10 - 25 %

No. of animals per dose:

4

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

Positive control results:

SI = 4,9 at 25 %

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: see table below

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see table below

Any other information on results incl. tables

Test item concentration	Group	Measurement	Calculation			Result
% wv		DPM	DPM-BG*	Number of lymph nodes	DPM per lymph node **	SI
Experiment 1
-	BG I	20,3	-	-	-	-
-	BG II	0	-	-	-	-
-	CG 1	2653,1	2643,0	8	330,4	-
5,0	TG 2	5575,0	5564,9	8	695,6	2,1
10,0	TG 3	10264,2	10254,1	8	1281,8	3,9
25	TG 4	6850,3	6840,2	8	855,0	2,6
Experiment 2
-	BG I	4,0	-	-	-	-
-	BG II	1,4	-	-	-	-
-	CG 1	4797,8	4795,1	8	599,4	-
10,0	TG 2	8090,4	8087,4	8	1010,9	1,7

BG=Background (1 ml 5% trichloroacetic acid) in duplicate

CG=Control Group

TG=Test Group

S.l.=Stimulation Index

*=The mean value was taken from the figures BG I and BG II

**=Since the lymph nodes of the animals of a dose group were pooled, DPM/node was determined by dividing the measured value by the number of lymph nodes pooled

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item was not a skin sensitiser under the described conditions.

Executive summary:

In the study the test item suspended in methyl ethyl ketone was assessed for its possible contact allergenic potential.

For this purpose a local lymph node assay was performed using test item concentrations of 5.0, 10.0, and 25.0%.

The animals did not show any clinical signs during the course of the study and no cases of mortality were observed.

Stimulation Indices (S.I) of 2.1 and 2.6 were determined with the test item at concentrations of 5.0 and 25.0 % (w/v) in methyl ethyl ketone, respectively.

A single increased Stimulation Index of 3.9 occurred at the mid concentration (10 %). To verify the result obtained for this concentration, 10 % (w/v) suspended in methyl ethyl ketone were assayed in a second experiment performed under identical conditions. In experiment 2 a Stimulation Index of 1.7 was measured for the concentration of 10 % (w/v) suspended in methyl ethyl ketone. Thus, the value obtained in experiment 1 could not be confirmed.

The test item was not a skin sensitiser in this assay.