Potassium carbamoylcarbamate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to GLP/OECD guideline without deficiency.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

1

Reference substance name:

Potassium carbamoylcarbamate

EC Number:

247-728-7

EC Name:

Potassium carbamoylcarbamate

Cas Number:

26479-35-6

Molecular formula:

C2H3KN2O3

IUPAC Name:

potassium N-carbamoylcarbamate

Test material form:

solid: particulate/powder

Remarks:

migrated information: particulates

Details on test material:

- Name of test material (as cited in study report):Potassium Allophonate
- Physical state:powder
- Analytical purity:83.8%

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source:Nulliparous, non-pregnant female CBA/CaCrl strain mice obtained from Charles River (UK) Ltd, Margate.
- Age at study initiation: 8 to 10 weeks old.
- Weight at study initiation: 15 to 20 g
- Housing:Group housed during acclimatisation and individually housed from Day –1 in cages.
- Diet (e.g. ad libitum):SQC(E) Rat and Mouse Maintenance Diet No 1, from Special Diets Services Ltd, Witham, UK was freely available to the animals at all times.
- Water (e.g. ad libitum):Mains water was provided, ad libitum, via cage-mounted water bottles.
- Acclimation period: 8 to 15 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C):20 to 24 degrees C
- Humidity (%):45 to 65%
- Air changes (per hr):15 to 20
- Photoperiod (hrs dark / hrs light):12/12

IN-LIFE DATES: From 17 January 2012 To 31 January 2012

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

0, 10%, 25%, 50% w/v

No. of animals per dose:

5

Details on study design:

RANGE FINDING TESTS: A preliminary screening test was performed with one mouse. The mouse was treated by daily application of 25 µL of the test
article at the maximum suitable concentration (50% w/v in DMSO) to the dorsal surface of each ear for three consecutive days (Days 1, 2 and 3). The mouse was observed daily for five days from the initiation of treatment. Any signs of toxicity or irritation during this period were recorded.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures:3
- Exposure period: 24 hours
- Site:Outer aspect of both auditory pinnae.
- Frequency of applications:once daily
- Duration:Once daily on Days 1, 2 and 3.
- Concentrations: 0.25 mL/pinna

B. CHALLENGE EXPOSURE
- No. of exposures:1
- Day(s) of challenge:1
- Site: Tail vein injection.
- Concentrations:0.25 mL phosphate buffered saline incorporating 20 μCi of 3HTdR.
- Evaluation (hr after challenge):5 hours

Positive control substance(s):

other: α-hexylcinnamaldehyde formulated at a concentration of 25% in acetone / olive oil (4:1 v/v)

Results and discussion

Positive control results:

The positive control article produced a Stimulation Index of 4.49.

In vivo (LLNA)

Results

Results 1

Key result

Parameter:

SI

Variability:

599 +/- 196.1 DPM

Test group / Remarks:

Vehicle control

Remarks on result:

other: Control parameter

Results 2

Key result

Parameter:

SI

Value:

0.55

Variability:

330 +/- 138.7 DPM

Test group / Remarks:

10% in DMSO

Results 3

Key result

Parameter:

SI

Value:

1.22

Variability:

730 +/-565.8 DPM

Test group / Remarks:

25% in DMSO

Results 4

Key result

Parameter:

SI

Value:

0.67

Variability:

401 +/- 126.5 DPM

Test group / Remarks:

50% in DMSO

Results 5

Key result

Parameter:

SI

Value:

4.49

Variability:

2693 +/- 1860.1 DPM

Test group / Remarks:

Positive control

Any other information on results incl. tables

Individual DPMs and Stimulation Index (SI)

Concentration (%w/v) in DMSO	Group number	Animal number	DPM/ animal	Mean DPM/animal (Standard Deviation)	Stimulation Index (SI)^a
Vehicle	1	49	506	599 (± 196.1)	NA
		50	509
		51	941
		52	458
		53	583
10	2	54	146	330 (± 138.7)	0.55
		55	313
		56	421
		57	265
		58	504
25	3	59	711	730 (± 565.8)	1.22
		60	790
		61	186
		62	328
		63	1635
50	4	64	389	401 (± 126.5)	0.67
		65	285
		66	521
		67	540
		68	272
Positive control	5	69	1308	2693 (± 1860.1)	4.49
		70	1715
		71	1619
		72	3013
		73	5809

Key

DMSO    dimethyl sulphoxide

NA = Not applicable

^a= Stimulation Index of 3.0 or greater indicates a positive result

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Migrated information

Conclusions:

The Local Lymph Node Assay demonstrated that Potassium Allophonate does not have the potential to cause skin sensitisation.
The test article did not meet the criteria for classification as a sensitiser according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS).