1,3-dimethylurea

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets scientific standards with acceptable restrictions (occlusive exposure for 24 hours).

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Reference 2

Reference Type:

publication

Title:

OECD SIDS 1,3-Dimethylurea (CAS: 96-31-1)

Author:

BASF AG

Year:

2003

Bibliographic source:

UNEP Publications

Report date:

2003

Materials and methods

Principles of method if other than guideline:

Method: according Fed. Reg., 38, 187, § 1500.41, (27.09.1973)
Skin irritation was tested using an internal standard method (BASF test). White Vienna rabbits were used. Usually, animals were treated for 1, 5 and 15 minutes and for 20 hours using occlusive conditions. An application site of 2.5 X 2.5 cm was covered with the liquid or powdered and moistened test substance.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

1,3-dimethylurea

EC Number:

202-498-7

EC Name:

1,3-dimethylurea

Cas Number:

96-31-1

Molecular formula:

C3H8N2O

IUPAC Name:

1,3-dimethylurea

Details on test material:

- Name of test material (as cited in study report): N,N'-Dimethylurea; N,N'-Dimethylharnstoff
- Substance number: 77/21
- Physical state: cristalline
- Analytical purity: 97.5 %
- Impurities (identity and concentrations): minor components: ca. 1 % monomethylurea; ca. 1 % trimethylurea and 0.5 % water

Test animals

Species:

rabbit

Strain:

Vienna White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: breeder: M. Gaukler, Offenbach
- Age at study initiation: no data
- Mean weight at study initiation: ca. 2.87 kg
- Housing: no data
- Diet (e.g. ad libitum): Ssniff K, standard diet for rabbits and guinea pigs, Intermast GmbH, Soest, Germany, ad libitum
- Water (e.g. ad libitum): water, adlibitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- no data

Test system

Type of coverage:

occlusive

Preparation of test site:

other: clipping

Vehicle:

water

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): approximately 0.5 g
- Concentration (if solution): 80 % aqueous preparation

Duration of treatment / exposure:

24 hour(s)

Observation period:

8 days

Number of animals:

3 males; 3 females

Details on study design:

TEST SITE
- Area of exposure: dorsal clipped skin
- Application: The test patch was covered with the substance preparation and applied to the skin.
- coverage: ca. 2.5 x 2.5 cm
- Type of wrap if used: Test patches were covered with a gummed linen cloth (5 x 5 cm), fixed with a thin adhesive tape and wraped with a gauze bandage.
During exposure, the animals were fixed and do not obtain neither feed nor water.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): no data

SCORING SYSTEM: according to the Draize scoring system, at 24 and 72 hours and on day 8.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: 24 and 72 hours

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 8 days

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

other: 24 and 72 hours

Score:

0

Max. score:

4

Reversibility:

other: no effects

Irritant / corrosive response data:

On intact skin, 2/6 animals showed very slight erythema, which was completely reversible within 8 days (mean Draize scores: 24 hr - 0.3; 72 hr - 0.2).
Edema was not observed at any time.

Other effects:

No toxic signs.

Any other information on results incl. tables

Table 1 Skin irritation
Animal	Reading	Erythema	Edema	Additional findings
1	24 h	1	0	-
2	24 h	1	0	-
3	24 h	0	0	-
4	24 h	0	0	-
5	24 h	0	0	-
6	24 h	0	0	-
1	72 h	0	0	-
2	72 h	1	0	-
3	72 h	0	0	-
4	72 h	0	0	-
5	72 h	0	0	-
6	72 h	0	0	-
1	8 days	0	0	-
2	8 days	0	0	-
3	8 days	0	0	-
4	8 days	0	0	-
5	8 days	0	0	-
6	8 days	0	0	-
mean animal 1	24, 72 h	0.50	0.00
mean animal 2	24, 72 h	1.00	0.00
mean animal 3	24, 72 h	0.00	0.00
mean animal 4	24, 72 h	0.00	0.00
mean animal 5	24, 72 h	0.00	0.00
mean animal 6	24, 72 h	0.00	0.00
mean all animals	24, 72 h	0.33	0.00

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU