Ammonium carbamate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in accordance with OECD Guideline for Testing of Chemicals 404 and GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ammonium carbamate

EC Number:

214-185-2

EC Name:

Ammonium carbamate

Cas Number:

1111-78-0

Molecular formula:

CH3NO2.H3N

IUPAC Name:

ammonium carbamate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Individual 0.5-g doses of the test substance were ground to a fine powder and weighed into tared weigh boats that were covered, labeled, and transported to the animal room for dosing. Sufficient deionized water (prepared on-site) was dispensed for moistening the test substance.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Rabbits were obtained from Covance Research Products, Inc., Denver, PA. The animals were acclimated to laboratory conditions for a minimum of 4 months. During this period, each animal was observed twice daily for mortality and changes in general appearance or behavior.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

water

Remarks:

deionized

Amount / concentration applied:

0.5-g-doses moistened with approx. 0.05 mL of deionized water were applied to an area of skin approx. 2.5x2.5 cm.

Duration of treatment / exposure:

Initially, a single animal was selected and treated with the test substance in order to minimize unnecessary use of additional rabbits where the test substance is shown to be severely irritating or corrosive. This animal was exposed to the test substance for 3 minutes, 1 hour, and 4 hours under semi-occlusive dressings. At the end of the exposures, the bandages were removed and the sites wiped with disposable paper towels moistened with deionized water. No irritation was observed in this animal following any exposure. Based on these results, and to complete the study, 2 additional rabbits received single, 4-hour, semi-occluded exposures of the test substance.

Observation period:

3-minute application site: evaluated immediately after patch removal and 1 hour later.
1-hour application site: evaluated immediately after patch removal and approx. 24, 48 and 72 hours later

Number of animals:

3

Details on study design:

MORTALITY:
The rabbits were observed twice daily, once in the morning and once in the afternoon, for mortality and moribundity. All animals received detailed physical examinations on the day of dosing prior to dosing and these data are maintained in the study records.
CALCULATION OF PRIMARY DERMAL IRRITATION INDEX:
The Primary Dermal Irritation Index was calculated from scores recorded at 30-60 minutes and at 24, 48, and 72 hours after patch removal for the 4-hour exposure test sites. The mean scores for erythema and edema were calculated separately to the nearest tenth and added together.
BODY WEIGHTS:
Body weights were obtained and recorded on study day 0 (initiation) and at each rabbit’s termination from the study (study day 3).
TERMINATION:
After study termination, the rabbits were euthanized by intravenous injection of sodium pentobarbital and discarded.

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: all time points

Score:

0

Irritant / corrosive response data:

No signs of dermal irritation were noted during the study. The Primary Irritation Index (PII) was 0.0.

Other effects:

There were no deaths and no remarkable body weight changes noted during the study. Two of the 3 males had slight body weight losses from study day 0 to study day 3; however, slight body weight fluctuations are commonly observed in rabbits on a restricted diet.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

No signs of dermal irritation were noted during the study. A classification according to Regulation (EC) No 1272/2008 is not required.

Executive summary:

The objective of this study was to determine the irritative potential of the ammonium carbamate following a single, semi-occluded exposure to the skin of albino rabbits. The study was conducted according to GLP and OECD guideline 404.

Initially, a single animal was dosed to evaluate the irritative potential of the test substance. This single rabbit received 3 applications of the test substance applied concurrently for 3 minutes, 1 hour, and 4 hours. Each 0.5-g dose of the test substance was moistened with deionized water and applied to the clipped, unabraded skin. At the completion of all exposures, the bandages were removed and the sites washed. No irritation was observed in this animal following any exposure. Based on these results, and to complete the study, 2 additional rabbits received single 4-hour exposures of the test substance. Application sites were evaluated in accordance with the method of Draize. Skin reactions for the 3-minute test site were evaluated immediately after patch removal and 1 hour later. Skin reactions for the 1-hour test site were evaluated immediately after patch removal and at approximately 24, 48, and 72 hours after removal of the 4-hour patch. Skin reactions for the 4-hour test sites were evaluated at approximately 30-60 minutes and 24, 48, and 72 hours after patch removal.

There were no deaths and no remarkable body weight changes during the study. No signs of dermal irritation were noted during the study. Based on these results, the test substance is considered to be not irritating. A classification according to Regulation (EC) No 1272/2008 is not warranted.