Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
27 January 1997 to 18 April 1997
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997
Report Date:
1997

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
other: Animal Welfare Act of 1966 (P.L. 89-544), as amended in 1970, 1976, and 1985. Code of Federal Regulations, Title 9 [Animals and Animal Products], Subchapter A - Animal Welfare Parts 1, 2, and 3.
Deviations:
no
Qualifier:
according to
Guideline:
other: Guide for the Care and Use of Laboratory Animals, Institute of Laboratory Animal Resources, Commission on Life Sciences, National Research Council, National Academy Press, Washington, D.C, 1996.
Deviations:
no
GLP compliance:
yes
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Test material form:
liquid
Details on test material:
Appearance: Amber liquid
Storage: Room temperature

Test animals

Species:
rat
Strain:
other: CrLCDBR
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Females nulliparous and non-pregnant: Yes
- Age at study initiation: Males were approximately 8 weeks old and Females were approximately 9 weeks old.
- Weight at study initiation: Males weighed 247 to 272 grams and Females weighed 208 to 228 grams.
- Housing: Single housed in suspended stainless steel and wire mesh cages, with absorbent paper below cages. during the study period.
- Diet: Ad libitum
- Water: Ad libitum; the availability of water was checked at lease once daily for all animals.
- Acclimation period: 7 days; animals were examined for viability at least once daily.
More animals than required for the conduct of the study were purchased and acclimated. Animals determined to be unsuitable for inclusion on the study because of poor health, outlying body weight, or other abnormalities were excluded from selection by the Study Director and/or technical staff. Study animals were selected from the remaining animals using a computer-generated, body weight sorting program. Weight variation for individual animals was within ±20 % of the mean body weight of their sex. The animals subsequently were examined by the attending veterinarian.

ENVIRONMENTAL CONDITIONS
Monitored continuously:
- Temperature (°C): 64 to 72 degrees Fahrenheit (17.8 - 22.2 °C)
- Humidity (%): 30 to 70 percent relative humidity
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): Approximately 12 hours light (0700 to 1900) and 12 hours dark (1900 to 0700) by automatic timer.

IN-LIFE DATES: From: To: 11 February 1997 to 25 February 1997.

Administration / exposure

Type of coverage:
occlusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
TEST SITE
- Area of exposure: Approximately 24 hours prior to topical administration of the test material, the hair of each rat in the area of the dorsal surface from the shoulder region to the lumbar region was closely clipped with an electric clipper. The skin was left intact. Animals were reclipped as needed to facilitate dermal evaluations.
- % coverage: Not less than 10 % of the body surface.
- Type of wrap if used: An 8 ply, 5 cm x 10 cm gauze patch secured with non-irritating tape. To retard evaporation, to prevent ingestion of the test material and to keep the substance in contact with the skin, the gauze patch was secured to the trunk of the animal with an occlusive covering held in place by Elastoplast.

REMOVAL OF TEST SUBSTANCE
- Washing: Residual test material was removed using peanut oil and paper towels.
- Time after start of exposure: After approximately 24 hours of exposure.

TEST MATERIAL
- Amount applied: 2.13 ml/kg (2000 mg/kg)
- Constant volume or concentration used: Yes

Duration of exposure:
24 hours
Doses:
2000 mg/kg of body weight
No. of animals per sex per dose:
5 animals per sex per dose
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were examined for viability twice daily Monday through Friday, and once daily on weekends and holidays (if applicable).
Clinical observations were made as to the nature, onset, severity, and duration of toxicological signs at 1, 2, 4, and 6 hours after dosing, and daily thereafter for a total of 14 days.
Body weights were recorded once prior to initiation of dosing for allocation purposes, and on Days 0, 7, and 14.
Dermal responses were evaluated on Days 1 (approximately 45 minutes after patch removal), 3, 7, 10, and 14.
- Necropsy of survivors performed: Yes. after completion of the 14-day observations, all animals were weightd and sacrificed by exsanguination following carbon dioxide asphyxiation. A gross necropsy was performed on all animals. The necropsy examination included examination of the external surface of the body, and the cranial, thoracic, and abdominal cavities and their contents.
Statistics:
Statistical analyses included means and standard deviations of body weights and body weight change by group and sex.

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
no indication of skin irritation up to the relevant limit dose level
Mortality:
All animals survived to scheduled study termination on Day 14.
Clinical signs:
All animals were free of clinical signs of toxicity throughout the study.
Body weight:
All animals gained weight over their initial (Day 0) values during the study.
Gross pathology:
All animals were free of gross postmortem abnormalities.
Other findings:
Topical application of the test material elicited dermal irritation in nine of the ten animals. On Day 1, very slight erythema was observed in two males and one female. The incidence of erythema increased and on Day 3, very slight erythema was observed in three males and three females and well-defined erythema was observed in two females. Oedema was very slight in three females on Day 3. All animals were free of erythema and oedema on Days 7, 10 and 14.
Desquamation was observed in four males and five females on Day 3, in four males and four females on Day 7 and in one male and two females on Day 10. All animals were free of desquamation on Day 14.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
Under the conditions of the study, the LD50 has been determined to be greater than 2000 mg/kg bw in the rat.
Executive summary:

A study was conducted to investigate the acute dermal toxicity of the test material in accordance with the standardised guideline OECD 402 under GLP conditions.

The acute dermal toxicity of the test material was evaluated following its application to the clipped backs often Crl:CDBR rats. A limit dose of 2000 mg/kg of the test material was applied to not less than 10 % of the body surface, covered with a gauze patch, and secured with non-irritating tape. The gauze patch was secured to the trunk of the animal with an occlusive covering held in place by Elastoplast to retard evaporation, to prevent ingestion of the test material, and to keep the substance in contact with the skin. After approximately 24 hours of exposure, the plastic sleeve and gauze patch were removed. Clinical observations were performed 1, 2, 4, and 6 hours after dosing, and once per day thereafter for a total of 14 days. Dermal responses were evaluated on Days 1 (approximately 45 minutes after patch removal), 3, 7, 10, and 14 according to the Draize method (Draize, 1959). Body weights were recorded on the day prior to dosing, on the day of dosing (Day 0), and on Days 7 and 14.

All animals survived to scheduled study termination on Day 14, were free of clinical signs or postmortem abnormalities, and gained weight over their initial (Day 0) values. Dermal irritation, initially observed in three animals on Day 1, was most pronounced on Day 3 when slight erythema was observed in three males and three females, and well-defined erythema was observed in two females. Slight oedema was only observed on Day 3 in three females. All animals were free of erythema and edema on Day 7. Desquamation, observed in nine often animals on Day 3, persisted in three animals on Day 10.

Dermal application of the test material at a limit dose of 2000 mg/kg did not produce any treatment related mortality or overt signs of toxicity under the conditions of this study. Transient dermal irritation was the only finding observed. Under the conditions of the study, the LD50 has been determined to be greater than 2000 mg/kg bw in the rat.