Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2017-02-07 to 2017-02-22
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.3 (Acute Toxicity (Dermal))
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.1200 (Acute Dermal Toxicity)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
fixed dose procedure
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: stable

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: On dosing, weighed aliquots of this were moistened with the smallest amount of corn oil to ensure good skin contact

FORM AS APPLIED IN THE TEST (if different from that of starting material)
: solid. The supplied test item was ground to a powder. On dosing, weighed aliquots of this were moistened with the smallest amount of corn oil to ensure good skin contact.

Test animals

Species:
rat
Strain:
Sprague-Dawley
Remarks:
Hsd
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Envigo RMS srl (San Pietro al Natisone (UD), Italy)
- Females (if applicable) nulliparous and non-pregnant: yes ((nulliparous and non-pregnant)
- Age at study initiation: 6 to 8 weeks old
- Weight at study initiation: 176 to 200 grams (weight range at arrival 158.4 to 197.3 grams)
- Fasting period before study: No
- Housing: Clear polysulphone H-Temp solid bottomed cages (TecniplastGazzada S.a.r.l., Buguggiate, VA, Italy) measuring 42.5×26.6×18.5 cm during acclimatisation period and 42.5×26.6×18.5 cm during the study with nesting material provided into suitable bedding bags
- Diet (e.g. ad libitum): 4 RF 18 (Mucedola S.r.l., Via G. Galilei, 4, 20019, Settimo Milanese (MI) Italy) ad libitum
- Water (e.g. ad libitum): Drinking water supplied to each cage via a water bottle ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 °C ± 2°C
- Humidity (%): 55% ± 15%
- Air changes (per hr): Approximately 15 to 20 air changes per hour
- Photoperiod (hrs dark / hrs light): Artificial (fluorescent tubes), daily light/dark cycle of 12/12 hours

IN-LIFE DATES: From: 2017-02-01 To: 2017-02-22

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
corn oil
Remarks:
On dosing, weighed aliquots of this were moistened with the smallest amount of corn oil to ensure good skin contact
Details on dermal exposure:
TEST SITE
- Area of exposure: dorsal surfaces of the trunk of each animal
- % coverage: 10%
- Type of wrap if used: A patch of surgical gauze covered by a strip of synthetic film was placed over the treated site and the whole assembly held in place by encircling the trunk of the animal with a length of elastic adhesive bandage, this forming a semi-occlusive barrier.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): After exposure, the adhesive bandage and gauze patch were removed. The treatment area was cleaned by gentle swabbing of the skin with cotton wool soaked with lukewarm water.
- Time after start of exposure: The animals remained in contact with the test item for 24 hours.

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): Aliquots were weighed according to the body weight of each animal measured prior to dosing
- For solids, paste formed: yes (The supplied test item was ground to a powder. On dosing, weighed aliquots of this were moistened with the smallest amount of corn oil to ensure good skin contact).

VEHICLE
- Amount(s) applied (volume or weight with unit): test material moistened with small amounts of corn oil to ensure good contact.

Duration of exposure:
24h
Doses:
2000 mg/Kg (Once only, on the day of dosing (Day 1))
No. of animals per sex per dose:
5/sex/dose
Control animals:
not specified
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Mortality and morbidity - twice daily; Clinical signs: on dosing, approximately 1 hour and 20 minutes after dosing; approximately 2 hours after dosing; approximately 4 hours after dosing; and then once daily for 14 days; Body weight: at allocation to the study (Day -1), on the day of dosing (Day 1) andon Days 8 and 15
- Necropsy of survivors performed: yes (gross necropsy examination for both external andinternal abnormalities, with particular attention to the treatment site)
- Other examinations performed: clinical signs, body weight

Treatment area preparation:
On the day before dosing (Day –1), a single area was clipped free of hair (by an electric clipper equipped with a suitable blade) on the dorsal surfaces of the trunk of each animal (approximately 10% of body surface). Care was taken to avoid damage to the skin.

Dosing procedureAn aliquot of the supplied test item was spread evenly over an area of approximately 10% ofthe body surface. A patch of surgical gauze covered by a strip of synthetic film was placedover the treated site and the whole assembly held in place by encircling the trunk of theanimal with a length of elastic adhesive bandage, this forming a semi-occlusive barrier.

Termination
All animals were sacrificed on Day 15 using carbon dioxide narcosis.
Statistics:
The classification was based on Regulation (EC) No. 1272/2008 and subsequent revisions.

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
No mortality occurred during the study.
Clinical signs:
Slight to moderate scabs on the treatment site (dorsal region) were observed in several animals from Day 4. These had completely recovered by the end of the observation period in all animals, with the exception of three females, that showed scabs on the treatment site also on the day of necropsy.
Body weight:
Body weights and body weight changes were within the expected range for this species and age of animals at the end of the study.
Gross pathology:
No abnormalities were found at necropsy examination performed on all animals at termination of the study. Only scabs were observed at the treated site in three animals.

Any other information on results incl. tables

Table 1. Macroscopic observations - Group incidence

Number of Animals: 5

Number examined: 5

 

Males

Females

Treatment site

 

- Abnormal area(s)

-

3

- No abnormalities detected

5

2

 

Whole animal

 

- No abnormalities detected

5

2

Applicant's summary and conclusion

Interpretation of results:
other: Not classified according to the CLP Regulation
Conclusions:
The results observed in this study indicate that the test material has no toxic effects on the rat following dermal exposure over a 24 hour period at a dose level of 2000 mg/Kg. Based on the lack of mortality, the acute dermal LD50 was determined to be >2000 mg/Kg.
Executive summary:

In a key Guideline (OECD 402) acute dermal toxicity study, the test material was dermally administered to Sprague-Dawley rats (5/sex/dose) at a single dose of 2000 mg/Kg for a period of 24 hours under semi-occlusive conditions. Post exposure, the adhesive bandage and gauze patch were removed and the treated area (dorsal surface of the trunk of each anima) was cleaned by gentle swabbing of the skin with cotton wool soaked with lukewarm water. The animals were subsequently observed for a period of 14 days. On Day 15, all animals were sacrificed and subjected to gross necropsy examination for both external and internal abnormalities.

 

No mortality was observed through the study period. Slight to moderate scabs on the treatment site (dorsal region) were observed in several animals from Day 4. These had completely recovered by the end of the observation period in all animals,

with the exception of three females (nos. 1, 3, and 7), that showed scabs on the treatment site also on the day of necropsy.

 

The body weight changes observed during the study were within the expected range for this species and age of animals. No significant abnormalities were found at necropsy in the animals at termination. Scabs in three female animals (nos. 1, 3 and 7) were observed at the treated site.

 

These results indicate that the test material has no toxic effects on the rat following dermal exposure over a 24 hour period at a dose level of 2000 mg/Kg. Based on the lack of mortality, the acute dermal LD50 was determined to be >2000 mg/Kg.