Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Well documented and reported study fully adequate for assessment. The study was conducted according to internationally accepted technical guidelines and in compliance with GLP in a recognized contract research organization.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report date:
2010

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Version / remarks:
of 1987
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method B.3 (Acute Toxicity (Dermal))
Version / remarks:
of 2008
Deviations:
no
Qualifier:
according to guideline
Guideline:
EPA OPPTS 870.1200 (Acute Dermal Toxicity)
Version / remarks:
of 1998
Deviations:
no
Qualifier:
according to guideline
Guideline:
other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), Test Data for Registration of Agricultural Chemicals, Acute dermal toxicity (2-1-2), 12 Nohsan No. 8147, Agricultural Production Bureau, November 24, 2000.
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Test type:
standard acute method
Limit test:
yes

Test material

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Sprague Dawley rats, strain: Crl:CD(SD) with appropriate range of bodyweight at study start.
- Source: Charles River (UK) Ltd.
- Age on the day of dosing (Day 1): 8 to 12 weeks.
- Weight on Day 1 (prior to dosing): Males: minimum 351 g, maximum 366 g,
Females: minimum 235 g, maximum 240 g.
- Housing Inside a barriered rodent facility in solid floor polycarbonate cages with a stainless steel mesh lid:
Day before dosing until Day 9: Individually.
Remainder of acclimation & post dose periods: In groups of 5 by sex.

- Bedding material: Autoclaved woodflakes.
- Cage enrichment: Chew block + plastic shelter
- Diet (ad libitum): Standard rodent diet (Rat and Mouse No. 1 Maintenance Diet)
without antibiotic, chemotherapeutic or prophylactic agent.
- Water (ad libitum): Pottable drinking water from the public supply.
- Acclimation period: 6 days before dosing.

Routine analysis of the batch of diet used, water and chew blocks did not provide evidence of contamination that might have prejudiced the study.
ENVIRONMENTAL CONDITIONS

Air conditioned room kept at positve pressure without re-circulation of the filtered fresh air supplied to the room.
Controlled environment, environmental conditions were set at:
- Temperature (°C): 21 ± 2°C
- Relative Humidity (%): 40 to 70%
- Photoperiod (artificial lighting): 12 hrs day / 12 hrs night
Deviations from these target ranges were not reported.

Administration / exposure

Type of coverage:
occlusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
TEST SITE
- Preparation: On the day before exposure the dorso-lumbar region clipped free of hair using veterinary clippers.
- Area of treated skin: Ca. 50 mm x 50 mm corresponding to approx. 10% of total body surface.
- Type of wrap used: Porous gauze, held in place with non-irritating dressing, further covered with waterproof dressing encircled firmly around the trunk of the animal.

REMOVAL OF TEST SUBSTANCE
Occlusive treatment of the clipped, intact skin lasted 24 hours. Then the dressings were removed, the treated area of skin washed with acetone, rinsed with warm water (30 - 40°C) and blotted dry with absorbent paper, to remove any residual test substance.

TEST MATERIAL AND DOSE PREPARATION
- Administered Dose: 2000 mg/kg bw administered as unchanged test substance (no vehicle used).
- Dose volume: 2.15 mL per kg body weight (specific gravity of the unchanged test substance = 0.930)

RATIONALE FOR DOSE SELECTED:
Pronounced acute dermal toxicity was not expected. Starting at the limit dose of 2000 mg/kg, in retrospect, proved to be appropriate, as no animals died at this dose.
Duration of exposure:
24 hours
Doses:
2000 mg/kg bw (5 males + 5 females)
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following the end of the 24-hour treatment period: 14 days
- Frequency of observations and weighing:
Deaths and overt signs of toxicity: Frequently after dosing on Day 1 and subsequently twice daily (morning and afternoon) until termination on Day 15
Skin reactions (detailed in Table 1): After removal of the dressings once daily for 14 days (Day 2 to Day 15).
Weighing of each animal: Day 1 (prior to application for dose calculation) and on Days 8 and 15.
- Necropsy performed: Yes, of all animals.

Statistics:
Statistical analysis is nappropriate for this study, as there were no deaths and only one dose group.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: No deaths at the limit dose of 2000 mg/kg.
Mortality:
There were no premature deaths.
Clinical signs:
Brown staining on the head in four females and urine staining in the perigenital area in one female were first noted on Day 2 (the day after dosing) and had completely resolved in all animals by Day 10.
Dermal reactions noted were erythema very slight in degree in two females and very slight to well defined in degree in a further female having resolved in the former two females by days 3 and 4 and in the latter female by Day 9. In the latter female, the erythema finding was followed by exfoliation/desquamation confined to Day 9. From Day 10 to the end of the study all animals were entirely free from any local or systemic clinical signs.
Body weight:
Body weight of the male dose group adequately increased throughout the study period. Marginal bodyweight loss (-1.6%) in one female animal during post-exposure observation week 2 and lower than normal body weight gain in a further 2 females during week 1 or 2 were reported, but by the toxicologist preparing the present robust study summary were considered not to represent an adverse effect.
Gross pathology:
Necropsy of each animal did not reveal any macroscopic pathologic abnormalities at termination of the study.

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU