Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Study Start 7th September 2006 - Study Report 16th February 2007
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

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
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid
Specific details on test material used for the study:
Identity Witconate P-1460
Description Light brown paste
Batch number 2140-5901
Activity 88.8 %
Stability of test item Stable under storage conditions.
Expiry date V 07-APR-2007
Stability of test item dilution Unknown in water; excluded from the statement of
compliance.
Storage conditions At room temperature (range of 20 1: 5 °C), light protected.

Test animals

Species:
rat
Strain:
Wistar
Remarks:
HanRcc:WIST (SPF)
Sex:
male/female
Details on test animals and environmental conditions:
Number of animals per group: 5 males and 5 females
Total number of animals: 5 males and 5 females
Age when treated: Males: 8 weeks, Females: 11 weeks
Identification: By unique cage number and corresponding color-coded spots on the tail. The animals were marked at acclimatization start.
Randomization: Selected by hand at time of delivery. No computer generated randomization program.
Acclimatization: Under laboratory conditions, after health examination. Only animals without any visible signs of illness were used for the study

HUSBANDRY

Conditions: air changes per hour, and continuously monitored environment with ranges for room temperature 22 +/- 3 °C and for relative humidity between 30-70 % (values above 70 %during cleaning process possible), automatically controlled light cycle of 12 hours light and 12 hours dark, music during the daytime light period.

Accommodation: During acclimatization in groups of five per sex in Makrolon type-4 cages with standard softwood bedding. Individually in Makrolon type-3 cages with standard softwood bedding
("Lignocel", SchillAG, CH-4132 Muttenz) during treatment and observation.

Diet: Pelleted standard Provimi Kliba 3433 rat/mouse maintenance diet, batch no. 36/06 (Provimi Kliba AG, CH-4303 Kaiseraugst/ Switzerland) ad libitum. Results of analyses for contaminants are archived at RCC Ltd.

Water: Community tap water from FülIinsdorf ad Iibitum. Results of bacteriological, chemical and contaminant analyses are archived at RCC Ltd.

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
water
Remarks:
Purified water prepared at RCC Ltd (deionised water which was processed and treated by the PURELAB Option-R unit. This latter links four purification technologies: reverse osmosis, adsorption, ion-exchange and photo oxidation).
Details on dermal exposure:
Dose Formulation

The dose levels are in terms of the test item as supplied by the sponsor. The test item was weighed into a tared glass beaker on a suitable precision balance and the vehicle added (weight:volume). The formulation was prepared shortly before the application using a magnetic stirrer, a spatula and an Ultra-Turrax (Janke & Kunkel, D-79219 Staufen) as homogenizers. Homogeneity of the test item in the vehicle was maintained during administration using a magnetic stirrer.

TREATMENT
One day before treatment, the backs of the animals were clipped with an electric clipper, exposing an area of approximately 10 % of the total body surface.

Only those animals without injury or irritation on the skin were used in the test.

On test day 1, the test item was applied at a dose of 2000 mglkg body weight evenly on the intact skin with a syringe and covered with a semi-occlusive dressing. The dressing was wrapped around the abdomen and fixed with an elastic adhesive bandage.

Application volume/kg body weight: 6 mL

Twenty-four hours after the application the dressing was removed and the skin was flushed with lukewarm tap water and dried with disposable paper towels. Thereafter, the reaction sites were assessed.

The fur of all animals was shaved on test days 5 and 12 just after the assessment of the reaction to facilitate the skin reading for the next day.

Rationale: Dermal administration was used as this is one possible route of human exposure during manufacture, handling and use of the test item.

Duration of exposure:
14 days with termination on day 15.
Doses:
On test day 1, the test item was applied at a limit dose of 2000 mg/kg body weight evenly on the intact skin.
No. of animals per sex per dose:
Single limit dose group of 5 males and 5 females.
Control animals:
not required
Details on study design:
On test day 1, the test item was applied at a dose of 2000 mglkg body weight evenly on the intact skin with a syringe and covered with a semi-occlusive dressing. The dressing was wrapped around the abdomen and fixed with an elastic adhesive bandage. Application volume/kg body weight: 6 mL

Mortality/Viability: Daily during the acclimatization period, during the first 30 minutes and at approximately 1, 2, 3 and 5 hours after administration on test day 1 (with the clinical signs) and twice
daily during days 2-15.

Bodyweights: On test days 1 (prior to administration), 8 and 15.

Clinical signs: Daily during the acclimatization period, during the first 30 minutes and at approximately 1, 2, 3 and 5 hours after administration on test day 1. Once daily during days 2—15. All abnormalities were recorded.

Local signs: Once daily during days 2-15. All abnormalities were recorded.

NECROPSY
All animals were killed at the end of the observation period by Carbon dioxide asphyxiation and discarded after macroscopic examinations were performed. No organs or tissues were retained.
Statistics:
No statistical analysis was used as this was a sinlge dose level, limit dose study.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
act. ingr.
Mortality:
No deaths occurred during the study.
Clinical signs:
No systemic signs of toxicity were observed during the study period.

The test item induced local changes at the application site. A moderate erythema was noted in all animals on test day 2 after removal of the dressing and persisted as moderate or slight for at least three days, up to day 7—12 or up to the end of the observation period.

Slight or moderate scab formation was observed in all animals for at least one day between days 3 and 10 of the study. For one male and one female scabs were still present at the application site at the end of the observation period (day 15).

Slight scaling of the skin was observed in all animals except one female. This was observed for 4 to 9 days between days 4 and 11 of the study.

A brown patchy discoloration of the application site was noted in four out of the five treated females from day 3 up to day 7—9. In addition, slight oedema of the treated skin was observed in two females on day 3 and 3—4, respectively.

One treated male showed slight fissures at the application site on day 3 and again on days 8—9 and the same was noted for one female on days 8-15 of the study.

On day 15, at the end of the observation period, four males and four females had completely recovered from the local symptoms whereas one male and one female still expressed sins of local damage.
Body weight:
The body weight of the animals was within the range commonly recorded for this strain and age with the exception of male animal No. 4, which lost 3.2% of body weight during the last week of observation.
Gross pathology:
No macroscopic findings were observed at necropsy.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The median lethal dose of Witconate P-1460 after single dermal administration to rats of both sexes, observed over a period of 14 days is:
LD50 (rat):greater than 2000 mglkg body weight.

There were no indications of systemic toxic effects in any of the rats at the 2000 mg/kg limit dose. Therefore the test substance is not classified under EU CLP as the dermal LD50 is greater than category 4 (>2000mg/kg bodyweight). Based on the lack of any systemic toxicity at this dose, it is concluded that there is unlikely to be an LD50 less than 5000mg/kg so GHS criteria even for category 5 for acute dermal toxicity would not apply in regions where this has been adopted outside the EU.
Executive summary:

RESULTS

Five male and five female Hacc:W|ST (SPF) rats were treated with Witconate P-1460 at 2000 mg/kg by dermal application. The test item was diluted in vehicle (purified water) at a concentration of 0.33 glmL and administered at a volume dosage of 6 mL/kg. The application period was 24 hours.

The animals were examined daily during the acclimatization period and mortality, viability and clinical signs were recorded. All animals were examined for clinical signs at approximately 30 minutes, 1, 2, 3 and 5 hours after treatment on day 1 and once daily during test days 2-15. Local signs were noted once daily from test day 2 to 15. Mortality/viability was recorded at approximately 30 minutes, 1, 2, 3 and 5 hours after administration on test day 1 (with the clinical signs) and twice daily during days 2-15. Body weights were recorded on day1 (prior to administration) and on days8 and 15. All animals were necropsied and examined macroscopically.

No deaths occurred during the study.

No clinical signs of toxicity were observed during the course of the study.

Local signs of irritation were noted at the application site of the animals. These includederythema, scabs, scaling, oedema, fissures and brown patchy discoloration. The local findings were reversible in four males and four females whereas one male and one male still expressed local symptoms at the end of the observation period.

The body weight of the animals was within the range commonly recorded for this strain and age.

No macroscopic findings were observed at necropsy.

CONCLUSION

The median lethal dose of Witconate P-1460 after single dermal administration to rats of both sexes, observed over a period of 14 days is:

LD50 (rat):greater than 2000 mglkg body weight