Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2017-06-12 to 2017-07-04
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
The test for acute dermal toxicity is performed on the rat. Although several mammalian species may be used, the rat is the preferred rodent species.
In the assessment and evaluation of the toxic characteristics of chemicals, the determination of acute dermal toxicity is useful where exposure by the dermal route is likely.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

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: particulate/powder

Test animals

Species:
rat
Strain:
Wistar
Remarks:
Crl: WI(Han)
Sex:
male/female
Details on test animals and environmental conditions:
Test animals:
Source: Charles River, 97633 Sulzfeld, Germany
Sex: male and female (non-pregnant and nulliparous)
Number of animals: 5 male and 5 female animals
Age at the beginning of the study: males: 11-12 weeks; females: 12-13 weeks
Body weight on the day of administration:Males: 276g - 304g; Females: 218g - 230g

Housing and Feeding Conditions:
- Full barrier in an air-conditioned room
- Temperature: 22 ± 3 °C
- Relative humidity: 55 ± 10%
- Artificial light, sequence being 12 hours light, 12 hours dark
- Air change: 10 x / hour
- Free access to Altromin 1324 maintenance diet for rats and mice
- Free access to tap water, sulphur acidified to a pH value of approximately 2.8 (drinking water, municipal residue control, microbiological controls at regular intervals)
- The animals were kept individually in IVC cages, type III H, polysulphone cages on Altromin saw fibre bedding
- Adequate acclimatisation period (at least five days) under laboratory conditions

Administration / exposure

Type of coverage:
occlusive
Vehicle:
water
Details on dermal exposure:
Preparation of the Animals:
- The animals were marked individualy by tail painting
- Approx. 24 hours before the test, the fur was removed from the dorsal area of the trunk using an electric clipper. Only animals with healthy intact skin were used
- Prior to the application a detailed clinical observation was performed on all animals. Only healthy animals were used.

Application:
- The test item was applied at a single dose, uniformly over an area which was approximately 10% of the total body surface
- The test item was held in contact with the skin by a dressing throughout a 24-hour period. The dressing consisted of a gauze-dressing and non-irritating tape and was fixed with an additional dressing in a suitable manner

Dose Level:
- The test item was applied at a single dose of 2000 mg/kg body weight to each animal

Exposure Period:
- The test item was held in contact with the skin throughout a 24-hour period. At the end of the exposure period the residual test item was removed using aqua ad injectionem



Duration of exposure:
24 h
Doses:
a single dose of 2000 mg/kg bw
No. of animals per sex per dose:
5 males and 5 females
Control animals:
no
Details on study design:
Observation Period:
- All animals were observed for 14 days after dosing

Evaluation of Primary Skin Irritation:
- Signs of erythema and oedema were assessed using the scoring system laid down in OECD Guideline 404

Weight Assessment:
The animals were weighed on day 1 (prior to the application) and on days 8 and 15

Clinical Examination:
- A careful clinical examination was made several times on the day of dosing (at least once during the first 30 minutes and with special attention given during the first 4 hours post-dose)
- As soon as symptoms were noticed they were recorded
- Thereafter the animals were observed for clinical signs once daily until the end of the observation period. All abnormalities were recorded
- Cageside observations included changes in the skin and fur, eyes and mucous membranes. Also respiratory, circulatory, autonomic and central nervous systems and somatomotor activity and behaviour pattern were examined. Attention was directed to observations of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma

Pathology:
- At the end of the observation period the animals were sacrificed with an overdosage of pentobarbital injected intraperitoneally at a dosage of 250-400 mg/kg bw
- All animals were subjected to gross necropsy and examined macroscopically for gross pathological changes
- In absence of gross pathological changes no tissues were preserved for a possible histopathological evaluation

Evaluation of Results:
- Individual reactions of each animal were recorded at each time of observation
- Toxic response data were recorded by sex and dose level
- Nature, severity and duration of clinical observations were described
- The body weight changes were summarised in a tabular form
- Necropsy findings were described



Statistics:
not specified

Results and discussion

Preliminary study:
not applicable
Effect levelsopen allclose all
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: skin irritation reported
Sex:
male
Dose descriptor:
other: dose
Effect level:
2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: no mortality
Sex:
female
Dose descriptor:
other: dose
Effect level:
2 000 mg/kg bw
Based on:
test mat.
Remarks on result:
other: no mortality
Mortality:
The test item showed no mortality
Clinical signs:
No signs of systemic toxicity. Signs of local toxicity and irritation.
Body weight:
- A slight weight loss was recorded for 3 out of 10 animals during the two weeks of observation
- 1 out of 5 males showed unchanged weight during the first week
-1 out of 5 females showed unchanged weight during the first week
-1 out of 5 females showed unchanged weight during first and second week
- All other animals showed weight gain during first and second week

The effects on weight development might be secondary to the dressing, and toxicological relevance of this finding cannot clearly be concluded.
Gross pathology:
No specific gross pathological changes were recorded for any animal
Other findings:
- Erythema grade 1 was observed in all male animals but no female animals
- Crust was observed in 4 of 5 male and all female animals
- Necrosis was observed in 3 of 5 male animals but in no female animals
- Necrosis was not reversible within the observation period

Any other information on results incl. tables

Absolute body weights in g and body weight gain in %

Animal No. / Sex body weight gain (g) %
Day 1 Day 8 Day 15 Day 1-15
21/Male 286 271 307 7
22/Male 304 315 349 15
23/Male 279 295 327 17
24/Male 276 283 304 10
25/Male 287 291 316 10
26/Female 219 216 215 -2
27/Female 218 224 230 6
28/Female 229 227 245 7
29/Female 230 240 240 4
30/Female 223 224 230 3

The effects on weight loss are a common observation for animals within this study type, mainly for female animals and might be secondary to the dressing, and toxicological relevance of this finding cannot clearly be concluded.

 LD50Cut-Off

Dose (mg/kg bw)

Number of Animals

Number of Intercurrent Deaths

LD50Cut-Off (mg/kg bw)

2000

5 males

0

> 2000

2000

5 females

0

> 2000

bw = body weight

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The dermal lethal dose of the test item after a single dermal administration to female rats, observed over a period of 14 days is: LD50 cut-off (rat) > 2000 mg/kg bw.
Executive summary:

In order to determine the potential acute dermal toxicity of the test item, an acute dermal study on the rat was performed according to OECD 402 and in compliance to GLP. Wistar rats (5 male and 5 female) were exposed for 24h to 2000 mg/kg bw test substance.

Single dermal application of the test item to rats at a dose of 2000 mg/kg body weight was not associated with mortality but with signs of local toxicity and irritation were observed. Although weight loss effects were observed, especially with female animals, it is concluded that this is a common observation for this study type and that this is probably secondary to the dressing. Toxicological relevance of this finding cannot be clearly concluded.

In conclusion, the dermal LD50was determined to be > 2000 mg/kg body weight.