Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
13 June 2012 - 27 June 2012
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The study was performed in compliance with GLP and in accordance with the standardised guidelines OECD 402 and EU Method B.3. The study was performed to a high standard sufficient to assess the quality of the presented results. Since the study was conducted on the read across substance, dioctyltin oxide, it has been assigned a reliability score of 2.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report Date:
2012

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
Details on test material:
- Name of test material (as cited in study report): Di-n-octyltin oxide
- Physical state: solid, white
- Storage condition of test material: room temperature in the dark

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: at lest 200 g (weight variation did not exceed ± 20 % of the mean weight for each sex).
- Housing: individually during 24 hour exposure period and in groups of five, by sex, for the remainder of the study in suspended solid-floor polypropylene cages.
- Diet: provided ad libitum
- Water: mains drinking water ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 25 ºC
- Humidity (%): 30 - 70 %
- Air changes (per hr): at least 15 changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours dark / 12 hours light

Administration / exposure

Type of coverage:
semiocclusive
Vehicle:
arachis oil
Details on dermal exposure:
TEST SITE
- Area of exposure: on the day before treatment the back and flanks of each animals were clipped free of hair
- % coverage: approximately 10% of the total body surface area
- Type of wrap if used: a piece of surgical gauze was placed over the treatment area and semi-occluded with a piece of self-adhesive bandage

REMOVAL OF TEST SUBSTANCE
- After the 24 hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with arachis oil BP to remove any residual test material

TEST MATERIAL
- the appropriate amount of test material was moistened with arachis oil BP and applied as evenly as possible to the area of shorn skin

Duration of exposure:
24 hours
Doses:
2000 mg/kg
No. of animals per sex per dose:
5 males and 5 females
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were observed to deaths and overt signs of toxicity 0.5, 1, 2 and 4 hours after dosing and once daily thereafter. The test site was observed daily for evidence of primary irritation and scored according to Draize (1977) (see table 1 in "Any other information on material and methods incl. tables). Individual bodyweights were recorded prior to application of the test material on day 0 and on days 7 and 14.
- Necropsy of survivors performed: Yes
- Other examinations performed: All animals were subjected to gross necropsy. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
There were no deaths.
Clinical signs:
There were no signs of systemic toxicity.
Body weight:
Animals showed expected gains in bodyweight over the study period, except for one male which showed bodyweight loss during the first week but expected gain in bodyweight during the second week.
Gross pathology:
No abnormalities were noted at necropsy.
Other findings:
There were no signs of dermal irritation.

Any other information on results incl. tables

Table 2: Individual Bodyweights and Weekly Bodyweight Changes

Animal no. and sex

Bodyweight (g) at day

Bodyweight change (g) during week

0

7

14

1

2

1M

309

314

328

5

14

2M

287

303

323

16

20

3M

282

305

332

23

27

4M

399

425

435

26

10

5M

367

358

380

-9

22

1F

202

204

214

2

10

2F

221

226

237

5

11

3F

217

220

232

3

12

4F

214

221

228

7

7

5F

201

202

217

1

15

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
Under the conditions of the study, the LD50 of the test material in the Wistar strain of rat was determined to be greater than 2000 mg/kg bw.
Executive summary:

The acute dermal toxicity of the test material was investigated in a GLP study which was conducted in accordance with standardised guidelines OECD 402 and EU Method B.3. During the study, a group of ten animals (five males and five females) was given a single, 24 -hour, semi-occluded dermal application of the test material to intact skin at a dose level of 2000 mg/kg bw. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy. Under the conditions of the study there were no deaths and no signs of systemic toxicity. Animals showed normal weight gains and there were no signs of dermal irritation. Furthermore, no abnormalities were noted at necropsy. The acute dermal median lethal dose (LD50) of the test material in the Wistar strain of rat was therefore determined to be greater than 2000 mg/kg bw.