Bis[(2-ethyl-1-oxohexyl)oxy]dioctylstannane

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted on read-across material

Justification for type of information:

Read-across to structurally similar substance dioctyltin oxide (Public name: DOTO, CAS: 870-08-6, EC: 212-791-1), see attached justification.

Cross-reference

Reason / purpose for cross-reference:

read-across source

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

13 June 2012 to 27 June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

other: read-across target

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system 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: 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

IN-LIFE DATES: From 13 June 2012 to 27 June 2012

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.

Key result

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.

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

Interpretation of results:

other: Not classified in accordance with EU Criteria

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 accordance with standardised guidelines OECD 402 and EU Method B.3, under GLP conditions.

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.

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Bis[(2-ethyl-1-oxohexyl)oxy]dioctylstannane

EC Number:

246-325-3

EC Name:

Bis[(2-ethyl-1-oxohexyl)oxy]dioctylstannane

Cas Number:

24577-34-2

Molecular formula:

C32H64O4Sn

IUPAC Name:

[(2-ethylhexanoyl)oxy]dioctylstannyl 2-ethylhexanoate

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.