Tetrakis(2-butoxyethyl) orthosilicate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 January to 7 February 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Tetrakis(2-butoxyethyl) orthosilicate

EC Number:

242-560-0

EC Name:

Tetrakis(2-butoxyethyl) orthosilicate

Cas Number:

18765-38-3

Molecular formula:

C24H52O8Si

IUPAC Name:

tetrakis(2-butoxyethyl) orthosilicate

Test animals

Species:

rat

Strain:

other: Bor: WISW (SPF cpb)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Fa. Winkelmann
- Age at study initiation: 6-8 weeks
- Weight at study initiation:200-300 g
- Fasting period before study: None
- Diet: Ad libitum.
- Water: Ad libitum
- Acclimation period: Five days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20± 3
- Humidity (%): 30-70
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- % coverage: 10% of body surface was shaved.
- Type of wrap if used: Semi-occlusive


REMOVAL OF TEST SUBSTANCE
- Time after start of exposure: Patch removed after 24 hours.


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2.07 cm3/kg bw
- Constant volume or concentration used: yes

Duration of exposure:

24 hours

Doses:

One limit dose of 2000 mg/kg bw

No. of animals per sex per dose:

Five

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations for clinical signs: 0.5, 1, 2, 3, 4, 5 and 6 hours, and then daily up to two weeks post-exposure.
- Necropsy of survivors performed: yes
- Other examinations performed: Body weights recorded on the day of exposure and on day 7. Macroscopy changes were recorded following sacrifice on day 14.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No deaths occurred.

Clinical signs:

No clinical signs

Body weight:

Normal weight gain

Gross pathology:

No changes to skin and subcutaneous tissues. Two males and one female had swollen and red stomach mucosa glands, and sometimes reddening of the small bowel mucosa.

Other findings:

No other findings.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of a good quality OECD 402 study that was conducted to GLP, the dermal LD50 was greater than 2000 mg/kg bw in male and female rats as no deaths occurred.

Executive summary:

In an OECD 402 study, conducted to GLP, 2000 mg/kg bw test material was applied under a semi-occlusive dressing for 24 hours on the shaved, intact skin of five male and five female rats. Animals were observed for two weeks following removal of the patch, and body weights recorded. All animals were subject to necropsy and examined macroscopically. No deaths or clinical signs were observed in any of the animals. Body weight gains were not affected by treatment. There were no changes to skin and subcutaneous tissues. Two males and one female had swollen and red stomach mucosa glands, and sometimes reddening of the small bowel mucosa. The dermal LD₅₀ in rats is therefore >2000 mg/kg bw.