3,5,5-trimethylhexanal

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October 1996 until April 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3,5,5-trimethylhexanal

EC Number:

226-603-0

EC Name:

3,5,5-trimethylhexanal

Cas Number:

5435-64-3

Molecular formula:

C9H18O

IUPAC Name:

3,5,5-trimethylhexanal

Details on test material:

Date of production: February/March 1996
Expiry date: March 1997
Properties: clear, colourless, liquid, visually homogenous
Stability: > 1 year
ph: not determinate
Purity: 91,2 mass % (gaschromatographic analysis)

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Wistar (HsdCpb: WU/SPF) rat
200 - 300 g body weight; weight variation did not exceed +/- 20 % of the mean body weight
Housing: Makrolon type III cage, each cabe containing one rat
Acclimization: Animals were acclimatized for at least 5 days.
Room temperature: 22 +/- 3 ° C
Relative humidity: 30 - 70 %
Light: Arificial light, from 7.00 a.m. to 7.00 p.m.
Bedding: soft wood

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

The undiluted liquid test substance (2.44 cm³/kg bodyweight) was applied by spreading it evenly over the prepared skin.
The treated area (approximately 50 x 50 mm) was then promplty covered with gauze which was held in place with a semiocclusive dressing
encircled firmly around the trunk. At the end of the 24 hours exposure period, the dressing was carefully removed and the treated area of
skin was cleaned with corn oil and absorbent paper.

Duration of exposure:

24 h

Doses:

single dermal application of 2.44 cm³/kg bodyweight

No. of animals per sex per dose:

5 male, 5 female

Control animals:

no

Details on study design:

Approximately 24 h before treatment hair was removed from the dorsolumbar region of each rat with electric clippers exposing an area equivalent to approximately 10 % of the total body surface.

Initially two males and two females were given a single dermal application of the test substance at a dose level of 2000 mg/kg bodyweight. Since no mortalities occured within 24 h p.a., further three male and three female rats were treated in the same way.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

There were no deaths following a single dermal application of TRIMETHYLHEXANAL at 2000 mg/kg bodyweight.

Clinical signs:

other: There were no signs of related systemic toxicity.

Gross pathology:

No macroscopic abnormalities were observed for animals killed on day 14.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

The acute lethal dermal dose (LD50) to rats of TRIMETHYLHEXANAL was found to be greater than 2000 mg/kg bodyweight.

Executive summary:

A study (limit-test) was performed to assess the acute dermal toxicity of TRIMETHYLHEXANAL to the rat. A group of ten rats (five male and five females) was given a single dermal application of the test substance at a dose level of 2000 mg/kg bodyweight. The treated area was covered for 24 h with gauze which was held in place by a semiocclusive dressing. All animals were killed and examined macroscopically on day 14, the end of the observation period.

There were not deaths and no signs of systemic reaction to treatment.

After removal of the dressings 24 h post applicationem (p.a.) until the end of the observation period no skin irritation were noted.

The male rats achieved satisfactory bodyweight gains throughout the study, whereas the female rats showed only minimal or no body weight gains. This effect is not considered to be substance related because variation of bodyweight in this age/bodyweight range in female rats is a physiological finding.

No abnormalities were recorded at the macroscopic examination on day 14.

The acute lethal dermal dose to male and female rats of TRIMETHYLHEXANAL was found to be > 2000 mg/kg.