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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2017
Reliability:
1 (reliable without restriction)
Qualifier:
according to guideline
Guideline:
OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)
Deviations:
no
GLP compliance:
yes
Test type:
fixed dose procedure
Limit test:
no
Specific details on test material used for the study:
The test substance is identified as Isobutyl isobutyrate. The purity is 98.99%. The physical state/appearance of material is clear colourless liquidwhite solid. The expiry date of material is 6 February 2018. The substance can be stored at room temperature in the dark conditions.
Species:
rat
Strain:
Wistar
Sex:
female
Details on test animals or test system and environmental conditions:
Female Wistar (RccHanTM :WIST) strain rats were supplied by Envigo RMS (UK) Limited, Oxon, UK.The females were nulliparous and non-pregnant. After an acclimatization period of at least 5 days the animals were selected at random and given a number unique within the study by indelible ink-marking on the tail and a number written on a cage card. At the start of the study the animals were 8 to 12 weeks of age. The body weight variation did not exceed of the mean body weight at the start of treatment.
The temperature and relative humidity were set to achieve limits of 19 to 25 o c and 30 to 70% respectively. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.
Route of administration:
oral: gavage
Vehicle:
not specified
Details on oral exposure:
All animals were dosed once only by gavage, using a metal cannula attached to a graduated syringe. The volume administered to each animal was calculated according to the fasted body weight at the time of dosing. Treatment of animals was sequential. Sufficient time was allowed between each dose group to confirm the survival of the previously dosed animals.
Doses:
2000 mg/kg
No. of animals per sex per dose:
A total of five animals were therefore treated at a dose level of 2000 mg/kg in the study.
Details on study design:
All animals were dosed once only by gavage, using a metal cannula attached to a graduated syringe. The volume administered to each animal was calculated according to the fasted body weight at the time of dosing. Treatment of animals was sequential. Sufficient time was allowed between each dose group to confirm the survival of the previously dosed animals. Clinical observations were made 30 minutes, 1, 2, and 4 hours after dosing and then daily for 14 days. Morbidity and mortality checks were made twice daily, early and late during normal working days, and once daily at weekends and public holidays. Individual body weights were recorded on Day 0 (the day of dosing) and on Days 7 and 14. At the end of the observation period the animals were killed by cervical dislocation. 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
Sex:
female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
There were no deaths
Clinical signs:
other: There were no cllinical observations.
Gross pathology:
No abnormalities were noted at necropsy.
Interpretation of results:
other: Globally Harmonized Classification System — Unclassified
Conclusions:
The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System — Unclassified).
Executive summary:

The study was performed to assess the acute oral toxicity of the Isobutyl isobutyrate in the Wistar strain rat.

In the absence of toxicity at a dose level of 2000 mg/kg in one animals, an additional group of animals was treated with 2000 mg/kg dose level. A total of five animals were therefore treated at a dose level of 2000 mg/kg in the study. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy. There were no deaths observed during the test. There were no signs of systemic toxicity. All animals showed expected gains in body weight. No abnormalities were noted at necropsy.The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight (Globally Harmonized Classification System — Unclassified).

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
2 000 mg/kg bw

Acute toxicity: via inhalation route

Link to relevant study records
Reference
Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Justification for type of information:
The study was conducted well before GLP or OECD guidelines. Documentation is very limited, but the study was conducted at a leading laboratory to the state of the art at the time.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
GLP compliance:
no
Test type:
other:
Limit test:
no
Species:
rat
Route of administration:
inhalation: vapour
Type of inhalation exposure:
whole body
Duration of exposure:
6 h
Concentrations:
3.88 or 31.94 mg/l
No. of animals per sex per dose:
3
Control animals:
no
Details on study design:
Test subjects were exposed to either 3.88 or 31.94 mg/l for 6 hours and then monitored for 2 weeks.
Dose descriptor:
LC50
Effect level:
> 3.88 - < 39.14 mg/L air
Based on:
test mat.
Mortality:
2/3 dead at 39.14 mg/l, no deaths at 3.88 mg/l
Interpretation of results:
GHS criteria not met
Conclusions:
There were 2/3 dead at 39.14 mg/l, no animals were found dead at 3.88 mg/l.
Executive summary:

The LC50 was between 3.88 and 39.14 mg/l.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed

Acute toxicity: via dermal route

Link to relevant study records
Reference
Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Justification for type of information:
The study was conducted well before GLP or OECD guidelines. Documentation is very limited, but the study was conducted at a leading laboratory to the state of the art at the time.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
GLP compliance:
no
Test type:
other:
Limit test:
no
Species:
guinea pig
Type of coverage:
occlusive
Details on dermal exposure:
IBIB was applied to skin under a gauze pad and occlusive covering with a rubber cuff.
Duration of exposure:
24 hours
Doses:
5 or 10 cc/kg
Details on study design:
The test article was applied for 24 hours under an occlusive rubber cuff. After removal the test subjects were observed for 2 weeks.
Dose descriptor:
LD50
Effect level:
> 10 other: cc/kg
Based on:
test mat.
Mortality:
none
Interpretation of results:
GHS criteria not met
Conclusions:
The dermal LD50 was > 10 cc/kg
Executive summary:

The dermal LD50 was > 10 cc/kg

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
10 000 mg/kg bw

Additional information

Justification for classification or non-classification

Classification is not appropriate as an LD50 was not reached in either oral or dermal toxicity testing

One supporting acute oral study and one key acute oral study following OECD TG 420 under GLP conditions were available for isobutyl isobutyrate (IBIB). In supporting study, the rats were dosed at concentrations ranging from 200 to 12,800 mg/kg and monitored for 2 weeks. The LD50 was determined between 6400 and 12800 mg/kg. In the key study, rats were treated with 2000 mg/kg dose level. There were no deaths observed during the test. There were no signs of systemic toxicity. All animals showed expected gains in body weight. No abnormalities were noted at necropsy. The acute oral median lethal dose (LD50) of the test item in the female Wistar strain rat was estimated to be greater than 2000 mg/kg body weight. Similarly, in an acute dermal study, no mortality was observed when guinea pigs were treated with IBIB dermally. Inhalation (2 reliability) study gave LC50 value between 3.88 and 39.14 mg/l in rats. IBIB is not classified under Globally Harmonized Classification System (Unclassified) in acute studies.