2,4,4-trimethylpentene

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant, guideline study, available as unpublished report, no restrictions, fully adequate for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

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:

2,4,4-trimethylpentene

EC Number:

246-690-9

EC Name:

2,4,4-trimethylpentene

Cas Number:

25167-70-8

Molecular formula:

C8H16

IUPAC Name:

2,4,4-trimethylpent-1-ene

Details on test material:

- Name of test material (as cited in study report): 2,4,4-trimethylpentene (also known as diisobutylene and diisobutene)
- Physical state: clear, colourless liquid
- Analytical purity: 95.19%
- Lot/batch No.: Batch No. 2 (a 50:50 mixture of two original batches of 2,4,4-trimethylpentene - the details of which are as follows: Batch No. R11 supplied by Shell and Batch No. 155833 supplied by Erdolchemie).
- Expiration date of the lot/batch: 29 April 1997
- Storage condition of test material: Under nitrogen, protected from light, in a cool store.

Test animals

Species:

rat

Strain:

other: CD (remote Sprague-Dawley origin)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Limited, Margate, Kent, England
- Age at study initiation: Approximately 5 weeks
- Weight at study initiation (day -1): 122-133 g (males); 118-134 g (females)
- Fasting period before study: overnight prior to dosing and 4 hours following dosing
- Housing: Stainless steel grid cages . Five animals of the same sex / cage.
- Diet: Complete pelleted rodent diet (RM1(E) SQC, from Special Diets Services Limited, Witham, Essex, England ad libitum except overnight prior to, and for 4 hours after, dosing.
- Water: Tap water ad libitum
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 18-28°C
- Humidity: 54-70%
- Air changes: At least 10/hr
- Photoperiod: 12 hrs dark / 12 hrs light

IN-LIFE DATES: From: 23 May 1996 To: 6 June 1996

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

maize oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: Prepared at the appropriate concentration in maize oil to permit administration at a constant volume-dosage of 10 mL/kg

Doses:

2000 mg/kg bodyweight

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations were recorded 3 times on day 1 and daily thereafter. Bodyweights were recorded on the day before dosing and on days 1,8 and 15
- Necropsy of survivors performed: yes

Statistics:

Not applicable (limit test, no mortalities)

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No mortalities

Clinical signs:

other: other: No abnormalities

Gross pathology:

There was a single case of hydronephrosis of the kidney

Applicant's summary and conclusion

Interpretation of results:

other: low oral toxicity

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

The acute oral median lethal dosage (LD50) of 2,4,4-trimethylpentene was greater than 2000 mg/kg. 2,4,4-Trimethyl pentene is considered to be of low oral toxicity.

Executive summary:

A group of 5 male and 5 female CD rats (fasted overnight) were dosed by gavage at 2000 mg/kg of 2,4,4 -TMP (in maize oil) and were observed daily for 14 days after dosing. Bodyweights were recorded weekly during the observation period. There were no mortalities and no signs of toxicity. All animals gained weight and there were no significant necropsy findings. The acute oral median lethal dosage (LD₅₀) of 2,4,4-trimethylpentene was greater than 2000 mg/kg. 2,4,4-trimethyl pentene is considered to be of low oral toxicity and does not require classification under DSD or CLP.