Isobutyl methacrylate

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: Test procedure in accordance to national standard methods. Not GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: "Appraisal of the safety of chemicals in foods, drugs and cosmetics," by the Staff of the Division of Pharmacology, FDA, (1959)

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Isobutyl methacrylate

EC Number:

202-613-0

EC Name:

Isobutyl methacrylate

Cas Number:

97-86-9

Molecular formula:

C8H14O2

IUPAC Name:

isobutyl methacrylate

Specific details on test material used for the study:

Isobutyl methacrylate; clear, colorless, undiluted liquid, supplied by Röhm GmbH & Co KG, Darmstadt. Purity not specified, but typically > 99%

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Single dose

Doses:

The dose groups were 10, 12.6,  15.9 and 20 ml/kg which corresponded to 8880, 11189, 14119 and 17760  
mg/kg (with specific gravity = 0.888 g/ml).

No. of animals per sex per dose:

5/sex/dose

Details on study design:

Clinical findings  were recorded 20 minutes, 1, 3 and 24 hours, and 7 and 14 days after  dosing. A gross necropsy 
was performed on all animals found dead or at the end of the 14 day observation period. 

Statistics:

The LD50 was determined using  the calculation method of Litchfield and Wilcoxon.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

9 590 mg/kg bw

Remarks on result:

other: originally reported as 10.8 ml/kg

Mortality:

All deaths occurred within the first 48 hours post-administration. 

Clinical signs:

other: The clinical signs observed  within the first 24 hours included a generally reduced activity,  staggering gait and ataxia,  decreased tonus in muscles of extremities and  abdomen, diarrhea, piloerection, discoloration of the mucosa and   decreased body te

Gross pathology:

 Deceased animals showed hemorrhage  of the mucosa of the stomach and intestines.

Applicant's summary and conclusion

Interpretation of results:

practically nontoxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In a valid guideline study the oral LD50 of the test substance in rats was 9590 mg/kg bw.

Executive summary:

In a study following an FDA guideline from 1959, which is equivalent to an OECD 401 guideline study, i-BMA was administered at doses ranging from 8880 to17760 mg/kg by intragastric intubation to fasted male and female rats. Except for local effects at the site of first contact, haemorrhage in the intestinal tract, no target organ was identified. The LD50 was determined to be 9590 mg/kg, when administered as a single oral dose.