Isobutyl methacrylate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

DATA QUALITY: The study was conducted in accordance with a recognized international scientific procedure and followed the test protocol and procedures of Ames (1975). Complete study results were presented supporting the conclusions that isobutyl methacrylate was not mutagenic in this test system. Full description of the test material was provided. No data regarding GLP.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1987

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

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; CAS: 97-86-9; purity 98 %; supplied by EastmanChemical Co.

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Details on mammalian cell type (if applicable):

Strains obtained from Ames, University of California, Berkely

Additional strain / cell type characteristics:

other:  obtained from Dr. B.N. Ames.

Metabolic activation:

with and without

Metabolic activation system:

The S-9 fractions of Aroclor 1254-induced, male  Sprague-Dawley rats and male Syrina Hamster livers were prepared  immediately prior to use. The S-9 mixes contained 10 % S-9. 

Test concentrations with justification for top dose:

0, 100, 333, 1000 and 10000 ug/plate
5 concentrations plus a control were  evaluated in triplicate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO

Controls

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other:  With metabolic activation: 2-Aminoanthracene: with all strains; without metabolic activation:   Sodium azide: TA100 and TA1535, 4-Nitro-o-phenylenediamine: TA98,  9-Aminoacridine: TA1537

Details on test system and experimental conditions:

The test followed a pre-incubation protocol. The test  material, Salmonella culture, and S-9 mix or buffer were 
incubated at 37  degrees C, without shaking, for 20 minutes. The top agar was added, and  the contents of the 
tubes mixed and poured onto the surface of  Vogel-Bonner medium in a petri dish. The histidine-revertant 
colonies on  these plates were counted after 2 days of incubation at 37 degrees C. A  preliminary cytotoxicity 
assays was conducted using TA100 to determine  the appropriate dose range. Once determine, the test doses 
were performed  in triplicate, repeated one week following the initial trial. A maximum  of 0.5 ml of solvent was 
added to each plate. Concurrent solvent and  positive controls in the presence or absence of S-9 were performed. 

Evaluation criteria:

A  positive response was demonstrated when a reproducible dose-related  increase over the corresponding solvent 
control was seen, and it was  judged weakly positive if a low-level dose response was seen.

Results and discussion

Test results

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Additional information on results:

The results were obtained from testing in Salmonella typhimurium strains  TA98, TA100, TA1535 and TA1537, without S9, 
with hamster liver S9 (HLI)  and with rat liver S9 (RLI) demonstrated there was no increase in his+  revertants in any strain 
or at any dose. The positive controls gave the  expected increase in his+ revertants compared to the solvent control. The  
test material was negative for mutagenicity in this assay.  No significant increases in the number of revertant colonies were  
observed at doses which also resulted in cytotoxicity.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Test material was not mutagenic in any of the S. typhimurium strains tested, with or without hamster or rat
liver S-9 activation.

Executive summary:

In a a valid guideline study, the test material was not mutagenic in any of the S. typhimurium strains tested, with or without hamster or rat liver S-9 activation.