3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate homopolymer, uretdione type

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

Study period:

1985-03-05 to 1985-03-08

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions: Incomplete documentation, TA 102 or E.coli WP2 were not tested

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Principles of method if other than guideline:

Ames BN et al. (1975). Mutat. Res. 31, 347-364

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate homopolymer, uretdione type

EC Number:

938-351-5

Molecular formula:

residual C12H18N2O2, otherwise C24H36N4O4 (dimer) and higher species

IUPAC Name:

3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate homopolymer, uretdione type

Details on test material:

Isophorone diisocyanate oligomer (uretdione type) of Hüls AG, purity not reported

Method

Target gene:

mutated gene loci responsible for histidine auxotrophy

Species / strain

Species / strain / cell type:

other: Salmonella typhimurium TA 1535, TA 1537, TA 1538, TA 98, TA 100

Additional strain / cell type characteristics:

other: histidine auxotroph

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat S9 liver homogenate, male Wistar/TNO/W 74 rats,  enzymatic activity confirmed with aminoanthracene

Test concentrations with justification for top dose:

10 to 5000 µg/plate

Vehicle / solvent:

Acetone (CAS No. 67-64-1)

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: with metabolic activation: Aminoanthracene

Details on test system and experimental conditions:

SYSTEM OF TESTING
- Metabolic activation system:    Aroclor induced rat S9 liver homogenate, male Wistar/TNO/W 74 rats,  enzymatic activity confirmed with 
aminoanthracene
ADMINISTRATION: 
- Solvent: acetone (CAS No. 67-64-1)
- Number of replicates: 2
- Pre-incubation: with and without

Evaluation criteria:

CRITERIA FOR EVALUATING RESULTS: 
mutagenic effects (i.e  ratio of revertant rates treated/control >= 2)  at <= 5000 µg/plate with generally positive dose-response relationship in  any 
strain

Statistics:

no data

Results and discussion

Test results

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: not reported; probably not observed

Remarks on result:

other: other: Salmonella typhimurium TA 1535, TA 1537, TA 1538, TA 98, TA 100

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Under the conditions of the study the test item Isophorone diisocyanate cyclodimer proved to be non-mutagenic, both in the presence and in the
absence of Arochlor-induced liver microsomes, for all test strains used in this study.

Executive summary:

The substance Isophorone diisocyanate cyclodimer was tested in the Ames Salmonella mutagenicity test for any mutagenic activity. The test organisms were five histidine-auxotrophic Salmonella typhimurium strains (TA 1535; TA 1537; TA 1538; TA 98 and TA 100). Under the conditions of the study the test item Isophorone diisocyanate cyclodimer proved to be non-mutagenic, both in the presence and in the absence of Arochlor-induced liver microsomes, for all test strains used in this study.