Epoxy Resin T1800

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:

March to may 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study by a laboratory having a GLP certificate

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Certificate on january 27th 2009

Type of assay:

bacterial reverse mutation assay

Test material

Reference

Name:

Unnamed

Type:

Constituent

Method

Target gene:

The objective of the study was to evaluate the potential of the test item EPOXY RESIN T1800 (batch No 81016) to induce reverse mutation in Salmonella typhimurium.

Species / strain

Species / strain / cell type:

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

Additional strain / cell type characteristics:

DNA polymerase A deficient

Metabolic activation:

with and without

Metabolic activation system:

S9 mix

Test concentrations with justification for top dose:

The test item was freely soluble in the vehicle (DMSO) at 100 mg/mL.
Consequently, with a treatment volume of 50 µL/plate, the dose-levels were 10, 100, 500, 1000, 2500 and 5000 µg/plate

Results and discussion

Test results

Species / strain:

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

Metabolic activation:

with and without

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

The number of revertants for the vehicle and positive controls was as specified in the acceptance criteria. The study was therefore considered as valid.

Since the test item was freely soluble and non-toxic in the preliminary test, the highest dose-level retained for the main experiments was 5000 µg/plate, according to the criteria specified in the international guidelines.

The selected treatment-levels were: 312.5, 625, 1250, 2500 and 5000 µg/plate for both mutagenicity experiments with and without S9 mix.

No precipitate was observed in the Petri plates when scoring the revertants at any of the tested dose-levels.

No noteworthy toxicity was noted towards the tester strains used, either with or without S9 mix.

A slight increase in the number of revertants (2.6-fold the vehicle control value) was noted in the TA 1537 strain in the first experiment with S9 mix (direct plate incorporation method).This increase did not reach the threshold value of 3-fold the vehicle control value but was dose-related. In the second experiment performed using the preincubation method, a noteworthy (up to 4.1-fold the vehicle control value) increase in the number of revertants was observed. Since this increase exceeded the threshold of positivity and was dose-related, it was considered as biologically relevant.

Noteworthy increases in the number of revertants were noted in the TA 102 strain in both mutagenicity experiments with S9 mix. Since these increases exceeded the threshold value of 2- fold the vehicle control value and since they were reproducible, they were considered as biologically relevant.

Noteworthy increases in the number of revertants were noted in the TA 1535, TA 98 and TA 100 strains in both mutagenicity experiments with and without S9 mix. Since these increases exceeded the threshold value of positivity (3-fold the vehicle control value for the TA 1535 and 2‑fold the vehicle control value for the TA 98 and TA 100 strains) and since they were reproducible and generally dose-related, they were considered as biologically relevant.

Conclusion

Under our experimental conditions, the test item EPOXY RESIN T1800 (batch No. 81016) showed mutagenic activity in the bacterial reverse mutation test with Salmonella typhimurium, in presence and in absence of a rat metabolizing system.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
ambiguous

Under our experimental conditions, the test item EPOXY RESIN T1800 (batch No. 81016) showed mutagenic activity in the bacterial reverse mutation test with Salmonella typhimurium, in presence and in absence of a rat metabolizing system.