Pentaerythritol, ethoxylated, esters with acrylic acid

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

The substance is negative in the Ames test. The substance showed a positive response in the mouse lymphoma TK assay. The colony sizing indicated clastogenic effects. However, these effects were not confirmed in the in vivo micronucleus assay.

Link to relevant study records

Reference

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:

November 2006-February 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to OECD guideline No. 471 and under GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Target gene:

histidine gene in Salmonella typhimurium

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S9 mix

Test concentrations with justification for top dose:

In the first experiment (toxicity testing): 3, 10, 33, 100, 333 , 1000, 2500 and 5000 µg/plate.
In the second experiment :33, 100, 333 , 1000, 2500 and 5000 µg/plate.

Vehicle / solvent:

DMSO

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: sodium azide for TA 1535 and TA 100; 4-nitro-o-phenylene-diamine for TA 1537 and TA 98, methyl methane sulfonate for TA 102: 2-aminoanthracene for all strains in the presence of metabolic activation.

Details on test system and experimental conditions:

Two independent experiments were performed both with and without liver microsomal activation. The first experiment was conducted to evaluate the toxicity of the test substance in all strains with 8 concentrations ranging from 3 to 5000 µg/plate, using the plate incorporation test. The second experiment was conducted using a pre-incubation assay with 6 concentrations ranging from 33 to 5000 µg/plate.

Concentrations of the test chemical which are overtly toxic are easily visualized as showing no bacterial growth on the plate (i.e. absence of background lawn). Lower levels of toxicity may be seen as a thin or sparse bacterial lawn, a reduction in the number of revertants, or the appearance of microcolonies (overgrown background lawn). Positive and negative controls were run concurrently with the test chemical, and appropriate responses for these controls are prerequesites for evaluating the response of the bacteria to the test chemical.

Evaluation criteria:

The Salmonella typhimurium reverse mutation assay is considered acceptable if it meets the following criteria:
- regular background growth in the negative and solvent control
- the spontaneous reversion rates in the negative and solvent control are in the range of the historical control data of the laboratory
- the positive control substances should producer a significant increase in mutant colony frequencies

Statistics:

According to OECD guideline No. 471, a statistical analyis of the data is not mandatory.

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

A reduced background growth was observed from 2500 to 5000 µg/plate with and without metabolic activation in the first experiment and with metabolic activation in the second experiment. No toxic effects, evident as a reduction in the number of revertants, occurred in the test groups with and without metabolic activation.

No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with the test substance at any concentration level, neither in the presence nor absence of metabolic activation. There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally accepted border of biological relevance.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results (migrated information):
negative

It can be stated that under the experimental conditions reported, the test substance did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used. Therefore, the test substance is considered to be non-mutagenic in the Salmonella typhimuirum reverse mutation assay.

Executive summary:

The study was performed to investigate the potential of the test substance to induce gen mutations according to the plate incorporation test (experiment I) and the pre-incubation test (experiment II) using the Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and TA 102. The assays were performed both with and without liver microsomal activation.

The test substance was tested at the following concentrations:

Experiment I: 3, 10, 33, 100, 333, 1000, 2500 and 5000 µ/gplate

Experiment II: 33, 100, 333, 100, 2500 and 5000 µg/plate

Reduced background growth was observed from 2500 to 5000 µ/gplate with and without metabolic activation in experiment I and with metabolic activation in experiment II. No toxic effects, evident as a reduction in the number of revertants, occurred in the test groups with and without metabolic activation.

No substantial increase in revertant colony numbers of any of the tester strains was observed following treatment with the test substances at any dose level, neither in the presence nor absence of metabolic activation (S9 mix). There was also no tendency og higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological significance.

Appropriate reference mutagens were used as positive controls and showed a distinct increase of induced revertant colonies.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Two in vitro mutagencity assays (Ames test and mouse lymphoma gene mutation test) and an in vivo micronucleus assay are available for the test substance. The substance is negative in the Ames test, with and without metabolic activation. The substance showed a positive response in the mouse lymphoma TK assay, both in the absence and presence of metabolic activation. The colony sizing indicated clastogenic effects. However, these effects were not confirmed in the in vivo micronucleus assay. There is no reason to believe that the negative results would not be relevant to humans.

Justification for selection of genetic toxicity endpoint
Two in vitro mutagenticity tests and one in vivo mutagenicity test are available.

Justification for classification or non-classification

The test substance is negative in the Ames test, in the in vitro HPRT assay and in the in vivo micronucleus assay. Therefore, the substance does not need to be classified and labelled as a mutagen, according to the Regulation 1271/2008 and the Directive 67/548/EEC.