Reaction Mass of Didodecyl nonylphenyl phosphite and Dodecyl bis(4-nonylphenyl) phosphite and 4-nonylphenyl ditridecyl phosphite and Bis(4-nonylphenyl) tridecyl

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

In vitro bacterial gene mutation assay (Ames Test) (comparable to OECD 471)

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

May 26, 1983

Deviations:

not specified

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

TEST MATERIAL NAME (as stated in study report): TK 12437 (Irgastab CH 302)

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Sponsor; Batch No. 08520495
- Expiration date of the lot/batch: July, 1996
- Purity: within the product specifications

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

S9 fraction from livers of Aroclor 1254 treated rats

Test concentrations with justification for top dose:

Preliminary Toxicity / Range-Finding Test (TA 100 and WP2): 20 to 5000 µg/plate.
Mutagenicity Test: Original experiment - 625 - 5000 µg/plate; Confirmatory experiment - 78 - 625 µg/plate. Doses in original experiment were chosen based on results of range-finding test. Because toxic effects occurred on the growth of revertant colonies in the original experiment with strain TA 100 (without and with activation) and with strain TA 1537 (with activation) the experiments with these strains were repeated with four concentrations in the ränge of 78.1 - 62 5 µg/plate

Vehicle / solvent:

DMSO

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

9-aminoacridine

2-nitrofluorene

sodium azide

cyclophosphamide

other: 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: about 48 hours at 37 ± 1.5°C in darkness

NUMBER OF REPLICATIONS: two plates per test concentration

Rationale for test conditions:

per standard references, including OECD 471 test guideline

Evaluation criteria:

Assay acceptance criteria:
A test is considered acceptable if the mean colony counts of the control values of all strains are within the acceptable ranges and if the results of the positive controls meet the criteria for a positive response.

Criteria for a positive response:
The test substance is considered to be mutagenic in this test system if:
- A positive effect is observed in one strain and the effect can be reproduced in a confirmatory experiment.
- A positive effect is observed in two or more strains.

A positive effect is defined as an increase of the mean number of revertants per plate for any concentration above that of the negative control by at least a factor of 2,0 with strains TA 98, TA 1535, TA 1537 and WP2 uvrA, or by a factor of at least 1.5 with strain TA 100. Generally a concentration-related effect should be demonstrable.

Species / strain:

bacteria, other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Conclusions:

In a standard Ames Test, Irgastab CH 302 did not induce gene mutations in bacteria with our without metabolic activation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Justification for classification or non-classification

Based on the available data, Irgastab CH 302 is not classified for germ cell mutagenicity according to Regulation (EC) No 1272/2008.