Nitriles, C16-18

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

28 Sep 1988 - 13 Oct 1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Read-across from structural identical substance with same chain length distribution but with some level of unsaturation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Tallownitrile

IUPAC Name:

Tallownitrile

Details on test material:

Name: Talgnitril (Tallownitrile)
Talgfettsäurenitril (Tallow fatty acid nitrile)
Purity: approx. 99%
Impurity: < 0.5% fatty acid amide
Apearance: Light yellow liquid
melting point: -3 ºC
boiling point: 270 ºC
Molecular weight: approx. 255
Specific gracvity: 0.83
Date of submission: Oct. 21, 1987
Storage condition: dark at 22 ºC

Method

Target gene:

- S. typhimurium: Histidine gene
- E. coli: Tryptophan gene

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Species / strain 3

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Sprague-Dawley rat liver S9-mix induced by Aroclor 1254 (500 mg/kgbw) 5 days before sacrifice.

Test concentrations with justification for top dose:

Three plates / dose
Experiment 1:
All tester strains (without and with S9) : 0, 4, 20, 100, 500, 2500 and 10000 μg/plate
Visible precipitation was observed at all concentrations of 500 µg/plate and above.
Experiment 2:
All tester strains (without and with S9) : 0, 4, 20, 100, 500, 2500 and 10000 μg/plate
Visible precipitation was observed at all concentrations of 500 µg/plate and above.

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Accepted and approved by authorities and international guidelines

Controls

Controls 1

Positive controls:

yes

Positive control substance:

other: Sodium-azide 1 µg/plate (TA100, TA1535); 2-Nitrofluorene 2.5µg/plate (TA98, TA1538); 9-Aminoacridine 50µg/plate (TA1537); MNNG 2.5µg/plate (WP2uvrA)

Remarks:

Without metabolic activation

Controls 2

Positive controls:

yes

Positive control substance:

other: 2-Aminoanthracen 0.5 µg/plate (TA100, TA1538, TA98), 1 µg/plate (TA1535, TA1537), 10 µg/plate (WP2uvrA); Benzo[a]pyrene 10 µg/plate (all strains)

Remarks:

With metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)
DURATION
- Exposure duration: 48 to 72 hours at 37 deg.C in the dark
NUMBER OF REPLICATIONS:
- Doses of the test substance were tested in triplicate in each strain. Two independent experiments were conducted.
NUMBER OF CELLS EVALUATED: The suitable amount of bacteria in the cell suspension is checked by nephelometry.
DETERMINATION OF CYTOTOXICITY
- In all tester strains a reduced rate of spontaneously occurring colonies as well as visible thinning of bacterial lawn were used as indicator for Toxicity. Thinning of the bacterial lawn was controlled microscopically.
- In combination with the second experiment, toxicity testing was performed as follows: 0.1 ml of the different dilutions of the test compound were thoroughly mixed with 0.1 ml of the 10-6 dilution of the overnight culture of TA100 and plate with histidine and biotin rich top agar (3 plates per dose). The solvent control is compared with the number of colonies per plate in the presence of the test compound. Results are given as a ratio of these values (= surviving fraction)
OTHER EXAMINATIONS:
- The presence of precipitation of the test compound on the plates was determined.
- Sterility S-9 Mix and the test compound was indicated by the absence of contamination on the test material and S-9 Mix sterility check plates. Control

Evaluation criteria:

Not indicated. Evaluated for significant increase of the number of revertant colonies in any of the tester strains in absence or presence of S-9 mix.

Statistics:

Not indicated.

Results and discussion

Test results

Species / strain:

other: all

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Remarks:

up to max concentration (10000 µg/plate)

Vehicle controls validity:

not applicable

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
-Precipitation: precipitation was observed at dose levels of 500 μg/plate and above with and without S-9 Mix.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

The negative and strain-specific positive control values indicate that the test conditions were adequate and that the metabolic activation system functioned properly.
It is concluded that this test is valid and that Tallownitrile is not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.

Executive summary:

Talgnitril was tested for mutagenicity with the strains TA 100, TA 1535, TA 1537, TA 1538, TA 98 of Salmonella typhimurium and Escherichia coli WP2uvrA.

 

The mutagenicity studies were conducted in the absence and inthepresence of a metabolizing system derived from rat liver homogenate. A dose range of 5 different doses from 4 microgram/plate to 5 000 microgram/plate was used.

 

Control plates without mutagen showed that the number of spontaneous revertant colonies was similar to that described in the literature. All the positive control compounds gave the expected increase in the number of revertant colonies.

 

Toxicity: The test compound proved to be not toxic to the bacterial strains.5 000microgram/plate was chosen as top dose level for the mutagenicity study.

 

Mutagenicity: In the absence of the metabolic activation system the test compound did not show a dose dependent increaseinthe number of revertants in any of the bacterial strains. Also in the presence of a metabolic activation system, treatment of the cells with Talgnitril did not result in relevant increases in the number of revertant colonies.

 

Summarizing. it can be stated that Talgnitril is not mutagenic in these bacterial test systems either with or without exogenous metabolic activation at the dose levels investigated.