Fatty acids, C16-18 and C18-unsatd., branched and linear

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:

06 Feb 1996 - 16 Feb 1996

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions, only four strains tested.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

adopted May 23, 1983

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted December, 1992

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Isooctadecanoic acid

EC Number:

250-178-0

EC Name:

Isooctadecanoic acid

Cas Number:

30399-84-9

IUPAC Name:

16-methylheptadecanoic acid

Details on test material:

- Name of test material (as cited in study report): Prisorine 3505
- Physical state: liquid
- Analytical purity: not indicated by sponsor; treated as 100 % pure
- Lot/batch No.: N541439
- Stability under test conditions: stable
- Storage condition of test material: at room temperature in the dark
- Other: pale yellow

Method

Target gene:

his operon

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

rat liver microsomal enzymes from adult male Wistar rats (S9-mix) obtained from Aroclor 1254-induced animals.

Test concentrations with justification for top dose:

3, 10, 33, 100, 333, 1000, 3330, 5000 μg/plate (range finder)
3, 10, 33, 100, 333, 1000, 3330 μg/plate (main study)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

Saline, DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: -S9-mix: sodium azide(1 µg/plate), 9-aminoacridine (60 µg/plate), daunomycine (4 µg/plate), methylmethanesulfonate (650 µg/plate); +S9-mix: 2-aminoanthracene (0.5 and 5 µg/plate)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in top agar (plate incorporation)

DURATION
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: triplicate in two experiments

Evaluation criteria:

A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in any tester strain at any concentration is not greater than two times the solvent control value, with or without metabolic activation.
b) The neagtive response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) It reduces at least 2-fold, dose related increase in the number of revertants with respect tot he number induced by the solvent control in any of the tester strains, either with or without metabolic activation. However, any mean plate count of less than 20 is considered to be not significant.
b) The positive response should be reproducible in at least one independently repeated experiment.

Results and discussion

Test results

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: Prisorine 3505 precipitated in the top agar at 1000 and 3330 µg/plate. Precipitation of Prisorine 3505 on the plated was observed at the start and at the end of the incubation period at the concentration of 3330 µg/plate in all tester strains.


RANGE-FINDING/SCREENING STUDIES:
Prisorine 3505 was tested in strain TA 100 with concentrations of 3, 10, 33, 100, 333, 1000, 3330 and 5000 µg/plate in the absence and presence of S9-mix.
Prisorine 3505 precipitated in the top agar at 1000 µg/plate and upwards. Precipitation of Prisorine 3505 was observed at the start and at the end of the incubation period at 3330 and 5000 µg/plate in tester strain TA 100.
No reduction of the bacterial lawn was observed.
In the absence of S9-mix a decrease in the number of revertants, less than 50% compared to the mean number of revertants of the solvent control, was observed at 33 µg/plate and upwards.
In the presence of S9-mix a decrease in the number of revertants was observed at 5000 µg/plate.
Based on these data, Prisorine 3505 was tested in the mutation assay up to and including a concentration of 3330 µg/plate in the absence and presence of S9-mix.


ADDITIONAL INFORMATION ON CYTOTOXICITY:
In the absence of S9-mix a decrease in the number of revertants, less than 50% compared to the mean number of revertants of the solvent control, was observed at 33 µg/plate and upwards in tester strain TA100, and at 1000 µg/plate and upwards in tester strain TA98.
In the presence of S9-mix a decrease in the number of revertants was observed at 333 µg/plate and upwards in tester strain TA100, and at 1000 µg/plate and upwards in tester strain TA 98.
All other concentraitons showed no decrease in the amount of revertants. The tester strains 1535 and TA 1537 showed no decrease in the amount of revertants.
The bacterial background lawn was not reduced at all concentrations tested.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Mutagenic response of Prisorine 3505 in the Salmonella thyphimurium reverse mutation assay

Experiment 1

Dose (µg/plate)	Mean number of revertants/plate ± SD (n=3)
	TA1535	TA 1537	TA 98	TA 100
	Without S9-mix
3				81 ± 3
10				87 ± 10
33	11 ± 4	8 ± 1	19 ± 2	65 ± 3
100	11 ± 3	8 ± 2	24 ± 2	64 ± 6
333	9 ± 3	7 ± 1	26 ± 24^2	60 ± 11
1000	8 ± 3	4 ± 2	11 ± 3	53 ± 11
3330 SP	8 ± 2	6 ± 2	14 ± 4	43 ± 5
5000 SP				49 ± 7
Solvent control^1	8 ± 1	4 ± 1	24 ± 3	93 ± 5
Positive control	149 ± 13	149 ± 25	301 ± 50	908 ± 24

 

Dose (µg/plate)	Mean number of revertants/plate ± SD (n=3)
	TA1535	TA 1537	TA 98	TA 100
	With S9-mix
3				86 ± 8
10				77 ± 4
33	10 ± 2	5 ± 1	27 ± 0	88 ± 6
100	7 ± 1	7 ± 1	29 ± 6	76 ± 6
333	9 ± 3	4 ± 2	26 ± 3	67 ± 2
1000	8 ± 3	5 ± 2	24 ± 5	70 ± 5
3330 SP	6 ± 2	5 ± 2	24 ± 3	70 ± 5
5000 SP				61 ± 15
Solvent control^1	11 ± 2	6 ± 1	27 ± 5	88 ± 5
Positive control	119 ± 21	236 ± 36	635 ± 21	997 ± 20

 

Experiment 2

Dose (µg/plate)	Mean number of revertants/plate ± SD (n=3)
	TA1535	TA 1537	TA 98	TA 100
	Without S9-mix
33	12 ± 3	8 ± 7	20 ± 3	57 ± 1
100	10 ± 6	7 ± 3	18 ± 4	51 ± 10
333	7 ± 3	8 ± 5	19 ± 3	47 ± 7
1000	8 ± 6	5 ± 2	16 ± 2	38 ± 12
3330 SP	11 ±3	5 ± 1	21 ± 9^2	33 ± 5
Solvent control^1	12 ± 5	6 ± 2	23 ± 2	70 ± 7
Positive control	192 ±29	217 ± 23	455 ± 84	1030 ± 58

 

Dose (µg/plate)	Mean number of revertants/plate ± SD (n=3)
	TA1535	TA 1537	TA 98	TA 100
	With S9-mix
33	8 ± 1	7 ± 2	23 ± 7	68 ± 4
100	11 ± 5	8 ± 4	22 ± 7	69 ± 6
333	12 ± 3	5 ± 1	22 ± 7	58 ± 11
1000	8 ± 5	6 ± 3	13 ± 1	49 ± 3
3330 SP	8 ± 5	4 ± 0	16 ± 3	41 ± 2
Solvent control^1	11 ± 4	7 ± 8^2	32 ± 17	77 ± 7
Positive control	354 ± 46	797 ± 24	711 ± 47	1151 ± 80

 

¹0.1 mL DMSO

²Plate infected

SP: Test substance precipitated slightly on the plates

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Based on the results of this study it is concluded that Prisorine 3505 is not mutagenic in the Salmonella typhimurium reverse mutation assay.