Reaction mass of tridecanal and 2-methyldodecanal and pentadecanal and 2-methyltetradecanal

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

06 July - 10 September, 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study and GLP conform. Reliability has been set to 2 as study is used within a ReadAcross Approach. Read-across hypothesis: for details please see read-across report in IUCLID section 13

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Undecanal

EC Number:

203-972-6

EC Name:

Undecanal

Cas Number:

112-44-7

Molecular formula:

C11H22O

IUPAC Name:

undecanal

Method

Target gene:

HPRT (hypoxanthine-guanine phosphoribosyl transferase)

Species / strain

Species / strain / cell type:

Chinese hamster lung fibroblasts (V79)

Details on mammalian cell type (if applicable):

- Type and identity of media: MEM (minimal essential medium) containing Hank’s salts, neomycin (5 µg/mL) and amphotericin B (1 %).
- Properly maintained: yes
- Periodically checked for Mycoplasma contamination: yes
- Periodically checked for karyotype stability: yes
- Periodically "cleansed" against high spontaneous background: yes

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

Phenobarbital/ß-naphthoflavone induced rat liver S9 from male Wistar rats

Test concentrations with justification for top dose:

1st experiment: exposure 4 hours; 0.6-20 µg/mL without //7.2-230 µg/mL with S-9 mix
2nd experiment:
exposure 24 hours; 0.6-25 µg/mL without S-9 mix;
exposure 4 hours; 7.l8-500 µg/mL with S-9 mix

Vehicle / solvent:

- Vehicle used: DMSO
- Justification for choice of solvent/vehicle: low solubility of test article

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: EMS (ethylmethane sulfonate; CAS no. 62-50-0), DMBA (7,12-dimethylbenz(a)anthracene; CAS no. 57-97-6)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation; in suspension; as impregnation on paper disk

DURATION
- Preincubation period: 24 hours
- Exposure duration: 4 hrs in the 1st experiment; 24 hrs without S-9 mix, 4 hrs with S-9 mix, in the 2nd experiment
- Expression time (cells in growth medium): 7 days
- Selection time (if incubation with a selection agent): 7 or 8 days
- Fixation time (start of exposure up to fixation or harvest of cells): 7 or 8 days

SELECTION AGENT (mutation assays): 6-thioguanine
SPINDLE INHIBITOR (cytogenetic assays): not required
STAIN (for cytogenetic assays): not required

NUMBER OF REPLICATIONS: 2

NUMBER OF EXPERIMENTS: 2

NUMBER OF CELLS EVALUATED: all surviving colonies counted

DETERMINATION OF CYTOTOXICITY
- Method: cloning efficiency

Evaluation criteria:

A test item is classified as positive if it induces either a concentration-related increase of the mutant frequency or a reproducible and positive response (i.e. at least 3 times the spontaneous mutation frequency) at one of the test points.

Statistics:

A linear regression (least squares) was performed to assess a possible dose dependent increase of mutant frequencies. The number of mutant colonies obtained for the groups treated with the test item were compared to the solvent control groups. A trend is judged as significant whenever the p-value (probability value) is below 0.05.

Results and discussion

Test results

Species / strain:

Chinese hamster lung fibroblasts (V79)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

7.5-20 µg/mL/without S-9 mix); 250 mµ/mL with S-9 mix

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: precipitation was seen at 115 µg/mL and above

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Read-across justification: for details please see read-across report in IUCLID section 13

Tab 1: The cell cultures were evaluated at the following concentrations:

exposure period	S9 mix	concentrations in µg/mL
		Experiment I
4 hours	-	0.6	1.3	2.5	5.0	7.5	10.0*	15.0*
4 hours	+			28.8	57.5	115.0^P	172.5^P	230.0^P
		Experiment II
24 hours	-			2.5	5.0	10.0	15.0	20.0
24 hours	+			31.3	62.5	125.0^P	187.5^P	500.0^P

P = precipitation

*     mutagenicity evaluation was performed only in culture II

For further details see the Summary of results (attached document)

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Undecanal was not mutagenic in a mammalian cell HPRT assay.

Executive summary:

Undecanal was tested for its genotoxic potential in mammalian cells in-vitro (Chinese hamster, V79 cells) at concentrations from 0.6 to 500 µg/mL in the presence and absence of metabolic activation. The assay was conducted according to the OECD TG 476 and under GLP conditions. Precipitation of undecanal was seen at 115 µg/mL and above. In the first experiment, cytotoxicity was seen at 7.5 and 20 µg/mL and higher in the absence of metabolic activation after a 4-hour exposure period. In the second experiment, cytotoxicity was seen at 25 µg/ml without S-9 mix (exposure period 24 hours), and at 500 µg/mL (with S-9 mix, exposure period 4 hours).

Undecanal did not increase the mutation frequency such that the evaluation criteria for rating the test substance as positive were met. Vehicle and positive controls performed as expected and were comparable with historical control data of this laboratory. Therefore, undecanal was considered to be non-mutagenic in this HPRT assay (Harlan, 2010).

This study is considered to be valid and suitable for assesement.