2-phenylethanol

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant, guideline study, reliable without restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5375 - In vitro Mammalian Chromosome Aberration Test

Principles of method if other than guideline:

The study design also meets the requirements of UK Department of Health Guidelines for Testing of Chemicals for Mutagenecy

GLP compliance:

yes (incl. QA statement)

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

Phenylethyl alcohol

IUPAC Name:

Phenylethyl alcohol

Method

Test concentrations with justification for top dose:

Final concentration of Phenylethyl alcohol CAS No 60-12-8: (µg/ml)
Experiment 1
4(20)-hour without S9: 0*, 38.13, 76.25, 152.5, 305*, 610*, 1220*, MMC 0.4*
4(20)-hour with S9 0*: 38.13, 76.25, 152.5, 305*, 610*, 1220*, CP 5*

Experiment 2
24-hour without S9: 0*, 38.13, 76.25, 152.5, 305*, 610*, 1220*, MMC 0.2*

*Dose levels selected for metaphase analysis
4(20)-hour with S9 (2%): 0*, 38.13, 76.25, 152.5, 305*, 610*, 1220*, CP 5*

Vehicle / solvent:

Vehicle and positive controls were used in parallel with the test item.
Positive control items:
-In the absence of S9, mitomycin C (MMC) (Sigma, Batch No. 089K0731) was used at 0.4 and 0.2 µg/ml for cultures in Experiment 1 and 2 respectively. It was dissolved in Minimal Essential Medium.
-In the presence of S9, cyclophosphamide (CP) (Acros, Batch No. A0302605) was used at 5 µg/ml in both experiments. It was dissolved in dimethyl sulphoxide.

Details on test system and experimental conditions:

Duplicate lymphocyte cultures (A and B) were established for each dose level by mixing the following components, giving, when dispensed into sterile plastic flasks for each culture:
-8.05-9.05 ml MEM, 10% (FBS)
-0.1 ml Li-heparin
-0.1 ml phytohaemagglutinin
-0.75 ml heparinised whole blood

Evaluation criteria:

The dose range for the Preliminary Toxicity Test was 4.77, 9.53, 19.06, 38.13, 76.25, 152.5, 305, 610, 1220 µg/ml. The maximum dose was the maximum recommended dose level, the 10 mM concentration. No precipitate of the test item was observed in the parallel blood-free cultures at the end of the exposure in any exposure group.
Microscopic assessment of the slides prepared from the exposed cultures showed that metaphase cells were present up to 1220 µg/ml in all three exposure groups. In the 24-hour exposure group the test item induced a dose related increase in toxicity and achieved 81% mitotic inhibition at 1220 µg/ml and 57% mitotic inhibition at 610 µg/ml. The 4(20)-hour exposure group in the presence of S9 demonstrated a more modest increase in toxicity with 25% mitotic
inhibition at 1220 µg/ml.
The selection of the maximum dose level was based on the maximum recommended dose level, the 10 mM concentration and was 1220 µg/ml for the 4(20)-hour exposure groups and for the continuous exposure group used in Experiment 2.

Statistics:

The frequency of cells with aberrations excluding gaps and the frequency of polyploid cells was compared, where necessary, with the concurrent vehicle control value using Fisher's Exact test.

Results and discussion

Test results

Species / strain:

lymphocytes: Not specified

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:

Preliminary Test
The dose range for the Preliminary Toxicity Test was 4.77, 9.53, 19.06, 38.13, 76.25, 152.5, 305, 610, 1220 µg/ml. The maximum dose was the maximum recommended dose level, the 10 mM concentration. No precipitate of the test item was observed in the parallel blood-free cultures at the end of the exposure in any exposure group.
Experiment 1 and 2
The maximum dose level selected for metaphase analysis was the maximum recommended dose level, the 10 mM concentration dose level (1220 µg/ml). No precipitate of the test item was observed at the end of exposure in either exposure group. No marked dose-related inhibition of mitotic index was observed. All of the vehicle control cultures had frequencies of cells with chromosome aberrations within the expected range.
(See attached document for results)

Remarks on result:

other: strain/cell type: mammalian cells

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

The test item did not induce any statistically significant increases in the frequency of cells
with aberrations either in the absence or presence of metabolic activation.

Executive summary:

An in vitro study for the detection of structural chromosomal aberrations in cultured mammalian cells was conducted on the test item Phenyl ethyl alcohol. Cultures of human lymphocytes were treated with the test item in duplicate and were evaluated for chromosome aberrations at three dose levels, together with vehicle and positive controls. Four treatment conditions were used for the study; i.e. In Experiment 1, 4 hours in the presence of an induced rat liver homogenate metabolising system (S9), at a 2% final concentration with cell harvest after a 20-hour expression period and a 4 hours exposure in the absence of metabolic activation (S9) with a 20-hour expression period. In Experiment 2, the 4 hours exposure with addition of S9 was repeated (using a 1% final S9 concentration), whilst in the absence of metabolic activation the exposure time was increased to 24 hours. The result of the test showed that the test item did not induce any statistically significant increases in the frequency of cells with chromosome aberrations in either the absence or presence of a liver enzyme metabolising system in either of two separate experiments. The test item Phenyl ethyl alcohol is not therefore considered to be clastogenic to human lymphocytes in vitro.