Peppermint, ext.

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro DNA damage and/or repair study

Remarks:

Type of genotoxicity: DNA damage and/or repair

Type of information:

experimental study

Adequacy of study:

key study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test is performed similar to OECD Guideline 479; non GLP; Acceptable basic data.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2001

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 479 (Genetic Toxicology: In Vitro Sister Chromatid Exchange Assay in Mammalian Cells)

Deviations:

no

GLP compliance:

no

Type of assay:

sister chromatid exchange assay in mammalian cells

Test material

Test material information

Constituent 1

Reference substance name:

peppermint oil

IUPAC Name:

peppermint oil

Details on test material:

- Name of test material (as cited in study report): essential oil extracted from peppermint (Menthaxpiperita L.)
- Composition of test material, percentage of components: menthol (59.17%), menthone (18.78%), L-limonene (5.16%), isomenthone (3.55%), ß-caryophyllene (2.93%), germacrene (1.73%), caryophyllene oxide (1.67%), bornyl acetate (1.08%), caraway aldehyde (0.61%), ß-pinene (0.61%), α-pinene (0.56%), myrcene (0.34%), eucalyptol (0.32%), isoeugenol (0.32%), methylcinemate (0.27%), sabinene (0.26%), ß-ocymene (0.25%).

Method

Target gene:

Not relevant

Species / strain

Species / strain / cell type:

lymphocytes: human whole peripheral blood culture

Details on mammalian cell type (if applicable):

- Type and identity of media: HEPES-buffered RPMI 1640 medium

Metabolic activation:

without

Metabolic activation system:

As whole blood cultures display many properties common with the liver microsomal cytochrome P450 system, no external metabolising enzymes were added.

Test concentrations with justification for top dose:

0.10, 0.15, 0.20, 0.25, and 0.30 µl/ml

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: acetone 2.3 µl/ml

Controls

Untreated negative controls:

yes

Remarks:

untreated cells

Negative solvent / vehicle controls:

yes

Remarks:

acetone

True negative controls:

no

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

Migrated to IUCLID6: 0.015 µl/ml

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 24 hours
- Fixation time (start of exposure up to fixation or harvest of cells): 24 hours

SPINDLE INHIBITOR (cytogenetic assays): Colchicine (0.5 ug/ml) for the last 3 hours of incubation
STAIN (for cytogenetic assays): Giemsa

NUMBER OF REPLICATIONS: Duplicate cultures for each treatment

NUMBER OF CELLS EVALUATED: No less than 25 second-mitotic division cells per culture were analysed

DETERMINATION OF CYTOTOXICITY
- Method: other: Cell replicative kinetics ((RI) Replicative Index). RI shows the average number of times cells have divided in culture.

OTHER: No less than 2 pilot experiments (using 2 to 3 concentrations) preceded 3 representative experiments.

Evaluation criteria:

No data

Statistics:

Statistical significance was confirmed by means of the Mann-Whitney U-test and the z-test (p < 0.05).

Results and discussion

Test results

Species / strain:

lymphocytes: human whole peripheral blood culture

Metabolic activation:

without

Genotoxicity:

negative

Remarks:

Relative weak SCE induction in a dose-independent manner

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING/SCREENING STUDIES: 2 pilot experiments (using 2 to 3 concentrations) preceded 3 representative experiments. As in all cases good quantitative correspondence between pilot and main experiments was found, only pooled results of representative experiments were reported in this paper.

COMPARISON WITH HISTORICAL CONTROL DATA: No data

ADDITIONAL INFORMATION ON CYTOTOXICITY: Peppermint oil (Menthaxpiperita L.) clearly inhibited cell replicative kinetics. At concentrations of 0.20 ul/ml and above statistically significant inhibition of cell replicative kinetics was evident ((RI) Replicative Index).

Any other information on results incl. tables

Peppermint essential oil was a relative weak SCE inducer, it induced SCE in a dose-independent manner at cytotoxic concentrations. It seems that at high doses of Peppermint essential oil "saturation" of SCE-inducing capacity occurs.

 

Dose               SCE/cell ± S.E.M.

0.10 ul/ml       8.4 ± 0.4

0.15 ul/ml       10.2 ± 0.6

0.20 ul/ml       8.5 ± 0.3

0.25 ul/ml       10.1 ± 0.5

0.30 ul/ml       9.1 ± 0.4

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative without metabolic activation

Peppermint essential oil (Menthaxpiperita L.). was a relative weak SCE inducer, it induced SCE in a dose-independent manner at cytotoxic concentrations.

Executive summary:

A Sister Chromatid Exchange (SCE) test in vitro using human lymphocytes (whole peripheral blood cultures) was carried out on the essential oils extracted from peppermint (Menthaxpiperita L.). The test was performed similar to OECD Guideline 479. As whole peripheral blood cultures display many properties common with the liver microsomal cytochrome P450 system, no external metabolising enzymes were added. The cells were continuously exposed to peppermint oil at 0.10, 0.15, 0.20, 0.25, and 0.30 ul/ml for 24 hours. Cell replicative kinetics was determined by means of Replicative Index (RI).

Peppermint oil (Menthaxpiperita L.) clearly inhibited cell replicative kinetics. At concentrations of 0.20 ul/ml and above statistically significant inhibition of cell replicative kinetics was evident. Peppermint essential oil was a relative weak SCE inducer, it induced SCE in a dose-independent manner at cytotoxic concentrations. It seems that at high doses of Peppermint essential oil "saturation" of SCE-inducing capacity occurs.