Thuya plicata, ext.

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 dec 2016 to 13 april 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Remarks:

see study director statement and GLP page 4 of the final report

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Thuya plicata, ext.

EC Number:

305-105-8

EC Name:

Thuya plicata, ext.

Cas Number:

94334-32-4

Molecular formula:

not relevant as a UVCB substance

IUPAC Name:

Water steam distillation of needles and twigs of Thuya plicata

Test material form:

liquid

Specific details on test material used for the study:

batch number 4425
production date : 10 oct 2016
expiry date : 10 oct 2019

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Test concentrations with justification for top dose:

5000, 1500, 500, 150 and 50 µg/plate

Vehicle / solvent:

Vehicle used to solubilize test item ; Ethanol

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

7,12-dimethylbenzanthracene

9-aminoacridine

2-nitrofluorene

sodium azide

other: cis-platinum (II) diamine dichloride

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Doses (5000, 1500, 500, 150 and 50 µg/plate) prepared from solutions of the test item Thuya plicata essential oil (BATCH 4425 - LEMI code: GGH-211116-2) provided by SNPM, do not induce any mutagenic change in Salmonella typhimurium TA 1535, TA 1537, TA 98, TA 100 and in Escherichia coli WP2(uvrA¯) (pKM 101) without, or with metabolic activation, according to the OECD Guidelines n° 471.