7-methyl-3-methyleneocta-1,6-diene

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

GLP study conducted equivalent or similar to OECD Guideline 471 with deviations: one stain missing and no individual plate counts available.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

one stain missing and no individual plate counts

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

7-methyl-3-methyleneocta-1,6-diene

EC Number:

204-622-5

EC Name:

7-methyl-3-methyleneocta-1,6-diene

Cas Number:

123-35-3

Molecular formula:

C10H16

IUPAC Name:

7-methyl-3-methylideneocta-1,6-diene

Test material form:

liquid

Method

Target gene:

Not applicable

Species / strain

Species / strain / cell type:

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

Details on mammalian cell type (if applicable):

not applicable

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

10 or 30% S9 fraction of Aroclor 1254-induced male Sprague-Dawley rat or Syrian hamster liver

Test concentrations with justification for top dose:

0, 33, 100, 333, 1000, 3333 or 10000 µg/plate

Vehicle / solvent:

No data

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (with all strains)

Remarks:

with metabolic activation

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: sodium azide (TA100 and TA1535), 9-aminoacridine (TA97), 4-nitro-o-phenylenediamine (TA98)

Remarks:

without metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: In agar (plate incorporation)

DURATION
- Exposure duration: 20 minutes at 37 °C and 2 days at 37 °C

NUMBER OF REPLICATIONS: Triplicate

Evaluation criteria:

- A positive response is defined as a reproducible, dose-related increase in histidine-independent (revertant) colonies in any one strain/activation combination.
- An equivocal response is defined as an increase in revertants that is not dose related, is not reproducible, or is not of sufficient magnitude to support a determination of mutagenicity.
- A negative response is obtained when no increase in revertant colonies is observed following chemical treatment.
- There is no minimum percentage or fold increase required for a chemical to be judged positive or weakly positive.

Statistics:

No data

Results and discussion

Test results

Key result

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:

cytotoxicity

Remarks:

at or above 3333 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

None

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1: Mutagenicity of β-Myrcene in Salmonella typhimurium^a

Strain	Dose (µg/plate)	Revertants/Plate^b
		–S9		+hamster S9		+rat S9
		Trial 1	Trial 2	10%	30%	10%	30%
Study performed at SRI International
TA100	0	103 ± 2.0	114 ± 6.0	104 ± 8.0	108 ± 6.0	107 ± 8.0	110 ± 5.0
	33	113 ± 6.0	96 ± 11.0	98 ± 6.0		126 ± 22.0
	100	100 ± 6.0	116 ± 0.0	103 ± 7.0	94 ±6.0	116 ± 10.0	119 ± 4.0
	333	96 ± 8.0	107 ± 10.0	101 ± 10.0	101 ± 4.0	115 ± 21.0	113 ± 4.0
	1000	100 ± 6.0	117 ± 3.0	81 ± 4.0	111 ± 4.0	90 ± 14.0	111 ± 10.0
	3333	66 ± 6.0^c	70 ± 9.0^c	59 ± 4.0^c	107 ± 10.0	55 ± 8.0^c	103 ± 4.0
	10000				75 ± 6.0^c		77 ± 2.0^c
Trial summary		Negative	Negative	Negative	Negative	Negative	Negative
Positive control^d		781 ± 17.0	765 ± 39.0	597 ± 8.0	663 ± 31.0	488 ± 23.0	553 ± 52.0
TA1535	0	9 ± 2.0	13 ± 2.0	10 ± 2.0	9 ± 0.0	9 ± 1.0	12 ± 1.0
	33	9 ± 2.0	8 ± 2.0	12 ± 3.0		10 ± 1.0
	100	6 ± 1.0	10 ± 2.0	9 ± 1.0	11 ± 1.0	12 ± 1.0	11 ± 1.0
	333	10 ± 1.0	9 ± 1.0	8 ± 3.0	9 ± 1.0	11 ± 1.0	10 ± 1.0
	1000	9 ± 1.0	9 ± 1.0	9 ± 2.0	10 ± 2.0	10 ± 1.0	9 ± 0.0
	3333	6 ± 0.0^c	7 ± 1.0^c	4 ± 1.0^c	5 ± 1.0	5 ± 0.0^c	10 ± 1.0
	10000				5 ± 2.0^c		8 ± 0.0^c
Trial summary		Negative	Negative	Negative	Negative	Negative	Negative
Positive control^d		700 ± 13.0	819 ± 48.0	92 ± 11.0	363 ± 5.0	89 ± 12.0	196 ± 8.0
TA97	0	106 ± 0.0	126 ± 16.0	162 ± 9.0	144 ± 4.0	172 ± 7.0	145 ± 7.0
	33	104 ± 7.0	111 ± 9.0	167 ± 5.0		157 ± 6.0
	100	100 ± 8.0	127 ± 10.0	159 ± 3.0	149 ± 4.0	154 ± 10.0	128 ± 11.0
	333	96 ± 4.0	142 ± 13.0	151 ± 16.0	112 ± 2.0	161 ± 7.0	106 ± 5.0
	1000	106 ± 6.0	144 ± 14.0	142 ± 18.0	117 ± 11.0	153 ± 8.0	121 ± 10.0
	3333	63 ± 29.0^c	77 ± 6.0c	106 ± 3.0^c	125 ± 7.0	89 ± 21.0^c	132 ± 2.0
	10000				117 ± 9.0c		124 ± 2.0c
Trial summary		Negative	Negative	Negative	Negative	Negative	Negative
Positive control^d		293 ± 22.0	575 ± 53.0	689 ± 1.0	609 ± 28.0	648 ± 15.0	431 ± 35.0
TA98	0	22 ± 4.0	16 ± 2.0	19 ± 4.0	16 ± 1.0	19 ± 3.0	17 ± 2.0
	33	12 ± 2.0	9 ± 1.0	23 ± 2.0		26 ± 1.0
	100	16 ± 2.0	11 ± 1.0	19 ± 1.0	18 ± 2.0	20 ± 3.0	13 ± 2.0
	333	19 ± 5.0	11 ± 2.0	22 ± 4.0	18 ± 4.0	19 ± 1.0	16 ± 1.0
	1000	24 ± 5.0	11 ± 1.0	20 ± 1.0	23 ± 4.0	18 ± 0.0	13 ± 2.0
	3333	8 ± 2.0^c	7 ± 1.0^c	8 ± 1.0^c	22 ± 2.0	12 ± 3.0^c	18 ± 3.0
	10000				9 ± 1.0^c		11 ± 3.0^c
Trial summary		Negative	Negative	Negative	Negative	Negative	Negative
Positive control^d		294 ± 8.0	269 ± 5.0	278 ± 21.0	237 ± 16.0	206 ± 26.0	251 ± 21.0

^a The detailed protocol for the SRI International study is presented by Zeiger et al. (1992); the study performed at SITEK Research

Laboratories used a modification of that protocol, 0 µg/plate was the solvent control

^b Revertants are presented as mean ± standard error from three plates.

^c Slight toxicity

^d The positive controls in the absence of metabolic activation were sodium azide (TA100 and TA1535), 9-aminoacridine (TA97) and 4-nitro-o-phenylenediamine (TA98. The positive control for metabolic activation with all strains was 2-aminoanthracene.

Applicant's summary and conclusion

Conclusions:

β-Myrcene was not mutagenic in S. typhimurium TA1535, TA 1537, TA 98 and TA 100 with and without metabolic activation.

Executive summary:

An Ames test was performed to determine the mutagenicity potential of β‑myrcene according to a method equivalent or similar to Guideline OECD 471 in compliance with Good Laboratory Practice Regulations.

Salmonella typhimurium strains TA1535, 1537, 98 and 100 were treated with β‑myrcene using the plate incorporation method at concentration range of 33 - 10000 µg/plate both with and without metabolic activation (10 or 30% S9 fraction of Aroclor 1254-induced male Sprague-Dawley rat or Syrian hamster liver). Concurrent strain-specific positive and solvent controls, both with and without metabolic activation, were included in each assay. 

 

Positive controls induced appropriate responses in the corresponding strains. β-Myrcene showed no substantial increase in revertant colony members over control at any concentrations in presence and absence of metabolic activation.

 

Therefore, β-myrcene is not considered as mutagenic according to Directive 67/548/EEC and CLP regulation (EC) N° 1272/2008.