Methyl phenylacetate

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:

2000-11-10 to 2001-02-08

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

1997

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Methyl phenylacetate

EC Number:

202-940-9

EC Name:

Methyl phenylacetate

Cas Number:

101-41-7

Molecular formula:

C9H10O2

IUPAC Name:

methyl phenylacetate

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 98

Species / strain 3

Species / strain / cell type:

S. typhimurium, other: TA97a

Species / strain 4

Species / strain / cell type:

S. typhimurium TA 100

Species / strain 5

Species / strain / cell type:

S. typhimurium TA 102

Metabolic activation:

with and without

Metabolic activation system:

Induced with Phenobarbital intraperitoneally and 13-Naphtoflavone orally

Test concentrations with justification for top dose:

0.05 - 0.16 - 0.5 - 1.6 - 5 mg/plate

Vehicle / solvent:

DMSO

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: ICR 191 acridine mutagen dihydrochloride

Remarks:

TA97a (without metabolic activation)

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-Nitro-1,2-phenylenediamine

Remarks:

TA98 (without metabolic activation)

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: Nitrofurantoine

Remarks:

TA100 (without metabolic activation)

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

TA1535 (wihtout metabolic activation)

Controls 5

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-Aminoanthraceen

Remarks:

TA 97a, TA 98, TA 100, TA 1535 (with metabolic activation)

Controls 6

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: Cumene Hydroperoxide

Remarks:

TA102 (without metabolic activation)

Controls 7

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: Danthron

Remarks:

TA102 (with metabolic activation)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h at 37 °C (Plates of the mutagenicity test)
24 h (Plates for confirmation of the genotypes)

SELECTION AGENT: L-Histidin

NUMBER OF REPLICATIONS: 3

Titer of the overnight culture: > 1*10^8 cells/mL.

DETERMINATION OF CYTOTOXICITY
- Method: Background lawn

OTHER EXAMINATIONS:
- Other: Genotypes were evaluated for each study.

Evaluation criteria:

Since a reduced background lawn is regarded to be a cytotoxic effect, plates with reduced background lawn were not included into evaluation procedures.
Arithmetic mean values and standard deviations were calculated from colonies per plate of three replicates. For evaluation of the results the induction rate of the mean values was calculated :
Induction rate: revertant colonies of test item/revertant colonies of the corresponding control
The test item is to be interpretated mutagenic if there is a concentration effect relationship and the induction rate is >=2. The data presented in the tables are computer generated and rounded for presentation. Thus manual calculation of results based an the data in this report may yield minor deviations from these figures.

Results and discussion

Test results

Test results 1

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:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium, other: TA97a

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

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:

valid

Untreated negative controls validity:

not examined

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:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

S. typhimurium TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

ADDITIONAL INFORMATION ON CYTOTOXICITY: TA97a showed at a concentration of 5 mg/plate with and without metabolic activation cytotoxic effects. The other strains showed no cytotoxic effects.

Any other information on results incl. tables

	Concentration (mg/plate)	S9	TA97a	TA98	TA100	TA102	TA 1535
	5	-	n.a.	22	109	93	37
	1.6	-	334	24	157	307	39
	0.5	-	311	33	162	294	32
	0.16	-	355	21	155	357	29
	0.05	-	407	31	131	307	27
2nd test	5	-	173	31	77	258	20
	1.6	-	325	29	152	463	26
	0.5	-	422	32	125	486	19
	0.16	-	388	32	142	484	19
	0.05	-	415	34	158	554	19
	5	+	n.a.	13	94	298	21
	1.6	+	292	22	100	300	13
	0.5	+	341	21	98	287	14
	0.16	+	329	32	80	251	14
	0.05	+	349	23	79	241	12
2nd test	5	+	n.a.	34	102	439	11
	1.6	+	306	45	131	539	11
	0.5	+	326	36	118	647	10
	0.16	+	340	45	129	639	16
	0.05	+	434	38	107	708	14
ICR		-	>3.1 (1st test), >3.3 (2nd test)
2-AA		+	>3.8 (1st test), >3.6 (2nd test)	>45.3 (1st test), >32.1 (2nd test)	>11.8 (1st test), >9.3 (2nd test)		9.8 (1st test), 6.3 (2nd test)
	4-nitro-1,2-phenylenediamine	-		6.0 (1st test), 3.6 (2nd test)
	Nitrofurantoine	-			3.5 (1st test), 2.4 (2nd test)
	Cumene hydroperoxide	-				>3.7 (1st test), >2.8 (2nd test)
Danthron		+				>2.7 (1st test), >2.2 (2nd test)
Sodium azide		-					9.0 (1st test), 9.9 (2nd test)

Applicant's summary and conclusion

Conclusions:

In this study the test item was found to have no mutagenic effects an Salmonella typhimurium strains TA 97 a, TA 98, TA 100, TA 102 and TA 1535 with (+) and without (-) the metabolic activation system S9 from male Wistar rats at concentrations up to 5 mg/plate.

Executive summary:

The mutagenic effects of the test item were determined in a reverse mutation assay according to the principles of OECD Guideline No. 471 and EEC Directive 2000/32/EEC Method B. 13/14. Test systems were the Salmonelle typhimurium strains TA 97a, TA 98, TA 100, TA 102 and TA 1535 with (+) and without (-) the metabolic activation system S9 (from male Wistar rats) each. Positive and negative controls were included in each study. Duration of each study was 48 h. The test item was dissolved in DMSO and applied once at test initiation with the concentrations 0.05 - 0.16 - 0.5 - 1.6 - 5 mg/plate. The test substance showed no mutagenic effects with and without metabolic activation. Cytotoxic effects were observed only for TA97a in the highest concentration of 5 mg/plate.