4-methylbenzyl alcohol

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:

May - September 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

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

21 July 1997

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Hess. Ministerium für Umwelt, Klimaschutz, Landwirtschaft und Verbraucherschutz, Wiesbaden, Germany

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4-methylbenzyl alcohol

EC Number:

209-639-1

EC Name:

4-methylbenzyl alcohol

Cas Number:

589-18-4

Molecular formula:

C8H10O

IUPAC Name:

(4-methylphenyl)methanol

Method

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Phenobarbital/β-naphthoflavone induced rat liver S9

Test concentrations with justification for top dose:

33, 100, 333, 1000, 2500, and 5000 μg/plate
No toxic effects were observed at 5000 μg/plate in the pre-experiment.

Vehicle / solvent:

DSMO

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

TA 1535, TA 100 (Without metabolic activation)

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

TA 1537, TA98 (Without metabolic activation)

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylene-diamine

Remarks:

WP2 uvrA (Without metabolic activation)

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

TA 1535, TA 1537, TA 98, TA 100, WP2 uvrA (With metabolic activation)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: 60 min at 37 °C
- Exposure duration: 48 h at 37 °C

SELECTION AGENT: L-Histidin for S. typhimurium, Tryptophan for E. coli

NUMBER OF REPLICATIONS: 3

Titer of the incubated culture: 10^8 - 10^9 cells/mL.

DETERMINATION OF CYTOTOXICITY
- Method: Background lawn

Evaluation criteria:

Since a reduced background lawn is regarded to be a cytotoxic effect, plates with reduced background lawn (only at 5000 μg/plate) were not included into evaluation procedures.
The test item is to be interpreted mutagenic if there is a concentration effect relationship and the induction rate is >=2.

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:

valid

Positive controls validity:

valid

Test results 2

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:

valid

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:

valid

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:

cytotoxicity

Remarks:

at 5000 μg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 5000 μg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

PRE-EXPERIMENT:
3; 10; 33; 100; 333; 1000; 2500; and 5000 μg/plate
No toxic effects occurred in the Pre-experiment

HISTORICAL CONTROL DATA
see table at "Any other information"

ADDITIONAL INFORMATION ON CYTOTOXICITY:
- Measurement of cytotoxicity used: reduced background lawn
- TA 100: with and without metabolic activation at 5000 μg/plate cytotoxic effects
- WP2 uvrA:with metabolic activation at 5000 μg/plate cytotoxic effects

Any other information on results incl. tables

Substance	Concentration (µg/plate)	S9	Mean revertants per plate
			TA1535	TA1537	TA98	TA100	WP2 uvrA
Control	0	-	7.0	10.3	29.7	200.7	48.3
Solvent control	0	-	8.7	10.7	26.7	145.3	50.0
Test item	33	-	9.7	9.0	26.3	148.0	46.0
Test item	100	-	7.3	11.0	25.0	155.0	34.7
Test item	333	-	7.0	8.3	25.3	154.3	34.7
Test item	1000	-	11.0	8.0	25.0	100.7	36.0
Test item	2500	-	9.0	8.0	25.0	105.0	34.0
Test item	5000	-	8.3	10.3	17.7	55.3	17.7
NaN3	10	-	111.3			1805.3
4-NOPD	50	-		103.3
4-NOPD	10	-			301.0
MMS	2	-					637.3
Control	0	+	10.3	12.0	45.7	203.7	58.7
Solvent control	0	+	12.3	15.7	41.3	138.0	52.3
Test item	33	+	9.7	14.7	38.3	153.0	54.7
Test item	100	+	12.3	11.7	38.3	134.0	53.7
Test item	333	+	10.7	12.0	40.0	148.3	51.0
Test item	1000	+	10.0	13.3	50.7	109.0	50.3
Test item	2500	+	8.0	14.3	37.3	89.0	49.3
Test item	5000	+	9.3	11.0	24.3	27.3	26.0
2-AA	2.5	+	316.7	121.0	4196.7	2183.7
2-AA	10	+					544.7

NaN3: sodium azide

4-NOPD: 4-nitro-o-phenylene-diamine

MMS: methyl methane sulfonate

2-AA: 2-aminoanthracene

Historical control data

Strain		Without S9 mix				With S9 mix
		Mean	SD	Min	Max	Mean	SD	Min	Max
TA 1535	Solvent control	12	2.5	6	25	12	2.5	7	26
	Untreated control	12	3.1	6	28	12	2.9	7	26
	Positive control	1130	143.1	334	1816	388	58.2	176	668
TA1537	Solvent control	10	2.2	6	19	13	3.5	7	30
	Untreated control	11	2.7	5	21	14	4.0	7	31
	Positive control	82	12.7	43	157	191	60.8	83	434
TA 98	Solvent control	25	4.4	13	43	34	6.2	15	58
	Untreated control	27	4.9	12	43	37	6.5	11	57
	Positive control	378	73.7	211	627	3949	771.8	360	6586
TA 100	Solvent control	156	26.0	78	209	148	32.3	73	208
	Untreated control	176	23.6	79	217	172	25.4	85	218
	Positive control	1966	293.2	498	2767	3798	830.4	536	6076
WP2 uvr A	Solvent control	41	5.6	27	63	50	6.8	28	72
	Untreated control	42	5.8	30	63	52	6.8	36	88
	Positive control	798	362.7	319	4732	378	112.6	167	1265

Applicant's summary and conclusion

Conclusions:

The mutagenicity of the test item was determined in a study according to OECD guideline 471. The results indicate that the test item under the experimental conditions described, was not mutagenic to Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100, and to the Escherichia coli strain WP2 uvrA in the presence and absence of a metabolizing system.

Executive summary:

The mutagenicity of the test substance was studied with four mutant strains of Salmonella typhimurium (TA1535, TA1537, TA98 and TA100) and one strain of Escherichia coli (WP2 uvrA) according to OECD guideline 471 and EU method B13/14. The investigations were carried using the standard plate incorporation assay with and without liver homogenate (S9) from Phenobarbital/β-naphthoflavone induced rat liver. The test substance was dissolved in DMSO and tested in concentrations of 33 to 5000 µg per plate. Cytotoxicity was recorded as reduced background lawn with the strain TA 100 at 5000 μg/plate with and without metabolic activation and with the strain WP2 uvrA at 5000 μg/plate with metabolic activation. Sodium azide, 4-nitro-o-phenylene-diamine, methyl methane sulfonate and 2-aminoanthracene served as positive controls to confirm the reversion properties and the specificity of the bacterial strains as well as the efficacy of the metabolizing system. In the concentration range investigated, the test substance did not induce a significant increase in the mutation frequency of the tester strains in the presence and absence of a metabolic activation system. In conclusion, these results indicate that under the experimental conditions described, the test item was not mutagenic to Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100 or to Escherichia coli strain WP2 uvrA in the presence and absence of a metabolizing system.