Heptane

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:

1982-1983

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1983

Report date:

1982

Reference 2

Reference Type:

publication

Title:

Unnamed

Year:

1988

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Principles of method if other than guideline:

No specific method or guideline was noted; similar to OECD guideline 471; limited documentation

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Heptane

EC Number:

205-563-8

EC Name:

Heptane

Cas Number:

142-82-5

Molecular formula:

C7H16

IUPAC Name:

heptane

Details on test material:

- Name of test material (as cited in study report): Heptane
- Analytical purity: 100% pure commercial product

Method

Target gene:

His-operon (Salmonellla), Trp-operon (E. coli)

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:

S. typhimurium TA 1538

Species / strain 3

Species / strain / cell type:

E. coli WP2

Species / strain 4

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

S9 mix of livers from Aroclor1254-pretreated rats

Test concentrations with justification for top dose:

max. conc. tested: 250 µg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: Tween80/ethanol

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

not specified

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: benzo[a]pyrene in DMSO, 4-nitroquinoline-N-oxide in DMSO, sodium azide, neutral red, potassium dichromate

Details on test system and experimental conditions:

METHOD OF APPLICATION: preincubation


DURATION
- Preincubation period: no data
- Exposure duration: not applicable, preincubation method
- Expression time (cells in growth medium): 48-72 hours


DETERMINATION OF CYTOTOXICITY
- Method: other: toxicity screening test

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:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

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:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

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:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

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:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Test results 6

Key result

Species / strain:

E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Test results 7

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

'Test system'.

Any other information on results incl. tables

The addition of heptane at amounts up to 250 µg per mL to cultures of Escherichia coli WP2 and WP2 uvr A, Salmonella typhimurium TA 1535, TA 1537, TA 1538, TA 98, and TA 100 did not lead to an increase in the reverse gene mutation frequency in any of these strains, either in the presence or in the absence of rat liver S9 fraction.

Table: Relative Reverse Mutation Rate – E. coli

Concentration (µg/ml)	E. coliWP2 Assay 1	E. coliWP2 Assay 2	E. coliWP2 Assay 3	E. coliWP2 uvr A Assay 1	E. coliWP2 uvr A Assay 2
Without S9
3.91	-	1.6	0.9	-	0.9
7.81	-	2.3	1.0	-	0.9
15.6	1.2	1.3	0.8	0.5	0.8
31.3	1.1	1.4	0.7	0.8	0.6
62.5	1.0	1.0	0.8	0.9	0.5
125	0.7	0.6	1.2	0.3	0.5
250	0.5	0.8	1.0	0.2	0.5
4-nitroquinoline-N-oxide	31.7	7.7	4.8	1.9	6.3
With S9
3.91	-	1.5	0.9	-	1.0
7.81	-	2.4	0.9	-	1.4
15.6	0.7	3.1	1.0	1.8	0.9
31.3	0.7	2.8	0.8	0.8	0.9
62.5	1.0	2.4	0.6	1.0	0.9
125	0.9	2.2	1.1	2.0	0.9
250	0.7	1.3	0.9	-	0.8
4-nitroquinoline-N-oxide	1.0	3.9	0.7	9.0	19.7

Table: Relative Mutation Rate – S. typhimurium TA 1535, TA 1537, TA 1538

Concentration (µg/ml)	TA 1535 Assay 1	TA 1535 Assay 2	TA 1537 Assay 1	TA 1537 Assay 2	TA 1538 Assay 1	TA 1538 Assay 2	TA 1538 Assay 3
Without S9
3.91	-	-	-	-	-	-	-
7.81	-	1.2	-	0.7	-	0.8	1.0
15.6	1.6	1.2	1.3	0	0.5	1.0	1.0
31.3	0.1	0.6	0.4	0	0	0.4	0.7
62.5	0	0	0	0	0	0	0
125	0	0	0	0	0	0	0
250	0	0	0	0	0	0	0
Sodium azide 1.7 µg	48.0	73.1	-	-	-	-	-
Benzo(a)-pyrene 6.7 µg	-	-	-	-	1.4	1.1	0.9
Neutral red 6.7 µg	-	-	1.5	1.6	-	-	-
With S9
3.91	-	-	-	-	-	-	-
7.81	-	0.9	-	0.7	-	-	0.8
15.6	2.1	1.0	2.4	0.7	1.5	-	1.0
31.3	1.4	0.9	1.3	0.9	2.1	-	0.7
62.5	1.7	0.6	1.8	0.9	1.8	-	1.0
125	1.7	1.3	2.1	0.6	1.2	-	1.1
250	1.1	0.7	2.3	0.8	1.3	-	0.9
Sodium azide 1.7 µg	19.3	78.3	-	-	-	-	-
Benzo(a)-pyrene 6.7 µg	-	-	-	-	2.4	-	10.6
Neutral red 6.7 µg	-	-	3.0	6.0	-	-	-

Table: Relative Mutation Rate – S. typhimurium TA 98, TA 100

Concentration (µg/ml)	TA 98 Assay 1	TA 98 Assay 2	TA 100 Assay 1	TA 100 Assay 2
Without S9
3.91	-	0.5	-	1.1
7.81	-	0.1	-	1.0
15.6	0.6	0	1.1	0.8
31.3	0	0	1.1	0.1
62.5	0	0	1.0	0
125	0	0	1.2	0
250	0	0	0.6	0
Benzo(a)-pyrene 6.7 µg	0.8	1.2	1.6	1.0
With S9
3.91	-	0.8	-	1.0
7.81	-	1.1	-	0.9
15.6	0.9	1.1	0.9	1.0
31.3	0.9	1.0	0.8	1.1
62.5	0.8	0.9	0.7	0.9
125	0.7	0.8	0.9	1.2
250	0.4	0.5	0.9	0.9
Benzo(a)-pyrene 6.7 µg	12.6	4.7	2.8	5.4

Applicant's summary and conclusion

Conclusions:

Interpretation of results:
negative

The purpose of this study was to determine the mutagenicity of the test substance Normal-Heptane. A reverse mutation assay was done using S. typhimurium strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100, and E. coli strains WP2 and WP2 uvr A. The strains were exposed to concentrations of 0, 3.91, 7.81, 15.6, 31.3, 62.5, 125, and 250 ug/mL for 48 -72 hrs both with and without metabolic activation. The number of revertant colonies was then counted.

No significant increases in the ratio of mutations over controls was seen. The test substance is not mutagenic in either the presence or absence of metabolic activation.

Executive summary:

The purpose of this study was to determine the mutagenicity of the test substance Normal-Heptane. A reverse mutation assay was done using S. typhimurium strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100, and E. coli strains WP2 and WP2 uvr A. The strains were exposed to concentrations of 0, 3.91, 7.81, 15.6, 31.3, 62.5, 125, and 250 ug/mL for 48 -72 hrs both with and without metabolic activation. The number of revertant colonies was then counted.

No significant increases in the ratio of mutations over controls was seen. The test substance is not mutagenic in either the presence or absence of metabolic activation.