Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, < 2% aromatics

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

There are no in vitro genetic toxicity data available for Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics <2% aromatics. However, data are available for structural analogues C10-C13, isoalkanes, Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics, Hydrocarbons, C12-C16, n-alkanes, isoalkanes, cyclics, <2% aromatics, Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics, and Isohexadecane. These data are read across to Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

All read across genetic toxicity tests listed below had negative results for Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics. 

Genetic Toxicity in vitro – Bacterial reverse mutation assay (OECD 471)

Genetic Toxicity in vitro – Mammalian Chromosome Aberration Test (OECD TG 473)

Genetic Toxicity in vitro - Mammalian Cell Gene Mutation Test (OECD TG 476)

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented study report equivalent or similar to OECD guideline 471: (GLP).

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

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

Species / strain / cell type:

S. typhimurium TA 102

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254-induced rat liver post-mitochondrial fraction (S-9)

Test concentrations with justification for top dose:

Test #1 (8, 40, 200, 1000, 5000 ug/plate)
Test #2 (1000, 2000, 3000, 4000, 5000 ug/plate)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: [ethanol]

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 9-aminoacridine, 2-nitrofluorene, sodium azide, glutaraldehyde

Evaluation criteria:

The test article was considered to be mutagenic if:
1) the assay was valid
2) Dunnett's test gave a significant response (<=0.01), and the data set showed a significant dose-correlation.
3) the positive responses described in 2) were reproducible.

Statistics:

The m-statistic was calculated to check that the data were Poisson-distributed, and Dunnett's test was used to compare the counts of each dose with the control. The presence or otherwise of a dose response was checked by linear regression analysis.

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results: negative

The bacterial reverse mutation test to assess the genotoxicity of the test material was negative. This finding does not warrant the classification of this test material as a genotoxin under the new Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP) or under Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.

Executive summary:

SHELLSOL D60 was examined for mutagenic activity in the bacterial reverse mutation test using histidine-requiring Salmonella typhimurium strains TA 1535, 1537, 98 and 100 and the tryptophan requiring Escherichia coli strain WP2 uvrA, in the absence and presence of a liver S9 fraction for metabolic activation.  Two tests were performed: Test #1 (8, 40, 200, 1000, 5000 ug/plate), Test #2 (1000, 2000, 3000, 4000, 5000 ug/plate).  The material was not cytotoxic.  In all cases, SHELLSOL D60 did not induce any significant changes in the number of revertant colonies, with or without metabolic activation.   It is concluded in this study that SHELLSOL D60 is not a mutagenic agent.   This finding does not warrant the classification of this test material as a genotoxin under the new Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP) or under Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: “Acceptable, well-documented study report equivalent or similar to OECD guideline 473: GLP

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

GLP compliance:

yes

Type of assay:

in vitro mammalian chromosome aberration test

Target gene:

N/A

Species / strain / cell type:

primary culture, other: human lymphocytes from two male and one female donor

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

Experiment 1 without S9 (40.36, 57.66, 82.34 ug/ml);
Experiment 1 with S9 for 3 hours followed by 17 hour recovery (490, 700, 1000 ug/ml)
Experiment 2 without S9 20h treatment 0h recovery (22.52, 28.15, 35.18 ug/ml)
Experiment 2 with S9 for 3 hours followed by 17 hours recovery (640, 800, 1000 ug/ml)
Experiment 2 with S9 for 3 hours followed by 41 hours recovery (1000 ug/ml)
Experiment 3 without S9 for 20 hours treatment and 0 hours recovery (28.15, 35.19, 43.99 ug/ml)
Experiment 3 without S9 for 44 hours and 0 hours recovery (43.99 ug/ml)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: acetone

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: 4-nitroquinoline, cyclophosphamide

Evaluation criteria:

1) a statistically significant increase in the proportion of cells with structural aberrations (excluding gaps) occurred at one or more concentrations, and 2) the proportion of cells with structural aberrations at such doses exceeded normal range, and 3) the results confirmed in the second experiment. A positive result only at delayed harvest in Experiment 2 was to be taken as evidence of clastogenicity provided criteria 1 and 2 were met. Increases in numbers of cells with gaps or increases in the proportions of cells with structural aberrations, not exceeding the normal range or occurring only at very high or very toxic concentrations, were likely to be concluded as equivocal. Full assessment of the biological importance of such increases is likely to be possible with reference to data from other test systems. Cells with exchange aberrations or cells with greater than one aberration were to be considered of particular biological significance.

Species / strain:

primary culture, other: human peripheral blood lymphocytes

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

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results: negative

The mammalian chromosomal aberration test to assess the genotoxicity of SHELLSOL D70 was negative. This finding does not warrant the classification of this test material as a genotoxin under the new Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP) or under Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.

Executive summary:

The potential of SHELLSOL D70 to cause chromosome aberration was investigated in cultured human lymphocytes with and without the metabolic activation S9 system. Negative and positive control substances were include in both experiments to confirm the activity and sensitivity of the test systems.  In the first experiment, the maximum dose levels selected for chromosome analysis were 82.34 ug/ml and 1000 ug/ml, in the absence and presence of S9 respectively.  These dose levels caused inhibitions of the mitotic index of 57% and 30% respectively.  In the second experiment, the highest concentration used for chromosome analysis were 35,18 ug/ml and 1000 ug/ml in the absence and presence of S9 respectively, these gave a reduction in the mitotic index of 52% and 12% respectively.  In both Experiments 1 and 2 in the presence of S9; and in Experiment 2 in the absence of S9 only there were no significant increases in the frequency of the cells with structural aberrations in cultures treated with SHELLSOL D70.  Following treatment in Experiment 2 in the absence of S9 there was a significant increase in the frequency of structural aberrations at the lowest dose analyzed (22.52ug/ml).  Additional doses from Experiment 1 were analyzed (19.79 and 28.25 ug/ml) to confirm whether this effect was only apparent at low concentrations.  No increase in the frequency of structural aberrations was apparent at these concentrations.  In order to further clarify the findings seen in the initial experiments, a third experiment was performed in which there were no significant increases in the frequency of cells with structural aberrations in all cultures treated with SHELLSOL D70.  Since the increase in structural aberrations seen at 22.52 ug/ml in Experiment 2 was not apparent in other experiments at similar or higher concentrations, the effect was considered to be non-reproducible and of no biological importance.  Based on these results, it is concluded that SHELLSOL D70 did not induce chromosome aberrations in cultured lymphocytes when tested to its limit of toxicity in both the absence and presence of S9.  This finding does not warrant the classification of this test material as a genotoxin under the new Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP) or under Directive 67/518/EEC for dangerous substances and Directive 1999/45/EC for preparations.

Reference 3

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 August to 21 September 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Few details on test material (no certificate of analysis)

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Deviations:

yes

Remarks:

No certificate of analysis

Principles of method if other than guideline:

Guideline principles

GLP compliance:

yes (incl. QA statement)

Type of assay:

in vitro mammalian chromosome aberration test

Target gene:

Not applicable

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Details on mammalian cell type (if applicable):

- Type and identity of media: McCoy's 5A culture medium supplemented with 10% fetal calf serum, 1% L-glutamine, and 1% penicillin and streptomycin, at about 37°C, in an atmosphere of about 5% C02 in air.
- Properly maintained: yes

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S9 from male Sprague-Dawley rats treated with Aroclor 1254

Test concentrations with justification for top dose:

Range finding assay: half-log series of concentrations of 0.0835 to 2500 µg/mL
Main experiment:
- without metabolic activation: 3.13, 6.26, 9.35 and 12.5 µg/mL with 10-h harvest and 12.5, 25, 37.5, 50 and 75 µg/mL with 20-h harvest
- with metabolic activation: 37.5, 93.8, 188, 281, 375, 563 and 750 µg/mL for 10 and 20-h harvest

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: ethanol
- Justification for choice of solvent/vehicle: test material was insoluble in water and dimethylsulfoxide. A clear and homogeneous stock solution of 201 mg/mL with ethanol could be maintained.

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: See below

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Preincubation period: 24 h
- Exposure duration: without metabolic activation: 7.25 and 17 h for 10 and 20 h assay, respectively; with metabolic activation: 2 h
- Expression time (cells in growth medium): with metabolic activation: 7.75 and 17.75 h for 20 and 10 h assay, respectively;
- Time in 0.1 µg/mL Colcemid: without metabolic activation: 1 and 0.5 h for 20 and 10 h assay, respectively; with metabolic activation: 2.5 h
- Fixation time (start of exposure up to fixation or harvest of cells): 10 h and 20 h without and without metabolic activation

STAIN (for cytogenetic assays): 5% Giemsa solution and BrdUrd (5-bromodeoxyuridine) at 10 µM

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: 100 cells for test substance; at least 25 cells for positive controls

CYTOTOXICITY: visual observations based on confluence of monolayer and floating dead cells

Evaluation criteria:

Cells were selected for good morphology and only cells with the number of centromeres equal to the modal number 21 ± 2 were analyzed.
The following factors were taken into account in the evaluation of the chromosomal aberrations data: the overall chromosomal aberration frequencies, the percentage of cells with any aberrations, the percentage of cells with more than one aberration, any evidence for increasing amounts of damage with increasing dose.
Chromatid and isochromatid gaps were not considered as they may be due to toxicity.

Statistics:

Fisher's exact test with an adjustment of multiple comparisons

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Range-finding without metabolic activation:
A very unhealthy cell monolayer, -70% reduction in the cell monolayer confluence, floating dead cells, and severe reduction in the number of visible mitotic cells were observed in the culture dosed with 25.0 µg/mL. Slight reductions in the number of visible mitotic cells and -15% reduction in the cell monolayer confluence were observed in the cultures dosed with 2.50 and 8.35 µg/mL.
Range-finding with metabolic activation:
An unhealthy cell monolayer, -85% reduction in the cell monolayer confluence, floating dead cells and debris, and severe reduction in the number of visible mitotic cells were observed in the culture dosed with 835 µg/mL. Reductions of -15% in the cell monolayer confluence were observed in the cultures dosed with 25.0 and 83.5 µg/mL.

Chromosomal aberrations assay without metabolic activation (Table 1):
In the 10 h assay, no toxicity was observed in any of the test cultures. These cultures were not analyzed for chromosomal aberrations as four dose levels were available for analysis from the 20 h assay. In the 20 h assay, an unhealthy cell monolayer, -70% and -45 % reduction in the cell monolayer confluence, floating dead cells and debris, and a severe reduction in visible mitotic cells were observed at 75.0 and 50.0 µg/mL, respectively. Toxicity was evident on the slides prepared from these cultures by the very sparse numbers of metaphases available for analysis.

Chromosomal aberration assay with metabolic activation (Tables 2 and 3):
In the 10 h assay, slight reductions in the numbers of visible mitotic cells were observed in the cultures dosed at 563 and 751 µg/mL.
In the 20 h assay, severe toxicity was exhibited on the slides prepared from the cultures dosed with 562 and 750 µg/mL by the presence of many dead cells and the sparse numbers of metaphases available for analysis. Reductions of -15% in the cell monolayer confluence were observed in the cultures dosed with 99.7, 187, 281, 375, 562, and 750 µg/mL.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Table 1: Chromosome aberrations in CHO cells fixed 20 h after exposure to MRD-90-843 without metabolic activation (results from pooled duplicate cultures)

		Number and type of aberration
		Not computed		Simple	Complex	% cells with aberrations
	Concentration (µg/mL)	Chromatid gap	Chromosome gap
Negative (vehicle)	-	7	1			0.0
Positive (Mitomycin C)	0.04	7		4	7	28.0*
Test article	25.0	15	2			0.0
	37.5	7	3	1	1	0.5
	50.0	8	1		1	0.5
	75.0	19	2	4		0.5

* Significantly greater than the pooled negative and vehicle controls, p<0.01

Table 2: Chromosome aberrations in CHO cells fixed 10 h after exposure to MRD-90-843 with metabolic activation (results from pooled duplicate cultures)

	Concentration (µg/mL)	Number and type of aberration
		Not computed		Simple	Complex	% cells with aberrations
		Chromatid gap	Chromosome gap
Negative (vehicle)	-	2				0.0
Positive (Cyclophosphamide)	25.0	1		8	13	44.0*
Test article	282	7	1			0.0
	375	3			1	0.5
	563	4			1	0.5
	751	3		3		1.0

* Significantly greater than the pooled negative and vehicle controls, p<0.01

Table 3: Chromosome aberrations in CHO cells fixed 20 h after exposure to MRD-90-843 with metabolic activation (results from pooled duplicate cultures)

	Concentration (µg/mL)	Number and type of aberration
		Not computed		Simple	Complex	% cells with aberrations
		Chromatid gap	Chromosome gap
Negative (vehicle)	-	7		1	1	0.0
Positive (Cyclophosphamide)	12.5	1		17	31	80.0*
Test article	281	15	2		1	1.0
	375	16	6	1	1	1.0
	562	3	1	1	1	1.0
	750	10		1	1	1.0

* Significantly greater than the pooled negative and vehicle controls, p<0.01

Conclusions:

Interpretation of results:
negative

MRD-90-843 was found not to increase chromosome aberrations in CHO cells with and without metabolic activation.

Executive summary:

In an in vitro chromosome aberration test, Chinese Hamster Ovary cells were exposed to MRD-90-843 at concentrations of 3.13, 6.26, 9.35 and 12.5 µg/mL for 10-h harvest and 12.5, 25, 37.5, 50 and 75 µg/mL for 20-h harvest, for 7 and 17 h, without metabolic activation and 37.5, 93.8, 188, 281, 375, 563 and 750 µg/mL for 10 and 20-h harvest, for 2 h, with metabolic activation.

Positive controls (mitomycin C without metabolic activation and cyclophosphamide with metabolic activation) induced the appropriate response. As there was no evidence of chromosome aberration induced over background, MRD-90-843 is not classified according to the criteria of Annex VI to Directive 67/548/EEC and the CLP Regulation (1272/2008).

Reference 4

Endpoint:

in vitro gene mutation study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well conducted study according to sound scientific principles.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

Deviations:

no

GLP compliance:

no

Type of assay:

mammalian cell gene mutation assay

Target gene:

TK+/ phenotype

Species / strain / cell type:

mouse lymphoma L5178Y cells

Details on mammalian cell type (if applicable):

TK+/ phenotype of L5178Y mouse lymphoma cells from subline 3.7.2C

Metabolic activation:

with and without

Metabolic activation system:

Aroclor

Test concentrations with justification for top dose:

up to was 1000 ug/mL in dimethylsulfoxide (maximum dose)

Vehicle / solvent:

dimethylsulfoxide

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

not specified

Details on test system and experimental conditions:

This assay was performed with the TK+/ phenotype of L5178Y mouse lymphoma cells from subline 3.7.2C using a minimum of eight test compound doses with and without metabolic activation by an Aroclor induced rat liver microsomal fraction. Appropriate negative, solvent, and positive controls were included with each assay. The test compound dose levels were determined by a preliminary multidose ranging study with the highest dose targeted to give approximately fifty to ninety percent inhibition of suspension cell growth depending on the solubility of the compound. C10-C13 isoalkanes achieved a homogeneous mixture at approximately 100 mg/ml in dimethylsulfoxide. The maximum dose selected for the mutagenicity test was 1000 ug/ml because it represents the limits of solubility of the test material.

Species / strain:

mouse lymphoma L5178Y cells

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

Additional information on results:

Exposure to eight graded doses of the test material in the presence of and in the absence of metabolic activation did not increase the induction of forward mutations in L5178Y mouse lymphoma cells at the T/K locus. Therefore C10-C13 isoalkanes are not considered to be mutagenic in this test system.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results: negative with and without metabolic activation

Exposure to eight graded doses of the test material in the presence of and in the absence of metabolic activation did not increase the induction of forward mutations in L5178Y mouse lymphoma cells at the T/K locus. Therefore C10-C13 isoalkanes are not considered to be mutagenic in this test system.

Executive summary:

Exposure to eight graded doses of the test material in the presence of and in the absence of metabolic activation did not increase the induction of forward mutations in L5178Y mouse lymphoma cells at the T/K locus. Therefore C10-C13 isoalkanes are not considered to be mutagenic in this test system.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

There are no data available for Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics. However, data are available for its structural analogue Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics. These data are read across to Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics <2% aromatics were non-mutagenic when tested in an in vivo cytogenicity study.

Link to relevant study records

Reference

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented study report equivalent or similar to OECD guideline 474: GLP

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Principles of method if other than guideline:

According to US EPA Guideline 84-2

GLP compliance:

yes

Type of assay:

micronucleus assay

Species:

mouse

Strain:

CD-1

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories
- Age at study initiation: ca. 8-9 weeks
- Weight at study initiation: 21-40 grams
- Assigned to test groups randomly: [no/yes, under following basis: computer generated, body weight sorting program
- Housing: individual
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum):ad libitum
- Acclimation period: 28 days


ENVIRONMENTAL CONDITIONS
- Temperature (°F): 68-76
- Humidity (%): 40-70
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: corn oil
- Amount of vehicle (if gavage or dermal): not to exceed 1ml/100 grams bw
- Purity: assumed to be 100% pure

Details on exposure:

PREPARATION OF DOSING SOLUTIONS:
The test material was weighted out and on the day of dosing, mixed with the carrier to provide stock solutions such that individual animal dose volumes did not exceed 1ml/100grams body weight. The mice were administered 1.25, 2.5, or 5.0 grams of test material/kg of body weight. Corn oil served as the carrier for the test material and was dosed at the same volume as the test material.

Duration of treatment / exposure:

Animals were treated once by oral gavage and sacrificed 24h, 48h or 72h after dosing.
Positive control animals were sacrificed 24 hours after injection

Frequency of treatment:

Animals were treated once by oral gavage and sacrificed 24h, 48h or 72h after dosing

Post exposure period:

Animals were treated once by oral gavage and sacrificed 24h, 48h or 72h after dosing

Remarks:

Doses / Concentrations:
5.0 g/kg/bw
Basis:
nominal conc.

Remarks:

Doses / Concentrations:
2.5g/kg/bw
Basis:
nominal conc.

Remarks:

Doses / Concentrations:
1.25 g/kg/bw
Basis:
nominal conc.

No. of animals per sex per dose:

30 animals (5 male; 5 female)/dose; 10/timepoint

Positive control(s):

cyclophosphamide;

- Route of administration: intraperitoneal injection
- Doses / concentrations:40 mg/kg using water as the carrier

Tissues and cell types examined:

Bone marrows were collected and extracted, smear preparations made and stained. Polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE) were scored for each animal.

Details of tissue and slide preparation:

CRITERIA FOR DOSE SELECTION: Range finding study was performed using 5.0, 2.5, and 1.0 gram of test material per kg of body weight. Two males and two females were used for each dose group. All animals survived and were sacrificed 24 hours after dosing. bome marrow was removed and slides were prepared. Slides were evaluated for percent of polychromatic erythrocytes in 1000 erythrocytes and for number of micronucleated polychromatic erythrocytes per 1000 polychromatic erythrocytes.




DETAILS OF SLIDE PREPARATION: After sacrifice, both femurs were removed. The bone marrow was then removed and suspended in fetal bovine serum. After the suspension was centrifuged, the pellet was resuspended and smears were prepared (two slides per animal). Slides were labeled with blind coding. Slides were stained using acridine orange. 1000 polychromatic erythrocytes from each animal were examined for the presence of micronuclei, and the ratio of PCE’s to NCE’s determined


METHOD OF ANALYSIS: staining color, and circular appearance and a diameter between 1/20 and 1/5 of the cell's diameter

Statistics:

Statistical analysis included calculation of means and standard deviations of the micronuclei data and a test of equality of group means by a standard one way analysis of variance at each time period. When the ANOVA was significant, comparisons of carrier control to dosed group means were made according to Duncan’s Multiple Range Test. A standard regression analysis was performed to test for a dose response. Residuals from the ANOVA were analyzed for normality by Wilk’s Criterion. The residuals were normally distributed (values were greater than 0.01 level of significance) in more than 25% of the analyses. Therefore nonparametric analysis were not performed. Sexes were analyzed separately

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

No deaths or clinical signs of toxicity were observed in animals dosed with the test material up to the maximum recommended dose of 5g/kg

Conclusions:

Interpretation of results: negative
The in vivo micronucleus assay of MRD-89-582 in mice was negative. This finding does not warrant the classification of the test material as a genotoxin under EU GHS guidelines and does not warrant classification under the EU requirements for dangerous substances and preparations.

Executive summary:

MRD-89-582 was examined for its potential to induce chromosomal damage in bone marrow erythrocytes in mice dosed by oral gavage at concentrations of 5.0,2.5, and 1.25 g/kg. Vehicle and positive control animals received corn oil and cyclophosphamide, respectively.  Bone marrow samples were collected and evaluated for micronucleus formation 24, 48 and 72 hours after dosing.  MRD-89-582 did not induce a statistically significant change in the PCE/NCE ratio in any of the test material dose groups when compared to their concurrent vehicle control groups. The positive control material (cyclophosphamide) produced a marked increase in the frequency of micronucleated PCE when compared to the concurrent vehicle control group The test material was considered to be non-genotoxic and non-clastogenic under the conditions of the test. This finding does not warrant the classification of the test material as a genotoxin under EU GHS guidelines and does not warrant classification under the EU requirements for dangerous substances and preparations guidelines.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

There are no genetic toxicity data available for Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics. However, data are available for structural analogues Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics, Hydrocarbons, C10-C13, isoalkanes, <2% aromatics, Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics, Hydrocarbons, C12-C16, n-alkanes, isoalkanes, cyclics, <2% aromatics and Isohexadecane. These data are read across to Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

In Vitro

 

In vitro gene mutation study in bacteria

In a key study (Shell, 1998), the test material (Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics) was examined for mutagenic activity in the bacterial reverse mutation test using histidine-requiring Salmonella typhimurium strains TA 1535, 1537, 98 and 100 and the tryptophan requiring Escherichia coli strain WP2 uvrA, in the absence and presence of a liver S9 fraction for metabolic activation.  Two tests were performed: Test #1 (8, 40, 200, 1000, 5000 ug/plate), Test #2 (1000, 2000, 3000, 4000, 5000 ug/plate).  The material was not cytotoxic.  In all cases, the test material did not induce any significant changes in the number of revertant colonies, with or without metabolic activation.   It is concluded in this study that the test material is not a mutagenic agent.   This finding does not warrant the classification of this test material as a genotoxin under the new Regulation (EC) 1272/2008 on classification, labeling and packaging of substances and mixtures (CLP).

In a key reverse gene mutation assay in bacteria (Poth, 1990) and in compliance with Good Laboratory Practice, strains TA98, TA100, TA1535 and TA1537 of S. typhimurium were exposed to Isohexadecane at concentrations of 10.0, 100.0, 333.3, 1000.0 and 5000.0 µg/plate in the presence and absence of mammalian metabolic activation. No cytotoxicity was observed with all the dose tested. Up to the highest investigated dose, no significant and reproducible dose-dependent increase in revertant colony numbers was obtained in any of the Salmonella typhimurium strains used (+/- S9). The positive controls induced the appropriate responses in the corresponding strains. Under the test conditions, Isohexadecane did not induce in vitro mutagenic activity in the bacterial test system in the presence and the absence of S9 activation system.

In Vitro Chromosome Aberration in Mammalian Cells

In a key OECD Guideline 473 study (Shell, 1998), the potential of the test material (Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics) to cause chromosome aberration was investigated in cultured human lymphocytes with and without the metabolic activation S9 system. Negative and positive control substances were included in both experiments to confirm the activity and sensitivity of the test systems.  In the first experiment, the maximum dose levels selected for chromosome analysis were 82.34 ug/ml and 1000 ug/ml, in the absence and presence of S9 respectively.  These dose levels caused inhibitions of the mitotic index of 57% and 30% respectively.  In the second experiment, the highest concentration used for chromosome analysis were 35,18 ug/ml and 1000 ug/ml in the absence and presence of S9 respectively, these gave a reduction in the mitotic index of 52% and 12% respectively.  In both Experiments 1 and 2 in the presence of S9; and in Experiment 2 in the absence of S9 only there were no significant increases in the frequency of the cells with structural aberrations in cultures treated with the test material.  Following treatment in Experiment 2 in the absence of S9 there was a significant increase in the frequency of structural aberrations at the lowest dose analyzed (22.52ug/ml).  Additional doses from Experiment 1 were analyzed (19.79 and 28.25 ug/ml) to confirm whether this effect was only apparent at low concentrations.  No increase in the frequency of structural aberrations was apparent at these concentrations.  In order to further clarify the findings seen in the initial experiments, a third experiment was performed in which there were no significant increases in the frequency of cells with structural aberrations in all cultures treated with the test material.  Since the increase in structural aberrations seen at 22.52 ug/ml in Experiment 2 was not apparent in other experiments at similar or higher concentrations, the effect was considered to be non-reproducible and of no biological importance.  Based on these results, it is concluded that Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics did not induce chromosome aberrations in cultured lymphocytes when tested to its limit of toxicity in both the absence and presence of S9.

 

In a key OECD Guideline 473 study (Exxon, 1991), the potential of the test material (Hydrocarbons, C12-C16, n-alkanes, isoalkanes, cyclics, <2% aromatics) to cause chromosome aberration was investigated in cultured human lymphocytes with and without the metabolic activation S9 system. Negative and positive control substance.Chinese Hamster Ovary cells were exposed to MRD-90-843 at concentrations of 3.13, 6.26, 9.35 and 12.5 µg/mL for 10-h harvest and 12.5, 25, 37.5, 50 and 75 µg/mL for 20-h harvest, for 7 and 17 h, without metabolic activation and 37.5, 93.8, 188, 281, 375, 563 and 750 µg/mL for 10 and 20-h harvest, for 2 h, with metabolic activation. Positive controls (mitomycin C without metabolic activation and cyclophosphamide with metabolic activation) induced the appropriate response. As there was no evidence of chromosome aberration induced over background, MRD-90-843 is not classified according to the CLP Regulation (1272/2008).

In vitro Gene Mutation study in Mammalian Cells

In a key study (Chevron, 1982), exposure to eight graded doses of the test material (Hydrocarbons, C10-C13, isoalkanes) in the presence of and in the absence of metabolic activation did not increase the induction of forward mutations in L5178Y mouse lymphoma cells at the T/K locus. Therefore C10-C13 isoalkanes are not considered to be mutagenic in this test system.

 

In Vivo

In a key cytogenicity/ erythrocyte micronucleus study (ExxonMobil, 1991), the test material (Hydrocarbons, C10-C13, n-alkanes, isoalkanes, cyclics, <2% aromatics) was examined for its potential to induce chromosomal damage in bone marrow erythrocytes in mice dosed by oral gavage at concentrations of 5.0,2.5, and 1.25 g/kg. Vehicle and positive control animals received corn oil and cyclophosphamide, respectively.  Bone marrow samples were collected and evaluated for micronucleus formation 24, 48 and 72 hours after dosing.  The test material did not induce a statistically significant change in the PCE/NCE ratio in any of the test material dose groups when compared to their concurrent vehicle control groups. The positive control material (cyclophosphamide) produced a marked increase in the frequency of micronucleated PCE when compared to the concurrent vehicle control group. The test material was considered to be non-genotoxic and non-clastogenic under the conditions of the test. This finding does not warrant the classification of the test material as a genotoxin under EU GHS guidelines and does not warrant classification under the EU requirements for dangerous substances and preparations guidelines.

Justification for classification or non-classification

The negative results using in vitro and in vivo genotoxicity assays from structural analogues do not warrant the classification of Hydrocarbons, C12-C15, n-alkanes, isoalkanes, cyclics, <2% aromatics as genotoxic under Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures (CLP).