Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics

Genetic toxicity: in vitro

Administrative data

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

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

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

Test material

Test material information

Constituent 1

Reference substance name:

Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics

Molecular formula:

None available - not a single isomer

IUPAC Name:

Hydrocarbons, C11-C14, n-alkanes, isoalkanes, cyclics, <2% aromatics

Method

Target gene:

N/A

Species / strain

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

Controls

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.

Results and discussion

Test results

Key result

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'.

Applicant's summary and conclusion

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.