Alkanes, C16-47, branched and linear

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

No key or supporting data is available for the registered substance. However, key data is available from a structurally related substance, C18-C50 branched, cyclic and linear hydrocarbons – Distillates (CAS# 848301-69-9) and is presented below:

In vitro:
- Gene mutation (Bacterial reverse mutation assay / Ames test): negative with and without activation in Salmonella typhimurium strains (TA 98, 100, 1535, 1537) and Escherichia coli WP2uvrA (OECD 471).
- Cytogenicity in mammalian cells: negative with and without activation in human lymphocytes (OECD Draft Guideline 487).
- Cytogenicity in mammalian cells: negative with and without activation in human lymphocytes (OECD 473).

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

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 source

Key result

Species / strain:

other: Salmonella typhimurium strains TA100 and Escherichia coli strains WP2uvrA-

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(> 5000 µg/plate)

Vehicle controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

other: Salmonella typhimurium strains TA100 and Escherichia coli strains WP2uvrA-

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(> 5000 µg/plate)

Vehicle controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

other: Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100 and Escherichia coli strains WP2uvrA-

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(> 5000 µg/plate)

Vehicle controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

other: Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100 and Escherichia coli strains WP2uvrA-

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

(> 5000 µg/plate)

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Observations:
Solvent control plates gave counts of revertant colonies within the normal range. All positive control chemicals gave increases in revertants, either with or without the metabolising system as appropriate, within expected ranges. No statistically significant increase in the numbers of revertant colonies was recorded for any of the bacterial strains with any dose of the substance, either with or without metabolic activation. The substance was found to be non-mutagenic under the conditions of this test.

Remarks on result:

other: other: preliminary test

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results:
negative with metabolic activation Not classified with regards to potential germ cell mutagenicity according to Regulation (EC) No) 1272/2008
negative without metabolic activation Not classified with regards to potential germ cell mutagenicity according to Regulation (EC) No) 1272/2008

non-mutagenic (with and without S9)

Executive summary:

The substance 'Distillates (Fischer-Tropsch), heavy, C18-50, branched, cyclic and linear' has been tested in a bacterial mutagenicity study according to OECD 471 and under GLP using Salmonella typhimurium strains TA 98, TA 100, TA 1535, TA 1537 and Escherichia coli WP2uvrA. The test material was dissolved in tetrahydrofuran at concentrations up to 5000 µg/plate. Appropriate solvent and positive controls were included and gave expected results. No toxicity to bacterial cells was observed. No significant increase in the number of revertants was observed at any concentration with and without metabolic activation in any of the strains tested. The results were confirmed in a repeat experiment; both experiments used the direct plate incorporation method.

The test material was considered to be non-mutagenic under the conditions of the tests both with and without S9.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

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 source

Key result

Species / strain:

lymphocytes: Human

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Remarks:

Refer to information on results and attached tables.

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: There was no significant change in pH when the test material was dosed into media.
- Effects of osmolality: The osmalality did not increase by more than 50 mOsm.
- Evaporation from medium: Not applicable.
- Water solubility: Not applicable, test material dissolved in THF
- Precipitation:

RANGE-FINDING/SCREENING STUDIES:
Preliminary Toxicity Test

The dose range for the Preliminary Toxicity Test was 9.77 to 2500 µg/ml. The maximum dose was the maximum practical dose level. A precipitate of the test material was observed in the parallel blood-free cultures at the end of exposure, at and above 39.06 µg/ml, in the 4-hour exposure group in the presence of S9 and in the 24 hour exposure group in the absence of S9. In the 4-hour exposure group in the absence of S9 precipitate was observed at and above 78.13 µg/ml. The precipitate became greasy/oily at and above 625 µg/ml in the 4-hour exposure groups and at and above 312.5 in the 24-hour continuous exposure group.
Microscopic assessment of the slides prepared from the exposed cultures showed that metaphase cells were present up to 2500 µg/ml in all three of the exposure groups. The mitotic index data are presented in the attached Appendix 1 (5) and (6). The test material induced no clear evidence of toxicity in any of the exposure groups.
The selection of the maximum dose level for the main experiments was based on the onset of precipitate in all exposure groups and was limited to a maximum dose level of 80 µg/ml.

EXPERIMENT 1:
The dose levels of the controls and the test material are given in the table below:

Group Final concentration of Distillates (Fischer-Tropsch), heavy, C18-50-branched, cyclic and linear (µg/ml)
4(20)-hour without S9 0*, 2.5, 5, 10, 20*, 40*, 80*, MMC 0.4*
4(20)-hour with S9 0*, 2.5, 5, 10, 20*, 40*, 80*, CP 5*

The qualitative assessment of the slides determined that the toxicity was similar to that observed in the Preliminary Toxicity Test and that there were metaphases suitable for scoring present up to the maximum test material dose level of 80 µg/ml in both the absence and presence of metabolic activation (S9).
The results of the mitotic indices (MI) from the cultures after their respective treatments are presented in the attached Form 1, Appendix 2. These data show that an approximate 50% growth inhibition was not achieved in either the absence or presence of S9.
A greasy/oily precipitate of the test material was observed at the end of the treatment period at 80 µg/ml in the absence of S9 only.
The maximum dose level selected for metaphase analysis was based on the lowest precipitating dose level as seen in the preliminary toxicity test in both the absence and presence of S9, and was the maximum dose level investigated of 80 µg/ml.
The chromosome aberration data are given in the attached Form 1, Appendix 2. All of the vehicle control cultures had frequencies of cells with chromosome aberrations within the expected range. The positive control materials induced statistically significant increases in the frequency of cells with aberrations. The metabolic activation system was therefore shown to be functional and the test method itself was operating as expected.
The test material did not induce any statistically significant increases in the frequency of cells with aberrations in either the absence or presence of metabolic activation (S9).
The polyploid cell frequency data are given in the attached Form 1, Appendix 2. The test material did not induce a statistically significant increase in the numbers of polyploid cells at any dose level in either of the exposure groups.


EXPERIMENT 2:
The dose levels of the controls and the test material are given in the following table:

Group Final concentration of Distillates (Fischer-Tropsch), heavy, C18-50-branched, cyclic and linear (µg/ml)
24-hour without S9 0*, 2.5, 5, 10, 20*, 40*, 80*, MMC 0.2*
4(20)-hour with S9 0*, 2.5, 5, 10, 20*, 40*, 80*, CP 5*

The qualitative assessment of the slides determined that there were metaphases suitable for scoring present up to the maximum test material dose level of 80 µg/ml in both the absence and presence of S9.
The results of the mitotic indices (MI) from the cultures after their respective treatments are presented in the attached Form 2, Appendix 2. These data show that an approximate 50% growth inhibition was not achieved in either the absence or presence of S9.
A cloudy precipitate of the test material was observed at the end of the treatment period at and above 40 µg/ml in the absence of S9 which formed a greasy/oily precipitate at 80 µg/ml. No precipitate was observed at any dose level in the presence of S9.
The maximum dose level selected for metaphase analysis was the same as in Experiment 1, and was the maximum dose level tested (80 µg/ml).
The chromosome aberration data are given in the attached Form 2, Appendix 2. All of the vehicle control cultures had frequencies of cells with chromosome aberrations within the expected range. The positive control materials induced statistically significant increases in the frequency of cells with aberrations. The metabolic activation system was therefore shown to be functional and the test method itself was operating as expected.
The test material did not induce any statistically significant increases in the frequency of cells with chromosome aberrations in either the absence or presence of metabolic activation.
The polyploid cell frequency data are given in the attached Form 2, Appendix 2. The test material did not induce a significant increase in the numbers of polyploid cells at any dose level in either of the exposure groups.

Remarks on result:

other: strain/cell type:

Remarks:

Migrated from field 'Test system'.

Due to the nature and format of the results, please refer to the attached tables and dose response curves

Preliminary Toxicity Test

The dose range for the Preliminary Toxicity Test was 9.77 to 2500 µg/ml. The maximum dose was the maximum practical dose level.  A precipitate of the test material was observed in the parallel blood-free cultures at the end of exposure, at and above 39.06 µg/ml, in the 4-hour exposure group in the presence of S9 and in the 24 -hour exposure group in the absence of S9. In the 4-hour exposure group in the absence of S9 precipitate was observed at and above 78.13 µg/ml. The precipitate became greasy/oily at and above 625 µg/ml in the 4-hour exposure groups and at and above 312.5 in the 24-hour continuous exposure group.

Microscopic assessment of the slides prepared from the exposed cultures showed that metaphase cells were present up to 2500 µg/ml in all three of the exposure groups. The mitotic index data are presented in the attached Appendix 1 (5) and (6). The test material induced no clear evidence of toxicity in any of the exposure groups.

The selection of the maximum dose level for the main experiments was based on the onset of precipitate in all exposure groups and was limited to a maximum dose level of 80 µg/ml.

Chromosome Aberration Test – Experiment 1

The dose levels of the controls and the test material are given in the table below:

Group	Final concentration of Distillates (Fischer-Tropsch), heavy, C18-50-branched, cyclic and linear) (µg/ml)
4(20)-hour without S9	0*, 2.5, 5, 10, 20*, 40*, 80*, MMC0.4*
4(20)-hour with S9	0*, 2.5, 5, 10, 20*, 40*, 80*, CP5*

The qualitative assessment of the slides determined that the toxicity was similar to that observed in the Preliminary Toxicity Test and that there were metaphases suitable for scoring present up to the maximum test material dose level of 80 µg/ml in both the absence and presence of metabolic activation (S9). The results of the mitotic indices (MI) from the cultures after their respective treatments are presented in the attached Form 1, Appendix 2.  These data show that an approximate 50% growth inhibition was not achieved in either the absence or presence of S9. A greasy/oily precipitate of the test material was observed at the end of the treatment period at 80 µg/ml in the absence of S9 only. The maximum dose level selected for metaphase analysis was based on the lowest precipitating dose level as seen in the preliminary toxicity test in both the absence and presence of S9, and was the maximum dose level investigated of 80 µg/ml.

The chromosome aberration data are given in the attached Form 1, Appendix 2. All of the vehicle control cultures had frequencies of cells with chromosome aberrations within the expected range. The positive control materials induced statistically significant increases in the frequency of cells with aberrations. The metabolic activation system was therefore shown to be functional and the test method itself was operating as expected.

The test material did not induce any statistically significant increases in the frequency of cells with aberrations in either the absence or presence of metabolic activation (S9).

The polyploid cell frequency data are given in the attached Form 1, Appendix 2. The test material did not induce a statistically significant increase in the numbers of polyploid cells at any dose level in either of the exposure groups.

 Chromosome Aberration Test - Experiment 2

The dose levels of the controls and the test material are given in the following table:

Group	Final concentration of Distillates (Fischer-Tropsch), heavy, C18-50-branched, cyclic and linear (µg/ml)
24-hour without S9	0*, 2.5, 5, 10, 20*, 40*, 80*, MMC0.2*
4(20)-hour with S9	0*, 2.5, 5, 10, 20*, 40*, 80*, CP5*

The qualitative assessment of the slides determined that there were metaphases suitable for scoring present up to the maximum test material dose level of 80 µg/ml in both the absence and presence of S9.

The results of the mitotic indices (MI) from the cultures after their respective treatments are presented in the attached Form 2, Appendix 2. These data show that an approximate 50% growth inhibition was not achieved in either the absence or presence of S9.

A cloudy precipitate of the test material was observed at the end of the treatment period at and above 40 µg/ml in the absence of S9 which formed a greasy/oily precipitate at 80 µg/ml. No precipitate was observed at any dose level in the presence of S9.

The maximum dose level selected for metaphase analysis was the same as in Experiment 1, and was the maximum dose level tested (80 µg/ml). The chromosome aberration data are given in the attached Form 2, Appendix 2.  All of the vehicle control cultures had frequencies of cells with chromosome aberrations within the expected range. The positive control materials induced statistically significant increases in the frequency of cells with aberrations. The metabolic activation system was therefore shown to be functional and the test method itself was operating as expected.

The test material did not induce any statistically significant increases in the frequency of cells with chromosome aberrations in either the absence or presence of metabolic activation.

The polyploid cell frequency data are given in the attached Form 2, Appendix 2. The test material did not induce a significant increase in the numbers of polyploid cells at any dose level in either of the exposure groups.

CONCLUSION

The test material did not induce a statistically significant increase in the frequency of cells with chromosome aberrations in either the absence or presence of a liver enzyme metabolising system in either of two separate experiments. The test material was therefore considered to be non-clastogenic to human lymphocytes in vitro.

*Dose levels selected for metaphase analysis

MMC= Mitomycin C

CP= Cyclophosphamide

Conclusions:

Interpretation of results: negative

The test material did not induce a statistically significant increase in the frequency of cells with chromosome aberrations in either the absence or presence of a liver enzyme metabolising system in either of two separate experiments. The test material was therefore considered to be non-clastogenic to human lymphocytes in vitro.

Executive summary:

Introduction. 

This report describes the results of an in vitro study for the detection of structural chromosomal aberrations in cultured mammalian cells. It supplements microbial systems insofar as it identifies potential mutagens that produce chromosomal aberrations rather than gene mutations (Scott et al, 1990). The method used followed that described in the OECD Guidelines for Testing of Chemicals (1997) No. 473 "Genetic Toxicology: Chromosome Aberration Test" and Method B10 of Commission Regulation (EC) No. 440/2008 of 30 May 2008. The study design also meets the requirements of the UK Department of Health Guidelines for Testing of Chemicals for Mutagenicity and is acceptable to the Japanese New Chemical Substance Law (METI).

Methods. 

Duplicate cultures of human lymphocytes, treated with the test material ‘Distillates (Fischer-Tropsch), heavy, C18-50 - branched, cyclic and linear’, were evaluated for chromosome aberrations at three dose levels, together with vehicle and positive controls. Four treatment conditions were used for the study, i.e. In Experiment 1, 4 hours in the presence of an induced rat liver homogenate metabolising system (S9), at a 2% final concentration with cell harvest after a 20-hour expression period and a 4 hours exposure in the absence of metabolic activation (S9) with a 20-hour expression period. In Experiment 2, the 4 hours exposure with addition of S9 was repeated (using a 1% final S9 concentration), whilst in the absence of metabolic activation the exposure time was increased to 24 hours.

The dose levels used in the experiments were selected using data from the preliminary toxicity test and were as follows:

Group	Final concentration of test material(µg/ml)
4(20)-hour without S9	2.5, 5, 10, 20, 40, 80
4(20)-hour with S9 (2%)	2.5, 5, 10, 20, 40, 80
24-hour without S9	2.5, 5, 10, 20, 40, 80
4(20)-hour with S9 (1%)	2.5, 5, 10, 20, 40, 80

Results. 

All vehicle (solvent) controls had frequencies of cells with aberrations within the range expected for normal human lymphocytes.

All the positive control materials induced statistically significant increases in the frequency of cells with aberrations indicating the satisfactory performance of the test and of the activity of the metabolising system.

The test material was generally considered to be non-toxic and did not induce any statistically significant increases in the frequency of cells with aberrations, in any of the exposure conditions, using a dose range that included a dose level that was limited by the onset of precipitate.

Conclusion. 

The test material was considered to be non-clastogenic to human lymphocytes in vitro.

Reference 3

Endpoint:

in vitro cytogenicity / micronucleus study

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

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 source

Key result

Species / strain:

lymphocytes: human

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

>625µg/mL

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Remarks:

Precipitating concentration>=156.25µg/mL with S9

Vehicle controls validity:

valid

Positive controls validity:

valid

Key result

Species / strain:

lymphocytes: human

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

2500µg/mL

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Remarks:

Precipitating concentrations: >640µg/ mL

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: other: Preliminary

Remarks:

Migrated from field 'Test system'.

Preliminary Toxicity Test

The dose range for the Preliminary Toxicity Test was 9.75 to 2500µg/mL. The maximum dose was based on the maximum practical dose level. An cloudy precipitate of the test material was observed in the parallel blood-free cultures at the the end of the exposure at and above 78.1µg/mL in both exposure groups without S9 and at and above 156.25µg/mL in the presence of S9. The precipitate was generally observed to form a greasy/ oily layer at and above 625µg/mL in the whole blood cultures, though there was some variation between exposure groups, and it was considered that overall the maximum exposure to the cells was occurring at about this dose level. Microscopic assessment of the slides prepared from the cultures showed that binucleate cells were present at up to 2500µg/mL in all three of the exposure groups. The CBPI data are presented in Table 1.

The test material induced no evidence of toxicity in any of the exposure groups.

Micronucleus Test- Experiment 1

The dose levels of the controls and the test material selected for binucleate analysis were 0, 160, 320 and 640 µg/mL in Groups 4(16) hour without S9 and 4(16) hour with S9.

The qualitative assessment of the slides determined that the toxicity was similar to that observed in the Preliminary Toxicity Test and that there were binucleate cells suitable for scoring at the maximum dose level of the test material investigated, 640µg/L in the absence and presence of S9. Precipitate observations taken in the Preliminary Toxicity Test were considered to be representative for the study.

The CBPI data are given in Table 2. They confirm the qualitative observations in that no marked dose-related inhibition of CBPI was observed in either the absence or presence of S9. The maximum dose level selected for analysis of binucleate cells was the maximum dose level investigated (640µg/mL).

The micronucleus frequency data are given in Table 4 and 5. The vehicle control cultures had frequencies of cells with micronuclei within the expected range. The positive cntrol materials induced statistically significant increases in the frequency of cells with micronuclei. The metabolic activation system was therefore shown to be functional and the test material itself was operating as expected.

The test material did not induce any statistically significant increases in the frequency of cells with micronuclei, in either the absence or presence of metabolic activation.

Experiment 2

The dose levels of the controls and the test material selected for binucleate analysis were 0, 160, 320 and 640 µg/mL in Groups 20- hour without S9 and 4(16)- hour with S9.

The qualitative assessment of the slides determined that there were binucleate cells suitable for scoring at the maximum test material dose level investigated, 640µg/mL, in both the absence and presence of S9. Precipitate was observed at and above 80µg/mL, in the absence of S9, and at and above 160µg/mL in the presence of S9.

The CBPI data are given in Table 3. They confirm the qualitative obsrevations in that there was no dose-related inhibition of CBPI observed in eithe the absence or presence of S9. The maximum dose level selected for binucleate cell analysis was the maximum dose level investiagtes (640µg/mL).

The micronucleus data are given in Table 6 and 7. The vehicle control cultures had frequencies of cells with micronuclei within the expected range. The positive control materials induced statistically significant increases in the frequency of cells with micronuclei. The metabolic activation system was therefore shown to be functional and the test method itself was operating as expected.

The test matertial did not induce any statistically significant increases in the frequency of cells with micronuclei, in either the absence or presence of metabolic acivation system.

Conclusions:

Interpretation of results:
negative without metabolic activation Not classified with regards to potential germ cell mutagenicity according to Regulation (EC) No) 1272/2008
negative with metabolic activation Not classified with regards to potential germ cell mutagenicity according to Regulation (EC) No) 1272/2008

non-clastogenic and non-aneugenic to human lymphocytes in vitro

Executive summary:

An in vitro micronucleus study has been conducted using the substance ‘Distillates (Fischer-Tropsch), heavy, C18-50 - branched, cyclic and linear’ following OECD draft guideline 487 and conducted under GLP conditions. No increase in the incidence of micronuclei was observed in duplicate cultures of human lymphocytes at any concentration in either the initial experiment (4 hour exposure, 16 hour expression, with and without metabolic activation) or the repeat experiment (20 hour exposure without metabolic activation; 4 hour exposure, 16 hour expression, with metabolic activation). No test material induced toxicity was observed. The test material was dissolved in acetone, and the maximum concentration tested was 2500 µg/plate; higher concentrations could not be tested due to difficulties in formulating the test material in the vehicle. The vehicle controls had frequencies of cells with micronuclei within the range expected for normal human lymphocytes, and appropriate positive controls were concluded and induced significant increases in the number of cells with micronuclei.

It was concluded that the test material is non-clastogenic and non-aneugenic to human lymphocytes in vitro.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

No key or supporting data is available for the registered substance. However, key data is available from a structurally related substance, C18-C50 branched, cyclic and linear hydrocarbons – Distillates (CAS# 848301-69-9) and is presented below:

In vivo:

- Cytogenicity: negative in Mammalian Bone Marrow Chromosome Aberration Test (OECD 474/EU B.11)

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

No key or supporting data is available for the registered . However, key data is available from a structurally related substance, C18-C50 branched, cyclic and linear hydrocarbons – Distillates (CAS# 848301-69-9) and is presented below:

C18-C50 branched, cyclic and linear hydrocarbons – Distillates (CAS# 848301-69 -9) has been tested in a bacterial mutagenicity study according to OECD 471 and under GLP using Salmonella typhimurium strains TA 98, TA 100, TA 1535, TA 1537 and Escherichia coli WP2uvrA. The test material was dissolved in tetrahydrofuran at

concentrations up to 5000 µg/plate. Appropriate solvent and positive controls were included and gave expected results. No toxicity to bacterial cells was observed. No significant increase in the number of revertants was observed at any concentration with and without metabolic activation in any of the strains tested. The results were confirmed in a repeat experiment; both experiments used the direct plate incorporation method.

An in vitro micronucleus study has been conducted using GTL Base Oil Distillates following OECD draft guideline 487 and conducted under GLP conditions. No increase in the incidence of micronuclei was observed in duplicate cultures of human lymphocytes at any concentration in either the initial experiment (4 hour exposure, 16 hour expression, with and without metabolic activation) or the repeat experiment (20 hour exposure without metabolic activation; 4 hour exposure, 16 hour expression, with metabolic activation). No test material induced toxicity was observed. The test material was dissolved in acetone, and the maximum concentration tested was 2500 µg/plate; higher concentrations could not be tested due to difficulties in formulating the test material in the vehicle. The vehicle controls had frequencies of cells with micronuclei within the range expected for normal human lymphocytes, and appropriate positive controls were concluded and induced significant increases in the number of cells with micronuclei. It was concluded that the test material is non-clastogenic and non-aneugenic to human lymphocytes in vitro.

Further evidence of the lack of effects on chromosomes in vitro was obtained when the substance was tested according to OECD 473 and under GLP. No statistically significant increase in the frequency of cells with chromosome aberrations was observed in either the initial or the repeat experiment when tested with and without metabolic activation up to a dose level that was limited by the onset of precipitate. Appropriate solvent and positive controls were included and gave expected results.

Moreover, in vivo data is available from an in vivo chromosome aberration study on C18 -C50 branched, cyclic and linear hydrocarbons - Distillates (CAS# 848301 -69 -9) conducted according to OECD 475 and under GLP:

The test was conducted using the oral route in groups of seven rats at the maximum recommended dose (MRD) 2000 mg/kg for the 24-hour and 48-hour time points, with 1000 and 500 mg/kg as the lower dose levels. Animals were killed 24 or 48 hours later, the bone marrow was extracted, processed and slide preparations made and stained. Bone marrow cells were scored for the presence of chromosome aberrations.

 

There were no premature deaths seen in any of the test item dose groups. No clinical signs were observed in animals dosed with the test item at any dose level. No marked decreases in the mitotic index mean value were observed in any of the test item dose groups when compared to the vehicle control group. There was no evidence of a statistically significant increase in the incidence of cells with chromosome aberrations excluding gaps in animals dosed with the test item, when the dose groups were compared to the vehicle control group. 

 

The test item did not induce any statistically significant increases in the numbers of polyploid cells at any dose level in any of the exposure groups and it did not induce any significant or dose-related increases in the frequency of chromosome aberrations. The test item was considered to be non-clastogenic to rat bone marrow cells in vivo.

Justification for classification or non-classification

Based on the available read across in vitro and in vivo data, the registered substance is not genotoxic and does not require classification according to Regulation 1272/2008/EC.