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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
No data reported
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: This study is classified as reliable without restriction because it was carried out according to OECD TG 471.

Data source

Reference
Reference Type:
publication
Title:
Estimation of the dermal carcinogenic activity of petroleum fractions using a modified Ames assay
Author:
Blackburn GR, Deitch RA, Schreiner CA, Mehlman MA, and Mackerer CR
Year:
1984
Bibliographic source:
Cell Biol Toxicol, Vol 1(1), pp 67-80

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
not specified
Type of assay:
other: modified bacterial reverse mutation assay (modified Ames test)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Read Across to Unrefined/Acid Treated Oils

The following substances were tested:

Number 7, Solvent refined/Hydrotreated heavy naphthenic distillate, CAS # 64741-96-4/CAS # 64742-52-5.
Number 9, 10, and 11, Solvent refined/hydrotreated heavy paraffinic distillate, CAS # 64741-88-4/CAS # 64742-54-7.
Number 13: Solvent refined/dewaxed heavy paraffinic distillate, CAS # 64741-88-4/CAS # 64742-65-0.

Method

Target gene:
Not applicable.
Species / strain
Species / strain / cell type:
S. typhimurium TA 98
Details on mammalian cell type (if applicable):
Not applicable.
Additional strain / cell type characteristics:
not specified
Metabolic activation:
with
Metabolic activation system:
Aroclor 1254-induced rat or hamster liver S9
Test concentrations with justification for top dose:
50 ul
Vehicle / solvent:
dimethyl sulphoxide
Controls
Untreated negative controls:
not specified
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: benzo(a)pyrene at 5 μg/plate and 2-aminoanthracene at 2 μg/plate
Details on test system and experimental conditions:
METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: not reported
- Exposure duration: not reported
- Expression time (cells in growth medium): not reported
- Selection time (if incubation with a selection agent): not reported
- Fixation time (start of exposure up to fixation or harvest of cells): not reported

NUMBER OF REPLICATIONS: not reported

NUMBER OF CELLS EVALUATED: not reported

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index


Evaluation criteria:
Mutagenicity Index
Statistics:
No data reported.

Results and discussion

Test results
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Additional information on results:
No data reported.
Remarks on result:
other: other: Modified Ames Test using Salmonella typhimurium strain TA 98 and Aroclor 1254-induced hamster liver S-9
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

The modified assay was used to rank the test samples, and a corn oil control, for relative mutagenic activity.  The ranking correlated closely  (r=0.97) with potency ratings from previously determined carcinogenicity bioassays.  Samples subjected to solvent refining were non-carcinogenic.

In the table below, the sample number in the study report along with the study ID and mutagenicity index of each substance is listed.

Sample Number

Sample ID

CAS#

Mutagenicity Index

7

Solvent-Refined/Hydrotreated Heavy Naphthenic Distillate

64741-96-4/

64742-52-5

0

9

Solvent-Refined/Hydrotreated Heavy Paraffinic Distillate

64741-88-4/

64742-54-0

0

10

Solvent-Refined/Hydrotreated Heavy Paraffinic Distillate

64741-88-4/

64742-54-0

0

11

Solvent-Refined/Hydrotreated Heavy Paraffinic Distillate

64741-88-4/

64742-54-0

0

13

Solvent-Refined/Dewaxed Heavy Paraffinic Distillate

64741-88-4/

64742-65-0

0

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

All five solvent refined samples had mutagenicity indices of 0 and are therefore not considered positive in the AMES test for bacterial mutagenicity.
Executive summary:
In an in vitro modified Ames assay, five lubricating base oils were tested using S. typhimurium strain TA98 at concentrations of 50 micrlitres per plate. The solvent-refined samples tested were not mutagenic and had mutagenicity indices of 0. This study received a Klimisch score of 1 and is classified as reliable without restriction because it was carried out according to OECD TG 471.