Hydrotreated mixture of middle straight-run gas oil and soybean oil

Genetic toxicity: in vitro

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Modified version of a standard Ames test, good experimental detail, suitable for assessment

Data source

Reference

Reference Type:

publication

Title:

Evaluation of the Genetic Toxicity of Middle Distillate Fuels

Author:

R.H. McKee, M.A. Amoruso, J.J. Freeman and R.T. Przygoda

Year:

1994

Bibliographic source:

Environmental and Molecular Mutagenesis 23:234-238 (1994)

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

[1] extraction step designed to concentrate possible mutagenic aromatic compounds. [2] use of S-9 at 8x recommended concentration. [3] Use of only 1 strain Salmonella Typhimurium (TA 98) most sensitive to complex mixture of PAHs

Principles of method if other than guideline:

Method of Blackburn: Ames test modified to optimise detection of mutagenic PAHs in petroleum-based oils (see derivation of standard Ames test)

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Reference

Name:

Unnamed

Type:

Constituent

Type:

Constituent

Type:

Constituent

Method

Target gene:

Not applicable

Species / strain

Species / strain / cell type:

bacteria, other: Salmonella Typhimurium TA 98

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with

Metabolic activation system:

Aroclor-induced hamster S9 used at 8x standard Ames test concentration, with pre-incubation

Test concentrations with justification for top dose:

DMSO extracts: 5, 10, 15, 20, 30, 40, 50, 60 (represents extractable material from approx. 0.8-9.6 mg of the test substance)
Cyclohexane extracts: 1, 5, 10, 25, 50 uL/plate (represents extractable material from approx. 0.16-8 mg of the test substance)

Vehicle / solvent:

Extraction solvent: DMSO and cyclohexane

Controls

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Results and discussion

Test results

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with

Genotoxicity:

ambiguous

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Observations:
DMSO extract: tested at 5-60 ul/plate, toxic at 50 and 60
ul/plate. Revertant count doubled (2.2x) at 60 ul/plate
compared with solvent control, but no clear dose-response
relationship. Mutagenic index calculated as 1.3
revertants/ul. Result concluded equivocal.

Remarks on result:

other: strain/cell type: bacteria

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
ambiguous with metabolic activation

It is expected based on the results of the analogus substance Renewable Diesel has weak genotoxic potential in vitro, which is likely to be attributable to the content of aromatics, particularly polycyclic aromatic hydrocarbons (PAHs).