[No public or meaningful name is available]

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:

supporting study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to valid methods and considered reliable, adequate and relevant. Limited details were available.

Data source

Reference

Reference Type:

publication

Title:

Mutagenesis Testing of Acetyl-Tributylcitrate and Epoxidized Soybean Oil

Author:

Heath J.L. and Reilly M.

Year:

1982

Bibliographic source:

1982 Poultry Science 61:2517-2519

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

without metabolic activation only

Principles of method if other than guideline:

In this case, enzyme activation was determined not to be necessary.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Soybean oil, epoxidized

EC Number:

232-391-0

EC Name:

Soybean oil, epoxidized

Cas Number:

8013-07-8

IUPAC Name:

8013-07-8

Constituent 2

Reference substance name:

Soybean oil,epoxidized

IUPAC Name:

Soybean oil,epoxidized

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): Epoxidized soybean oil; ESO
- Molecular formula (if other than submission substance): C57H98O12 (typical structure example)
- Substance type: UVCB

Method

Target gene:

histidine

Species / strain

Species / strain / cell type:

other: Salmonella typhimurium TA 98, TA 100, TA 1535, TA 1537 and TA 1538

Metabolic activation:

without

Metabolic activation system:

In these studies enzyme activation was determined not to be necessary. In the case of ESO, evidence indicates that compounds containing epoxides would be a possible carcinogen without metabolic activation (Miller and Miller, 1977; Sims, 1977)

Test concentrations with justification for top dose:

Epoxidized soybean oil (Dow Chemical Co.) (18.11 mg/2 mL dimethylsulfoxide) solutions containing 9, 18, 45, 90 and 453 µg were tested for all strains.

Controls

Positive control substance:

other: nitrofluorene solutions (1.46 mg/ 2mL dimethylsulfoxide)

Remarks:

1.5, 2.9, 4.4, 11.0, and 54.8 µg were used with tester strain TA 98; 1.5 µg with TA 100; 1.5, 2.9, and 4.4 µg with TA 1535 and 11.0 and 54.8 µg with TA 1537 and 1538.

Evaluation criteria:

The total number of revertants to histidine protrophy per plate was recorded. Chemicals were considered to have a negative response if the number of induced revertants compared to the spontaneous reversion rate of the stain was less than twofold.

Results and discussion

Test results

Species / strain:

other: Salmonella typhimurium TA 98, TA 100, TA 1535, TA 1537 and TA 1538

Metabolic activation:

without

Genotoxicity:

negative

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Mutagenesis can be grouped into two different classes, point mutation and frameshift mutations. The TA 100 and TA 1535 strains are used to detect base pair substitutions (point mutations) and strains TA 98, TA 1537 and TA 1538 to detect frameshift mutagens. The background number of revertants was low, > 25, for all strains except of TA 100. The background had none of the test compounds added. This number correlated with that reported by McCann and Ames (1976) who found that the spontaneous reversion rate was as high as 160 for control plates of TA 100 and a strain such as TA 1538 had < 30 revertants per plate. Nitrofluorene was used as a positive control and caused the TA 98 strain to have the highest number of revertants per plate. The number increased as the amount of test compound increased. The point mutation strain, TA 100 was at least as sensitive to nitrofluorene, 377 revertants, as TA 98. Tester strain TA 1537 was much less sensitive to nitrofluorene-induced mutagenesis than TA 98 and TA 100, whereas TA 1538 and TA 1535 were totally insensitive to nitrofluorene mutagenesis. Nitrofluorene thus served as a positive control in this system, because it elicited a response from both frameshift and point mutation strains.

ESO was not mutagenic in any of the tester strains used at any of the levels incorporated into the assay. The number of revertants produced after incorporation of these agentia into the system was not markedly different from control plates.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative without metabolic activation

ESBO was not mutagenic in any of the tester strains used at any of the levels incorporated into the assay. The number of revertants produced after incorporation of these agentia into the system was not markedly different from control plates.

Executive summary:

Bacterial mutagenicity testing was conducted on Epoxidized Soybean Oil (ESBO) in Salmonella typhimurium strains TA 98, TA 100, TA 1535, TA 1537 and TA 1538 without metabolic activation. In this case, enzyme activation was determined not to be necessary. ESBO was not mutagenic in any of the tester strains used at any of the levels incorporated into the assay. The number of revertants produced after incorporation of these agentia into the system was not markedly different from control plates.