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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro DNA damage and/or repair study
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1988
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Equivalent or similar to OECD TG 479.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report Date:
1987

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 479 (Genetic Toxicology: In Vitro Sister Chromatid Exchange Assay in Mammalian Cells)
GLP compliance:
not specified
Type of assay:
sister chromatid exchange assay in mammalian cells

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Hydrodesulfurized kerosene

Method

Species / strain
Species / strain / cell type:
Chinese hamster Ovary (CHO)
Metabolic activation:
with and without
Metabolic activation system:
S-9
Test concentrations with justification for top dose:
0, 0.007, 0.013, 0.025, 0.05 uL/mL (without activation)
0, 0.05, 0.1, 0.2, 0.4 uL/mL (with activation)
Vehicle / solvent:
Acetone
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
acetone
True negative controls:
yes
Positive controls:
yes
Positive control substance:
triethylenemelamine
Details on test system and experimental conditions:
For the SCE assay CHO cells were seeded in duplicate for each treatment condition and were incubated at 37°C in a humidified atmosphere for 16 to 24 hours. Treatment was carried out by refeeding two complete sets of flasks with complete medium for the non activation study or with S-9 reaction mixture for the activated study to which was added 50 µl of dosing solution of test control or article in solvent or solvent alone. In the non activation study the cells were exposed for about 25 hours. At the end of the treatment period, the treatment medium was removed, the cells rinsed and then exposed to 0.01mM BrdUrd and colcemid (0.1 µg/ml) for a further 2 hours. In the activation study exposure was for 2 hours. After the exposure period, the treatment medium was removed, the cells were washed re-fed with medium containing BrdUrd and then incubated for a further 26 hours. Colcemid was added for the last 2 hours of incubation.For activated and non activated assays metaphase cells were harvested 2 hours after addition of colcemid. Cells were collected and fixed and stored until slides were prepared.
Evaluation criteria:
Slides were coded and scored without regard to treatment group. Only cells with 20 ±2 centromeres were selected for evaluation of SCEs. A total of 4 doses were scored including the highest test article dose where sufficient second-division metaphase cells wee available. SCEs were scored in 25 cells from each duplicate culture to make up a total of 50 cells per treatment. The percentage of cells in first (M1), second (M2) or third division (M3) metaphase was also recorded for a total of 100 metaphase cells scored. TEM was used as positive control in the non activated assay at a concentration of 0.025 µg/ml. CP was used in the activation assay at a concentration of 2.5 µg/ml.
Statistics:
The test material was considered positive if it induced a doubling in SCE frequency over the solvent control at a minimum of three consecutive dose levels or if a dose responsive and statistically significant increase was observed over a minimum of three dose levels.

Results and discussion

Test results
Species / strain:
Chinese hamster Ovary (CHO)
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
Additional information on results:
The test material was soluble at all concentrations tested. The study in both the presence and absence of S9 was repeated since there was a poor metaphase cell yield. The responses to the positive and negative control materials fulfilled the requirements for the assays. The test material did not cause an increase in SCEs in the absence of exogenous activation. The test material did cause a increase in SCEs at two non adjacent doses (0.05 and 0.4 uL/mL) in the activation assay. However, the increased activity was only seen in one of two treatment flasks. These increases appeared to be random and of no biological significance. It was concluded that the test material was negative in the SCE assay.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

It was concluded that the test material was negative in the SCE assay.
Executive summary:

It was concluded that the test material was negative in the SCE assay.