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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / chromosome aberration study in mammalian cells
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2002
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2002
Report date:
2002

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Version / remarks:
This study was conducted according to a method which was designed to assess the potential chromosomal mutagenicity of a test material on the metaphase chromosomes of the Chnese Hamster Lung (CHL) cell line according to the requirements of the Japanese New Chemical Substance Law (METI), OECD 473 and the updated Annex V B10 Method.
GLP compliance:
yes (incl. QA statement)
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Constituent 1
Chemical structure
Reference substance name:
3-(dimethylamino)propylurea
EC Number:
401-950-2
EC Name:
3-(dimethylamino)propylurea
Cas Number:
31506-43-1
Molecular formula:
C6H15N3O
IUPAC Name:
3-dimethylaminopropyl urea
Constituent 2
Chemical structure
Reference substance name:
1,3-bis[3-(dimethylamino)propyl]urea
EC Number:
257-861-2
EC Name:
1,3-bis[3-(dimethylamino)propyl]urea
Cas Number:
52338-87-1
Molecular formula:
C11H26N4O
IUPAC Name:
1,3-bis[3-(dimethylamino)propyl]urea
Constituent 3
Chemical structure
Reference substance name:
Urea
EC Number:
200-315-5
EC Name:
Urea
Cas Number:
57-13-6
Molecular formula:
CH4N2O
IUPAC Name:
urea
Test material form:
liquid

Method

Target gene:
The Chnese Hamster Lung (CHL) cell line, isolated by Koyama et a1 (1970) and cloned by Ishidate and Sofuni (1985), was used. The CHL cell line has an average generation time of approximately 17 hours when growing under normal experimental conditions.
Species / strain
Species / strain / cell type:
other: Chnese Hamster Lung (CHL)
Details on mammalian cell type (if applicable):
The Chnese Hamster Lung (CHL) cell line, isolated by Koyama et a1 (1970) and cloned by Ishidate and Sofuni (1985), was used. The CHL cell line has an average generation time of approximately 17 hours when growing under normal experimental conditions.
Metabolic activation:
with and without
Test concentrations with justification for top dose:
The maximum recommended dose level of 10 mM was used in all cases.
Vehicle / solvent:
DMSO was selected as the solvent because the test material was soluble at the maximum required concentration.
Controls
Positive controls:
yes
Positive control substance:
cyclophosphamide
mitomycin C
Details on test system and experimental conditions:
Duplicate cultures of Chinese Hamster Lung (CHL) cells were treated with the test material at several dose levels, together with vehicle and positive controls. Five exposure groups were used: Experiment 1 included a 6(18)-hour exposure, both with and without the addition of an induced rat liver homogenate metabolising system; Experiment 2 included a 24-hour continuous exposure, a 48-hour continuous exposure and a repeat of the 6(18)-hours exposure with metabolic
activation.
The dose levels evaluated in the main experiments were selected from a range of dose levels based on the results of a preliminary toxicity test and were in the range of 18 1.5 to 1452 pglml for all of the exposure groups.
Evaluation criteria:
In all circumstances where increases in the frequency of cells with aberrations are seen, statistical comparisons will be made with the vehicle. A positive response was recorded for a particular treatment if the % cells with aberrations, excluding gaps, markedly exceeded that seen in the concurrent control, either with or without a clear dose-relationship.
For modest increases in aberration frequency a dose response relationship is generally required and appropriate statistical tests may be applied in order to record a positive response.

Results and discussion

Test results
Key result
Species / strain:
other: Chnese Hamster Lung (CHL)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not specified
Positive controls validity:
valid
Remarks:
All the positive control chemicals induced highly significant increases in the frequency of cells with aberrations indicating the satisfactory performance of the test and of the activity of the metabolizing system.
Additional information on results:
The test material did not induce any toxicologically significant, dose-related increases in the frequency of cells with chromosome aberrations, either in the presence or absence of a liver enzyme metabolising system, or after various exposure times. The test material was therefore considered to be non-clastogenic to CHL cells in vitro.
Remarks on result:
other:
Remarks:
The test material did not induce any significant increases in the frequency of cells with aberrations in any of the exposure groups. The test material was shown to be non-toxic to CHL cells in vitro and the maximum recommended dose level of 10 rnM was used in all cases.

Applicant's summary and conclusion

Conclusions:
3-DMAPAU was shown to be non-clastogenic to CHL cells in vitro.
Executive summary:

Duplicate cultures of Chnese Hamster Lung (CHL) cells were treated with the test material at several doselevels, together with vehicle and positive controls. Five exposure groups were used: Experiment 1 includeda 6(18)-hour exposure, both with and without the addition of an induced rat liver homogenate metabolizingsystem; Experiment 2 included a 24-hour continuous exposure, a 48-hour continuous exposure and a repeatof the 6(18)-exposure with metabolic activation.The dose levels evaluated in the main experiments were selected from a range of dose levels based on theresults of a preliminary toxicity test and were in the range of 181.5 to 1562 pglml for all of the exposuregroups.The vehcle (solvent) controls gave frequencies of cells with aberrations within the range expected for theCHL cell line. All the positive control chemicals induced highly significant increases in the frequency ofcells with aberrations indicating the satisfactory performance of the test and of the activity of themetabolizing system. The test material did not induce any significant increases in the frequency of cellswith aberrations in any of the exposure groups. The test material was shown to be non-toxic to CHL cells invitro and the maximum recommended dose level of 10rnMwas used in all cases.