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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
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Study period:
17 Dec 2007 - 26 Jun 2008
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study (OECD 473)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
GLP compliance:
yes (incl. certificate)
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Methylaminoethanol
- Physical state: Liquid, colorless, clear
- Analytical purity: 99.7 %
- Lot/batch No.: fom continuous production
- Storage condition of test material: Room temperature (N2 conditions)

Method

Species / strain
Species / strain / cell type:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Metabolic activation system:
S9-mix from Aroclor 1254 treated male Sprague-Dawley rats
Test concentrations with justification for top dose:
50, 100, 200, 400, 800 µg/ml
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: culture medium (MEM: Minimal Essential Medium)
- Justification for choice of solvent/vehicle: good solubility in water
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
MEM
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: Without metabolic activation: 500 μg/mL ethyl methanesulfonate; with metabolic activation: 0.5 μg/mL cyclophosphamide
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 4 and 18 h
- Fixation time (start of exposure up to fixation or harvest of cells): 18 h and 28 h

SPINDLE INHIBITOR (cytogenetic assays): colcemid
STAIN (for cytogenetic assays): After drying, the slides were stained with 7.5% (v/v) Giemsa/Titrisol solution pH 7.2 for 10 minutes. After being rinsed twice in purified water and clarified in xylene, the slides were mounted in Corbit-Balsam.

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: 1000

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index

Statistics:
A comparison of each dose group with the negative control group was carried out using Fisher's exact test for the hypothesis of equal proportions. This test was Bonferroni-Holm corrected versus the dose groups separately for each time and was performed one-sided.

Results and discussion

Test results
Species / strain:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: The pH value of the stock solutions was adjusted to physilogical values prior to testing.
- Effects of osmolality: the osmolarity was not influenced by test substance treatment.


COMPARISON WITH HISTORICAL CONTROL DATA: yes

Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

According to the results of the present in vitro cytogenetic study, the test substance Methylaminoethanol did not lead to a relevant increase in the number of structural chromosomal aberrations incl. and excl. gaps either without S9 mix or after the addition of a metabolizing system in two experiments performed independently of each other selecting different exposure times (4 and 18 hours) and sampling times (18 and 28 hours). The types and frequencies of structural chromosome aberrations were close to the range of the concurrent negative control values at both sampling times and clearly within in the range of the historical negative control data. 

 

Under the experimental conditions chosen here, the conclusion is drawn that Methylaminoethanol is not a chromosome-damaging (clastogenic) substance under in vitro conditions using V79 cells in the absence and the presence of metabolic activation.

Applicant's summary and conclusion

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

Not chromosome-damaging
Executive summary:

A chromosome-aberration test was performed according to OECD guideline 473.

Under the experimental conditions chosen here, the conclusion is drawn that Methylaminoethanol is not a chromosome-damaging (clastogenic) substance under in vitro conditions using V79 cells in the absence and the presence of metabolic activation.