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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP guideline study with commercial sample of retinol.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Retinol 50 C
- Physical state: Yellow liquid
- Analytical purity: 47.1% in Polysorbate 20 ( UV-Spectroscopy)
- Impurities (identity and concentrations): BHZT (3.15-3.5%), BHA (0.9-1.1%).
- Purity test date: July 8, 1999
- Lot/batch No.: Lot: 23-0136
- Stability under test conditions: The stability of the test substance throughout the study period has been verified by
reanalysis .
- Storage condition of test material: Refrigerator (protected from light, N2 conditions)

Method

Target gene:
Back-mutations from tryptophan and histidin auxotrophy
Species / strain
Species / strain / cell type:
other: Salmonella typhimurium TA98, TA100, TA1535, TA1537; Escherichia coli WP2 uvrA
Metabolic activation:
with and without
Metabolic activation system:
Aroclor-induced rat liver S-9 mix
Test concentrations with justification for top dose:
50 µg - 12500 µg/plate (SPT)
20 µg - 5000 µg/plate (PIT, Salmonella strains)
50 µg - 12500 µg/plate (PIT, E. coli)
Vehicle / solvent:
Due to the limited solubility of the test substance in water, DMSO was selected as the
vehicle, which had been demonstrated to be suitable in bacterial reverse mutation tests
and for which historical control data are available .
Controls
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
Remarks:
dimethylsulfoxide
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: With S9 mix: 2 -aminoanthracene. Without S9 mix N-methyl-N'-nitro-N-nitrosoguanidine (TA1535, TA100),  4 -nitro-o-phenylenediamine (TA98), 9 -aminoacridine (TA1537), or 4 -nitro-quinoline-N-oxide (E. coli)
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation

DURATION
- Preincubation period: 20 min
- Exposure duration: 48-72h



DETERMINATION OF CYTOTOXICITY
decrease in the number of revertants
clearing or diminution of the background lawn (= reduced his- or trp- background growth)
reduction in the titer
Evaluation criteria:
The test chemical is considered positive in this assay if the following criteria are met :
A dose-related and reproducible increase in the number of revertant colonies, i .e .
about doubling of the spontaneous mutation rate in at least one tester strain either
without S-9 mix or after adding a metabolizing system .
A test substance is generally considered nonmutagenic in this test if :
The number of revertants for all tester strains were within the historical negative
control range under all experimental conditions in two experiments carried out
independently of each other .

Results and discussion

Test results
Species / strain:
other: Salmonella typhimurium TA98, TA100, TA1535, TA1537; Escherichia coli WP2 uvrA
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
other: >= 1250 µg/plate, see freetext
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
Cytotoxicity was seen occasionally from ca. 1250 to 6250 µg/plate onwards. The test substance was not completely soluble in DMSO;  precipitation of
 the test substance was found from ca. 5000 µg/plate onwards.
Remarks on result:
other: other: Salmonella typhimurium TA98, TA100, TA1535, TA1537; Escherichia coli WP2 uvrA
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion