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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:
weight of evidence
Study period:
July 12-29, 1988
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study conducted in accordance with GLP. Study material is well characterized. Protocol was si milar to OECD method of its time. Antibiotic toxicity observed at low concentrations- supporting study only.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1988
Report date:
1988

Materials and methods

Test guidelineopen allclose all
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Qualifier:
equivalent or similar to guideline
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Principles of method if other than guideline:
This study was conducted in accordance with Department 468 Standard Operating Procedure No.
0468-12-408.
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
Erythromycin
EC Number:
204-040-1
EC Name:
Erythromycin
Cas Number:
114-07-8
Molecular formula:
C37H67NO13
IUPAC Name:
6-{[4-(dimethylamino)-3-hydroxy-6-methyltetrahydro-2H-pyran-2-yl]oxy}-14-ethyl-7,12,13-trihydroxy-4-[(5-hydroxy-4-methoxy-4,6-dimethyltetrahydro-2H-pyran-2-yl)oxy]-3,5,7,9,11,13-hexamethyloxacyclotetradecane-2,10-dione (non-preferred name)

Method

Target gene:
Salmonella typhimurium histidine auxotroph bacteria of the following strains were used for the nonac tivated and rat-liver-microsome-activated tests:TA-1535, TA-1537, TA-1538, TA-98 and TA-100
Species / strain
Species / strain / cell type:
other: Salmonella typhimurium: TA1535, TA1537, TA98, TA100, TA1538
Details on mammalian cell type (if applicable):
The strains were received from Dr. Bruce Ames' laboratory, University of California, Berkeley, CA. Frozen cultures were prepared and stored at approximately -62°C. Flasks of nutrient broth were ino culated from the frozen cultures and grown overnight (approximately 18-20 hours) in a 37°C shaking water bath .
Metabolic activation:
with and without
Metabolic activation system:
S-9 mix(2.5%) from Aclor 1254-induced rat liver
Test concentrations with justification for top dose:
The study was conducted at concentrations of 0, 0.4, 0.8, 1.6, 3.1, 6.3, 12.5, 25, 50 and 100 mcg per petri plate.
Vehicle / solvent:
solvent- Dimethyl sulfoxide
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
vehicle controls used in parallel with the test material
True negative controls:
no
Positive controls:
yes
Positive control substance:
2-nitrofluorene
N-ethyl-N-nitro-N-nitrosoguanidine
other: Quinacrine Mustard (QM) and 2-aminoanthracene
Details on test system and experimental conditions:
Petri plates of Vogel Bonner Medium E agar were prepared at least 24 hours in advance of their use in accordance with Department 468 Standard Operating Procedure No. 0468-11-403.Top agar was prepared according to Department 468 Standard Operating Procedure No .0468-11-404. Each 100 ml of top agar was supplemented with 10 ml of 0.5 mM L-histidine HCl and 0.5 mM biotin

For each petri plate, 0.1 ml of Salmonella broth culture, 0.05 ml of test compound solution and 0.5 ml of S-9 mix (activated tests only) were added to 2.0 ml of molten (approximately 45°C) top agar. The top agar mixture was poured over a hardened Vogel-Bonner medium E agar petri plate and a llowed to harden. Triplicate petri plates were prepared for all test combinations. The petri plates were incubated at approximately 37°C for approximately 48 hours
Statistics:
Mean and standard deviation of the plate counts for each treatment were determined

Results and discussion

Test results
Species / strain:
other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA1538
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
Toxicity was seen at 25 mcg and higher in all strains except TA-98 and at 50 mcg and higher in TA-98
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
ABBOTT-56268 showed no mutagenic effect on Salmonella as no increases in the number of colo nies on petri plates treated with test material was seen when compared to the number of colonies on vehicle control petri plates.Toxicity, as evidenced by a reduction in the number of bacterial colonies was seen at 100 and 50 mcg for all strains, at 25 mcg for all strains except TA-98 and at 12.5 mcg for TA-1535, TA-1538 and TA-100
Remarks on result:
other: all strains/cell types tested Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative
No dose-related and reproducible increases in revertant colony frequency were observed in any tester strains at any concentration, both with and without S9. The test substance was not genotoxic in the Ames test