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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
Study period:
Not reported
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Good quality study, limited reporing. Similar to procedure described in OECD Test Guideline 471 (bacterial reverse mutation test) but compliance to current guidelines would have required an additional bacterial strain to detect certain oxidising mutagens and cross-linking agents (i.e. TA102 and/or E.coli).

Data source

Reference
Reference Type:
publication
Title:
Salmonella mutagenicity tests: II. Results from the testing of 270 chemicals
Author:
Mortelmans K, Haworth S, Lawlor T, Speck W, Tainer B and Zeiger E
Year:
1986
Bibliographic source:
Environmental Mutagenesis 8 (Suppl. 7), p. 1-119

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Similar procedure to OECD guideline 471:bacterial reverse mutation test, although only four strains of bacteria were tested. Current guidelines recommend an additional bacterial strain is tested to detect certain oxidising mutagens and cross-linking agents (i.e. TA102 and/or E.coli).
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
not specified
Details on test material:
- Name of test material (as cited in study report): palladium (II) chloride
- Substance type: no data
- Physical state: no data
- Analytical purity: no data
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: no data
- Isomers composition: no data
- Purity test date: no data
- Lot/batch No.: no data
- Expiration date of the lot/batch: no data
- Stability under test conditions: no data
- Storage condition of test material: no data
- Other: Supplier: Fisher Scientific

Method

Target gene:
Histidine
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Metabolic activation system:
Aroclor 1254-induced rat and hamster liver S-9 (10%)
Test concentrations with justification for top dose:
0
0.3 ug/plate (without metabolic activation only)
1.0 ug/plate (without metabolic activation only)
3.0 ug/plate (with and without metabolic activation)
10.0 ug/plate (with and without metabolic activation)
33.0 ug/plate (with and without metabolic activation)
100 ug/plate (with metabolic activation only)
333 ug/plate (with metabolic activation only; complete toxicity seen)
Vehicle / solvent:
Distilled water
Controls
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
9-aminoacridine
sodium azide
other: 4-nitro-o-phenylenediamine; 2-aminoanthracene
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: 20 min at 37 deg C
- Exposure duration: 48 hr at 37 deg C

Cytotoxicity assessed by observation of background lawn.

Plates were examined for the presence of precipitate.

Three plates per dose level were evaluated.
Evaluation criteria:
Revertant colonies counted.
Evaluation criteria were those used by Haworth et al. (1983):
Mutagenic response - a dose-related, reproducible increase in the number of revertants over background (even if the increase is less than two-fold)
Non-mutagenic response - no increase in the number of revertants is elicited
Questionable response - when there is an absence of a clear-cut, dose-related increase in revertants; when the dose-related increases in the number of revertants are not reproducible; when the response is of insufficient magnitude to support a determination of mutagenicity
Statistics:
Not reported (but revertants were reported as: mean +/-SEM).

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not applicable
Positive controls validity:
valid
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

Palladium dichloride was not mutagenic in a good-quality bacterial reverse mutation (Ames) assay when tested up to the limit of toxicity in the presence and absence of metabolic activation.
Executive summary:

In a good quality study, similar to procedure described in OECD Test Guideline 471, palladium dichloride was tested up to the limit of toxicity in a bacterial reverse mutation assay in four strains of Salmonella typhimurium (TA98, TA100, TA1535 and TA1537), in the presence and absence of a S9 mammalian metabolic activation system. [Current guidelines recommend an additional bacterial strain to detect certain oxidising mutagens and cross-linking agents (i.e. TA102 and/or E.coli).]

The maximum doses tested were 33 ug/plate in the absence of S9 and 333 ug/plate in its presence (where complete cytotoxicity was seen; the next-lowest tested dose was 100 ug/plate). There was no convincing evidence of a mutagenic effect, and no dose response in any of the strains tested, either in the presence or absence of S9.

In conclusion, under the conditions of this study, palladium dichloride was not mutagenic to four strains of S. typhimurium, tested up to the limit of toxicity, in the presence and absence of S9.