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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

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

Materials and methods

Principles of method if other than guideline:
Diphenyl cresyl phosphate was investigated in the Salmonella / microsome test for point mutagenic effects in doses up to 12500 µg per plate on four Salmonella typhimurium LT2 mutants. These were the histidine auxotrophic strains TA 1535, TA 100, TA 1537 and TA 98.
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Target gene:
Ames assay: detection of base pair substitutions and frameshift mutations
Species / strain
Species / strain / cell type:
other: S. typhimurium TA 98, 100, 1535, 1537
Metabolic activation:
with and without
Test concentrations with justification for top dose:
12500; 2500; 500; 100; 20 µg DPK per plate
Vehicle / solvent:
Ethanol
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
not specified
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: Sodium azide; Nitrofurantoin; 4-nitro-1,2-phenylenediamine; 2-aminoanthracene
Details on test system and experimental conditions:
Ames test

Results and discussion

Test results
Key result
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:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
valid

Any other information on results incl. tables

Summary of the results with diphenylcresylphosphate in the Salmonella/ microsome test

 S-9 mix  TA 1535  TA 100  TA 1537  TA98
 without  negative    negative    negative    negative
 with    negative    negative    negative    negative

The positive controls ( Sodium azide; Nitrofurantoin; 4-nitro-1,2-phenylenediamine; 2-aminoanthracene) increased the mutant counts to well over double those of the negative controls, and so demonstrated the system´s sensivity and the activity of the S-9 mix.

Applicant's summary and conclusion

Conclusions:
Dipehnyl cresyl phosphate was negative in Salmonella typhimurium strains TA 1535, TA 100, TA 1537 and TA 98 with and without metabolic activation.
Executive summary:

DPK was investigated in the Salmonella/ microsome test for point-mutagenic effects in doses up to 12500 µg per plate on four Salmonella typhimurium strains TA 1535, TA 100, TA 1537 and TA 98.

In all doses, the substance had a strain-specific bacteriotoxic effect, so that the tested range could only be used to a limited extent up to 12500 µg per plate for evaluation purposes. Substance precipitation occured from the dose 2500 µg per plate.

No evidence for mutagenic activity for DPK was found.