N-phenylmaleimide

Genetic toxicity: in vitro

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:

1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Test method is based on Japanese Labor Safety & Hygiene Law and Judgement method is based on the draft on the guidance of toxicity studies of drugs animal experiment guidance concerning with Safety of drugs by Walfare Ministry Scientific Finance in 1981.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals

Deviations:

yes

Remarks:

species/strain: S.typhimurium (TA 1535, TA1537, TA98 and TA 100)

Principles of method if other than guideline:

Method: other: In accordance with the Labour Safety & Hygien Law Excusion Criterion.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

N-phenylmaleimide

EC Number:

213-382-0

EC Name:

N-phenylmaleimide

Cas Number:

941-69-5

Molecular formula:

C10H7NO2

IUPAC Name:

1-phenyl-2,5-dihydro-1H-pyrrole-2,5-dione

Details on test material:

purity: 99.5%

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other:

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

S-9 was purchased from Oriental Yeast Co.,Ltd.

Test concentrations with justification for top dose:

10 micro gram /plate: where antibacterial activity were shown

Vehicle / solvent:

DMSO

Controls

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

Migrated to IUCLID6: N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG), 2-nitrofluorene (2-NF), 9-aminoacridine hydrochloride (ACR), 2-aminoanthracene (2-AA)

Details on test system and experimental conditions:

IUCLID4 Type: Ames test

Evaluation criteria:

Labor Safety & Hygiene Law Excusion Criterion

Statistics:

Guideline of toxicity studies of drugs by Welfare Ministry Scientific Finance in 1981

Results and discussion

Test results

Test results 1

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:

other: 10 micro gram/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: 10 micro gram/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH:
- Effects of osmolality:
- Evaporation from medium:
- Water solubility: insoluble
- Precipitation:
- Other confounding effects:


RANGE-FINDING/SCREENING STUDIES: Since antibacterial activity was observed at 5,000 ug/disc, the maximum concentration in execution ceiterion, maximum concentration for the present test was set at 10 ug/Plate at which the test material was slightly antibacterial.


COMPARISON WITH HISTORICAL CONTROL DATA:


ADDITIONAL INFORMATION ON CYTOTOXICITY:

Remarks on result:

other: other:

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Results of the bacterial reversion test (+S9)

concentration: 0.01, 0.05, 0.1, 0.5, 1,5, 10 ug/plate

Species DMSO Substance Positive control

----------------------------------------------------------

TA100： 181 -151 134 492

TA1535: 16 -19 17 198

WP2uvrA: 19 -28 20 209

TA98: 21 -26 25 387

TA1537: 8 -11 9 228

TA1538: 21 -28 24 239

----------------------------------------------------------

Results of the bacterial reversion test (-S9)

concentration: 0.01, 0.05, 0.1, 0.5, 1,5, 10 ug/plate

Species DMSO Substance Positive control

----------------------------------------------------------

TA100 103 -121 111 438

TA1535 17 -24 17 253

WP2uvrA 17 -22 19 228

TA98 15 -21 17 263

TA1537 6 -10 8 229

TA1538 14 -24 20 225

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Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

This substance was judged to be not mutagenic on the basis of the creteria in the guideline of toxicity studies of drugs (drft)

Executive summary:

In a reverse gene mutation assay in bacteria, strains TA100, TA1535, TA98, TA1537, TA1538 of S. typhimurium and E.coli WP2uvrA were exposed to PMI (provided by NIPPON SHOKUBAI on 1984.02.22) include DMSO at concentrations of 0, 0.01, 0.05, 0.1, 0.5, 1, 5, 10 μg/plate in the presence and absence of mammalian metabolic activation. 

  Since PMI showed antibacterial action at the concentration level of 5,000 ug/plate, the maximum concentration in the present test was set at 10 ug/plate at which this substance was slightly antibacterial.

The positive controls induced the appropriate responses in the corresponding strains.  There was no evidence of induced mutant colonies over background.

Genetic toxicity data (Amest and Chromosome aberration) show negative with the test sample provided by NIPPON SHOKUBAI.

Genetic toxicity data (Amest and Chromosome aberration) show positive with the test sample provided by Daihachi Chemical.

The submitter considered that this diffence on result may cause due to the difference smallamount of impurity between two samples

Based on REACH Guidance R.7a Table R.7.7-1, appropriate in vivo mutagenicity studies shall be considered in case of another submitter whose purity is different from above 2 samples..

However, the positive result is considered as equivocal due to these positive findings generated only at highly toxic/cytotoxic concentrations. (REACH Guidance R.7a R.7.4.1)

So, Based on the weight of evidence, the mutagenicity of this substance is considered as negative in vitro.

 

This study is classified as acceptable.  This study is equivalent to the requirement for JAPAN: Guidelines for Screening Mutagenicity Testing (bacterial reverse gene mutation) of Chemicals.