Oligomerisation and alkylation reaction products of 2-phenylpropene and phenol

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27 Jun. - 13 Jul. 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Principles of method if other than guideline:

plate incorporation assay and preincubation test

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

1

Reference substance name:

Oligomerisation and alkylation reaction products of 2-phenylpropene and phenol

EC Number:

700-960-7

Cas Number:

68512-30-1

Molecular formula:

not applicable

IUPAC Name:

Oligomerisation and alkylation reaction products of 2-phenylpropene and phenol

Test material form:

liquid: viscous

Details on test material:

- Manufacturers identification: Novares LA 300
- Substance type: organic
- Test material is 'Oligomerisation and alkylation reaction products of 2-phenylpropene and phenol' (OAPP), EC list number 700-960-7 (assigned manually to validated substances from inquiries by ECHA). Originally the substance phenol, methylstyrenated, CAS No. 68512-30-1, EC No. 270-966-8 was submitted for registration. Subsequent to substance validation, the identity of the substance was changed by ECHA.
- for additional information see respective study record

Specific details on test material used for the study:

- Name of test material (as cited in study report): Novares LA 300 (phenol, methylstyrenated)
- Lot/batch No.: 24087
- Composition of test material: composition is specified in IUCLID Sect. 13 - Assessment reports under Certificate of Analysis_Novares LA 300_phenol, methylstyrenated
- Stability under test conditions: no measured data; based on chemical structure assumed to be stable
- Storage condition of test material: room temperature, exclusion of light

Method

Species / strain

Species / strain 1

Species / strain / cell type:

other: S. typhimurium TA 1535, TA 1537, TA 98 and TA 102

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 100

Metabolic activation:

with and without

Metabolic activation system:

Microsomal fraction prepared from induced livers of male Wistar rats, induced with phenobarbital (80 mg/kg bw) and ß-naphthoflavone (100 mg/kg bw) orally (3x)

Test concentrations with justification for top dose:

1st experiment: 10, 31.6, 100, 316, 1000, 2500, and 5000 µg/plate (all strains, +/-S9)
2nd experiment: 62.5, 125, 250, 500, 1000, and 1500 µg/plate (all strains, -S9)
62.5, 125, 250, 500, 1000, 2000, 3500, and 5000 µg/plate (all strains except TA 100, +S9)
250, 500, 1000, 2000, 4000, and 5000 µg/plate (TA 100, +S9)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: compatible with survival of bacteria and S9 activity

Controls

Untreated negative controls:

yes

Remarks:

dist. water

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

other: without S9: sodium azide (TA100, TA1535); 4-NOPD (Ta98, TA1537); MMS (TA102) // with S9: 2-aminoanthracene (all strains)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (1st and 2nd experiment: plate incorporation)

NUMBER OF REPLICATIONS: 3 per concentration

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth/colony formation

Evaluation criteria:

Considered as mutagenic
- if a clear and dose-related increase in the number of revertants occurs in at least one tester with or without metabolic activation
and/or
- if a biologically relevant positive response for at least one of the dose groups occurs in at least one tester with or without metabolic activation.

An increase is considered relevant
- if in TA 100 and TA 102 mutation rate is at least twice as high as the rate of the solvent control;
- if in TA 98, TA 1535, and TA 1537 the mutation rate is at least 3x higher than that of the solvent control.

Statistics:

According to the OECD guidelines, the biological relevance is the criterion for the interpretation of the results: a statistical evaluation was not considered necessary under this premise (report p. 21).

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

>= 250 µg/pl., depending on strain and presence of S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

>= 250 µg/pl., depending on strain and presence of S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

>= 250 µg/pl., depending on strain and presence of S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

reproducible in both tests

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

>= 250 µg/pl., depending on strain and presence of S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with

Genotoxicity:

ambiguous

Remarks:

reproducible in both tests at >= 2000 µg/pl.

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

reproducible in both tests at >= 1000 µg/pl.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

Summary:

No biologically relevant increases in revertant colony numbers were observed in the four tester strains, TA 1535, TA 1537, TA 98 and TA 102, following treatment with Novares LA 300, either in the presence or in the absence of metabolic activation.

An unremarkable dose-related increase in the mutation rate was found in tester strain TA 100 under metabolic activation: a maximum mutation factor of 2.8 was reached at a dose of 4000 µg/plate. The mutagenic doses were cytotoxic as well.

All reference mutagens induced distinct increases of revertant colonies indicating the validity of the experiment.

Applicant's summary and conclusion

Conclusions:

In one (TA 100) out of five tester strains (other strains TA 1535, TA 1537, TA 98, TA 102), a weak mutagenic dose-related response was observed with metabolic activation. The maximum mutation factor reached was 2.8 at the test substance concentration of 4000 µg/plate. The mutagenic doses were cytotoxic as well.
Overall, the results is considered to be "ambiguous".