2,6-di-tert-butylphenol

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:

1984-08-13 to 1985-01-07

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study followed standard methodology, but not all details of methodology included in report.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: as described in Ames, B.N. et al, Mutation Research 31: pp. 347-364, 1975

GLP compliance:

yes (incl. QA statement)

Remarks:

GLP Regulations stated in Federal Register, Vol. 43, No. 247, 12/22/1978.

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2,6-di-tert-butylphenol

EC Number:

204-884-0

EC Name:

2,6-di-tert-butylphenol

Cas Number:

128-39-2

Molecular formula:

C14H22O

IUPAC Name:

2,6-di-tert-butylphenol

Details on test material:

- Name of test material (as cited in study report): AN 701
- Physical state: a yellow-brown liquid

Method

Target gene:

Histidine locus in selected strains

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 liver S-9 fraction

Test concentrations with justification for top dose:

2.5 x 10-2, 5 x 10-3, 2.5 x 10-3, 5 x 10-4, 2.5 x 10-4 mg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: acetone
- Justification for choice of solvent/vehicle: solubility of test article was best in this solvent

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

not specified

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)
NUMBER OF REPLICATIONS: three

Evaluation criteria:

Positive response would be an increase in mutant colonies greater than three times the rate seen in the solvent control for that test strain. In the case of TA 98, the solvent control test with activation showed a rate below the spontaneous rate and the historical control. For that test, the spontaneous rate was used for comparison rather than the solvent control results.

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:

other: The highest dose rate (2.5 x 10-2 mg/plate) showed cytotoxicity for TA 1535, TA 1537, and TA 100 with and without metabolic activation.

Vehicle controls validity:

other: Solvent control data acceptable, except for TA 98 with activation. Mutation rate was below spontaneous and historical control for that test. Spontaneous rate used for comparison in that test.

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Mutant colony data for Salmonella typhimurium Ames test for AN 701

Strain	Activation	Solvent Control	Positive Control	2.5 x 10^-2mg/plate	5 x 10^-3mg/plate	2.5 x 10^-3mg/plate	5 x 10^-4mg/plate	2.5 x 10^-4mg/plate
TA1535	- +	6 4	35* 28*	6 4	7 5	4 5	6 8	8 8
TA1537	- +	6 9	116* 718*	6 10	7 10	10 10	9 8	8 7
TA98	- +	9 15**	275* 628	12 9	11 9	21 17	24 19	17 12
TA100	- +	89 98	3175* TNTC*	110 111	110 104	116 111	107 113	95 100

* > 3 times solvent control

** Spontaneous rate

TNTC too numerous to count

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with metabolic activation
negative without metabolic activation

Test article did not induce a dose related increase in mutant colonies in any Salmonella typhimurium strains tested (TA 1535, TA1537, TA98, TA100) with or without metabolic activation. Therefore, AN 701 was not genetically active in the Salmonella/Microsomal Assay.

Executive summary:

Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100 were tested in a plate incorporation Ames test in the presence and absence of metabolic activation (S-9 fraction from livers of rats induced with Arocolor 1254) with test article dissolved in acetone. Dose levels were 2.5 x 10^-2, 5 x 10^-3, 2.5 x 10^-3, 5 x 10^-4, 2.5 x 10^-4 mg AN 701/plate. An 701 was soluble at all dose levels tested. Each dose was treated in triplicate. An untreated control, solvent control, and positive control (appropriate to the strain and activation state) were tested concurrently. The highest concentration of AN 701 demonstrated toxicity in strains TA 1535, TA 1537, and TA 100 with and without metabolic activation. AN 701 did not induce a dose related increase in mutant colonies in any strains with or without activation.