2-butyl-2-ethylpropanediol

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:

6 to 27 April 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline and GLP-compliant study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

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

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-butyl-2-ethylpropanediol

EC Number:

204-111-7

EC Name:

2-butyl-2-ethylpropanediol

Cas Number:

115-84-4

Molecular formula:

C9H20O2

IUPAC Name:

2-butyl-2-ethylpropane-1,3-diol

Constituent 2

Reference substance name:

2-Butyl-2-ethyl-1,3-propanediol

IUPAC Name:

2-Butyl-2-ethyl-1,3-propanediol

Test material form:

solid: crystalline

Details on test material:

- Name of test material (as cited in study report): BEPD
- Physical state: colourless solid
- Analytical purity: 99.5%
- Batch number: HRC 28.3.95/9
- Storage conditions: at room temperature
- Stability: assumed stable for 6 months from receipt at HRC on 28 March 1995

Method

Target gene:

Reversion to histidine-independence

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:

Liver post-mitochondrial supernatant (S9 fraction) from male Sprague-Dawley rats induced with Aroclor 1254 prior to sacrifice. Before use, the S9 fraction was supplemented with appropriate co-factors.

Test concentrations with justification for top dose:

0 (ethanol), 50, 150, 500, 1500, 5000 µg/plate (-S9)
0 (ethanol), 50, 150, 500, 1500, 5000 µg/plate (+S9)

Vehicle / solvent:

Ethanol

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

ethanol

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: The positive control compounds used were 2-aminoanthracene (+S9); N-ethyl-N'-nitro-N-nitrosoguanidine, 2-nitrofluorene and 9-aminoacridine (-S9)

Details on test system and experimental conditions:

Triplicate cultures of each bacterial strain were exposed to the test material dissolved in ethanol in the absence and presence of S9-fraction. The plate incorporation method was used for both the initial and confirmatory assays. Plates were incubated for 48 hours. From each triplicate plate, the number of revertant colonies was determined (using a Seescan automatic colony counter); mean revertants were also calculated for each exposure condition. Cytotoxicty was also observed.

Evaluation criteria:

The laboratory's criterion for a positive response in this assay is shown below:
At least a 2-fold increase in the mean number of revertants per plate in at least one tester strain compared to the solvent control in two separate experiments, accompanied by a concentration-response relationship.

Statistics:

Not applicable

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

Additional information on results:

In the preliminary cytotoxicity assessments, BEPD was not toxic towards the tester strains, therefore, 5000 µg/plate was therefore chosen as the top dose level in the mutation tests.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

BEPD toxicity was observed at 5000 µg/plate with TA98 in the absence of S9 -fraction in both mutation tests. No substantial increases in revertant colony numbers were recorded for any of the tester strains following treatment with BEPD at any dose level, in the presence or absence of S9 -fraction, in either mutation test.

Ames test - summary of findings

Mean number of revertant colonies
Initial experiment
Exposure (µg/plate)	+S9				-S9
	TA 1535	TA 1537	TA 98	TA 100	TA 1535	TA 1537	TA 98	TA 100
ethanol	19	15	28	127	14	13	23	122
0	17	14	28	141	14	14	26	124
50	15	10	32	126	17	14	25	123
150	18	13	29	109	14	12	29	112
500	8	11	28	113	10	10	26	109
1500	15	10	21	88	12	11	22	119
5000	11	9	27	117	9	7	-	113
Confirmatory experiment
Exposure (µg/plate)	+S9				-S9
	TA 1535	TA 1537	TA 98	TA 100	TA 1535	TA 1537	TA 98	TA 100
ethanol	13	11	26	118	13	10	25	121
0	15	11	24	118	11	15	21	120
50	13	9	25	118	9	8	22	96
150	11	9	21	125	7	9	20	102
500	10	9	24	105	10	13	23	109
1500	11	12	26	107	9	7	23	109
5000	10	8	19	86	9	12	-	95

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

BEPD was not mutagenic under the conditions of this study.

Executive summary:

The mutagenicity of BEPD was investigated in an Ames test (plate incorporated method) using Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100. Triplicate plates were exposed to the test substance (dissolved in ethanol) at 0, 50, 150, 500, 1500 and 5000 µg/plate in the presence and absence of exogenous metabolic activation system (Aroclor 1254 -induced male Sprague-Dawley rat liver S9 fraction). The assay was repeated using the same concentrations of BEPD. No evidence for mutagenicity was seen in the absence or presence of a metabolic activation system. Results were confirmed in an independently repeated assay. Appropriate positive control compounds confirmed the sensitivity of the assay.