1,2-Propanediol, 3-(hexyloxy)-

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:

17 Feb 2011 to 28 Feb 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

adopted in 1997

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

3-(hexyloxy)propane-1,2-diol

EC Number:

600-386-6

Cas Number:

10305-38-1

Molecular formula:

C9H20O3

IUPAC Name:

3-(hexyloxy)propane-1,2-diol

Details on test material:

- Name of test material (as cited in study report): SDX-3096
- Physical state: liquid
- Analytical purity: 99 wt%
- Impurities (identity and concentrations): natural vitamin E at 0.2 wt%
- Lot/batch No.: 00711
- Stability under test conditions: stable under normal condition of use. Avoid high temperature. No reactivity to light and not affected by air
- Storage condition of test material: room temperature in airtight containers

Method

Target gene:

his operon for S. typhimurium strains and trp operon for E.coli strains

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

cofactor supplemented post-mitochondrial fraction (S9 mix), prepared from the livers of rats treated with Phenobarbital (PB) and 5,6-Benzoflavone (BF)

Test concentrations with justification for top dose:

Dose range finding study:
1.22, 4.88, 19.5, 78.1, 313, 1250, 5000 µg/plate with and without metabolic activation - in all strains
Main study:
39.1, 78.1, 156, 313, 625, 1250, 2500 and 5000 µg/plate with and without metabolic activation - S. typhimurium TA1535 and TA1537 strains
156, 313, 625, 1250, 2500 and 5000 µg/plate with and without metabolic activation - S. typhimurium TA98, TA100 and E.coli WP2 uvr A

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: DMSO was used as the vehicle in this study because the test article was soluble at 50 mg/mL and since there was no reaction such as exothermic reaction or generation of gases observed.

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

other: 2-(2-Furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2) and 2-Methoxy-6-chloro-9-[3-(2-chloroethyl)-aminopropylamino]acridine.2HCl (ICR-191)

Remarks:

Without S9 mix: AF-2 in DMSO for TA100 (0.01 µg/plate), WP2uvrA (0.01 µg/plate) + TA98 (0.1 µg/plate). SAZ in water for TA1535 (0.5 µg/plate). ICR-191 in DMSO for TA1537 (1.0 µg/plate)

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

other: 2-Aminoanthracene

Remarks:

With S9 mix: 2-AA in DMSO for TA1535 (2.0 µg/plate) + WP2uvrA (10.0 µg/plate). B[a]P in DMSO for TA100, TA 98 + TA1537 (5.0 µg/plate)

Details on test system and experimental conditions:

METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: 20 min
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: 2 plates per test concentration in the preliminary study and the main study

DETERMINATION OF CYTOTOXICITY
- Method: inspection of the bacterial background lawn

Evaluation criteria:

If a two-fold or more increase in the number of revertant colonies in the test substance groups were observed compared to the negative control group, dose-response and reproducibility were noted, or even if no clear dose-response was observed but there was at least two-fold increase in the number of revertant colonies in comparison with the negative control group and reproducibility was observed in the main test, the test article was judged to be positive.

Statistics:

Statistical analysis was not performed. Individual plate counts and mean values of revertant colonies are presented.

Results and discussion

Test results

Test results 1

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

was evident at 2500 µg/plate and above without metabolic activation and at 5000 µg/plate with metabolic activation in WP2uvrA strain

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

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

Remarks:

was evident at 625 µg/plate and above for TA1535 and TA1537 with metabolic activation, at 1250 µg/plate and above for TA1535 and TA1537 without metabolic activation and at 2500 µg/plate and above for TA100 and TA98 with or without metabolic activation

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

RANGE-FINDING/SCREENING STUDIES: To set the dose levels for the main test, the 50 mg/mL solution was diluted 6 times using a common ratio of 4 and a total of 7 dose levels were selected (1.22, 4.88, 19.5, 78.1, 313, 1250 and 5000 µg/plate) in the dose-finding test. Precipitation on the plate and coloration by the test substance in the test systems were not observed at any dose levels with or without metabolic activation. Growth inhibition was investigated by observing the bacterial background lawn using a stereoscopic microscope. Growth inhibition was observed at 1250 µg/plate and above for TA1535 and 1537 with and without metabolic activation, and at 5000 µg/plate for TA100, TA98 and WP2uvrA with and without metabolic activation. Therefore, for the main test the maximum dose, the minimum dose at which growth inhibition was observed, was set at 1250 µg/plate in TA1535 and TA1537 with and without metabolic activation and set at 5000 µg/plate in TA100, TA98 and WP2uvrA with or without metabolic activation. A total of 6 dose levels were selected by diluting 5 times at a common ratio of 2.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1. Test results of main study

With or without S9-mix	Test substance concentration (µg/plate)	Mean number of revertant colonies per plate (average of 2 plates)
		Base-pair substitution type			Frameshift type
		TA100	TA1535	WP2uvrA	TA98	TA1537
-	0	92	12	18	14	8
-	39.1	NT	13	NT	NT	5
-	78.1	NT	12	NT	NT	7
-	156	93	13	25	16	6
-	313	89	11	21	15	5
-	625	99	6	17	11	4
-	1250	83	8*	24	12	7*
-	2500	46*	NT	9*	12*	NT
-	5000	0*	NT	0*	0*	NT
Positive controls, -S9	Name	AF-2	SAZ	AF-2	AF-2	ICR-191
	Concentration (µg/plate)	0.01	0.5	0.01	0.1	1.0
	Mean No. of colonies/plate (average of 2)	564	235	85	523	1063
+	0	112	9	27	39	11
+	39.1	NT	10	NT	NT	10
+	78.1	NT	6	NT	NT	8
+	156	104	9	24	29	8
+	313	111	9	20	35	8
+	625	112	11*	30	28	11*
+	1250	106	9*	23	24	7*
+	2500	93*	NT	23	25*	NT
+	5000	65*	NT	5*	13*	NT
Positive controls, +S9	Name	B[a]P	2-AA	2-AA	B[a]P	B[a]P
	Concentration (µg/plate)	5.0	2.0	10.0	5.0	5.0
	Mean No. of colonies/plate (average of 2 plates)	910	315	773	353	96

AF-2 =2-(furyl)-3-(5-nitro-2-furyl)acrylamide

SAZ = Sodium azide

ICR-191 = 2-Methoxy-6-chloro-9-[3-(2-chloroethyl)-aminopropylamino]acridine.2HCl

2-AA = 2-Aminoanthracene

B[a]P=Benzo[a]pyrene

* = Growth inhibition of tester strains was observed

NT: Not tested

Table 2. Test results of dose-finding study

With or without S9-mix	Test substance concentration (µg/plate)	Mean number of revertant colonies per plate (average of 2 plates)
		Base-pair substitution type			Frameshift type
		TA100	TA1535	WP2uvrA	TA98	TA1537
-	0	81	10	22	15	7
-	1.22	93	7	25	16	8
-	4.88	84	8	27	15	6
-	19.5	111	7	35	12	8
-	78.1	91	5	33	17	7
-	313	109	9	26	13	8
-	1250	77	7*	21	13	6*
-	5000	0*	0*	0*	0*	0*
Positive controls, -S9	Name	AF-2	SAZ	AF-2	AF-2	ICR-191
	Concentration (µg/plate)	0.01	0.5	0.01	0.1	1.0
	Mean No. of colonies/plate (average of 2 plates)	695	164	90	501	1788
+	0	115	7	32	32	13
+	1.22	108	10	27	36	14
+	4.88	104	10	22	36	13
+	19.5	90	8	25	26	9
+	78.1	116	9	25	26	12
+	313	92	5	28	35	9
+	1250	84	7*	25	31	10*
+	5000	63*	0*	10*	18*	7*
Positive controls, +S9	Name	B[a]P	2-AA	2-AA	B[a]P	B[a]P
	Concentration (µg/plate)	5.0	2.0	10.0	5.0	5.0
	Mean No. of colonies/plate (average of 2 plates)	999	223	926	333	107

AF-2 =2-(furyl)-3-(5-nitro-2-furyl)acrylamide

SAZ = Sodium azide

ICR-191 = 2-Methoxy-6-chloro-9-[3-(2-chloroethyl)-aminopropylamino]acridine.2HCl

2-AA = 2-Aminoanthracene

B[a]P=Benzo[a]pyrene

* = Growth inhibition of tester strains was observed

NT: Not tested

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative