Potassium propionate

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

- published data (Ishidate et al. 1984), S. typhimurium tester strains TA92, TA94, TA98, TA100, TA1535, and TA1537 were exposed to six different concentrations of sodium propionate with the preincubation method, no increase of revertants was detected, not mutagenic

- published data (Ishidate et al. 1984), S. typhimurium tester strains TA92, TA94, TA98, TA100, TA1535, and TA1537 were exposed to six different concentrations of calcium propionate with the preincubation method, no increase of revertants was detected, not mutagenic

- published data (Basler et al. 1987), mutagenicity of Propionic acid was tested in an assay conducted according to Ames et al., 1975. The tester strains TA98, TA100, TA1535 and TA1537 were incubated with 0,0.001, 0.03, 0.1, 0.3, 1.0, 3.3, and 10.0 µl of Propionic acid for 48h, no increase of revertants was detected, not mutagenic

- published data (Basler et al. 1987), the mutagenic potential of propionic acid was determined using a bacterial DNA repair test. E.coli strains WP2, WP67 uvrA-, polA- and CM 871 uvrA-, recA- and lexA- were exposed to three different concentrations of propionic acid for 24 h at 37°C, in the DNA repair test, propionic acid inhibited E. coli strains WP67 uvrA-, polA-and CM87 uvrA-, recA- and lexA- more than the DNA-repair-proficient strain WP2

- published data (Basler et al. 1987), the mutagenic potential of propionic acid was determined in the SOS chromotest. The tester strain E. coli PQ37 was exposed to seven concentrations of propionic acid for 2h at 37°C. After incubation for 2hr
B-galactosidase was measured in one series of tubes and alkaline phosphatase activity in the other. In the SOS chromotest, propionic acid showed no increase of the SOS induction factor in E. coli strain PQ37, not mutagenic

- published data (Zeigler et al. 1992), 311 chemicals were tested for their muagenic potential in a bacterial reverse mutation assay conducted according to Ames et al., 1975. S. typhimurium tester strains were exposed to 0, 100, 333, 1000, 3333, 6667, and 10000 µg/plate with the preincubation method for 48 h, , no increase of revertants was detected, not mutagenic

- published data (Khoudokormoff et al. 1978), DNA repair test; Rec-assay (DNA repair test) using the Bacillus subtilis mutant strain M45 rec-, unable to repair DNA damage and the wild type strain H17 rec+ as control, concentration 10 mg/mL, incubated for 24h at 37°C, not mutagenic

- published data (Ohta et al. 1980), the mutagenicity of 18 chemicals were investigated in a bacterial reverse mutation assay (Ames test) with the S. typhimurium tester strains TA98, TA100, TA1535, TA1537, TA1538 and E. Coli WP2 hcr trp strain. Calcium propionate did not show an increase of the number of revertants in this assay, not mutagenic

- QSAR Estimation with DERAK Nexus model, non-mutagenic

-QSAR estimation with SARAH Nexus model, non-mutagenic

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro DNA damage and/or repair study

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

other: Rec-assay (DNA repair test) using the Bacillus subtilis mutant strain M45 rec-, unable to repair DNA damage and the wild type strain H17 rec+ as control

Version / remarks:

Rec-assay (DNA repair test) using the Bacillus subtilis mutant strain M45
rec-, unable to repair DNA damage and the wild type strain H17 rec+ as control

GLP compliance:

no

Type of assay:

Bacillus subtilis recombination assay

Species / strain / cell type:

bacteria, other: Bacillus subtilis strain M45 rec-, wild type strain H17 rec+

Test concentrations with justification for top dose:

10 mg/mL as stated in the material and methods section of the publication.

Key result

Species / strain:

bacteria, other: Bacillus subtilis strain M45 rec-, wild type strain H17 rec+

Metabolic activation:

not specified

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

True negative controls validity:

not specified

Positive controls validity:

valid

Ca-propionate (1%) showed no mutagenic activity under any of the conditions tested.

Conclusions:

Calcium propionate is not mutagenic in the DNA repair test with Bacillus subtilis under the conditions of the test.

Executive summary:

In a Bacillus subtilis recombination test in bacteria Bacillus subtilis strain M45  rec-, wild type strain H17 rec+  was exposed to Calcium Propionate at 10 mg/mL for overnight at 6°C and subsequently for 24h at 37°C. Afterwards the growth inhibition was determined. In the recombination test, Calcium Propionate does not inhibit bacterial growth under the conditions of the test.

This study is classified as not acceptable for assessment based on methodological and documentation limits. This study does not satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) but the data is part of an overall Weight of Evidence assessment.

Reference 2

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

5 strains of Salmonella typhimurium, TA1535, TA100, TA1537, TA1538 and TA98 were used

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

his locus

Species / strain / cell type:

S. typhimurium, other: TA1535, TA100, TA1537, TA1538 and TA98

Remarks:

and Escherichia coli WP2 hcr trp

Metabolic activation:

with and without

Metabolic activation system:

Type and composition of metabolic activation system:
- source of S9: male rats
- method of preparation of S9 mix : male rats treated i.p., at 500 mg/ kg, with a polychlorinated biphenyl mixture (Aroclor 1254) according to Ames et al.
- concentration or volume of S9 mix and S9 in the final culture medium : S9 mix contained 0.3 mL S9 fraction, 8 µmol MgCl2, 33 µmol KCI, 5 µmol glucose 6-phosphate, 4 µmol NADP and 100 µmol sodium phosphate buffer (pH 7.4) per mL. To 2 mL of molten top agar, which contained 50 µM L-histidine-biotin for the S. typhimurium strains or 50 µM L-trytophan for the E. coli strain and was kept at 45°C, were added 0.1 mL of bacterial suspension in 1/15 M phosphate buffer (pH 7), 0.1 mL of a solution of a compound and 0.5 mL of S9 mix. The mixture was poured onto a minimal glucose agar plate with modified Vogel--Bonner E medium. Revertants were scored after 2 days incubation at 37°C.

Test concentrations with justification for top dose:

Not reported

Vehicle / solvent:

Not reported

Evaluation criteria:

not specified

Key result

Species / strain:

E. coli WP2

Remarks:

WP2 hcr trp

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

True negative controls validity:

not specified

Positive controls validity:

not specified

Key result

Species / strain:

S. typhimurium, other: TA1535, TA100, TA1537, TA1538 and TA98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

True negative controls validity:

not specified

Positive controls validity:

not specified

Conclusions:

In the present publication of Ohta et al., 1980, the mutagenicity of 18 chemicals were investigated in a bacterial reverse mutation assay (Ames test) with the S. typhimurium tester strains TA98, TA100, TA1535, TA1537, TA1538 and E. Coli WP2 hcr trp strain. Calcium propionate did not show an increase of the number of revertants in this assay and is thus not conidered a mutagen under the conditions of the test.

Executive summary:

In a reverse gene mutation assay in bacteria OECD TG 471, strains TA98, TA100, TA1535, TA1537 and TA 1538 of S. typhimurium as well as E. Coli WP2 hcr trp were exposed to Calcium Propionate at several concentrations with the preincubation method in the presence and absence of mammalian metabolic activation for 48 h.

This study is classified as not acceptable for assessment based on the documentation limits. This study does not satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) data but is part of an overall Weight of Evidence assessment.

Reference 3

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

Variations in the preincubation protocol among the tested chemicals reflect the evolution of the protocol originally described by Haworth et al. [1983].Please refer to any additional information on materials and methods.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Target gene:

his locus

Species / strain / cell type:

S. typhimurium, other: TA97, TA98, TA100, and TA1535, with some additional use of strain TA1537

Metabolic activation:

with and without

Metabolic activation system:

Type and composition of metabolic activation system:
- source of S9
- method of preparation of S9 mix
- concentration or volume of S9 mix and S9 in the final culture medium
- quality controls of S9 (e.g., enzymatic activity, sterility, metabolic capability)

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

sodium azide

methylmethanesulfonate

mitomycin C

other: 2-aminoanthracene (with metabolic acivation), 4-nitro-o-phenylenediamine (TA97/TA1537, without metabolic activation)

Details on test system and experimental conditions:

NUMBER OF REPLICATIONS:
- Number of cultures per concentration triplicate
- Number of independent experiments at least two

METHOD OF TREATMENT/ EXPOSURE:
- Cell density at seeding (if applicable): Not reported
- Test substance added in medium; preincubation

METHODS FOR MEASUREMENT OF CYTOTOXICITY
- Method, e.g.: Toxic concentrations were defined as those that produced a decrease in the number of his+ colonies, or a clearing in the density of the
background lawn, or both.

Evaluation criteria:

Please refer to the Any other infomation on materials and methods section

Key result

Species / strain:

S. typhimurium, other: TA97, TA98, TA100, TA1535, TA1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

slight clearing of backgroud lawn at 10000 µg/plate with metabolic acitvation

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

valid

Results:

 

Dose	TA100										TA1535
	NA (-)		10% HLI (-)		30% HLI (-)		10% RLI (-)		30% RLI (-)		NA (-)		10% HLI (-)		30% HLI (-)		10% RLI (-)		30% RLI (-)
µg/plate	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM
0.0	83	2.0	90	6.1	120	11.7	100	10.5	126	4.5	22	4.8	12	2.8	11	1.8	12	1.5	13	2.2
100.0	82	1.2	84	5.5	105	3.5	95	3.0	108	5.3	16	2.5	13	1.5	10	0.9	9	1.5	14	2.1
333.0	84	3.2	92	5.0	120	6.7	97	6.2	138	8.1	14	0.7	12	2.0	10	1.5	15	0.9	14	1.5
1000.0	88	2.3	92	2.3	111	7.6	81	7.5	112	7.5	15	2.7	10	2.0	9	2.2	9	1.5	12	0.6
3333.0	85	8.2	102	4.7	108	5.5	92	1.2	130	9.0	18	0.7	8p	0.7	12	1.5	8p	2.9	14	3.8
6667.0	70	1.2									12	0.9
10000.0			99s	11.6	52s	21.1	t		84s	0.3			7s	2.2	8s	1.3	4s	2.3	7s	2.9
POS	382	13.9	402	10.3	529	14.5	303	11.3	769	30.6	272	4.7	101	5.7	94	3.8	117	6.6	79	7.4

Dose	TA1537
	NA (-)		30% HLI (-)		30% RLI (-)
µg/plate	Mean	SEM	Mean	SEM	Mean	SEM
0.0	7	0.7	7	0.7	6	0.6
100.0	6	0.3	8	0.7	9	0.7
333.0	6	0.9	9	1.0	11	1.3
1000.0	6	0.9	9	2.2	8	1.5
3333.0	5	0.9	8	0.3	10	0.9
6667.0	4	0.6
10000.0			5s	0.3	9s	2.6
POS	53	4.6	117	7.2	54	3.4

Dose	TA97										TA98
	NA (-)		10% HLI (-)		30% HLI (-)		10% RLI (-)		30% RLI (-)		NA (-)		10% HLI (-)		30% HLI (-)		10% RLI (-)		30% RLI (-)
µg/plate	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM	Mean	SEM
0.0	88	8.5	110	5.5	130	6.2	117	6.4	175	2.0	16	2.3	25	2.3	27	3.5	25	1.5	33	0.9
100.0	89	10.2	109	7.9	135	6.8	121	1.8	168	3.6	19	0.3	22	3.8	30	3.5	26	1.5	21	2.0
333.0	80	3.8	97	2.5	125	7.0	111	2.7	154	13.6	12	1.7	23	2.0	27	0.9	23	4.0	23	5.5
1000.0	73	2.0	108	4.5	115	6.7	110	8.8	176	4.5	13	1.2	34	1.8	21	4.1	21	1.8	27	4.4
3333.0	44	6.2	102	3.0	114	11.1	98	3.0	193	9.9	17	0.3	21	1.9	21	1.9	22	1.3	28	1.5
6667.0	10s	5.1									15	0.6
10000.0			13s	3.0	45s	2.8	t		95s	5.7			7s	0.7	12s	2.2	10s	4.5	9s	1.8
POS	261	3.0	511	13.5	778	7.9	635	12.1	389	16.6	220	4.2	211	15.5	105	3.2	173	11.0	297	2.0

NA, not activated; HLI, Aroclor 1254-induced hamster liver S-9; RLI, Aroclor 1254-induced rat liver S-9; s, slight clearing of background lawn; t, complete clearing of background lawn (colonies not counted); p, precipitate present in plates; x, precipitate present with toxicity; +, mutagenic; +W, weakly mutagenic; ?, questionable response; - , nonmutagenic.

 

 

 

Conclusions:

In the publication of Zeiger et al., 1992, 311 chemicals were tested for their mutagenic potential in a bacterial reverse mutation assay conducted according to Ames et al., 1975. S. typhimurium tester strains were exposed to 0, 100, 333, 1000, 3333, 6667, and 10000 µg/plate with the preincubation method for 48 h. There was no increase of the number of revertants in any tester strain at concentrations up to occurring toxicity, thus propionic acid is not considered mutagenic under the conditions of the test.

Executive summary:

In a reverse gene mutation assay in bacteria OECD TG 471, strains TA97, TA98, TA100, TA1535, TA1537 of S. typhimurium were exposed to Propionic acid at concentrations of 0, 100, 333, 1000, 3333, 6667, and 10000 µg/plate with the preincubation method in the presence and absence of mammalian metabolic activation for 48 h.

Propionic acid was tested up to cytotoxic concentrations, as indicated by the slight reduction of background lawn seen in the highest concentration in all tester strains. The positive controls induced  the appropriate responses in the corresponding strains. There was no evidence of induced mutant colonies over background.

This study is classified as acceptable. This study satisfies the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) data.

Reference 4

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

Test was performed with four instead of five tester strains

Deviations:

yes

Remarks:

Test was performed with four instead of five tester strains

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

his locus

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Type and composition of metabolic activation system:
- source of S9: Wistar rats
- method of preparation of S9 mix: according to Ames et al. (1975)
- concentration or volume of S9 mix and S9 in the final culture medium : 1 mL
S-9 mix contained 8 µmol MgCl2, 33 µmol KCI, 5 µmol glucose-6-phosphate, 4 µmol NADP and 100 µmol sodium phosphate, pH 7.4, together with 1.2 mg S-9 fraction.

Test concentrations with justification for top dose:

0, 0.01, 0.03, 0.1, 0.3, 1.0, 3.3, and 10.0 µL/Plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water

Untreated negative controls:

yes

Remarks:

water

Negative solvent / vehicle controls:

yes

Remarks:

water

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

other: 2-Aminoanthracene, 10 µg, without metabolic acitvation

Details on test system and experimental conditions:

NUMBER OF REPLICATIONS:
- Number of cultures per concentration: triplicate
- Number of independent experiments: two

METHOD OF TREATMENT/ EXPOSURE:
- Cell density at seeding (if applicable): Late log-phase cultures
- Test substance added in medium; in agar (plate incorporation)

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

	Revertants per plate
	- S9 Mix				+ S 9 Mix
	TA98	TA100	TA1535	TA1537	TA98	TA100	TA1535	TA1537
H2O	40/28	109/151	20/12	9/9	47/48	143/171	14/29	7/9
Propionic acid
0.01	52/27	123/146	17/18	7/10	44/56	123/160	12/27	10/12
0.03	49/31	111/140	17/16	12/14	45/75	111/166	12/31	7/9
0.1	48/27	124/132	22/14	10/13	49/55	132/170	12/32	6/10
0.3	46/27	110/133	15/13	10/11	37/62	156/174	16/32	6/10
1.0	53/26	121/137	18/19	8/10	39/65	139/166	9/30	11/7
3.3	57/27	104/140	19/15	10/7	43/60	140/157	7/19	8/7
10.0	37/24	103/116	16/10	6/6	23/38	137/147	8/21	6/6
AA (1µg)					643/530	940/872	84/64	37/43
2-NF (1 µg)	520/471
NaN3 (1 µg)		801/760	760/598
AAc (10µg)				56/63

Conclusions:

In the present test the mutagenicity of Propionic acid was tested in an assay conducted according to Ames et al., 1975. The tester strains TA98, TA100, TA1535 and TA1537 were incubated with 0,0.001, 0.03, 0.1, 0.3, 1.0, 3.3, and 10.0 µl of Propionic acid for 48h and the number revertants were counted. There was no significant increase of the number of revertants in each tester strain with or without metabolic acitvation, thus, the substance is not considered to be mutagenic under the conditions of the test.

Executive summary:

In a reverse gene mutation assay in bacteria according to OECD TG 471, strains TA98, TA100, TA1535, TA1537 of S. typhimurium were exposed to Propionic acid at six concentrations of 0, 0.01, 0.03, 0.1, 0.3, 1.0, 3.3, and 10.0 µL/Plate in the presence and absence of mammalian metabolic activation for 48 h.

This study is classified as acceptable for assessment but shows documentation limits. This study does satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) and the data is part of an overall Weight of Evidence assessment.

Reference 5

Endpoint:

in vitro DNA damage and/or repair study

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.16 (Mitotic Recombination - Saccharomyces cerevisiae)

Version / remarks:

SOS chromotest was performed in Escherichia Coli

GLP compliance:

no

Type of assay:

Bacillus subtilis recombination assay

Target gene:

sfiA-lacZ fusion gene

Species / strain / cell type:

E. coli, other: PQ37

Metabolic activation:

with and without

Metabolic activation system:

S9 mix
Each 10 mL S-9 mix contained: 0.2 mL salt solution (1.65 M-KCI + 0.4 M-MgCl;-6H2O), 0.05 mL glucose-6-phosphate (1 M), 0.15 mL NADP (0.1 M), 2.5 mL tris(hydroxymethyl)amino-methane buffer (0.41 M pH 7.4), 6.1 mL Lamp medium and 1 mL S-9 fraction. The S-9 fraction was prepared from Aroclor 1254-treated Wistar rats according to Ames, McCann & Yamasaki (I975) and had a protein content of 30mg/mL (Lowry et al. 1951).

Test concentrations with justification for top dose:

seven concentrations, from 0.01 to10.0 mM
0, 0.01, 0.03, 0.1, 0.3, 1.0, 3.3, 10.0 mM

Vehicle / solvent:

double distilled water

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

double distilled water

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

benzo(a)pyrene

Details on test system and experimental conditions:

The SOS chromotest was performed according to the revised method of Quillardet et al. (1985), using E. coli PQ37 (from M. Hofnung, Paris, France).
From an overnight culture 0.4 mL bacteria was diluted with 20 mL Lamp medium and incubated at 37°C in an incubator with shaking until there were up to 1x E+08 bacteria/mL. From that culture 1 mLwas diluted in either 9 mL fresh Lamp medium, or 9 mL S-9 mix for assay with metabolic activation. The test was carried out in two series of glass tubes containing 0.25 mL diluted bacterial suspension and the dissolved test compound (seven concentrations, from 0.01 to 10.0 mM). After incubation for 2hr β-galactosidase was measured in one series of tubes and alkaline phosphatase activity in the other.
All experiments were performed twice and all measurements were made in duplicate. Positive control chemicals were included in each set of assays;
4-NQO was used in experiments without metabolic activation, and B[a]P in experiments with metabolic activation.

Evaluation criteria:

The results are expressed as SOS induction factors, which represent the ratios of β-galactosidase to alkaline phosphatase units. The ratio for the solvent control (water) was set at 1.0. A substance was considered to be genotoxic in this test system if there was an increase of 0.5 or more in the SOS-induction factor.

Key result

Species / strain:

E. coli, other: PQ37

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

True negative controls validity:

not specified

Positive controls validity:

valid

 

Conc. of the test chemical (mM)	SOS induction factor *
	-S-9 #		+S-9 #
	Exp. I	Exp.II	Exp. I	Exp.II
H2O	1.0	1.0	1.0	1.0
Propionic acid
0.01	0.8	1.0	1.1	0.9
0.03	0.8	1.2	1.1	0.8
0.1	0.9	1.0	1.1	0.8
0.3	0.9	1.0	1.1	0.7
1.0	0.7	0.9	1.0	0.8
3.3	0.9	1.1	1.1	0.8
10.0	1.1	1.3	1.0	0.7
4-NQO (4µg/mL)	6.9	7.6
B[a]P (1 xE-04 M)			3.6	4.7

4-NQO = 4-Nitroquinoline-N-oxide B[a]P = Benzo[a]pyrene

* Ratio of β-galactosidase to alkaline phosphatase units.

# Each 10 mL S-9 mix contained: 0.2 mL salt solution (1.65 M-KCI + 0.4 M-MgCl;-6H₂O), 0.05 mL glucose-6-phosphate (1 M), 0.15mL NADP (0.1 M), 2.5 mL tris(hydroxymethyl)amino-methane buffer (0.41 M pH 7.4), 6.1 mL Lamp medium and 1 mL S-9 fraction. The S-9 fraction was prepared from Aroclor 1254-treated Wistar rats according to Ames, McCann & Yamasaki (I975) and had a protein content of 30mg/mL (Lowry et al. 1951).

 

 

 

Conclusions:

In the present publication the mutagenic potential of propionic acid was determined in the SOS chromotest. The tester strain E. coli PQ37 was exposed to seven concentrations of propionic acid for 2h at 37°C. After incubation for 2hr
B-galactosidase was measured in one series of tubes and alkaline phosphatase activity in the other. In the SOS chromotest, propionic acid showed no increase of the SOS induction factor in E. coli strain PQ37. Thus, the substance is not considered mutagenic.

Executive summary:

In a SOS chromotest in bacteria E.coli PQ37 was exposed to Propionic acid at seven concentrations for 2h at 37°C. After incubation for 2hrB-galactosidase was measured in one series of tubes and alkaline phosphatase activity in the other. In the SOS chromotest, propionic acid showed no increase of the SOS induction factor in E. coli  strain PQ37.

This study is classified as not acceptable for assessment based on methodological and documentation limits. This study does not satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) but the data is part of an overall Weight of Evidence assessment.

Reference 6

Endpoint:

in vitro DNA damage and/or repair study

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPPTS 870.5500 - Bacterial DNA Damage or Repair Tests

Version / remarks:

E. coli WP2, WP67 uvrA-, polA- and CM 871 uvrA-, recA- and lexA- were used, metabolic acitvation was not further reported

Principles of method if other than guideline:

- Principle of test: Disc diffusion assay
- Short description of test conditions: The tester strains were streaked crosswise onto L-medium agar plates (Luria & Burrous, 1957), and the test compound (three different doses) was spotted on a sterile filter disc (10 mm) in the centre of the cross. The areas of bacterial death were measured after a 24-hr incubation at 37°C.
- Parameters analysed / observed: growth inhibition

GLP compliance:

no

Type of assay:

Bacillus subtilis recombination assay

Species / strain / cell type:

E. coli, other: WP2, WP67 uvrA-, polA- and CM 871 uvrA-, recA- and lexA-

Metabolic activation:

not specified

Test concentrations with justification for top dose:

1, 5, 25 µL propionicacid, concentration not further specified

Vehicle / solvent:

double distilled water

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

ethylmethanesulphonate

methylmethanesulfonate

Key result

Species / strain:

E. coli, other: WP2, WP67 uvrA-, polA- and CM 871 uvrA-, recA- and lexA-

Metabolic activation:

not specified

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

 

		Difference in growth inhibition [mm]*
Substance	Dose [µL]	pol+/polA-	rec+/rec-
H2O	25	0	0
Propionic acid	1	3	3.5
	5	12	8.5
	25	8	6
Positive controls
MMS	2.5	15	39
	5.0	17	44
EMS	5.0	5	23

MMS = Methyl methanesulphonate

EMS = Ethyl methanesulphonate

*Mean values of four plates: pol+= E. coli WP2; polA-=E. coli WP67; rec+= E. coli WP2; rec-= E. coli CM871. Results are expressed as the difference in lethality between repair-deficient and repair-competent strains of E. coli.

 

 

 

Conclusions:

In the present publication the mutagenic potential of propionic acid was determined using a bacterial DNA repair test. E.coli strains WP2, WP67 uvrA-, polA- and CM 871 uvrA-, recA- and lexA- were exposed to three different concentrations of propionic acid for 24 h at 37°C. Afterwards the growth inhibition was determined. In the DNA repair test, propionic acid inhibited E. coli strains WP67 uvrA-, polA-and CM87 uvrA-, recA- and lexA- more than the DNA-repair-proficient strain WP2.

Executive summary:

In a bacterial DNA repair test in bacteria E.coli WP2, WP67 uvrA-, polA- and CM 871 uvrA-, recA- and lexA- were exposed to Propionic acid at three concentrations for 24h at 37°C. Afterwards the growth inhibition was determined. In the DNA repair test, propionic acid inhibited E. coli strains WP67 uvrA-, polA-and CM87 uvrA-, recA- and lexA- more than the DNA-repair-proficient strain WP2.

This study is classified as not acceptable for assessment based on methodological and documentation limits. This study does not satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) but the data is part of an overall Weight of Evidence assessment.

Reference 7

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

test was conducted in the tester strains TA92, TA94, TA98, TA100, TA1535, and TA1537

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

his locus

Species / strain / cell type:

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

Remarks:

additional TA92 and TA94

Metabolic activation:

with and without

Metabolic activation system:

S9-liver-Mix
Type and composition of metabolic activation system:
- source of S9: Fischer rats
- concentration or volume of S9 mix and S9 in the final culture medium: The reaction mixture (S-9 mix) contained 5 mM-glucose 6-phosphate, 4mM-NADPH, 4mM-NADH, 33mM-KCl, 8 mM-MgCI2, 100 mM-phosphate buffer (pH 7.4) and 3.75 ml S-9 (129 mg protein) in a total volume of 12.5 ml.

Test concentrations with justification for top dose:

six concentrations

Vehicle / solvent:

Water

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

not specified

Details on test system and experimental conditions:

NUMBER OF REPLICATIONS:
- Number of cultures per concentration: duplicate
- Number of independent experiments: Not specified

Rationale for test conditions:

As described in Ames et al., 1975

Evaluation criteria:

The result was considered positive if the number of colonies found was twice the number in the control (exposed to the appropriate solvent or untreated).

Key result

Species / strain:

S. typhimurium, other: TA92, TA94, TA98, TA100, TA1535, TA1537

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

highest dose applied 5.0 mg/plate

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

not specified

Conclusions:

In the publication of Ishidate et al., 1984, S. typhimurium tester strains TA92, TA94, TA98, TA100, TA1535, and TA1537 were exposed to six different concentrations of sodium propionate with the preincubation method. Cells were incubated with the test sample and with and without the S9 Mix for 20 min and then plated in duplicates. After 48 h at 37°C the number of revertants were counted. If the number of revertants double during the incubation period the test result is regarded positiv. There was no increase in the number of revertants at each concentration, thus, sodium propionate is not considered mutagenic under the conditions of the test.

Executive summary:

In a reverse gene mutation assay in bacteria according to OECD TG 471, strains TA92, TA94,TA98, TA100, TA1535, TA1537 of S. typhimurium were exposed to Sodium Propionate at six concentrations up to 5.0 mg/plate with the preincubation method in the presence and absence of mammalian metabolic activation for 48 h.

This study is classified as not acceptable for assessment based on the documentation limits. This study does not satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) data but is part of an overall Weight of Evidence assessment.

Reference 8

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

test was conducted in the tester strains TA92, TA94, TA98, TA100, TA1535, and TA1537

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Target gene:

his locus

Species / strain / cell type:

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

Remarks:

additional TA92 and TA94

Metabolic activation:

with and without

Metabolic activation system:

S9-liver-Mix
Type and composition of metabolic activation system:
- source of S9: Fischer rats
- concentration or volume of S9 mix and S9 in the final culture medium: The reaction mixture (S-9 mix) contained 5 mM-glucose 6-phosphate, 4mM-NADPH, 4mM-NADH, 33mM-KCl, 8 mM-MgCI2, 100 mM-phosphate buffer (pH 7.4) and 3.75 ml S-9 (129 mg protein) in a total volume of 12.5 ml.

Test concentrations with justification for top dose:

six concentrations

Vehicle / solvent:

0.1N NaOH

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

not specified

Details on test system and experimental conditions:

NUMBER OF REPLICATIONS:
- Number of cultures per concentration: duplicate
- Number of independent experiments: Not specified

Rationale for test conditions:

As described in Ames et al., 1975

Evaluation criteria:

The result was considered positive if the number of colonies found was twice the number in the control (exposed to the appropriate solvent or untreated).

Key result

Species / strain:

S. typhimurium, other: Ta92, TA94, TA98, TA100, TA1535, TA1537

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

highest dose applied 10.0 mg/plate

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

not specified

Untreated negative controls validity:

not examined

True negative controls validity:

not examined

Positive controls validity:

not specified

Conclusions:

In the publication of Ishidate et al., 1984, S. typhimurium tester strains TA92, TA94, TA98, TA100, TA1535, and TA1537 were exposed to six different concentrations of calcium propionate with the preincubation method. Cells were incubated with the test sample and with and without the S9 Mix for 20 min and then plated in duplicates. After 48 h at 37°C the number of revertants were counted. If the number of revertants double during the incubation period the test result is regarded positiv. There was no increase in the number of revertants at each concentration, thus, calcium propionate is not considered mutagenic under the conditions of the test.

Executive summary:

In a reverse gene mutation assay in bacteria according to OECD TG 471, strains TA92, TA94,TA98, TA100, TA1535, TA1537 of S. typhimurium were exposed to Calcium Propionate at six concentrations up to 5.0 mg/plate with the preincubation method in the presence and absence of mammalian metabolic activation for 48 h.

This study is classified as not acceptable for assessment based on the documentation limits. This study does not satisfy the requirement for Test Guideline OECD 471 for in vitro mutagenicity (bacterial reverse gene mutation) data but is part of an overall Weight of Evidence assessment.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

A Weight of Evidence assessment was conducted to conclude on the potential of potassium propionate (CAS 327-62-8) to induce bacterial reverse mutation with and without metabolic activation. under the conditions of an OECD TG 471 assay. No test data are available with the target substance. Four bacterial reverse mutation assays are publicly available with the structurally close analogues propionic acid and calcium propionate. In addition, in silico predictions were conducted with the QSAR Toolbox as well as with the Lhasa models Derek Nexus and Sarah Nexus. Each of these Lines of Evidence was assessed separately. Qualitative scoring (low, moderate, high) was assigned for both reliability and relevance of each Line of Evidence. The final weight was obtained by combining the scores for reliability and relevance. All Lines of Evidence were assigned moderate to high weight. The results consistently indicate absence of the mutagenic potential of the target.

The Weight of Evidence assessment provides robust basis to conclude that potassium propionate is not mutagenic with and without metabolic activation under the conditions of a Bacterial Reverse Mutation assay in accordance with OECD 471.

Justification for classification or non-classification

Based on the presented data gathered from structural similar substances and the additionally conducted prediction with the QSAR Toolbox as well as with the DEREK and Sarah Nexus model, potassium propionate is not considered mutagenic under the conditions of a bacterial reverse mutation assay (OECD test guideline 471) and thus does not need to be classified according to Regulation (EU) No. 1272/2008 (CLP) and the Globally Harmonized System for Classification and Labelling of Chemicals (GHS).