Dodecairon strontium nonadecaoxide

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Data generated according to generally valid testing guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

Minor deviations not impacting validity of the study.

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Dodecairon strontium nonadecaoxide

EC Number:

234-685-4

EC Name:

Dodecairon strontium nonadecaoxide

Cas Number:

12023-91-5

Molecular formula:

Fe12O19.Sr

IUPAC Name:

dodecairon(3+) strontium(2+) nonadecaoxidandiide

Details on test material:

- Name of test material (as cited in study report): Strontiumhexaferrite ("Manipermpulver")
- Analytical purity: 100 % industrial strontiumferrite
- Impurities (identity and concentrations): see section 1.2 of the IUCLid5.2-file
- Composition of test material, percentage of components: see section 1.2 of the IUCLid5.2-file
- Lot/batch No.: S16/179/08
- Expiration date of the lot/batch: 12/2999
- Stability under test conditions: stable
- Storage condition of test material: air-conditioned romm temperature, non-sterile

Method

Target gene:

Genes for sythesis of amino acids. Not specified in detail.

Species / strain

Species / strain 1

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not specified

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

Co-factor supplemented post-mitochondrial fraction (S9) from the liver of Aroclor 1254 induced Sprague-Dawley rats.

Test concentrations with justification for top dose:

Test suspensions:
- 5.00 mg/plate
- 1.52 mg/plate
- 0.46 mg/plate
- 0.14 mg/plate
- 0.04 mg/plate

Vehicle / solvent:

Suspension in water

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

Sterile distilled water

Negative solvent / vehicle controls:

yes

Remarks:

Sterile distilled water = negative control can be regarded as vehicle control, too.

True negative controls:

yes

Remarks:

Sterile distilled water

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

Positive control substance when using S. typhimurium TA 1535, TA 100.

Controls 2

Untreated negative controls:

yes

Remarks:

Sterile distilled water

Negative solvent / vehicle controls:

yes

Remarks:

Sterile distilled water = negative control can be regarded as vehicle control, too.

True negative controls:

yes

Remarks:

Sterile distilled water

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Remarks:

Positive control substance when using each of the bacteria strains.

Controls 3

Untreated negative controls:

yes

Remarks:

Sterile distilled water

Negative solvent / vehicle controls:

yes

Remarks:

Sterile distilled water = negative control can be regarded as vehicle control, too.

True negative controls:

yes

Remarks:

Sterile distilled water

Positive controls:

yes

Positive control substance:

other: ICR 191

Remarks:

Positive control substance when using S. typhimurium TA 1537.

Controls 4

Untreated negative controls:

yes

Remarks:

Sterile distilled water

Negative solvent / vehicle controls:

yes

Remarks:

Sterile distilled water = negative control can be regarded as vehicle control, too.

True negative controls:

yes

Remarks:

Sterile distilled water

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

Positive control substance when using S. typhimurium TA 98.

Controls 5

Untreated negative controls:

yes

Remarks:

Sterile distilled water

Negative solvent / vehicle controls:

yes

Remarks:

Sterile distilled water = negative control can be regarded as vehicle control, too.

True negative controls:

yes

Remarks:

Sterile distilled water

Positive controls:

yes

Positive control substance:

mitomycin C

Remarks:

Positive control substance when using E. coli WP2 uvrA.

Details on test system and experimental conditions:

Preparation of test substance and its negative control:
The test item was suspended in sterile distilled water. Concentration of test suspension prepared were 50 mg/ml, 15.2 mg/ml, 4.6 mg/ml, 1.4 mg/ml and 0.4 mg/ml. The test suspension was autoclaved at 121 oC for 20 min before used for study.
0.1 ml of test suspension was used for each plate, the exposure concentration was 5.00 mg/plate, 1.52 mg/plate, 0.46 mg/plate, 0.14 mg/plate and 0.04 mg/plate.

Bacteria exposure and counting procedure
Triplicate plates were used for each test concentration, negative control and positive control respectively. The minimal glucose medium with 1 x Vogel-Bonner (VB) medium E and 2% glucose was used for each plate. The total aliquots required were calculated according to the total number of plates needed for the study.
Based on plate incorporation method, 2 ml of molten top agar were dispensed to each culture tube held at 45 °C. 0.1 ml of a fresh over-night culture of the test strain, 0.1 ml or less of the test suspension / negative control / positive control, 0.2 ml Biotin/Histidine (For Salmonella typhimurium TA98, TA100, TA1535, TA1537 strains) or 0.2ml Biotin/Tryptophan (For E.coli WP2 uvrA) and 0.5 ml of 0.2M PBS (or 0.5 ml of cold S9 mixture) were then dispensed to each agar tube. The concentration of S9 fraction in S9 mixture used in each plate was 10%.
The mixture of top agar were vortexed and then poured on to a minimal glucose agar plate. The plates were allowed to harden and the inverted plates were incubated at 37 °C in a dark and vented incubator. After 48-hr incubation, the plates were checked and the revertant colonies were scored.

Evaluation criteria:

The number of revertant colonies per plate of the test substance and its respective controls were counted.

Statistics:

Student’s t-test was used to assess the significant difference between the number of revertant colonies of the test suspension and its negative control of each test strain

Results and discussion

Test results

Test results 1

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:

not determined

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not determined

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

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

 

Strain	Metabolic activation	Test suspension/ controls	No of revertant colonies in Plate 1	No of revertant colonies in Plate 2	No of revertant colonies in Plate 3	Average number of revertant colonies	Std Dev	Student’s t test (t Value)
Salmonella typhimuriumTA 1535	Without S9 activation	Test suspension 5.00 mg/plate	108	107	142	119	20	0.01
		Test suspension 1.52 mg/plate	154	245	192	197	46	0.33
		Test suspension 0.46 mg/plate	83	128	137	116	29	0.01
		Test suspension 0.14 mg/plate	126	133	113	124	10	0.01
		Test suspension 0.04 mg/plate	69	68	71	69	2	0.00
		Negative Control	283	227	201	237	42	-
		Positive control	956	909	929	931	24	-
	With S9 activation	Test suspension 5.00 mg/plate	40	38	23	34	9	0.69
		Test suspension 1.52 mg/plate	30	43	42	38	7	0.18
		Test suspension 0.46 mg/plate	28	42	35	35	7	0.43
		Test suspension 0.14 mg/plate	35	30	33	33	3	0.52
		Test suspension 0.04 mg/plate	33	31	27	30	3	0.66
		Negative Control	29	32	33	31	2	-
		Positive control	30	38	43	37	7	-

 

Strain	Metabolic activation	Test suspension/ controls	No of revertant colonies in Plate 1	No of revertant colonies in Plate 2	No of revertant colonies in Plate 3	Average number of revertant colonies	Std Dev	Student’s t test (t Value)
Salmonella typhimuriumTA 1537	Without S9 activation	Test suspension 5.00 mg/plate	6	6	7	6	1	0.09
		Test suspension 1.52 mg/plate	4	3	8	5	3	0.10
		Test suspension 0.46 mg/plate	2	3	3	3	1	0.01
		Test suspension 0.14 mg/plate	6	3	4	4	2	0.03
		Test suspension 0.04 mg/plate	4	1	1	2	2	0.01
		Negative Control	7	9	11	9	2	-
		Positive control	1088	1136	1232	1152	73	-
	With S9 activation	Test suspension 5.00 mg/plate	2	5	7	5	3	0.35
		Test suspension 1.52 mg/plate	27	11	8	15	10	0.22
		Test suspension 0.46 mg/plate	7	9	8	8	1	0.37
		Test suspension 0.14 mg/plate	7	6	8	7	1	0.81
		Test suspension 0.04 mg/plate	3	8	7	6	3	0.75
		Negative Control	6	5	9	7	2	-
		Positive control	6	11	2	6	5	-

 

Strain	Metabolic activation	Test suspension/ controls	No of revertant colonies in Plate 1	No of revertant colonies in Plate 2	No of revertant colonies in Plate 3	Average number of revertant colonies	Std Dev	Student’s t test (t Value)
Salmonella typhimuriumTA 98	Without S9 activation	Test suspension 5.00 mg/plate	8	6	8	7	1	0.07
		Test suspension 1.52 mg/plate	6	10	11	9	3	0.12
		Test suspension 0.46 mg/plate	11	16	17	15	3	0.57
		Test suspension 0.14 mg/plate	20	5	15	13	8	0.54
		Test suspension 0.04 mg/plate	10	7	8	8	2	0.09
		Negative Control	25	12	15	17	7	-
		Positive control	11	19	18	16	4	-
	With S9 activation	Test suspension 5.00 mg/plate	24	17	15	19	5	0.06
		Test suspension 1.52 mg/plate	15	17	14	15	2	0.01
		Test suspension 0.46 mg/plate	15	22	17	18	4	0.04
		Test suspension 0.14 mg/plate	24	20	25	23	3	0.14
		Test suspension 0.04 mg/plate	19	20	22	20	2	0.04
		Negative Control	27	34	25	29	5	-
		Positive control	30	36	23	30	7	-

 

 

Strain	Metabolic activation	Test suspension/ controls	No of revertant colonies in Plate 1	No of revertant colonies in Plate 2	No of revertant colonies in Plate 3	Average number of revertant colonies	Std Dev	Student’s t test (t Value)
Salmonella typhimuriumTA 100	Without S9 activation	Test suspension 5.00 mg/plate	262	408	339	336	73	0.04
		Test suspension 1.52 mg/plate	385	402	425	404	20	0.04
		Test suspension 0.46 mg/plate	444	446	308	399	79	0.19
		Test suspension 0.14 mg/plate	465	344	416	408	61	0.16
		Test suspension 0.04 mg/plate	496	592	580	556	52	0.12
		Negative Control	527	449	468	481	41	-
		Positive control	1224	1664	1094	1327	299	-
	With S9 activation	Test suspension 5.00 mg/plate	276	278	302	285	14	0.88
		Test suspension 1.52 mg/plate	346	296	261	301	43	0.58
		Test suspension 0.46 mg/plate	289	293	289	290	2	0.70
		Test suspension 0.14 mg/plate	330	302	258	297	36	0.64
		Test suspension 0.04 mg/plate	319	274	249	281	35	0.97
		Negative Control	262	324	259	282	37	-
		Positive control	456	304	304	355	88	-

 

Strain	Metabolic activation	Test suspension/ controls	No of revertant colonies in Plate 1	No of revertant colonies in Plate 2	No of revertant colonies in Plate 3	Average number of revertant colonies	Std Dev	Student’s t test (t Value)
E.coli WP2 uvrA	Without S9 activation	Test suspension 5.00 mg/plate	27	24	45	32	11	0.93
		Test suspension 1.52 mg/plate	52	40	42	45	6	0.05
		Test suspension 0.46 mg/plate	55	54	49	53	3	0.00
		Test suspension 0.14 mg/plate	23	26	34	28	6	0.26
		Test suspension 0.04 mg/plate	25	18	25	23	4	0.03
		Negative Control	33	29	36	33	4	-
		Positive control	31	44	35	37	7	-
	With S9 activation	Test suspension 5.00 mg/plate	29	26	29	28	2	0.12
		Test suspension 1.52 mg/plate	19	31	32	27	7	0.27
		Test suspension 0.46 mg/plate	32	38	31	34	4	1.00
		Test suspension 0.14 mg/plate	33	27	27	29	3	0.23
		Test suspension 0.04 mg/plate	27	27	21	25	3	0.06
		Negative Control	31	39	31	34	5	-
		Positive control	38	44	34	39	5	-

 

Applicant's summary and conclusion

Conclusions:

Strontium ferrite can be considered as non-mutagenic in the Ames test.

Executive summary:

From the study, it is concluded that the five suspensions (5.0 mg / plate, 1.52 mg / plate, 0.46 mg / plate, 0.14 mg / plate and 0.04 mg / plate) of the test item- Strontiumhexaferrite are non-mutagenic to the following bacteria strains:

a)Salmonella typhimurium TA 1535(ATCC 29629)

b)Salmonella typhimurium TA 1537(ATCC 29630)

c)Salmonella typhimurium TA 98 (NBRC 14193)

d)Salmonella typhimurium TA 100 (NBRC 14194)

e)Escherichia coli WP2 uvrA(ATCC 49979)