Corn oil (Zea mays, Gramineae), peroxidised

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:

end on 13 June 2006

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was performed according to OECD guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

adapted

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: ISO 10993

Deviations:

no

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

corn oil, peroxidised

IUPAC Name:

corn oil, peroxidised

Method

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:

enzyme fraction S9 induced in the male Sprague-Dawley rat by administation of Aroclor 1254

Test concentrations with justification for top dose:

Study 1: extract tested pure (all strains), and diluted at 50% and 25% (only TA100)
Study 2: extract tested pure (all strains)

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: 0.9% sodium chloride solution (0.9% NaCl) and 96% ethanol (extraction solvents)
- Justification for choice of solvent/vehicle: no data

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: Without S9 mix: 2-nitrofluorene (TA98), sodium azide (TA100, TA1535), 9-aminoacridine (TA1537), methylmethane sulfonate (E.coli) // With S9 mix: 2-anthramine (TA98, TA100, TA1535, E.coli), benzo[a]pyrene (TA1537)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 to 72 hours

NUMBER OF REPLICATES: triplicates

EXTRACTION CONDITIONS:
- Extraction vehicles: 0.9% sodium chloride and 96% ethanol
- Duration: 72 +/- 2 hours with agitation
- Ratio test article/vehicle: 0.2 g/mL for the 0.9% NaCl extracts (study 1 & 2) and 96% ethanol extracts (study 1), 0.4 g/mL for the 96% ethanol extracts (study 2)
- Temperature: 37°C +/- 1°C
- Aspect of the extract/condition of use: after extraction, the extracts were cooled to room temperature, vigourously shaken, decanted and used immediately

Evaluation criteria:

For each strain of bacteria used and for each concentration of the test article extracts, in the presence or absence of metabolic activation, the mean number of colonies in the dishes and the standard deviation was calculated.
After having confirmed the conformity of the controls, an evaluation of the data obtained in the presence of the test article extracts was performed according to the following scale:

Toxic effect:
- Non-significant results: if the number of colonies apparent in the presence of the test article extracts or these dilutions was greater than the half of the number of colonies apparent in the negative control.
- Significant results: if the number of colonies apparent in presence of the test article extracts or these dilutions was less or equal to half of the number of colonies apparent in the negative control.
Mutagenic effect:
- Non-significant results: if the number of colonies apparent in the presence of the test article extracts or these dilutions was less than twice the number of colonies apparent in the negative control.
- Significant results: if the number of colonies apparent in presence of the test article extracts or these dilutions was greater than or equal to twice the number of colonies apparent in the negative control.

Statistics:

not applicable

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

All the controls were in conformity with the requirements.
The values of the negative controls were in conformity with the acceptation requirements.
Standard mutagen substances tested on each strain induced a significant increase in the number of revertant colonies.

Toxic effect:
No value obtained with the test article extracted in 0.9% NaCl and in 96% ethanol was less or equal to half of the value obtained in the presence of negative control, with or without metabolic activation system.

Mutagenic effect:
No value obtained with the test article extracted in 0.9% NaCl and in 96% ethanol was greater than or equal to twice the value obtained in the presence of negative control, with or without metabolic activation system.

Precipitate: no.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1: Study 1 (0.9% NaCl extract, mean± standard deviation)

		TA 100	TA 98	TA 1535	TA 1537	WP2 uvrA
Without S9 mix	SR	126±9	38± 7	32± 3	17± 7	46± 5
	Negative control	109± 4	35± 3	32± 6	19± 3	39± 10
	Test article 100%	148± 9	51± 3	33± 11	19± 2	47± 5
	Test article 50%	145± 27
	Test article 25%	151 ± 26
	Test article 10%	137± 12
	Test article 1%	127± 11
	Positive control	604± 42	782± 28	579± 26	804± 13	526± 42
With S9 mix	SR	159± 20	62± 3	25± 5	19± 5	50± 5
	Negative control	152± 6	51± 9	22± 1	21± 3	54± 7
	Test article 100%	170± 5	62± 3	21± 7	21± 0	53± 5
	Test article 50%	162± 11
	Test article 25%	146± 9
	Test article 10%	166± 15
	Test article 1%	134±16
	Positive control	1093± 54	2260± 172	586± 28	309± 38	466± 16

SR = Spontaneous Revertants

 

Table 2: Study 1 (96% ethanol extract, mean± standard deviation)

		TA 100	TA 98	TA 1535	TA 1537	WP2 uvrA
Without S9 mix	SR	126± 9	38± 7	32± 3	17± 7	46± 5
	Negative control	117± 9	58± 5	21± 9	14± 4	50± 2
	Test article 100%	139± 10	56± 12	31± 2	12± 3	48± 5
	Test article 50%	109± 5
	Test article 25%	140± 23
	Test article 10%	111± 6
	Test article 1%	110± 14
	Positive control	604± 42	782± 28	579± 26	804±13	526± 42
With S9 mix	SR	159± 20	62± 3	25± 5	19± 5	50± 5
	Negative control	149± 12	62± 3	33± 6	25± 4	56± 10
	Test article 100%	188± 4	67± 3	39± 6	19± 2	70± 12
	Test article 50%	177± 25
	Test article 25%	179± 12
	Test article 10%	158±7
	Test article 1%	113± 14
	Positive control	1093± 54	2260±172	576± 31	309± 38	466± 16

SR = Spontaneous Revertants

 

Table 3: Study 2 (0.9% NaCl extract, mean± standard deviation)

		TA 100	TA 98	TA 1535	TA 1537	WP2 uvrA
Without S9 mix	SR	183± 17	36± 5	17± 2	26± 4	40± 5
	Negative control	193± 5	46± 6	26± 10	26± 0	37±7
	Test article 100%	203± 20	53± 14	26± 3	30± 4	42± 5
	Positive control	560± 15	516± 29	631± 21	781± 52	389±19
With S9 mix	SR	155± 17	57± 2	15±4	31±0	54± 8
	Negative control	140±14	56± 2	18± 4	29± 5	62±8
	Test article 100%	139± 12	56± 2	23± 3	30± 3	59± 5
	Positive control	1010± 37	1780± 28	451± 26	142± 16	367±38

SR = Spontaneous Revertants

 

Table 4: Study 2 (96% ethanol extract, mean± standard deviation)

		TA 100	TA 98	TA 1535	TA 1537	WP2 uvrA
Without S9 mix	SR	183± 17	36± 5	17± 2	26± 4	40± 5
	Negative control	222± 11	54± 5	24± 4	25± 4	45± 10
	Test article 100%	212± 5	61± 9	23±3	30± 4	43± 3
	Positive control	560± 15	516± 29	631± 21	781± 52	389± 19
With S9 mix	SR	155± 17	57± 2	15± 4	31± 0	54± 8
	Negative control	259± 20	65± 7	33± 5	31± 7	55± 4
	Test article 100%	264± 9	77±13	26± 4	33± 7	63± 7
	Positive control	1010± 37	1780±28	451± 26	142± 16	367± 38

SR = Spontaneous Revertants

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Under the conditions of this study, the test article extracted in 0.9% NaCl and 96% ethanol were not toxic and not mutagenic in the tested species.

Executive summary:

The Ames test was performed on the Sanyrene/Corpitol in order to evaluate the mutagenic potential of the test article. The study was conducted according to the requirements of the ISO 10993 standard: Biological evaluation of medical devices – Part 3: tests for genotoxicity, carcinogenicity and reproductive toxicity, and according to an adaptation of OECD Guideline n°471.

Extracts of the test article were prepared as follows:

- Extraction vehicles: 0.9% sodium chloride and 96% ethanol

- Duration: 72 +/- 2 hours with agitation

- Ratio test article/vehicle: 0.2 g/mL for the 0.9% NaCl extracts (study 1 & 2) and 96% ethanol extracts (study 1), 0.4 g/mL for the 96% ethanol extracts (study 2)

- Temperature: 37°C +/- 1°C

Suspensions of four strains of Salmonella typhimurium (TA98, TA100, TA1535, TA1537) and a strain of Escherichia coli WP2 uvrA were exposed to the test article extracted (up to 100%) in 0.9% NaCl and in 96% ethanol in the presence and in the absence of an exogenous metabolic activation system.

Under the conditions of this study, the test article extracted in 0.9% NaCl and 96% ethanol were not toxic and not mutagenic in the tested species. The extracts of the test article met the requirements of the test. The negative and positive controls performed as anticipated.