Phytosteryl Macadamiate

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:

2000-10-16 - 2001-01-26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The GLP-Study was performed according to an internationally accepted guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Test material form:

other: solid

Details on test material:

Purity: 100%

Method

Target gene:

The Salmonella typhimurium histidine (his) and the E. coli tryptophan (trp) reversion sy¬stem measures his- -» his+ and trp- trp+ reversions, respectively. The S. typhimurium and Escherichia coli strains are constructed to differentiate between base pair (TA 1535, TA 100, and WP2 uvrA) and frameshift (TA 1537, TA 98) mutations.

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:

liver microsomal activation

Test concentrations with justification for top dose:

33; 100; 333; 1000; 2500; and 5000 µg/plate

Vehicle / solvent:

Tetrahydrofurane

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

methylmethanesulfonate

other: 4-nitro-o-phenylene-diamine, 2-aminoanthracene

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:

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:

no cytotoxicity

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

Substance	Concentration				Revertants per plate
	per plate	TA1535		TA 1537		TA98		TA100		WP2uvrA
	[M9]	-	+		+	-	+	-	+	-	+
Negative control	_	12	16	13	16	23	26	139	119	45	49
Solvent control	—	8	21	8	21	22	31	111	128	32	56
4-NOPD	50.0	/	/	59	/	/	/	/	/	/	/
4-NOPD	10.0	/	/	/	/	238	/	/	/	/	/
MMS	5.0(Ml)	/	/	/	/	/	/	/	/	703	/
Sodium azide	10.0	1133	/	/	/	/	/	763	/	/	/
2-aminoanthracene	2.5	/	168	/	86	/	587	/	876	/	/
2-aminoanthracene	10.0	/	/	/	/	/	/	/	/	/	172
Test item
	3	10	13	8	12	21	26	94	107	42	60
	10	17	13	4	11	22	33	98	140	60	53
	33	12	15	7	16	19	26	102	126	58	65
	100	12	11	10	19	22	27	106	123	48	56
	333	11	11	11	18	23	32	126	122	50	54
	1000	13	14	9	15	25	28	126	123	56	64
	2500	12	16	11	15	18	30	122	125	56	73
	5000	13	17	11	19	20	29	118	121	59	64

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

During the described mutagenicity test and under the experimental conditions reported, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.

Executive summary:

The test item YOFCO MAS was assessed for its potential to induce gene mutations according to the plate incorporation test (experiment I) and the pre-incubation test (experiment II) using Salmonella typhimurium strains TA 1535, TA 1537, TA 98, and TA 100, and the Escherichia coli strain WP2 uvrA.

The assay was performed in two independent experiments both with and without liver microsomal activation. Each concentration and the controls were tested in triplicate. The test item was tested at the following concentrations:

33; 100; 333; 1000; 2500; and 5000 µg/plate

The plates incubated with the test item showed normal background growth up to 5000 µ/gplate with and without S9 mix in both experiments.

No toxic effects, evident as a reduction in the number of revertants, occurred in the test groups with and without metabolic activation.

No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with YOFCO MAS at any dose level, neither in the presence nor absence of metabolic activation (S9 mix). There was also no tendency of higher muta­tion rates with increasing concentrations in the range below the generally acknowledged border of biological relevance.

In experiment I, the number of colonies did not quite reach the lower limit of our historical control data in strain TA 1535 in solvent control. Since this deviation is rather small, this effect is judged to be based upon statistical fluctuations and has no detrimental impact on the outcome of the study.

Appropriate reference mutagens were used as positive controls. They showed a distinct increase of induced revertant colonies.

In conclusion, it can be stated that during the described mutagenicity test and under the experimental conditions reported, the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.