D-ribose

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

December 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

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

Reference substance name:

D-ribose

EC Number:

200-059-4

EC Name:

D-ribose

Cas Number:

50-69-1

Molecular formula:

C5H10O5

IUPAC Name:

D-ribose

Test material form:

solid: particulate/powder

Details on test material:

Dry powder, white to slightly yellow

Method

Target gene:

HIS, rfa, uvrB, R-factor

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:

other: HIS G46/C3076/D3052

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

other: Trp

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

0; 62; 185; 556; 1667; 5000 µg/L
top dose in accordance to test guideline in the absence of cytotoxicity.

Vehicle / solvent:

Water

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

benzo(a)pyrene

ethylnitrosurea

other: 2-aminoanthracene, 2.0µg/plate

Results and discussion

Test results

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

Positive controls validity:

valid

Any other information on results incl. tables

positive control mutagens
strain	in the absence of the S9-mix	in the presence of the S9-mix
TA 1535	sodium azide: 1.0 tg/plate	2-aminoanthraTéene: 2.0 ug,^,Iplate
TA 1537	9-aminoacridine: 801.14/plate	benzo(a)pyrene: 4.0 ..tg/plate
TA 98	2-nitrofluorene: 2.0 µg/plate	2-aminoanthracene: 2.0 µg/plate
TA 100	sodium azide: 1.0 µg/plate	2-aminoanthracene: 2.0 ug/91ate
WP2uvrA	N-ethyl-N-nitrosourea: 100 gg/plate	2-aminoanthracene: 80 µg/plate

Dose		TA1535		TA1537		TA98		TA100		e.coli
µg/L		S9-	S9+	S9-	S9+	S9-	S9+	S9-	S9+	S9-	S9+
		16	14	14	15	22	46	121	128	27	23
		13	12	16	15	29	34	121	129	28	24
		17	16	9	19	26	36	155	127	22	33
0	Mean	15	14	13	16	26	39	132	128	26	27
	Sd	2	2	4	2	4	6	20	1	3	6
		22	8	9	11	20	46	126	131	20	19
		14	11	17	9	31	45	143	143	26	28
		17	14	11	17	22	36	128	118	13	24
62	Mean	18	11	12	12	24	42	132	131	20	24
	Sd	4	3	4	4	6	6	9	·    13	7	5
		22	6	9	12	27	28	126	121	27	27
		18	8	16	18	33	40	122	104	31	19
		18	10	13	19	35	45	132	123	37	18
185	Mean	19	8	13	16	32	38	127	116	32	21
	Sd	2	2	4	4	4	9	5	10	5	5
		19	11	11	16	25	37	122	143	19	28
		20	12	12	17	14	27	100	121	26	29
		14	22	18	20	24	42	126	124	25	26
556	Mean	18	15	14	18	21	35	116	129	23	28
	Sd	3	6	4	2	6		14	12	4	2
		22	14	17	15	25	58	122	129	28	36
		12	9	8	16	38	31	132	132	25	19
		17	6	9	24	33	35	118	138	27	22
1667	Mean	17	10	11	18	32	41	124	133	27	26
	Sd	5	. 4	5	5	7	15	7	5	2	9
		13	7	8	18	19	52	99	124	22	20
		21	9	8	7	19	46	126	140	23	22
		14	12	9	9	27	41	141	139	30	24
5000	Mean	16	9	8	11	22	46	122	134	25	22
	Sd	4	3	1	6	5	6	21	9	4	2
		387	212	769	270	888	1091	406	1577	212	944
		398	216	707	219	873	1052	423	1453	173	950
		411	222	633	192	980	981	397	1485	194	1049
Pos.C.	Mean	399	217	703	227	914	1041	409	1505	193	981
	Sd	12	5	68	40	58	56	13	64	20	59

Applicant's summary and conclusion

Conclusions:

It is concluded that the results obtained with the test substance D-Ribose in Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100, and in the Escherichia coli strain WP2 uvrA, in both the absence and the presence of the S9-mix, indicate that D-Ribose was not mutagenic under the conditions employed in this study.

Executive summary:

The results of the mutagenicity assays are shown in Table 1 and 2.

Two independent assays were performed with all strains in both the absence and the presence of the S9-mix with five different concentrations of the test substance, ranging from 62 -5000 lag/plate (first assay) and 313 -5000 µg/plate (second assay). The test compound was dissolved in water. Negative controls (solvent) and positive controls were run simultaneously with the test substance.

A slight decrease in the mean number of revertant colonies observed in some strains in the second test indicates possible toxicity to these strains by the test substance D-Ribose.

In both assays, in the absence and the presence of the S9-mix and in all strains, D-Ribose did not cause a two-fold or greater increase in the mean number of revertant colonies appearing in the test plates compared to the background spontaneous reversion rate observed with the negative control, and did not give evidence of a dose-response relationship.

The mean number of his + and trp+ revertant colonies of the negative controls were within the acceptable range, and the positive controls gave the expected increase in the mean number of revertant colonies.