Pseudoephedrine hydrochloride

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:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP compliant guideline study, available as unpublished report, limitation in study design (Salmonella strain TA102 of E. coli WP2 is lacking and only one positive control used to test efficacy of the S9-mix) but otherwise adequate for assessment.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Reference 2

Reference Type:

other: Amendment

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

, an additional tester strain (TA102 or E.coli) is lacking and only one positive control used to test efficacy of the S9-mix.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

yes

Remarks:

, an additional tester strain (TA102 or E.coli) is lacking and only one positive control used to test efficacy of the S9-mix.

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Pseudoephedrine hydrochloride

EC Number:

206-462-1

EC Name:

Pseudoephedrine hydrochloride

Cas Number:

345-78-8

Molecular formula:

C10H15NO.ClH

IUPAC Name:

2-(methylamino)-1-phenylpropan-1-ol hydrochloride

Details on test material:

- Name of test material (as cited in study report): (+)-Pseudoephedrin-HCl
- Appearance: white crystals or powder
- Storage: room temperature (darkness)

Method

Target gene:

His-locus

Species / strain

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

Male S.D. rats liver S9, induced by Aroclor 1254

Test concentrations with justification for top dose:

0, 20, 100, 500, 2500 and 5000 µg/plate

Vehicle / solvent:

aqua dest.

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

10 µg/plate

Positive control substance:

other: 2-aminoanthracene

Remarks:

All strains with metabolic activation

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

5 µg/plate

Positive control substance:

other: N-methyl-N'-nitro-N-nitroso-guanidine

Remarks:

TA 100, TA 1535; without metabolic activation

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

10 µg/plate

Positive control substance:

other: 4-nitro-o-phenylendiamine

Remarks:

TA 98; without metabolic activation

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Remarks:

100 µg/plate

Positive control substance:

9-aminoacridine

Remarks:

TA 1537; without metabolic activation

Details on test system and experimental conditions:

EXPERIMENT 1:
- METHOD OF APPLICATION: in agar (plate incorporation)
- DURATION: Exposure duration: 48 h
- NUMBER OF REPLICATIONS: 3 test plates per dose or per control
- DETERMINATION OF CYTOTOXICITY: reduced his- background growth

EXPERIMENT 2:
- METHOD OF APPLICATION: preincubation
- DURATION: Preincubation period: 20 min; Exposure duration: 48 h
- NUMBER OF REPLICATIONS: 3 test plates per dose or per control
- DETERMINATION OF CYTOTOXICITY: reduced his- background growth

Evaluation criteria:

Evaluation criteria:
In general, a substance to be characterized as positive in the Ames test has to fulfill the following requirements:
- doubling of the spontaneous mutation rate (compared to control values)
- dose-response relationship
- reproducibility of the results

Results and discussion

Test results

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

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Water solubility: complete solubility of the test substance

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments without microsomal activation in the standard plate test.

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537
0	25	126	18	15
20	27	115	20	14
100	24	109	15	13
500	21	98	17	13
2500	19	112	18	12
5000	22	103	20	10
NPD
10	783
MNNG
5		1460	1583
AAC
100				1097

 Table 2: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments with microsomal activation in the standard plate test.

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537
0	39	98	16	17
20	52	105	16	18
100	51	107	21	13
500	48	118	18	17
2500	50	107	15	18
5000	49	102	17	20
2-AA
10	658	1253	231	116

 

Table 3: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments without microsomal activation in the preincubation test.

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537
0	25	87	11	11
20	21	73	16	8
100	25	100	17	7
500	24	101	11	9
2500	29	100	11	7
5000	25	93	14	7
NPD
10	1206
MNNG		625	603
5
AAC
100				235

Table 4: Number (arithmetic mean) of colonies of histidine-prototrophic back-mutants in experiments with microsomal activation in the preincubation test.

Concentration (µg/plate)	TA98	TA100	TA1535	TA1537
0	40	89	12	11
20	44	90	15	11
100	43	98	13	7
500	36	90	14	8
2500	30	88	15	10
5000	44	95	10	5
2-AA
10	834	483	69	60

 

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

It is concluded that there is no evidence of induction of gene mutations by the test substance and its metabolites in the four S. typhimurium strains used.

Executive summary:

In a GLP compliant bacterial mutagenicity test, performed according to OECD guideline 471, 4 Salmonella typhimurium strains (TA 1535, TA 1537, TA 98, and TA 100) were used to test the mutagenic potential of the test substance both with and without metabolic activation. One standard plate test and one preincubation test were performed. In both tests strains were exposed to 0, 20, 100, 500, 2500, and 5000 µg/plate. No precipitation of the test substance was found. No bacteriotoxic effect was observed. An increased in the number of his+ revertants was not observed in the standard plate test or in the preincubation test either without S9 mix or after the addition of a metabolizing system. It was therefore concluded that the test substance is not mutagenic under these experimental conditions.