Phenylephrine 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: Publication published in a peer reviewed journal with limitations in design and/or reporting but otherwise adequate for assessment.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1987

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Four Salmonella typhimurium strains (TA 98, TA100, TA1535, TA1537) were exposed to the test substance (0-10000 µg/plate) with or without metabolic activation for 20 minutes at 37°C. The top agar was added and poured onto the surface of a petri dish. The histidine-revertant colonies were counted after two days of incubation at 37°C.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Phenylephrine hydrochloride

EC Number:

200-517-3

EC Name:

Phenylephrine hydrochloride

Cas Number:

61-76-7

Molecular formula:

C9H13NO2.ClH

IUPAC Name:

phenylephrine hydrochloride

Details on test material:

- Analytical purity: 99.9%
- Name of test material: Phenylephrine HCl
- Supplier: Ganes

Method

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced male Sprague-Dawley rat and male Syrian hamster livers.

Test concentrations with justification for top dose:

0, 100, 333, 1000, 3333, and 10000 µg/plate

Vehicle / solvent:

Water

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

No metabolic activation for strains: TA1535 and TA 100

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

No metabolic activation for strains: TA1537

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylenediamine

Remarks:

No metabolic activation for strain: TA98

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

With metabolic activation for all strains.

Details on test system and experimental conditions:

- Bacterial strains: All strains were obtained from Dr. Bruce Ames (university of California, Berkley) and were stored as recommended (Maron and Ames, 1983). Prior to their use for mutagenicity assays, all cultures were grown overnight with shaking at 37µC in Oxiod broth, and their phenotypes were analyzed.
- Preparation of Liver S-9 fraction: The S-9 mixes were prepared immediately prior to use and contained 10% S-9.
- Preincubation Assay: The preincubation assay was performed as described previously( Haworth et al, 1983). The test chemical, Salmonella culture, and S-9 mix or buffer were incubated at 37µC, without shaking, for 20 minutes. Chemicals known or suspected to be volatile were incubated in capped tubes. The top agar was added, and the contents of the tubes were mixed and poured onto the surface of petri dishes that contained Vogel-Bonner medium (Vogel and Bonner, 1956). The histidine-revertant (his+) colonies arising on these plates were counted following 2 days incubation at 37°C. The plates were hand-counted when a precipitate was present; otherwise automatic colony counters were used. All chemicals were initially tested in a toxicity assay to determine the appropriate dose range. The toxicity assay was performed by using TA 100 or the system developed by Waleh et al (1982). Toxic concentrations were those at which a decrease in the number of his+ colonies was seen or at which there was a clearing in the density of the background lawn. At least five doses of the chemical were tested in triplicate. Experiments were repeated at least 1 week following the initial trial. Each chemical was tested initially at half-log doses up to a dose that elicited toxicity; subsequent trials ocassionally used narrower dose increments. Chemicals that were not toxic were tested to a maximum dose of 10 mg/plate. Chemicals that were poorly soluble were tested up to a dose defined by their solubility. A maximum of 0.05 mL solvent was added to each plate. During the initial stages of the testing program, chemicals were tested with 10% S-9.

Evaluation criteria:

The data was evaluated as described previously (Hayworth et al, 1983). An individual trial was judged mutagenic (+) if a dose-related increase over the corresponding solvent control was seen, and it was judged weakly mutagenic (+W) if a low-level dose response was seen. A trial was considered questionable (?) if a dose-related increase was judged insufficiently high to justify a call of "+W" if only a single dose was elevated over the control, or if a non-dose related increase was seen. The distinction between a weak mutagenic response and a mutagenic response are highly subjective. A chemical was judged to be mutagenic (+), or weakly mutagenic (+W), if it produced a reproducible, dose related increase in his+ revertants over the corresponding solvent controls in replicate trials. A chemical was considered to be questionable (?) if a reproducible increase of his+ revertants did not meet the criteria for either a "+' or "+W" or if only a single doses produced an increase in his+ revertants in repeat trials. The chemicals were decoded only after a determination had been made regarding their mutagenicity or nonmutagenicity.

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:

not applicable

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.