Benzyl alcohol

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:

data from handbook or collection of data

Justification for type of information:

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES are commonly accepted as trustworthy and useful reference books

Data source

Reference

Reference Type:

review article or handbook

Title:

Unnamed

Year:

1989

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

only 4 strains used instead of the 5 required by the current guideline

Principles of method if other than guideline:

Preincubation assay as described by Haworth et al (1983): Environ Mutagen 5[Suppl 1], 3-142

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Benzyl alcohol

EC Number:

202-859-9

EC Name:

Benzyl alcohol

Cas Number:

100-51-6

Molecular formula:

C7H8O

IUPAC Name:

phenylmethanol

Test material form:

liquid

Method

Target gene:

histidine locus

Species / strain

Species / strain / cell type:

other: Salmonella typhimurium TA 98, TA100, TA1535, TA1537

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

S9-liver fractions of male Sprague-Dawley rats and male Syrian hamsters induced with Ariclor 125

Test concentrations with justification for top dose:

0, 100, 333, 1000, 3333, 3000, and 6666 µg/plate

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

no

Positive control substance:

9-aminoacridine

sodium azide

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

Details on test system and experimental conditions:

Pre-test: All chemicals were initially tested with strain TA100 in the presence and the absence of the metabolic activation systems, over a wide dose range with an upper limit of 10 mg/plate, or less when solubility problems were encountered.

To each of 13 x 100-mm test tubes maintained at 37°C were added in the following order: 0.5 ml of S-9 mix or 0.1 M P04 buffer (pH 7.4), 0.05 ml of the overnight culture, and 0.05 ml of solvent or chemical dilution. The mixture was mixed and allowed to incubate without shaking at 37°C for 20 min, at which time 2.5 ml of molten (45°C) top agar supplemented with 0.5 mM L-histidine and 0.5 mM D-biotin were added. The contents of the tubes were mixed and poured onto 25 ml of minimal glucose bottom agar [Vogel and Bonner, 1956] in 15 x 100-mm plastic petri dishes (Falcon Muta-Assay, 1028). When the top agar had solidified, the plates were inverted and incubated at 37°C for 48 hr.
Concurrent solvent and positive controls were tested with and without the metabolic activation systems. At least five dose levels of the chemicals were tested,
with three plates per dose level. All assays were repeated (as described above) no less than 1 wk after completion of the initial test.
Nontoxic chemicals were tested in the initial experiment up to the 10 mg/plate dose level, or to a level determined by their solubility. Toxic chemicals were tested up to a high dose which exhibited some degree of toxicity. As a rule, at least one toxic dose was incorporated into the first mutagenicity test; the repeat test(s) occasionally had the doses adjusted so that an apparent toxic dose was not reached.

DETERMINATION OF CYTOTOXICITY
Cytotoxicity was evidenced by one or more of the following phenomena: appearance of his(neg) pinpoint colonies, reduced numbers of revertant colonies per plate, or thinning or absence of the bacterial lawn.

Evaluation criteria:

positive response: dose-related reproducible increase in the number of revertants over background even if the increase was less than twofold
questionable response: absense of a clear-cut dose-reated increase of revertants or when the response was not reproducible
negative response: when no increase in the number of revertants was elicited by the chemical

Statistics:

no data

Results and discussion

Test results

Species / strain:

other: S. typhimurium TA 98, TA 100, TA 1535, TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Benzyl alcohol was not mutagenic when tested by the preincubation protocol in the presence or absence of exogenous metabolic activation in Salmonella typhimurium strains TA98, TA100, TA1535, or TA1537.

Executive summary:

A bacterial reverse mutation assay (Ames) according to the protocol of Haworth (1983) was conducted using the four Salmonella typhimurium strains TA 1535, TA 1537, TA 98, and TA 100 with and without a metobolic activating system. The doses were based on a preliminary dose-setting experiment and ranged between 100 and 6666 µg/plate. Benzyl alcohol was not mutagenic when tested by the preincubation protocol in the presence or absence of exogenous metabolic activation in Salmonella typhimurium strains TA98, TA100, TA1535, or TA1537.