1,2-Benzenediol, 4-(2-hydroxyethyl)-

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:

2013

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Study was conducted to OECD guidlines 471 Bacterial Reverse Mutation test and was in published literature rather than a offical study report

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

not specified

Remarks:

report was a detailed publications conducted to OECD guidelines and well conducted but not indicated if according to GLP

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

1

Reference substance name:

4-(2-hydroxyethyl)benzene-1,2-diol

EC Number:

600-704-3

Cas Number:

10597-60-1

Molecular formula:

C8H10O3

IUPAC Name:

4-(2-hydroxyethyl)benzene-1,2-diol

Method

Target gene:

Salmonella typhimurium TA 100, TA98, TA1535, and TA1537 strains and Escherichia coli WP2(pKM101))

Metabolic activation:

with and without

Metabolic activation system:

The S9 mix preparation was performed according to Ames et al.[8]. In brief, an appropriate quantity of S9 supernatant was thawed and mixed with S9 cofactor solution to result in a final protein
concentration of 0.75 mg/mL in the cultures

Test concentrations with justification for top dose:

5 concentrations (C5, 5 "L/plate; C4, 1.67 "L/plate; C3, 0.56 "L/plate; C2, 0.19 "L/plate; and C1, 0.06 "L/plate) with and without S9 under the directincorporation (main study) and the pre-incubation (confirmatory study) procedures

Details on test system and experimental conditions:

Plates were incubated for 48 h at 37 ◦C and colonies were counted. The assay was performed by triplicate along with vehicle and reference item controls. Each bacterial strain culture was mixed with the test item either with metabolic activation system mix (S9) or without metabolic activation system mix (PBS was used instead). In the direct incorporation procedure the mixture was immediately poured over a minimal agar medium plate and incubated at 37 ◦C for 48 h, whereas in the pre-incubation procedure, the mixture was incubated for 20 min at 37 ◦C prior to be poured over the minimal agar medium plate. Cytotoxicity evaluation of HT was based on the decrease in the number of revertant colonies, or a clearing or diminution of the background lawn

Statistics:

Statistical analysis was performed to determine the mean values of revertants/plate using a non-parametric method (Kolmogorov–Smirnov test) and the SALANAL statistical package software. Comparisons between groups were made using
Mann–Whitney U test

Results and discussion

Test results

Test results 1

Key result

Species / strain:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

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

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Remarks:

Main Study

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Remarks:

Main study

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

not determinable

Applicant's summary and conclusion

Executive summary:

Cytotoxicity evaluation of HT was performed in the S. typhimurium TA 100 strain by the direct incorporation procedure with 5 concentrations prepared by 1:3 serial dilutions starting at 50.0 µL/mL up to 0.6 µL/mL. No cytotoxic activity was observed in the bacterial system at a HT concentration of 50.0 µL/mL. None of the concentrations assayed for HT showed an increase in the R value either with or without S9 metabolic activation regardless of the procedure. No dose response for HT was observed in any of the tested bacterial strains