2,4-dichlorobenzyl alcohol

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

No mutagenic potential of the test substance was found in in vitro experiments conducted in bacteria and mammalian cell lines including human cells.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1981-01-19 to 1981-03-13

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Experimental study with details provided, under GLP conditions.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

not specified

Principles of method if other than guideline:

An ames test was conducted.

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

other: Salmonella typhimurium TA98, TA100, TA1535, TA1537, TA1538

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver microsomal metabolic activation system (S9)

Test concentrations with justification for top dose:

62.5, 125, 250, 500, 1000 ug/plate

Vehicle / solvent:

- Vehicle: DMSO

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

other: 2-aminofluorene, neutral red

Details on test system and experimental conditions:

METHOD OF APPLICATION: semi-quantitative assay (plate)

- incubation time: 2 days
- Incubation temperature (°C): 37
- Counting: automatically, using Micro-Measurements E.T.A. colony counter
- Number of replicates: 3

Species / strain:

S. typhimurium, other: TA1535, TA1537, TA1538, TA98, TA100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

Cytotoxicity was observed starting at 500 µg/plate without S9 mix and at 1000 µg/plate with S9 mix.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Genetic toxicity

In vitro

An ames test was conducted to investigate the mutagenicity of the test substance (BASF SE.1981). The semi-quantitative assay was done with and without metabolic activation through S-9 mix prepared from liver homogenate of Aroclor 1254-pretreated male Wistar rats. The test substance was applied to Salmonella typhimurium strains TA98, TA100, TA1535, TA1537 and TA1538. Solvent controls (DMSO) and positive controls (cyclophosphamide, neutral red and 2-aminofluorene) were included in each of the triplicate experiments. No increase in the number of revertants was observed. The test substance was bacteriotoxic at 500 µg/plate and more in all tester strains without S-9 and at 1000 µg/plate in all tester strains with S-9 for metabolic activation.

 

An ames test was conducted with the test substance in Salmonella typhimurium: TA1535, TA1536, TA1537, TA1538, G46, E.coli: WP2, UvrA, CM561, CM611 (BASF SE.1974). A Diffusion bead test and Semi-quantative plate assay were done with and without metabolic activation using a rat liver microsomal fraction. Solvent controls (water, DMSO) and positive controls (N-methyl-N'-nitro-N-nitrosoguanidine, 9-aminoacridine hydrochloride, and 2-aminofluorene) were included. No evidence of in vitro mutagenicity of the test substance has been demonstrated in Esherichia coli or Salmonella typhimurium at the maximum drug levels tolerated by the test bacteria.

 

A chromosomal aberration test with and without metabolic activation with S-9 mix prepared from liver homogenate of Aroclor 1254-pretreated male Wistar rats with the test substance was conducted in cultured human lymphocytes (BASF SE.1985). Solvent controls (DMSO) and positive controls (cyclophosphamide, mitomycin C) were included. Up to 100 metaphases per dose level were scored. Lymphocytes exposed to the test substance at levels up to the maximum allowed by the cytotoxicity of the compound, i.e. 200 µg/mL in the absence of S9 and 400 µg/mL in the presence of S9, yielded similar incidences of chromosomal aberrations as the negative controls. These results indicate that the test substance is without in vitro clastogenic activity against cultured human lymphocytes.

 

A DNA repair assay with and without metabolic activation with S9 mix prepared from liver homogenate of Aroclor 1254-pretreated male Wistar rats was conducted in HeLa S3 cells to investigate the test substance potential to induce DNA repair mechanism (BASF SE.1985). Solvent controls (DMSO) and positive controls (benzo(a)pyrene, N-methyl-N'-nitro-N-nitrosoguanidine) were included. In the first assay a slight elevation in DNA-repair activity was observed at 10^-6 M in the presence of S9, and low level increases were apparent over the range 10^-7 to 10^-5 M in the absence of S9. However, none of these differences amounted to a statistically significant result and no increase occurred at higher concentrations. Therefore, they did not meet the criteria for a positive result. In the second assay a very small, non-significant, increase in repair activity at concentrations around 10^-5 in the absence of S 9 was detected. There was no effect with S9 incorporation. These observations indicated that the test substance was negative in this test system. Nevertheless, for confirmatory purposes, a third assay was conducted, using narrower dose increments and concentration ranges. On this occasion, all test concentrations gave a lower level of repair activity than their respective negative controls. These data indicate that the test substance does not induce significant DNA-repair in HeLa S3 cells and, therefore, does not bind covalently with DNA; accordingly, it has not shown genotoxic potential in this test system.

 

A test on forward mutation to 6-thioguanine resistance with and without metabolic activation with S9 mix prepared from liver homogenate of Aroclor 1254-pretreated male Wistar rats was conducted with the test substance in V79 cells (BASF SE.1986). Solvent controls (DMSO) and positive controls (7,12-dimethylbenz(a)anthracene, N-methyl-N'-nitro-N-nitrosoguanidine) were included. Cytotoxicity was observed at 400 and 800 µg/mL. No evidence of mutagenicity was seen in any test in either the absence or the presence of S9, and at test substance levels up to 400 µg/mL. This concentration proved to be extremely toxic, and cell survival was adequate in only two of the assays, one in the presence and one in the absence of S9. It was concluded that the test substance is not mutagenic in V79 cells.

 

In conclusion no mutagenic potential of the test substance was found in in vitro experiments conducted in bacteria and mammalian cell lines including human cells.

Justification for selection of genetic toxicity endpoint

A standard experiment was conducted and the results supported by several other studies.

Justification for classification or non-classification

Genetic toxicity

Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008, as amended for the seventh time in Regulation (EU) No 2015/1221. As a result based on an Ames test the substance is not considered to be classified for genetic toxicity.