[No public or meaningful name is available]

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Not mutagenic

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In vitro gene mutation in bacteria (Ames)

The mutagenic effect of the test item was assessed according to the method descibed in the OECD guideline 471.A preliminary toxicity test was performed to define the dose levels of the test item, dissolved in water for injections, to be used for the mutagenicity experiments. The test item was then tested in two independent experiments, both with and without a metabolic activation system, the S9 mix, prepared from a liver post-mitochondrial fraction (S9 fraction) of rats induced with Aroclor 1254. 

Treatments were performed according to the direct plate incorporation method, except for the second experiment with S9 mix, which was performed according to the pre-incubation method (60 minutes, 37°C). 

Four strains of bacteria Salmonella typhimurium (TA 1535, TA 1537, TA 98 and TA 100) and one strain of Escherichia coli (WP2 uvrA) were used. Each strain was exposed to at least five dose levels of the test item (three plates/dose level). After 48 to 72 hours of incubation at 37°C, the revertant colonies were scored.

The evaluation of the toxicity was performed on the basis of the observation of the decrease in the number of revertant colonies and/or a thinning of the bacterial lawn.

The test item was freely dissolved in the vehicle (water for injections) at 50 mg/mL, after a minimum of 30 minutes of magnetic stirring. Since the test item was toxic in the preliminary test, the selection of the highest dose level to be used in the main experiments was based on the level of toxicity, according to the criteria specified in the international guidelines.

The mean number of revertants for the vehicle and positive controls met the acceptance criteria. Also, there were at least five analysable dose levels (i.e.including at least three non-cytotoxic dose levels) for each strain and test condition. The study was therefore considered to be valid. 

Experiments without S9 mix

The selected dose levels were:

- 2.06, 6.17, 18.5, 55.6, 167 and 500µg/plate for the TA 1535 and TA 100 strains in the first experiment,

- 0.686, 2.06, 6.17, 18.5, 55.6 and 167µg/plate for the TA 1537 and TA 98 strains in the first experiment,  

- 6.25, 12.5, 25, 50, 100 and 200 µg/plate for the TA 100 strain in the second experiment,

- 3.13, 6.25, 12.5, 25, 50 and 100µg/plate for the TA 1535, TA 1537 and TA 98 strains in the second experiment,

- 312.5, 625, 1250, 2500 and 5000 µg/plate for the WP2 uvrA strain in both experiments.          

No precipitate was observed in the Petri plates when scoring the revertants at any of the tested dose levels.

A strong toxicity was noted at dose levels >= 50 µg/plate in the TA 1537 and TA 98 strains, >= 55.6 µg/plate in the TA 1535 strain and >= 167 µg/plate in the TA 100 strain.

No noteworthy toxicity was noted in the WP2 uvrA strainat any of the tested dose levels.

The test item did not induce any noteworthy increase in the number of revertants, in any of the five tested strains, in either experiment. These results met the criteria of a negative response.

Experiments with S9 mix

The selected dose levels were:

-  2.06, 6.17, 18.5, 55.6, 167 and 500µg/plate for the TA 1535 and TA 100 strains in the first experiment,

- 0.686, 2.06, 6.17, 18.5, 55.6 and 167µg/plate for the TA 1537 and TA 98 strains in the first experiment,

-  2.57, 7.72, 23.1, 69.4, 208 and 625µg/plate for the TA1535, TA1537, TA 98 and TA 100 strains in the second experiment,

- 312.5, 625, 1250, 2500 and 5000 µg/plate for the WP2 uvrA strain in both experiments.

No precipitate was observed in the Petri plates when scoring the revertants at any of the tested dose levels.

A strong toxicity was noted at dose levels >= 69.4 µg/plate in the TA 1537 strain, >= 167 µg/plate in the TA 98 strain, >= 208 µg/plate in the TA 1535 strain and >= 500 µg/plate in the TA 100 strain.

No noteworthy toxicity was noted in the WP2 uvrA strainat any of the tested dose levels.

The test item did not induce any noteworthy increase in the number of revertants, in any of the five tested strains, in either experiment. These results met the criteria of a negative response.

Under the experimental conditions of this study, the test item did not show any mutagenic activity in the bacterial reverse mutation test with Salmonella typhimurium and Escherichia coli strains, either in the presence or absence of a rat liver metabolizing system.

Justification for classification or non-classification

GERM CELL MUTAGENICITY

This hazard class is primarily concerned with substances that may cause mutations in the germ cells of humans that can be transmitted to the progeny. However, the results from mutagenicity or genotoxicity tests in vitro and in mammalian somatic and germ cells in vivo are also considered in classifying substances and mixtures within this hazard class.

Category 1: Substances known to induce heritable mutations or to be regarded as if they induce heritable mutations in the germ cells of humans. Substances known to induce heritable mutations in the germ cells of humans.

Categoty 2: Substances which cause concern for humans owing to the possibility that they may induce heritable mutations in the germ cells of humans.

Classification for heritable effects in human germ cells is made on the basis of well conducted, sufficiently validated tests as In vitro mutagenicity tests such as these indicated in 3.5.2.3.8:

- in vitro mammalian chromosome aberration test;

- in vitro mammalian cell gene mutation test;

- bacterial reverse mutation tests

The substance to be registered shows negative results on the strains of Salmonella typhimurium and E. Coli under the performed test, therefore data available are conclusive but not sufficient for the classification, according to the 3.5. of the CLP Regulation n.1272/2008.