(1R)-1-[(4R,4aR,8aS)-2,6-bis(3,4-dimethylphenyl)tetrahydro[1,3]dioxino[5,4-d][1,3]dioxin-4-yl]ethane-1,2-diol

Endpoint summary

Additional information

Gene mutation (Bacterial Reverse Mutation Assay/Ames test):

The substance Flyadd-3 (CAS No. 135861-56-2) was tested in two in vitro gene mutation studies in bacteria (Bacterial Reverse Mutation Assay/Ames Test). In the supporting study (Annex V/GLP), bacterial strains (Salmonella typhimurium TA98, TA100, TA1535, TA1537, E. Coli WP urvA) were exposed to the substance in DMSO at concentrations of 50 – 5000 µg/plate in the presence and absence of mammalian metabolic activation (Aroclor induced rat-liver S9). The substance was tested up to cytotoxic concentrations and precipitation was observed at 1500 µg/plate. There was no evidence of induced mutant colonies over background. The substance was negative in the presence and absence of metabolic activation in the Bacterial Reverse Mutation Assay/Ames test.

In the bacterial in vitro gene mutation key study (OECD 471/GLP), bacterial strains (Salmonella typhimurium TA98, TA100, TA1535, TA1537, TA 1538 and E. Coli WPurvA) were exposed to the substance in DMSO at concentrations of 100 – 5000 µg/plate in the presence and absence of mammalian metabolic activation (S9 mix). The substance was tested up to cytotoxic concentrations and precipitation was observed at 1000 µg/plate. There was no evidence of induced mutant colonies over background. The substance was negative in the presence and absence of metabolic activation in the Bacterial Reverse Mutation Assay/Ames Test.

Chromosome aberration (in vitro mammalian cell cytogenicity):

The substance Flyadd-3 (CAS No. 135861-56-2) was tested in three in vitro mammalian cytogenicity (Chromosome aberration) studies. One study was disregarded as there was no guideline indicated. Three in vitro mammalian cytogenicity (Chromosome aberration) studies (read-across from supporting substance (structural analogue or surrogate)) were also available and they were disregarded as there was no detailed test material identity indicated.

In the mammalian cell cytogenetic supporting study (Chromosome aberration; Annex V/GLP), human lymphocytes were exposed to the substance in DMSO at concentrations of 28.13 -50 µg/mL with (3 hrs) and without (20, 44 hrs) metabolic activation (Aroclor-induced rat liver S9). The substance was tested up to the solubility limit. Positive and negative controls gave expected results. There were no significant increases in aberrant metaphases between test and controls. The substance was negative in the presence and absence of metabolic activation in the in vitro mammalian cell cytogenicity (Chromosome aberration) assay.

In the mammalian cell cytogenetic key study (Chromosome aberration; OECD 473)/GLP), human peripheral blood lymphocytes were exposed to the substance in DMSO at concentrations of 3 - 50 µg/mL with (3 hrs) and without (3, 20, 44 hrs) metabolic activation (S9 mix).The substance was tested up to the solubility limit. The substance was negative in the presence and absence of metabolic activation in the in vitro mammalian cell cytogenicity (Chromosome aberration) assay.

Gene mutation (in vitro mammalian cell gene mutation):

The substance Flyadd-3 (CAS No. 135861-56-2) was tested in one in vitro gene mutation study in mammalian cells. In the mammalian cell gene mutation key study (Annex V/GLP), mouse lymphoma L5178Y cells cultured in vitro were exposed to the test substance in DMSO at concentrations of 6.25 - 50 µg/mL in the presence and absence of mammalian metabolic activation (Aroclor-induced rat liver S9). In the toxicity range-finder experiment precipitation of the test material was noted at 50 µg/mL and 100 µg/mL, both in the presence and absence of S9. Precipitation was noted in the main experiment at the highest dose of 50 µg/mL. Negative (solvent) and positive control treatments were included in each experiment in the absence and presence of S9. Mutant frequencies in negative control cultures fell within normal ranges, and clear increases in mutation were induced by the positive control chemicals. No statistically significant increases in mutant frequency were observed following treatment with the test substance at any dose level in the absence of presence of S9 in either experiment. The substance was negative in the presence and absence of metabolic activation in the in vitro mammalian cell gene mutation assay.

Justification for selection of genetic toxicity endpoint
No key study was selected as all three studies were negative.

Short description of key information:
In vitro:
Gene mutation (Bacterial Reverse Mutation Assay/Ames test): the substance Flyadd-3 (CAS No. 135861-56-2) does not induce mutagenicity using S. typhimurium TA 98, TA 100, TA 1535, TA 1537, TA 1538 and E. coli WP2 uvr A in the presence or absence of S9 mix metabolic activation (OECD 471, GLP);

Chromosome aberration (in vitro mammalian cell cytogenicity): the substance Flyadd-3 (CAS No. 135861-56-2) does not induce chromosome aberrations in human peripheral blood lymphocytes in the presence or absence of S9 mix metabolic activation (OECD 473, GLP);

Gene mutation (in vitro mammalian cell gene mutation): the substance Flyadd-3 (CAS No. 135861-56-2) does not induce gene mutations in L5178Y mouse lymphoma cells in the presence or absence of Aroclor-induced rat liver S9 metabolic activation (Annex V, GLP).

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Based on the available information in the dossier, the substance Flyadd-3 (CAS No. 135861-56-2) does not need to be classified for germ cell mutagenicity when the criteria outlined in Annex I of 1272/2008/EC are applied.