[1,1':3',1''-Terphenyl]-2'-ol, 5',5''''-(2,2,2-trifluoro-1-methylethylidene)bis-

Endpoint summary

Additional information

An Ames Test was conducted according to OECD Testing Guideline 471 (BASF 2008). Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100 as well as E. coli WP2 uvr A were treated with 0-5000 µg/plate Ligand TFME-DPP with or without metabolic activation. A weak bacteriotoxic effect was observed in the standard plate test at ≥2500 µg/plate and in the preincubation assay bacteriotoxic tendencies were noted at ≥1250µg/plate. An increase in the number of his+ or trp+ revertants was not observed in the standard plate test or in the preincubation test either without S9 mix or after the addition of a metabolizing system. Therefore, Ligand TFME-DPP was not mutagenic in the Salmonella typhimurium/Escherichia coli reverse mutation assay under the conditions chosen.

 

An HPRT Test was conducted according to OECD Testing Guideline 476 (BASF 2015). CHO cells were treated with 0-100 µg/mL Ligand TFME-DPP in the absence of metabolic activation and with 0-80 µg/mL Ligand TFME-DPP if S9 mix was added for metabolic activation. Subsequently, the relative and absolute cloning efficiency as well as the mutant frequency were determined. No cytotoxicity was observed in the cultures, although Ligand TFME-DPP was tested up to precipitating concentrations. No increased mutant frequencies were observed in the presence or absence of S9 mix at any test substance concentration compared to vehicle controls. Therefore, Ligand TFME-DPP is not a mutagenic substance in the HPRT locus assay using CHO cells under the experimental conditions chosen.

 

The clastogenic potential of Ligand TFME-DPP was tested in an in vitro Micronucleus Test (MNT) according to OECD testing guideline 487 (BASF 2015). Chinese hamster lung fibroblasts (V79 cells) were treated with 0-200 µL/mL Ligand TFME-DPP (without metabolic activation) and with 0-100 µL/mL Ligand TFME-DPP (with metabolic activation). With and without S9 mix the cells were exposed for 4h, followed by 20 hours recovery. Additionally, a third treatment group was not treated with S9 mix and exposed for 24 hours without subsequent recovery and a fourth treatment group was exposed to Ligand TFME-DPP in the presence of S9 mix for 4 hours followed by 40 hours recovery time. Following treatment, the relative population doubling (RPD) and proliferative index (CBPI) was not affected up to the highest concentration tested. No increase in micronucleus formation was observed upon treatment of cells with Ligand TFME-DPP. Therefore, Ligand TFME-DPP is not clastogenic or aneugenic in the in vitro MNT under the conditions chosen.

Justification for selection of genetic toxicity endpoint
study according to GLP and guideline

Short description of key information:
Ames Test (OECD TG 471): negative
HPRT Test (OECD TG 476): negative
MNT in vitro Test (OECD TG 487): negative

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

The current data do not fulfill the criteria for classification according to Regulation (EC) 1272/2008 or Regulation 67/548/EEC, thus a non-classification for Ligand TFME-DPP is warranted.