1-Propene, 2-bromo-3,3,3-trifluoro-

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

2-bromo-3,3,3-trifluoropropene did not demonstrate mutagenic potential in this in vitro cell mutation assay, under the experimental conditions described.

Link to relevant study records

Reference

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07 Feb 2012 - 16 Apr 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to official test guidelines and in compliance with GLP; on this basis the study is considered reliable without restrictions.

Qualifier:

according to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5300 - In vitro Mammalian Cell Gene Mutation Test

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.17 (Mutagenicity - In Vitro Mammalian Cell Gene Mutation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Health and Welfare. Evaluation and Licensing Division, Pharmaceutical and Medical Safety Bureau, Notification No. 1604, 1 November 1999.

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: ICH GUideline S2A (1996) and S2B (1998)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

mammalian cell gene mutation assay

Species / strain / cell type:

mouse lymphoma L5178Y cells

Details on mammalian cell type (if applicable):

- Type and identity of media: RPMI 1640, buffered with 2 mg/mL sodium bicarbonate, supplemented with 2.0 mM L-glutamine and 50 µg/mL gentamicin, supplemented with 0.1% v/v Synperonic F68, 1.0 mM sodium pyruvate and HiDHS at 10% v/v.
- Properly maintained: yes
- Periodically checked for Mycoplasma contamination: yes
- Periodically "cleansed" against high spontaneous background: yes

Metabolic activation:

with and without

Metabolic activation system:

S9 Mix

Test concentrations with justification for top dose:

Preliminary toxicity test: 3.42, 6.84, 13.67, 27.34, 54.69, 109.38, 218.75, 437.5, 875 and 1750 µg/mL

Mutation tests:
Without S9 mix (3 hours): 50, 100, 200, 225, 250, 275, 300, 325, 350, 375, 400 and 500 µg/mL
Without S9 mix (3 hours) - Additional levels: 50, 100, 125, 150, 175, 200, 225, 250, 275 and 300 µg/mL
With S9 mix (3 hours): 10, 50, 100, 150, 200, 225, 250, 275, 300, 350 and 400 µg/mL
Without S9 mix (24 hours): 200, 250, 300, 325, 350, 375, 400, 425, 450 and 500 µg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: Osmolarity and pH of solutions prepared using DMSO as the solvent were assessed prior to the start of testing. DMSO was found not to cause fluctuations in osmolarity greater than 50 mOsm/kg, nor was it found to cause fluctuations in pH greater than 1.0 unit.

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

methylmethanesulfonate

Remarks:

MMS used in the absence of S9 mix; BaP used in the presence of S9 mix

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: Preliminary test: 3 hours with or without S9 mix; 9 hours without S9 mix. Main test 1: 3 hours in the presence and absence of S9 mix. Main test 2: 24 hours in the absence of S9 mix.
- Expression time (cells in growth medium): Sampled at 24 and 48 hours

NUMBER OF REPLICATIONS: Duplicate cultures for each concentration; quadruplicate cultures for each vehicle control

NUMBER OF CELLS EVALUATED: 2 x 10^3 cells per well in selective medium on 96-well plates.

DETERMINATION OF CYTOTOXICITY
- Method: Relative suspension growth and relative total growth

Evaluation criteria:

The test agent was regarded as negative if:

The mean mutant frequency of all test concentrations was less than the sum of the mean concurrent vehicle control mutant frequency and the GEF.

If the mutant frequency of any test concentrations exceeded the sum of the mean concurrent solvent control mutant frequency and the GEF, a linear trend test was applied:
If the linear trend test was negative, the result was regarded as negative.
If the linear trend test was positive, this indicated a positive, biologically relevant response.

The Global Evaluation Factor (GEF) applied was 126 x 10^-6 (Moore et al, 2006)

Species / strain:

mouse lymphoma L5178Y cells

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: No fluctuations in the pH of the medium of more than 1.0 unit were observed at 1750 µg/mL compared with the vehicle control
- Effects of osmolality: No fluctuations in the osmolarity of the medium of more than 50 mOsm/kg were observed at 1750 µg/mL compared with the vehicle control
- Precipitation: No precipitate (assessed visually at the end of treatment for each test) was observed

RANGE-FINDING/SCREENING STUDIES:
The preliminary toxicity test was conducted at concentrations between 3.42 to 1750 µg/mL. For a 3-hour exposure in the presence and absence of S9 mix, relative suspension growth (RSG) ranged from 113% to 1% in the absence of S9 mix and from 101% to 0% in the presence of S9 mix. Following continuous 24-hour exposure RSG ranged from 147% to 0% using the same concentration ranges as the 3-hour exposure. The main test concentrations were established on the basis of this preliminary work.

Conclusions:

Interpretation of results (migrated information):
negative

It was concluded that 2-bromo-3,3,3-trifluoropropene did not demonstrate mutagenic potential in this in vitro cell mutation assay, under the experimental conditions described.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

An Ames test, an in vitro chromosome aberration test in human peripheral blood lymphocytes and an in vitro mammalian cell gene mutation test (mouse lymphoma assay) were performed with 2-Bromo-3,3,3 -trifluoropropene. In either three tests, evidence of in vitro clastogenic or mutagenic activities were not detected.

Justification for selection of genetic toxicity endpoint

The study was conducted according to official test guidelines and in compliance with GLP

Justification for classification or non-classification

 In vitro tests with 2-Bromo-3,3,3 -trifluoropropene were all negative.

Based on these findings, the notified substance 2-Bromo-3,3,3 -trifluoropropene is not expected to be a genotoxic substance and therefore is not classified in accordance with the CLP Regulation (EC) No 1272/2008.