Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 801-773-4 | CAS number: 1550-44-3
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Genetic toxicity: in vivo
Administrative data
- Endpoint:
- in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
- Remarks:
- This genotoxicity evaluation was combined with a 28-day repeated-dose toxicity study by gavage. Only the information relevant for the micronucleus evaluation were described here (for the ‘classical’ repeated-dose toxicity study, see IU section 7.5.1).
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- FROM 29 AUGUST 2014 TO 5 MAY 2015.
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
Cross-reference
- Reason / purpose for cross-reference:
- reference to same study
- Remarks:
- The present micronucleus evaluation was done during a 28-day repeated dose toxicity study by oral route.
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2 015
- Report date:
- 2015
Materials and methods
Test guideline
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
- Version / remarks:
- 1997
- Deviations:
- not specified
- GLP compliance:
- yes (incl. QA statement)
- Type of assay:
- mammalian erythrocyte micronucleus test
Test material
- Reference substance name:
- 2,2-difluoroethyl acetate
- EC Number:
- 801-773-4
- Cas Number:
- 1550-44-3
- Molecular formula:
- C4H6F2O2
- IUPAC Name:
- 2,2-difluoroethyl acetate
- Test material form:
- liquid
- Remarks:
- Clear and colorless.
Constituent 1
Test animals
- Species:
- rat
- Strain:
- other: Crl:CD(SD).
- Details on species / strain selection:
- Rats have historically been used in safety evaluation studies for oral toxicity testing. The Crl:CD(SD) rat was selected based on consistently acceptable health status and on extensive experience with this strain at the testing facility.
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Charles River Laboratories International, Inc., Raleigh, North Carolina, U.S.A.
- Females: nulliparous and non pregnant.
- Age at study initiation: 7 weeks old.
- Weight at study initiation: the males mean body weight varied between 224.9 and 228.4 g and the females mean body weight varied between 171.6 and 176.7 g within all dose groups. The weight variation of selected animals did not exceed ± 20% of the mean weight for each sex.
- Assigned to test groups randomly: yes, the animals were distributed by computerized, stratified randomization into study groups.
- Fasting period before study: not specified.
- Housing: animals were housed in groups in solid-bottom caging with bedding and appropriate species-specific enrichment.
- Diet: all animals were fed PMI® Nutrition International LLC Certified Rodent LabDiet® 5002 ad libitum.
- Water: all animals were provided tap water ad libitum.
- Acclimation period: 6 days. The animals were released from quarantine based on normal observations for body weights and clinical signs.
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-26ºC.
- Humidity (%): 30-70%.
- Photoperiod: Animal rooms were artificially illuminated (fluorescent light) on an approximate 12-hour light/dark cycle.
IN-LIFE DATES: From 16 September 2014 to 14 October 2014.
Administration / exposure
- Route of administration:
- oral: gavage
- Vehicle:
- - Solvent used: corn oil.
- Justification for choice of solvent: the chosen solvent was among those recommended in the guideline and it was shown through sampling and analysis that the test material at 10 to 100 mg/mL in the vehicle and stored at room temperature for up to approximately 15 days was stable.
- Concentration of test material in vehicle: 0, 10, 30 and 100 mg test material/mL of vehicle.
- Amount of vehicle (gavage): 10 mL/kg bw. - Details on exposure:
- PREPARATION OF DOSING SOLUTIONS:
The test material was dissolved in corn oil. Neither the amount nor nature of any contaminants in the vehicle was expected to affect the integrity or validity of this study. Dose formulations were prepared without a correction for the sponsor reported purity. Dosing formulations of the test material were prepared and used within the established range of stability and stored at room temperature until used. - Duration of treatment / exposure:
- 29 days.
- Frequency of treatment:
- Animals were dosed daily at approximately the same time (± 2 hours) by intragastric intubation at a dose volume of 10 mL/kg body weight for 29 days. The amount of test material each animal received was based on the most recently collected body weight and the formulation concentration. Control animals were dosed with corn oil at a volume of 10 mL/kg of body weight.
- Post exposure period:
- Post exposure period is only relevant for the repeated-dose toxicity study described in details under IUCLID section 7.5.1. For micronucleus evaluation, assessments were performed on Day 4 and on the day of sacrifice (Day 30) and a post exposure period is therefore not applicable.
Doses / concentrationsopen allclose all
- Dose / conc.:
- 1 000 mg/kg bw/day
- Dose / conc.:
- 300 mg/kg bw/day
- Dose / conc.:
- 100 mg/kg bw/day
- Dose / conc.:
- 0 mg/kg bw/day
- Remarks:
- Vehicle alone.
- No. of animals per sex per dose:
- - 10 animals/sex/dose in the control and 1000 mg/kg/day test groups,
- 5 animals/sex/dose in the 100 and 300 mg/kg/day test groups. - Control animals:
- yes, concurrent vehicle
- Positive control(s):
- No positive control was used in this specific study. The study report presents the historical control data (see in section "Any other information on results incl. tables") including positive control data, demonstrating proficiency of the testing facility in the conduct of the test, as requested by the guideline.
Examinations
- Tissues and cell types examined:
- The frequency of micronuclei was analysed in the peripheral blood by analysing reticulocytes.
- Details of tissue and slide preparation:
- CRITERIA FOR DOSE SELECTION
Samples from each exposure level and the negative control were analyzed at both collection time points.
TREATMENT AND SAMPLING TIMES
Peripheral blood samples were collected by sublingual bleeding from 5 animals per sex per group. There were 2 blood collections, a bleed on day 4 and on the day of sacrifice prior to the scheduled sacrifice.
DETAILS OF SLIDE PREPARATION
Approximately 60-120 μL of blood was collected from each animal directly into a labelled microcentrifuge tube containing 350 μL of anticoagulant/diluent (anticoagulant) found in the In Vivo MicroFlow Plus® Rat Micronucleus assay kit (Litron Laboratories, Rochester, New York). The tubes were capped and inverted several times to mix the blood with anticoagulant. The blood/anticoagulant mixture was stored at room temperature for up to 6 hours or refrigerated for up to 24 hours before fixing. The blood samples were fixed in duplicate (approximately 180 μL of blood/anticoagulant mixture each) in 2 mL ultra-cold methanol and stored below -75ºC until processed.
METHOD OF ANALYSIS:
The micronucleus evaluation was conducted by flow cytometry. Whenever feasible, at least 20000 reticulocytes were analyzed per blood sample. The samples were analyzed and evaluated using the In Vivo MicroFlow Plus® Rat Micronucleus assay kit. - Evaluation criteria:
- - Toxicity was evaluated by the frequency of immature erythrocytes (%RETs) among the total erythrocytes (RETs plus NCEs).
- The frequency of micronucleated reticulocytes (%MN-RETs) was used as a measure of induction of aneugenic or clastogenic alterations by the test material.
Where:
RET: reticulocyte
NCE: normochromatic erythrocytes
MN-RET: micronucleated reticulocyte - Statistics:
- Micronucleus data was evaluated using scientific judgment taking into account both statistical and biological significance. The individual animal was considered the experimental unit. For each treatment group, the mean and standard deviation of % RETs and % MN-RETs was calculated. Data was transformed prior to analysis using an arcsine square root or Freeman-Tukey function. This transformation was appropriate for proportions since the distribution of the transformed data more closely approximates a normal distribution than does the nontransformed proportion. All micronucleus data analyses was one-tailed and conducted at a significance level of 5%. See also Table 1 in "Any other information on materials and methods incl. tables".
Results and discussion
Test results
- Key result
- Sex:
- male/female
- Genotoxicity:
- negative
- Toxicity:
- yes
- Vehicle controls validity:
- valid
- Remarks:
- The vehicle (negative) control group exhibited a response consistent with the %MN-RETs historical control data.
- Negative controls validity:
- valid
- Remarks:
- The negative control was the vehicle administered alone, see above.
- Positive controls validity:
- not applicable
- Additional information on results:
- - Induction of micronuclei: No statistically significant or biologically relevant increases in the micronucleated reticulocyte frequency (% MN-RET) were observed in any evaluated test substance treated group of male or female animals at either time point.
- Appropriateness of dose levels and route: A reduction in %RETs among the total erythrocytes was observed indicating that the test substance reached the target cells. In male rats statistically significant decreases were observed at 300 and 1000 mg/kg bw/day at day 4. In female rats, although not statistically significant, a dose related decrease in %RETs was also observed at day 4. However, no decrease in %RET was observed at day 30 in either male or female animals.
Any other information on results incl. tables
Dose formulation analysis:
The formulation analyses showed that the test material was at the targeted concentrations and stable when stored at room temperature for up to 15 days. See more details in the IUCLID section 7.5.1.
Historical control data:
Table 2: Historical Control Data
Negative control animalsa,b
Parameter | % RET- Males | % RET - Females | % MN-RET- Males | % MN-RET - Females |
Mean | 1.64 | 1.41 | 0.11 | 0.11 |
Standard deviation | 0.90 | 0.67 | 0.05 | 0.05 |
Range | 0.59 – 5.55 | 0.34 – 4.14 | 0.03 – 0.31 | 0.02 – 0.37 |
Positive control animalsa,c
Parameter | % RET- Males | % RET - Females | % MN-RET- Males | % MN-RET - Females |
Mean | 1.26 | 0.83 | 1.03 | 1.03 |
Standard deviation | 0.87 | 0.52 | 0.34 | 0.55 |
Range | 0.25 – 3.96 | 0.07 – 2.38 | 0.27 – 1.85 | 0.31 – 3.12 |
a Historical control data was compiled from studies conducted at DuPont Haskell Global Centers since 2009.
b Negative controls include all vehicles, routes of administration and sample times.
c The positive control is cyclophosphamide, administered by oral gavage. Blood was collected 48 hours after a single administration.
Tabulated results:
Table 3: Micronucleus Evaluation for Male Rats
Dose group | Group 1 0 mg/kg bw/day | Group 2 100 mg/kg bw/day | Group 3 300 mg/kg bw/day | Group 4 1000 mg/kg bw/day |
RET % : Mean SD (a) | ||||
Day 4 | 4.79 | 4.02 | 3.84* | 2.79* |
0.63 (5) | 0.87 (5) | 0.23 (5) | 0.48 (5) | |
Day 30 | 1.61 | 1.30 | 1.47 | 1.53 |
0.29 (5) | 0.37 (5) | 0.40 (5) | 0.88 (5) | |
MN-RET % : Mean SD (a) | ||||
Day 4 | 0.11 | 0.08 | 0.08 | 0.09 |
0.03 (5) | 0.03 (5) | 0.03 (5) | 0.04 (5) | |
Day 30 | 0.07 | 0.08 | 0.07 | 0.07 |
0.02 (5) | 0.05 (5) | 0.02 (5) | 0.03 (5) |
(a) Standard deviation (number of values included in calculation).
* Statistically significant difference from control at p < 0.05 by Dunnett/Tamhane-Dunnett test.
Table 4: Micronucleus Evaluation for Female Rats
Dose group | Group 1 0 mg/kg bw/day | Group 2 100 mg/kg bw/day | Group 3 300 mg/kg bw/day | Group 4 1000 mg/kg bw/day |
RET % : Mean SD (a) | ||||
Day 4 | 2.00 | 2.17 | 1.76 | 1.52 |
0.26 (5) | 0.57 (5) | 0.60 (5) | 0.38 (5) | |
Day 30 | 0.97 | 0.94 | 0.72 | 0.90 |
0.23 (5) | 0.30 (5) | 0.24 (5) | 0.14 (5) | |
MN-RET % : Mean SD (a) | ||||
Day 4 | 0.08 | 0.09 | 0.07 | 0.10 |
0.04 (5) | 0.04 (5) | 0.04 (5) | 0.03 (5) | |
Day 30 | 0.06 | 0.07 | 0.07 | 0.05 |
0.02 (5) | 0.03 (5) | 0.03 (5) | 0.03 (5) |
(a) Standard deviation (Number of values included in calculation).
Applicant's summary and conclusion
- Conclusions:
- Under the conditions of this study, 2,2-Difluoroethyl acetate showed no evidence of in vivo cytogenicity with no statistically significant or biologically relevant increase in micronucleated reticulocytes in rats.
- Executive summary:
The cytogenic potential of 2,2-Difluoroethyl acetate was investigated in the context of a 28-day repeated-dose toxicity study by gavage. This study was performed according to OECD test guidelines 407 (for the repeated-dose toxicity study) and 474 (for the micronucleus evaluation) under GLP compliance.
Four groups of male and female Crl:CD(SD) rats were administered 0, 100, 300, and 1000 mg/kg bw/day test material by gavage for 29 days consecutively (10 animals per sex in the control and 1000 mg/kg/day test groups and 5 animals per sex in the 100 and 300 mg/kg/day test groups).
Peripheral blood samples were collected from 5 animals per sex on days 4 and 30 for micronucleus evaluation by flow cytometry. The frequency of micronucleated reticulocytes (%MN RETs) was used as a measure of induction of aneugenic or clastogenic alterations by the test material. Samples from the negative control and each exposure level were analysed at both collection time points.
No statistically significant or biologically relevant increases in the micronucleated reticulocyte (RET) frequency were observed in bone marrow in any test material treated group of male or female rats at either time point. The negative control group exhibited %MN-RETs values consistent with the historical control data.
Under the conditions of this study, 2,2-Difluoroethyl acetate showed no evidence of in vivo genotoxicity with no biologically relevant increase in micronucleated reticulocytes.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.