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EC number: 256-974-4 | CAS number: 51115-67-4
- 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
Acute Toxicity: oral
Administrative data
- Endpoint:
- acute toxicity: oral
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 29 January - 25 February 1986
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study
- Remarks:
- OECD 420
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 1 987
- Report date:
- 1987
Materials and methods
Test guideline
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)
- Deviations:
- yes
- Remarks:
- One animal was outside the pre-fasted body weight range quoted in the protocol. This deviation was considered not to have affected the integrity of the study.
- GLP compliance:
- yes
- Test type:
- up-and-down procedure
- Limit test:
- yes
Test material
- Reference substance name:
- 2-isopropyl-N,2,3-trimethylbutyramide
- EC Number:
- 256-974-4
- EC Name:
- 2-isopropyl-N,2,3-trimethylbutyramide
- Cas Number:
- 51115-67-4
- Molecular formula:
- C10H21NO
- IUPAC Name:
- 2-isopropyl-N,2,3-trimethylbutyramide
Constituent 1
- Specific details on test material used for the study:
- SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: WS23, white powder, S15100-T01
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: all formulations used within 4 hours of preparation and assumed to be stable unless specified by study sponsor. The test article was formulated in corn oil.
Test animals
- Species:
- rat
- Strain:
- Crj: CD(SD)
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Charles River
- Females non-pregnant: yes
- Age at study initiation: the animals were aged between 6 and 10 weeks
- Weight at study initiation: the males were between 263 and 363 g. The females were between 170 and 275 g.
- Fasting period before study: overnight fasting before dosing
- Housing: groups in 5 in stainless steel wire mesh cages cages
- Diet (e.g. ad libitum): except the overnight fasting before dosing, animals were allowed free access to food. The food was re-introduced 1-hr after treatment.
- Water (e.g. ad libitum): yes - tap water via bottles ad libitum
- Acclimation period: minimum 3 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-25°C
- Humidity (%): 40-70%
- Air changes (per hr): minimum 15 air changes per hour
- Photoperiod (hrs dark / hrs light): fluorescent, 12 hours each day (between 6:00 AM - 18:00 PM)
Administration / exposure
- Route of administration:
- oral: gavage
- Vehicle:
- corn oil
- Details on oral exposure:
- VEHICLE
- Vehicle: corn oil
- Amount of vehicle (if gavage): 10 ml/kg
MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg - Doses:
- Screening study - doses range between 250 and 5000 mg/kg
Definitive study - doses range between 255 and 1000 mg/kg - No. of animals per sex per dose:
- Screeenign study - 1 male and 1 female per single oral dose
Definitive study - 5 males and 5 females per single oral dose - Control animals:
- no
- Details on study design:
- Experimental design:
Screening study - groups of one male and one female rat were dosed with 1 of 5 appropriately spaced dose levels, with 5000 mg/kg as the highest dose.
Animals were observed for 7 days. The mortality was recorded.
As the deaths were noted in the screening study, a definitive study was applied
Definitive study - five females and five males were used per dose. Dose levels were based on results from the screening study.
- Clinical observations: 1 and 4 hours after dosing, then daily for 14 days
- Body weight observation: day before treatment (day 1), day of dosing, days 8 and 15 and at death
- Necropsy of survivors was performed. All animals were subjected to a gross necropsy examination.
No tissues were retained. Animals surviving the 14 day observation period were killed by exposure to high levels of carbon dioxide.
- Other examinations performed: clinical signs, body weight
- Statistics:
- The acute oral median lethal dose and 95% fiducial limits for all animals was calculated using a probit analysis (Finney, D.J. (1971), Probit Analysis, 3rd ed. Cambridge: Cambridge University Press.
Results and discussion
- Preliminary study:
- During the screening study 5 groups of animals, each of 2 animals (1 male and 1 female) were dosed with 5000, 2000,1000, 500 and 250 mg/kg. The mortalities indicated an oral median lethal dose between 250 and 1000 mg/kg.
Effect levelsopen allclose all
- Key result
- Sex:
- female
- Dose descriptor:
- LD50
- Effect level:
- 490 mg/kg bw
- Based on:
- other:
- Remarks on result:
- other:
- Remarks:
- 95% fiducial limits cannot be determined
- Key result
- Sex:
- male
- Dose descriptor:
- LD50
- Effect level:
- 533 mg/kg bw
- Based on:
- other:
- 95% CL:
- ca. 533 - ca. 694
- Mortality:
- The animals were observed for mortality only during the screening study. The mortalities indicated an oral median lethal dose between 250 and 1000 mg/kg.
During the definitive study, a total of 20 animals (12 male, 8 female) died during the study period.
Definitive study - 2 animals treated with 1000 mg/kg were found dead 4 hours after treatment. The majority of animals were found dead 1 day after treatment. Deaths continued until 3 days after treatment. - Clinical signs:
- other: Definitive study - marked clinical signs were observed in all male animals treated at 360 to 1000 mg/kg during the day of treatment. Thereafter fewer clinical signs were observed until day 5 when all surviving animals treated at 510 mg/kg were normal. Two
- Gross pathology:
- All animals necropsied at termination were unremarkable.
Necropsy of animals dying during the study showed abnormal appearance of the lungs, liver, kidneys, stomach, G.I. tract and bladder. Common findings in these animals were dark lungs, dark liver, distended stomach, discoloured G.I. tract and distended bladder.
Any other information on results incl. tables
Table 3. Mortalities in the screening study |
|||||
Group number |
Dose Level (mg/Kg) |
Male mortalities |
Female mortalities |
Total |
% |
1 |
5000 |
1/1 |
1/1 |
2/2 |
100 |
2 |
2000 |
1/1 |
1/1 |
2/2 |
100 |
3 |
1000 |
1/1 |
1/1 |
2/2 |
100 |
4 |
500 |
0/1 |
1/1 |
1/2 |
50 |
5 |
250 |
0/1 |
0/1 |
0/2 |
0 |
Table 3. Mortalities in the definitive study |
||||
Group number |
Dose Level (mg/Kg) |
Male mortalities |
Female mortalities |
% |
6 |
360 |
0/5 |
- |
0 |
7 |
510 |
3/5 |
- |
60 |
8 |
720 |
4/5 |
- |
80 |
9 |
1000 |
5/5 |
- |
100 |
10 |
255 |
- |
0/5 |
0 |
11 |
360 |
- |
0/5 |
0 |
12 |
500 |
- |
3/5 |
60 |
13 |
700 |
- |
5/5 |
100 |
Applicant's summary and conclusion
- Interpretation of results:
- Category 4 based on GHS criteria
- Conclusions:
- This study was performed to determine the acute oral median lethal dose (LD50) of WS-23 in the rat. The acute oral median lethal dose and 95% fiducial limits were calculated by a probit method. The following values were obtained:
Males (only) - 533 mg/kg (398 - 694)
Females (only) - 490 mg/kg (95% fiducial limits could not be calculated for this sex)
Based on these results, WS-23 is classified as acute oral toxicity cat. 4 according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008. - Executive summary:
This study was performed to determine the acute oral median lethal dose (LD50) of WS23 in the rat.
The animals were aged between 6 and 10 weeks and were acclimatised to the laboratory environment for at least 3 days. Before starting the study, all animals were examined for signs of ill health or injury. All animals appeared healthy and no animals were discarded.
In the screening study, 5 groups of animals, each of 2 animals (1 male, 1 female) were dosed with 5000, 2000,1000, 500 and 250 mg/kg. The animals were observed for mortality only in this phase of the study. Frequent observations were made for 7 days. Individual body weights were recorded on the day of treatment to allow the calculation of individual treatment volumes. No necropsies were performed. The mortalities indicated an oral median lethal dose between 250 and 1000 mg/kg.
Based on the results of the screening study, 8 groups, each of 5 fasted rats (5 males or 5 females) were treated with a single oral dose at dose levels between 255 and 1000 mg/kg. All animals were observed for overt signs of toxicity or behavioural change at 1 and 4 hours after treatment and subsequently once daily for 14 days. All gross or visible toxic or pharmacological effects were recorded. Marked clinical signs were observed in a majority of female animals treated at 255 to 700 mg/kg during the day of treatment. Thereafter fewer clinical signs were observed until day 3 when all animals treated at 255 and 360 mg/kg were normal. The 2 surviving animals treated at 500 mg/kg were normal on day 5.
The acute oral median lethal dose and 95% fiducial limits were calculated by a probit method. The following values were obtained:
Males (only) - 533 mg/kg (398 - 694)
Females (only) - 490 mg/kg (95% fiducial limits could not be calculated for this sex)
Based on these results, WS-23 is classified as acute oral toxicity cat. 4 according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.
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