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EC number: 203-438-2 | CAS number: 106-88-7
- 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
Endpoint summary
Administrative data
Description of key information
In a study similar to OECD TG 401, an approximative oral LD50 value of about 913 mg/kg bw for male and female rats was reported.
In a study similar to OECD TG 403, rats inhaled the test material in a concentration of 6.3 mg/L as a vapour for 4 hours. No mortalities and no symptoms were observed. Thus, the LC50 was greater than 6.3 mg/L for 4 hours.
An acute dermal LD50 value of ca.1469 mg/kg bw was found for male rabbits.
Key value for chemical safety assessment
Acute toxicity: via oral route
Link to relevant study records
- Endpoint:
- acute toxicity: oral
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 1975
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study with acceptable restrictions
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 401 (Acute Oral Toxicity)
- GLP compliance:
- no
- Test type:
- standard acute method
- Limit test:
- no
- Species:
- rat
- Strain:
- Sprague-Dawley
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: BASF SE
- Age at study initiation: no data
- Weight at study initiation: The mean body weight of male animals was 206 g, the mean body weight of female animals was 174 g - Route of administration:
- oral: gavage
- Vehicle:
- CMC (carboxymethyl cellulose)
- Details on oral exposure:
- The test substance was given as an emulsion in 0.5% aqueous CMC solution.
Observation period: 7 resp. 14 days - Doses:
- 100, 464, 681, 1000, 1210, 1470, 1780, 2150, 4640, 10000 µL/kg
- No. of animals per sex per dose:
- 5 and/or 10 (see mortality table)
- Control animals:
- not specified
- Details on study design:
- - Duration of observation period following administration: 7 resp. 14 days
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight - Statistics:
- no data
- Key result
- Sex:
- male/female
- Dose descriptor:
- approximate LD50
- Effect level:
- ca. 913 mg/kg bw
- Remarks on result:
- other: Calculated with density of 0.83 g/cm3
- Sex:
- male/female
- Dose descriptor:
- approximate LD50
- Effect level:
- ca. 1 100 other: µL/kg
- Remarks on result:
- other: original value
- Mortality:
- yes (see table below)
- Clinical signs:
- other: slight apathy, partially staggering, dyspnoea, diarrheic feces, exsiccosis, abdominal and lateral position
- Gross pathology:
- acute heart dilatation (both sides), acute congestive hyperemia, intra-abdominal adhesions of the stomach, thickened wall of the forestomach, partially formation of diverticulum
- Interpretation of results:
- Category 4 based on GHS criteria
Reference
Mortality:
Dose (µL/kg) | Concentration (%) | No. of animals | dead within | ||||
1 hour | 24 hours | 48 hours | 7 days | 14 days | |||
10000 | 35 | 5 males | 0/5 | 5/5 | 5/5 | 5/5 | |
5 females | 0/5 | 5/5 | 5/5 | 5/5 | |||
4640 | 35 | 5 males | 0/5 | 5/5 | 5/5 | 5/5 | |
5 females | 0/5 | 5/5 | 5/5 | 5/5 | |||
2150 | 30 | 10 males | 0/10 | 10/10 | 10/10 | 10/10 | |
10 females | 1/10 | 10/10 | 10/10 | 10/10 | |||
1780 | 15 | 5 males | 0/5 | 5/5 | 5/5 | 5/5 | |
5 females | 0/5 | 5/5 | 5/5 | 5/5 | |||
1470 | 15 | 10 males | 0/10 | 10/10 | 10/10 | 10/10 | |
10 females | 0/10 | 10/10 | 10/10 | 10/10 | |||
1210 | 15 | 5 males | 0/5 | 2/5 | 2/5 | 2/5 | |
5 females | 0/5 | 5/5 | 5/5 | 5/5 | |||
1000 | 15 | 5 males | 0/5 | 1/5 | 1/5 | 1/5 | |
5 females | 0/5 | 0/5 | 0/5 | 0/5 | |||
681 | 6 | 5 males | 0/5 | 0/5 | 0/5 | 0/5 | |
5 females | 0/5 | 0/5 | 0/5 | 0/5 | |||
464 | 6 | 5 males | 0/5 | 0/5 | 0/5 | 0/5 | |
5 females | 0/5 | 0/5 | 0/5 | 0/5 | |||
100 | 1.5 | 5 males | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
5 females | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed
- Dose descriptor:
- LD50
- Value:
- 913 mg/kg bw
- Quality of whole database:
- study similar to OECD 401
Acute toxicity: via inhalation route
Link to relevant study records
- Endpoint:
- acute toxicity: inhalation
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- comparable to guideline study with acceptable restrictions
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- OECD Guideline 403 (Acute Inhalation Toxicity)
- Principles of method if other than guideline:
- dynamic inhalation method with analytical and nominal determination of the concentration.
- GLP compliance:
- no
- Test type:
- standard acute method
- Limit test:
- yes
- Species:
- rat
- Strain:
- Sprague-Dawley
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: WIGA Sulzfeld, Germany
- Age at study initiation: no data
- Weight at study initiation: 185 +/- 15 g
- Housing: no data
- Diet: ad libitum, Standard diet
- Water: ad libitum
- Acclimation period: no data - Route of administration:
- inhalation: vapour
- Vehicle:
- other: unchanged (no vehicle)
- No. of animals per sex per dose:
- 10
- Control animals:
- yes
- Details on study design:
- - Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The body weight of the animals were checked before starting of the study, after 7 days and at the end of the observation period. Clinical signs and mortality were checked daily.
- Necropsy of survivors performed: yes; After the 14-day observation period the animals were killed and a pathological-anatomical evaluation was done. - Statistics:
- none
- Key result
- Sex:
- male/female
- Dose descriptor:
- LC50
- Effect level:
- > 6.3 mg/L air (analytical)
- Mortality:
- none
- Clinical signs:
- other: no symptoms
- Body weight:
- No significant differences regarding body weight growth in comparison to the air control group (see table)
- Gross pathology:
- nothing abnormal detected
- Interpretation of results:
- GHS criteria not met
Reference
Absolute body weight growth:
Mean body weight | before starting | after 7 days | after 14 days | |||
males | females | males | females | males | females | |
Group 1 | ||||||
Body weight in g | 185 | 178 | 219 | 190 | 258 | 206 |
No. of animals | 10 | 10 | 10 | 10 | 10 | 10 |
Control | ||||||
Body weight in g | 178 | 180 | 219 | 190 | 254 | 210 |
No. of animals | 10 | 10 | 10 | 10 | 10 | 10 |
Relative body weight growth:
Mean body weight | before starting | after 7 days | after 14 days | |||
males | females | males | females | males | females | |
Group 1 | ||||||
Body weight in g | 0 | 0 | 34 | 12 | 73 | 28 |
No. of animals | 10 | 10 | 10 | 10 | 10 | 10 |
Control | ||||||
Body weight in g | 0 | 0 | 41 | 10 | 76 | 30 |
No. of animals | 10 | 10 | 10 | 10 | 10 | 10 |
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed
- Dose descriptor:
- LC50
- Value:
- 6 300 mg/m³ air
- Physical form:
- inhalation: vapour
- Quality of whole database:
- study similar to OECD 403
Acute toxicity: via dermal route
Link to relevant study records
- Endpoint:
- acute toxicity: dermal
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- data from handbook or collection of data
- Qualifier:
- no guideline available
- Principles of method if other than guideline:
- In this study a rabbit received repeated exposures upon the abdomen to a 1% solution.
- GLP compliance:
- no
- Test type:
- standard acute method
- Limit test:
- no
- Species:
- rabbit
- Strain:
- not specified
- Sex:
- not specified
- Details on test animals or test system and environmental conditions:
- no data
- Type of coverage:
- not specified
- Vehicle:
- other: report states a 1% solution but doesn't identify the vehicle
- Details on dermal exposure:
- A rabbit received repeated exposures upon the abdomen to a 1% solution.
- Duration of exposure:
- no data
- Doses:
- 1% solution
- No. of animals per sex per dose:
- no data
- Control animals:
- no
- Dose descriptor:
- LD50
- Remarks on result:
- not determinable because of methodological limitations
- Interpretation of results:
- study cannot be used for classification
- Endpoint:
- acute toxicity: dermal
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Qualifier:
- no guideline available
- Principles of method if other than guideline:
- Range finding tests
- GLP compliance:
- no
- Test type:
- standard acute method
- Limit test:
- no
- Species:
- rabbit
- Strain:
- New Zealand White
- Sex:
- male
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: no data
- Age at study initiation: 3 to 5 months of age
- Weight at study initiation: averaging 2.5 kg
- Housing: immobilized in a hood to prevent inhalation of vapor during the 24-hour skin contact period
- Diet: ad libitum, Rockland rabbit ration
- Water (e.g. ad libitum): no data
- Acclimation period: no data - Type of coverage:
- occlusive
- Vehicle:
- unchanged (no vehicle)
- Details on dermal exposure:
- Male rabbits were immobilized in a hood to prevent inhalation of vapor during the 24-hour skin contact period. Thereafter, the polyethylene sheeting used to retain the dose in contact with the clipped skin of the trunk was removed and the animals were caged for the remainder of the 14-day observation period.
- Duration of exposure:
- 24 hour
- Doses:
- 1.25 or 2.5 mL/kg bw
- No. of animals per sex per dose:
- 4/dose
- Control animals:
- no
- Statistics:
- The moving average method of calculating the LD50 was used.
- Key result
- Sex:
- male
- Dose descriptor:
- LD50
- Effect level:
- 1.77 mL/kg bw
- Remarks on result:
- other: ca. 1469 mg/kg bw (density 0.03 mg/cm3)
- Mortality:
- 3/4 died at 2.5 mL /kg and 1/4 died at 1.25 mL/kg
- Clinical signs:
- other: The covered applications caused marked erythema and necrosis of the skin which healed with scab formation.
- Gross pathology:
- Lungs of victims sometimes had petechial hemorrhages, livers were pale or mottled, kidneys pale as were also the stomachs.
- Interpretation of results:
- Category 4 based on GHS criteria
- Endpoint:
- acute toxicity: dermal
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- data from handbook or collection of data
- Principles of method if other than guideline:
- Draize test
- GLP compliance:
- no
- Species:
- rabbit
- Strain:
- New Zealand White
- Sex:
- male
- Type of coverage:
- occlusive
- Details on dermal exposure:
- Observation period: 14 d
- Duration of exposure:
- 24 h
- No. of animals per sex per dose:
- 4
- Control animals:
- not specified
- Statistics:
- no data
- Sex:
- male
- Dose descriptor:
- LD50
- Effect level:
- > 1 500 - < 2 950 mg/kg bw
- Interpretation of results:
- Category 4 based on GHS criteria
Referenceopen allclose all
Butylene Oxide does not present a problem from skin absorption under ordinary handling conditions. However, prolonged exposure to relatively large areas of skin may result in the absorption of toxic amounts.
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed
- Dose descriptor:
- LD50
- Value:
- ca. 1 469 mg/kg bw
- Quality of whole database:
- WoE approach
Additional information
Acute oral
In the key study similar to OECD 401, an approximative oral LD50 value of about 913 mg/kg bw for male and female rats was reported. The substance was given via gavage as an emulsion in 0.5% aqueous CMC solution. Slight apathy, partially staggering, dyspnoea, diarrheic feces, exsiccosis, abdominal and lateral position were recorded (BASF SE, 1975).
In a supporting study, the substance was given orally (gavage) as a 10% solution in corn oil. Female rats were given doses of 1000 or 2000 mg/kg bw. No animal died in the low dose group; all animals died in the high dose group. Animals given 1 g/kg appeared normal during and after feeding and during a 2-week observation period. The LD50 was found to be > 1000- < 2000 mg/kg bw for female rats (Dow, 1965).
In another study the unchanged substance was tested. Male rats were dosed with the substance at levels differing by a factor of 2 in a geometric series. All animals died at 2 mL/kg and one animal died at 1 mL/kg. Clinical signs were not reported. The LD50 was found to be 1.3 mL/kg bw for male rats (Dow, 1958).
In a further study, the substance given in oral (gavage) doses of 0.63, 1 and 1.58 g/kg (10% in corn oil) resulted in an LD50 value for rats of > 2 and < 1.58 mg/kg bw. No mortalities were seen at 0.63 g/kg; all animals died at 1.58 g/kg; clinical signs were not reported (Dow, 1953).
Acute inhalation
In the key study similar to OECD TG 403, rats inhaled the test material in a concentration of 6.3 mg/L as a vapour for 4 hours. No mortalities and no symptoms were observed. Thus, the LC50 was greater than 6.3 mg/L for 4 hours (BASF SE, 1978).
In a supporting study, rats were exposed to an atmosphere saturated with the test substance (calculated around 660 mg/l or 200.000 ppm). Two rats died after 3-min exposure, all rats died at 10-min exposure. Clinical signs were irritation of the mucosa, dyspnoea and narcosis. Necropsy showed acute dilatation of the heart, congestive hyperemia and slight edema of the lung (BASF SE, 1975).
In a further study it was reported that the test substance has a very high vapour exposure. Rats survived a 6-minute exposure to saturated atmospheres at room temperature but failed to survive a 12-min exposure (Dow, 1965).
In another study (Dow, 1958), 8000 or 4000 ppm of the concentrated test substance vapour was tested up to 4 hours. The concentration of 8000 ppm (around 24 mg/l) was lethal for 6/6 rats within 4 hours; 1/6 rat died in the 4000 ppm (around 12 mg/l) concentration group.
In an older study (Dow, 1953) it was stated that butylene oxide presents a serious acute vapour inhalation hazard. Vapours in confined spaces may be dangerous even for single short exposure.
Acute dermal
For the endpoint acute dermal toxicity a WoE approach was applied.
An acute dermal LD50 value of 1.77 mL/kg bw (ca. 1469 mg/kg bw) was found for male rabbits. Unchanged 2-ethyloxirane was tested for 24 hours in doses of 1.25 or 2.5 mL/kg under occlusive conditions. The covered applications caused marked erythema of the skin which healed with scab formation. 3 of 4 rabbits died in the 2.5 mL/kg dose group and 1 of 4 rabbits died at the 1.25 mL/kg dose group (Dow, 1958).
The 1% solution of the test substance does not present a problem from skin absorption for rabbits under ordinary handling conditions. Prolonged exposure to relatively large areas of the skin may result in the absorption of toxic amounts. Further details are not given (Dow, 1953).
Smyth et al. (1962) found a dermal LD50 value of > 1500 - < 2950 mg/kg for male rabbits (24-hour occlusive). Further details are not given.
Justification for classification or non-classification
Classification, Labelling, and Packaging Regulation (EC) No 1272/2008
The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. Based on available data the test item is classified for acute oral, dermal and inhalation toxicity Cat.4 (H302, H312, H332) according to Regulation (EC) No 1272/2008 (CLP). The substance is harmonized classified for acute oral, dermal and inhalation toxicity Cat.4 (H302, H312, H332) according to Annex VI of Regulation (EC) No 1272/2008.
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