Registration Dossier
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: 203-815-1 | CAS number: 110-91-8
- 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
The LD50/LC50 values derived from the key-studies were: LD50 (oral, rat) 1900 mg/kg bw, LD50 (dermal, rabbit) 500 mg/kg bw, LC50 (rat) 8 g/m³. Based on these results, Morpholine is considered to be harmful following acute oral, dermal or inhalation exposure.
Key value for chemical safety assessment
Acute toxicity: via oral route
Endpoint conclusion
- Dose descriptor:
- LD50
- Value:
- 1 900 mg/kg bw
Acute toxicity: via inhalation route
Endpoint conclusion
- Dose descriptor:
- LC50
- Value:
- 8 000 mg/m³
Acute toxicity: via dermal route
Endpoint conclusion
- Dose descriptor:
- LD50
- Value:
- 500 mg/kg bw
Additional information
Acute toxicity: oral
The acute oral toxicity of Morpholine in the rat was examined in several toxicity studies. In general, oral administration of Morpholine to rats resulted in LD50 values within the range of 1000 to 2000 mg/kg bw (BASF AG, 1969; Shea, 1939; Smyth et al., 1954; Börzsönyi et al., 1981; Huntsman, 1981). Gastrointestinal and nasal haemorrhage were reported as clinical findings following oral Morpholine administration. When Morpholine was administered to 7 male rats at a neutral pH, no deaths occurred at 1000 mg/kg bw (Börzsönyi et al., 1981). In a supporting study on guinea-pigs (Shea, 1939) a lower LD50 of 900 mg/kg bw was observed.
The Huntsman study (1981) indicating LD50=1680 mg/kg bw ) is the key-study here. The BASF study from 1967, where a LD50 of ca.1900 mg/kg bw was derived, has been identified as a second key-study. These studies represent the most reliable study. A reliable source of test material was used and the test was done according to a well described BASF method which was in compliance with the principles of OECD Guideline 401. The same holds true for the Huntsman study.
Acute toxicity: dermal
In the key study on acute dermal toxicity (Smyth et al., 1954), necrosis on the clipped skin of albino rabbits was noted within 24 hours of application of undiluted Morpholine. Mortality observed within 14 days after dermal exposure to Morpholine resulted in an LD50 of 0.5 mL/kg bw. Due to the given specific density of Morpholine (1.0 g/cm³) a LD50 of 500 mg/kg bw was derived. In a supporting study (Shea, 1939), the single dermal exposure of rabbits to undiluted, unneutralized Morpholine resulted in irreversible skin injuries and death of some animals.
Acute toxicity: inhalation
Exposure to Morpholine at vapour saturation concentrations resulted in 100% lethality after 5.5 h (BASF AG, 1967). Irritating and corrosive properties were noted. In studies using lower Morpholine concentrations, Lam & Van Stee (1978) obtained LC50 values of 8.2 and 7.8 mg/L for male and female rats, respectively (exposure period was not specified; Fed. Proc., 37: 679, abstract no. 2459: A re-evaluation of the toxicity of morpholine). Other authors reported no deaths at a three times higher dose level (24 mg/L) after an exposure period of 4 hours (ILO, 1972). 9/10 rats died after a single exposure to 18.1 mg/L for 6 hours (Huntsman, 1981). With regard to other species, reported LC50 values for mice are consistently in the range of ca. 5 - 7 mg/L (Lam and Van Stee, 1978). Based on these findings and using a conservative approach (here: reflecting the results of Lam & Van Stee, 1978), a LC50 value of ca. 8.0 mg/L for rat is postulated and used for further calculations.
Justification for classification or non-classification
Classification, Labeling, and Packaging Regulation (EC) No 1272/2008
Based on the results for acute oral (LD50 rat ca. 1900 mg/kg bw), acute dermal (LD50 rabbit 500 mg/kg bw) and inhalation toxicity (LC50 ca. rat 8 mg/L) morpholine is classified as follows: acute toxicity: cat. 4, H302, harmful if swallowed, cat. 3, H311, toxic in contact with skin, and cat. 3, H331, toxic if inhaled (according to Regulation 1272/2008/EC).
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.

Route: .live1