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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 203-533-9 | CAS number: 107-93-7
- 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
Link to relevant study record(s)
Description of key information
Based on the available physicochemical and toxicological data, Crotonic acid is considered to be bioavailable after oral exposure. Absorption after dermal exposure is limited and exposure via inhalation is not relevant due to the low vapour pressure and high particle size. Following uptake the compound is likely to be readily distributed throughout the body. The formation of reactive metabolites is considered unlikely. Excretion of Crotonic acid occurs most likely via urine.
Key value for chemical safety assessment
- Bioaccumulation potential:
- no bioaccumulation potential
- Absorption rate - oral (%):
- 100
- Absorption rate - dermal (%):
- 25
- Absorption rate - inhalation (%):
- 100
Additional information
In line with chapter R.7 c (ECHA, 2012) the main toxicokinetic properties of Crotonic acid (CAS-No. 107-93-7) are assessed on the basis of its physico-chemical properties and with special regard to the results of the standard toxicity studies performed with this substance. Specific toxicokinetics or dermal absorption studies are not available for the substance.
1. Relevant physico-chemical properties of Crotonic acid
Molecular weight: 86.09 g/mol
Physical state: crystal (white)
logPow: 0.85
Water solubility: 94 g/L
pKa: 4.69
Vapour pressure: 0.25 hPa (20°C)/ 25 Pa (20°C)
Particle size: >125 µm
2. Absorption
Oral Absorption
Based on its low molecular weight of 86.09 g/mol Crotonic acid is likely to be absorbed in the GI tract since small molecules with a molecular weight below 500 g/mol do favour absorption. This assumption is supported by the results of the acute oral toxicity study (Hoechst AG (a), 1967) indicating signs of systemic toxicity like imbalance and narcosis prior to death. It is generally thought that ionized substances do not readily diffuse across biological membranes. On this basis, absorption of acids are favoured at pHs below their pKa values. Since the pKa of Crotonic acid is 4.69 an absorption in the stomach (pH stomach < 4.69) seems to be most relevant. The log Pow value of 0.85 leads to the conclusion that absorption of the test substance occurs generally by passive diffusion which requires a moderate log Pow value (between -1 and 4). However, due to the good water solubility absorption by passive diffusion may be limited by the rate at which the substance partitions out of the gastrointestinal fluid.
Absorption after inhalation
Substances with a vapour pressure of less than 0.5 KPa (500 Pa) have a low volatility. Since the vapour pressure of Crotonic acid is 25 Pa the availability for inhalation as a vapour is low. In addition, the potential to be inhaled by humans is given if the particles exhibit an aerodynamic diameter below 100 µm. Since Crotonic acid does not contain any particles smaller than 125 µm an exposure to inhalable particles of the compound is not expected. If an inhalable/respirable dust were generated and based on the physico-chemical properties, a precipitation on the mucous membranes of the upper airways followed by mucociliary cleansing and transport into the stomach seems more likely than an absorption in the alveolar region of the respiratory tract. The results obtained in the acute inhalation toxicity study (Hoechst AG (b), 1967) are in agreement with this assumption. Within this study rats were exposed to the vapoured test item in an exposure chamber (whole body exposure). The concentration of the test item is unknown as the evaporated test item recrystallised partly before the vapour reached the inhalation chamber. Nevertheless, no mortality and no systemic toxicity were observed.
Dermal absorption
With respect to the low molecular weight (< 100 g/mol) and the log Pow between 1 and 4 a dermal uptake of Crotonic acid might be expected. However, a substance must be non-ionised at the skin's pH to partition into the skin and also sufficiently soluble in water to partition from the stratum corneum into the epidermis. Based on the pKa of 4.69 dermal absorption of Crotonic acid is anticipated to be low to moderate. This is further supported by the results of an acute dermal toxicity study (Toxi-Coop Zrt. (b), 2012) performed on rats. During the study no mortality and no systemic toxic effects were observed for the highest dose of 2000 mg/kg bw.
3. Distribution/Metabolism
In view of the clinical signs observed in the acute oral toxicity study (Hoechst AG (a), 1967) with Crotonic acid, its low molecular weight, the water solubilty of 94 g/L and the log Pow of 0.85 a wide distribution and no accumulation of Crotonic acid in the body can be expected.
Generally, metabolism will render a xenobiotic molecule more polar and harmless, leading to fast and quantitative excretion. For Crotonic acid, no conversion into a metabolite that was more cytotoxic or more genotoxic than the parent substance was noted when comparing in vitro test results with metabolic activation to in vitro test results without metobolic activation system (genetic toxicity tests). Thus, the formation of reactive metabolites is unlikely.
4. Excretion
Based on its log Pow (0.86) the test substance has no potential to bioaccumulate in the human body. The low molecular weight (below 300 g/mol), the good water solubility and the ionization of the molecule at pH of urine (pH urine > pKa Crotonic acid) indicated urinary excretion as most relevant route of excretion for Crotonic acid.
5. Generic absorption rates
Based on the above information and due to the fact that there are no specific toxicokinetic data available the generic values of 100 % for oral absorption and inhalation absorption of respirable particles as well as 25 % for dermal absorption were derived.
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.