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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 203-157-5 | CAS number: 103-90-2
- 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
Additional information
Appearance/physical state/colour
On the basis of experimental results Paracetamol was found to be a White powder organic solid.
Melting point/freezing point
The melting point determination of Paracetamol (CAS No.103-90-2) was done following OECD Guideline 102 and according to the Capillary/metal block method. The test was conducted in replicates and mean melting point range was found to be 165.6 °C - 168°C at 980.4hPa.
Boiling point
The boiling point determination of Paracetamol (CAS No. 103-90-2 ) was done following OECD Guideline 103 and according to the method of Siwoloboff. The test was conducted in replicates and mean boiling point was found to be greater than 250 °C at 980.1 hPa.
Density
The density of test item Paracetamol (CAS No. 103-90-2 )was determined following OECD Guideline 109 and according to the method Adapted from ASTM D854-02 using glass pyknometer .The mean density of the test item was found to be 1.214 g/cm3 at 20 °C and 977.1.hPa.
Particle size distribution (Granulometry)
The particle size distribution of test itemParacetamol (CAS No. 103-90-2)was determined by granulometric analysis with rotap sieve shaker. The cumulative percentages of test item obtained for each sieve are as follows:
Sieve sizes(in microns) |
Percentage distribution (%) of test item |
150 microns |
23.52% |
106 microns |
36.02 % |
75 microns |
34.44% |
53 microns |
3.88% |
25 microns |
0.14% |
10 microns |
------- |
Vapour pressure
The vapour pressure of paracetamol was found to be 0.008385954 Pa at 25 degC.
Partition coefficient
The experimental value of octanol water partition co-efficient (log Pow) of paracetamol is 0.46 at temperature 25 degC.This value indicates that paracetamol is hydrophilic in nature.
Water solubility
The water solubility determination of test item Paracetamol (CAS No. 103-90-2) was done gravimetrically as per the shake flask method using membrane filtration followed by air drying. The water solubility was found to be 19 g/L at 28 deg.C.
Solubility in organic solvents / fat solubility
Gravimetric method was used to determine the solubility of the substance in organic solvent.The experimental value of solubility of paracetamol in ethanol at 26 degC was found to be 3000 mg/L indicating that this substance is soluble in ethanol.Using the Soxhlet/Solvent extraction method the solubility of the substance in Petroleum ether is observed to be 40 mg/L at 26 degC indicating that the substance is slightly soluble in Petroleum ether.The solubility value of paracetamol in ethanol at 20 degC is equivalent to a value of 2307.69 mg/L.
Surface tension
Paracetamol is a solid chemical. In order to calculate surface tension it shall have to be dissolved either in water or an organic solvent. In this case, there is every likelyhood that the surface tension that shall be calculated of the solution of paracetamol might actually erroneously reflect the measurement of surface tension of the solvent (either water or organic solvent). Hence this end point was considered for waiver considering the technical difficulty in surface tension measurement of solid paracetamol.
Flash point
The flash point determination of Paracetamol (CAS No. 103-90-2) was done following closed cup method using Pensky-Martens flash point apparatus. The test was conducted in replicates and mean flash point was found to be 184.6 °C at 979.9 hPa.
Auto flammability
Paracetamol did not catch fire on being exposed to air at room temperature of 26 degC and atmospheric pressure of 966 hPa. This indicates that paracetamol is not auto-flammable.
Flammability
From the experimental values of flammability, paracetamol ignited when the flame of bunsen burner having temperature of 950 degC was brought in contact with it. Thus it can be concluded that paracetamol is flammable only at high temperature of about 950 degC. However since such high temperatures are not found under normal circumstances of transportation and use, paracetamol was considered non-flammable for chemical safety assessment.
Explosiveness
According to theoretical considerations based on chemical structure, paracetamol does not possess explosive properties. The reason for this is there are no chemical groups associated with explosive properties in paracetamol. Thus, as per column 2 of Annex VII this end point was considered for waiver.
Oxidising properties
Paracetamol was found to have mild oxidising property since 284.4 ml of KMnO4 was required for getting the end point of the redox titration for 100 g of paracetamol.This oxidation potential was not considered strong enough for classifying the chemical as an oxidising solid.Thus, the chemical is considered as non-oxidising for the purpose of chemical safety report and classification.
Stability in organic solvents and identity of relevant degradation products
Paracetamol was found to be stable in organic solvent dichloro methane and no degradation products were formed after 24 hours as evident from the GC-MS chromatogram obtained at 0 hours and that obtained after 24 hours.
pH
The pH determination of test item Paracetamol (CAS No. 103-90-2) was done following OECD guideline 122. pH of 1% w/v aqueous solution was measured with the help of pH meter and it was observed to be 5.82 at 30°C
Dissociation constant
The experimental pKa value for paracetamol was found to be 0.000000523 at 26 degC indicating that it has dissociation properties.This value when converted at 20 deg C is equivalent to 0.000000402.
Viscosity
This end point was considered for waiver since viscosity is an inherent property of a liquid that offers resistance to its flow and paracetamol is a solid substance and hence this testing was considered scientifically unjustified for paracetamol.
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.