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Diss Factsheets
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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
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Endpoint summary
Administrative data
Description of key information
The substance Paracetamol exhibits acute toxicity effect by the oral route in category IV,whereas it is non toxic by the inhalative route.
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:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Data from publication
- Qualifier:
- according to guideline
- Guideline:
- other:
- Principles of method if other than guideline:
- The acute oral toxicity and analgesic potency, in mice, of Paracetamol have been determined.
- GLP compliance:
- not specified
- Test type:
- standard acute method
- Limit test:
- no
- Specific details on test material used for the study:
- SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material:No data
- Expiration date of the lot/batch:No data
- Purity test date:No data
RADIOLABELLING INFORMATION (Not applicable)
- Radiochemical purity: N/A
- Specific activity:N/A
- Locations of the label:N/A
- Expiration date of radiochemical substance:N/A
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:No data
- Stability under test conditions:No data
- Solubility and stability of the test substance in the solvent/vehicle:No data
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium:No data
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing:The compounds were reduced to fine powder, suspended in 1% methylcellulose mucilage, and the mixture was homogenized.
- Preliminary purification step (if any):No data
- Final dilution of a dissolved solid, stock liquid or gel:No data
- Final preparation of a solid:No data - Species:
- mouse
- Strain:
- other: QS strain
- Sex:
- female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Weight at study initiation:18-22 g - Route of administration:
- oral: gavage
- Vehicle:
- other: 1% methylcellulose mucilage, and the mixture was homogenized
- Details on oral exposure:
- MAXIMUM DOSE VOLUME APPLIED: volume of 0.5 ml/20 g
- No. of animals per sex per dose:
- 20 female mice
- Control animals:
- not specified
- Details on study design:
- - Duration of observation period following administration: Deaths were counted after 48 hr.
- Frequency of observations and weighing: No data
- Necropsy of survivors performed: No data
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: No data - Statistics:
- LD50 and confidence limits were calculated by the method of Litchfield and Wilcoxon.
- Sex:
- female
- Dose descriptor:
- LD50
- Effect level:
- 338 mg/kg bw
- Based on:
- test mat.
- 95% CL:
- 306 - 373
- Mortality:
- Not reported
- Clinical signs:
- other: Not reported
- Gross pathology:
- Not reported
- Other findings:
- - Other observations: Analgesic Activity : 4-Hydroxyacetanilide (paracetamol) was only weakly active as an analgesic, which was somewhat surprising in view of its widespread clinical use.The analgestic toxicity was found to be 22% observed with the help of hotplate test.
- Interpretation of results:
- Toxicity Category IV
- Remarks:
- Migrated information Criteria used for interpretation of results: EU
- Conclusions:
- The acute oral median lethal dose (LD50) of Paracetamol,when administered to mouse was found to be 338 mg/kg body weight. Thus by considering the CLP criteria for acute toxicity rating for the chemicals, it infers that Paracetamol exhibits acute toxicity by the oral route in “Category 4”.
- Executive summary:
The acute oral median lethal dose (LD50) of Paracetamol,when administered to mouse was found to be 338 mg/kg body weight. Thus by considering the CLP criteria for acute toxicity rating for the chemicals, it infers that Paracetamol exhibits acute toxicity by the oral route in “Category 4”.
Reference
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed
- Dose descriptor:
- LD50
- Value:
- 338 mg/kg bw
- Quality of whole database:
- The data is K2 level as the data has been obtained from the experimental study from the 'Journal of Toxicology and Applied Pharmacology.’.
Acute toxicity: via inhalation route
Link to relevant study records
- Endpoint:
- acute toxicity: inhalation
- Data waiving:
- other justification
- Justification for data waiving:
- other:
Reference
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed
- Quality of whole database:
- .
Acute toxicity: via dermal route
Link to relevant study records
- Endpoint:
- acute toxicity: dermal
- Data waiving:
- study scientifically not necessary / other information available
- Justification for data waiving:
- other:
Reference
Endpoint conclusion
- Endpoint conclusion:
- no adverse effect observed
Additional information
Acute toxicity: oral No. of studies were reviewed for acute oral toxicity from reliable sources having Klimisch rating 2 .
Based on the study conducted by G.A. Starmera et.al (Toxicology and Applied Pharmacology. Vol. 19, Pg. 20, 1971.) And other reliable sources, The acute oral median lethal dose (LD50) of Paracetamol in mouse was found to be 338 mg/kg of body weight.
Similarly in the study conducted on mice byAnthony et.al (Biorganic & Medicinal Chemistry 15,2206,2007) reported the LD 50 to be 559mg/kgbw.
Another publication by Michael Helliwel et.al ( Hum Exp Toxicol January 1981 vol. 1 no. 1 25-30) found the LD 50 to be714mg/kg.data fromAmerican Journal of Emergency Medicine and SAX handbook predicted the LDL0 and LD50 to be 650mg/kg and 367mg/kg ,Clearly indicating the toxicity of substance classifying it under oral acute category IV.
Acute toxicity: inhalation
No. of studies were reviewed for acute inhalation toxicity from reliable sources having Klimisch rating 2.
The summary of the results are presented below
Sr.No |
Endpoint |
Effect values |
Species |
Exposure Duration |
CAS No. |
Sources |
1 |
LC50 |
49.8 mg/L |
Rat |
4 h |
103-90-2 |
Predicted data from QSAR |
2 |
LC50 |
33900 mg/m³ air |
Mouse |
- |
Read Across 62-44-2 |
Experimental data from Gigiena i Sanitariya. |
By applying weight of evidence approach to the target substance Paracetamol and the read across substance phenacetin,the endpoint value was found to vary between LC50 = 49.8 mg/L to 33900 mg/m³ air.Thus it is concluded that Paracetamol does not exhibits acute toxicity by the inhalative route within the mentioned dose level.
Acute toxicity: dermal
Acute toxicity testing by the dermal route was considered for waiver due to the following exposure considerations; the physicochemical and toxicological properties of paracetamol do not suggest potential for a significant rate of absorption through the skin. In addition, for paracetamol, the most likely route of exposure is oral considering its use. Considering that paracetamol is a solid, the other potential route of exposure could be inhalation, given the exposure to the fine particles. Thus having satisfied all the conditions as mentioned in column 2 of Annex VIII, this end point was considered for waiver.
Justification for selection of acute toxicity – oral endpoint
The acute oral median lethal dose (LD50) of Paracetamol in mouse was found to be 338 mg/kg of body weight. Acute toxicity of Paracetamol to mouse by oral route indicates that Paracetamol exhibits acute toxicity by the oral route in the category IV.
Justification for selection of acute toxicity – inhalation endpoint
For paracetamol, acute toxicity testing by the inhalation route was considered for waiver given that the substance particle size distribution indicates that the majority particle size is 500 micro meter. Thus, exposure by inhalation route is also unlikely for paracetamol given the comparatively larger size of the particulates.
Justification for selection of acute toxicity – dermal endpoint
Acute toxicity testing by the dermal route was considered for waiver due to the following exposure considerations; the physicochemical and toxicological properties of paracetamol do not suggest potential for a significant rate of absorption through the skin. In addition, for paracetamol, the most likely route of exposure is oral considering its use. Considering that paracetamol is a solid, the other potential route of exposure could be inhalation, given the exposure to the fine particles. Thus having satisfied all the conditions as mentioned in column 2 of Annex VIII, this end point was considered for waiver.
Justification for classification or non-classification
Based upon the study results and available information, the substance Paracetamol exhibits acute toxicity effect by the oral route in category IV,whereas it is non toxic by the inhalative route.
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.
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