Paracetamol is a member of the class of phenols that is 4-aminophenol in which one of the hydrogens attached to the amino group has been replaced by an acetyl group.
How much products actually contain
No product states its amount yet.
Of the products containing it, 0 list it before the 1% line and 1 after it (usually 1% or less).
Products using this ingredient
1 of 1 confirmed · likeliest to carry enough first
Definition
Paracetamol is a member of the class of phenols that is 4-aminophenol in which one of the hydrogens attached to the amino group has been replaced by an acetyl group. It has a role as a ferroptosis inducer, a geroprotector, a non-steroidal anti-inflammatory drug, a non-narcotic analgesic, an antipyretic, a xenobiotic, a cyclooxygenase 2 inhibitor, a cyclooxygenase 1 inhibitor, a hepatotoxic agent, a cyclooxygenase 3 inhibitor, an environmental contaminant and a human blood serum metabolite. It is a member of acetamides and a member of phenols. It is functionally related to a 4-aminophenol.
Source: PubChem
US FDA substance register · UNII 362O9ITL9D · registered name Acetaminophen · single chemical substance
Cosmetic roles
Safety & regulatory references
Not classified under Korea’s toxic-substance GHS list · existing chemical substance
More data — names, identifiers, properties, test records, literature
Names & identifiers
- CAS No.chemical registry number
- 103-90-2
- EC No.EU chemical inventory number
- 203-157-5
- DTXSIDUS EPA chemical ID
- DTXSID2020006
- DTXCIDUS EPA compound ID
- DTXCID606
- IUPAC
- N-(4-Hydroxyphenyl)acetamide
- Molecular formula
- C8H9NO2
- Molecular weight
- 151.165 g/mol
Measured properties
- Appearance
- 4-hydroxyacetanilide is an odorless white crystalline solid. Bitter taste. pH (saturated aqueous solution) about 6. (NTP, 1992) · Colorless solid, [ICSC] Odorless white solid, [CAMEO] White powder, [Sigma-Aldrich MSDS]
- Odour
- Odorless · odourless
- Boiling point
- >500 · >500 °C
- Melting point
- 336 to 342 °F (NTP, 1992) · 168-172
- Solubility
- 1 to 5 mg/mL at 72 °F (NTP, 1992) · very slightly soluble in cold water but greater solubility in hot water
- Density
- 1.293 at 70 °F (NTP, 1992) - Denser than water, will sink · 1.293 g/cu cm at 21 °C
- Stability
- Stable under recommended storage conditions.
- pH
- Saturated aqueous solution: 5.5-6.5 · 5.5~6.5
- Dissociation constant
- pKa = 9.38
- Colour
- colourless
- Melting/freezing point
- 169~170 ℃
- Initial boiling point and range
- &, gt, 500 ℃
- Flash point
- 177 ℃(o.c., @ 966 hPa)
- Flammability (solid, gas)
- combustible
- Upper/lower flammability or explosive limits
- 15 / - %
- Vapour pressure
- 0.0000629 ㎜Hg (@ 25 ℃)
- Water solubility
- 1.4 g/100㎖ (@ 20 ℃)
- Vapour density
- 5.2
- Relative density
- 1.293 (@ 21 ℃)
- n-Octanol/water partition coefficient (Kow)
- 0.49
- Auto-ignition temperature
- 540 ℃
- Molecular weight
- 151.17
Values measured on the substance itself. The KOSHA data are a reference for writing and reviewing safety data sheets, not a specification for a commercial raw material.
Source: PubChem · KOSHA safety data sheets (Korea)
What products actually use it for
What the 54 products reported to the US EPA with this ingredient use it for. Products outside cosmetics are included, so the top few rows are its main uses.
- Pharmaceutical (EPA)51
- Stabilizing agent1
- Monomers1
- Softener and conditioner1
Source: US EPA CompTox dashboard
Irritation and sensitisation studies
4 skin studies and 1 eye studies are on record.
The study conclusions largely agree (100%). These tests are on the raw material itself; irritation at the amount in a finished product is a different question.
See all 5 studies
- Moderate or Mild Irritation
skin irritation: in vivo · Screening · other guideline: according to - Classification not possible
Skin Irritation · Screening - SkinSens1
Skin Sensitization · QSAR Predicted - Classification not possible
Skin Sensitization · Screening - Classification not possible
Eye Irritation · Screening
Source: US EPA CompTox dashboard
Related literature
- Perioperative anaphylaxis attributed to acetaminophen following intravenous acetaminophen administration: a case report · 2025
- Permeation Characteristics of Acetaminophen Using Franz Diffusion Cells · 2022
- Toxic epidermal necrolysis caused by acetaminophen featuring almost 100% skin detachment: Acetaminophen is associated with a risk of severe cutaneous adverse reactions · 2016
- A Case of Toxic Epidermal Necrolysis Secondary to Acetaminophen in a Child. · 2016
- Acetaminophen (paracetamol)-induced anaphylactic shock. · 2002
Linked databases 21
- Australian Industrial Chemicals Inventory (AICIS)
- ChEBI
- ChEMBL
- China inventory of existing ingredients (IECIC)
- EU CosIng ingredient list 2
- IARC carcinogen classification
- Korea Cosmetic Association ingredient dictionary
- Korea toxic substances GHS register (NIER)
- KOSHA safety data sheets (Korea)
- MFDS (Korea) cosmetic ingredient register 2
- NIST Chemistry WebBook
- PubChem 2
- Tlooto literature search 2 3 4 5
- UniChem cross-reference IDs
- US EPA CompTox dashboard 2
- US EPA DSSTox chemical database
- US FDA substance registration (GSRS)
- US FDA Unique Ingredient Identifier (UNII)
- US National Toxicology Program reports
- Wikidata
- Wikipedia · Korean · English · Japanese · Chinese