- beauty
- cleaning
- food
- pharma
5-Fluorouracil
CAS 51-21-8 · 100/100 · High conf.
Also registered as 9 other CAS numbers
2794-13-0 · 191047-64-0 · 191047-65-1 · 191115-88-5 · 635702-33-9 · 665011-29-0 · 1004-03-1 · 4921-97-5 · 79108-01-3
Concern score
100/100Critical concern based on regulatory listings.
High confidence
5-Fluorouracil in plain language
Also known as Fluorouracil · 5-FLUOROPYRIMIDIN-2,4(1H,3H)-DIONE · Fluorouracil (INN) · 5-FLUORURACIL · 5-Fluoropyrimidine-2,4(1H,3H)-dione · 5-fluoro-1H-pyrimidine-2,4-dione
Show all 44 names
Fluorouricil · Phthoruracil · Queroplex · 2,4(1H,3H)-Pyrimidinedione, 5-fluoro- · 2,4-Dihydroxy-5-fluoropyrimidine · 2,4-Dioxo-5-fluoropyrimidine · 5 fluorouracil · 5-FLUORO-URACIL · 5-FU · 5-Fluoracil · 5-Fluoracyl · 5-Fluoro-2,4(1H,3H)-pyrimidinedione · Adrucil · Arumel · Carac · Carzonal · Efudex · Efurix · Favlyxa · Fluoroplex · Fluoroblastin · Fluorouracil, 5- · Fluorouracilo · Fluracil · Fluracilum · Fluril · Fluro Uracil · Ftoruracil · Ro 2-9757 · RO-29757 · Tolak · Timazin · Ulup · Uracil, 5-fluoro- · fluorouracil (sara 302) · fluorouracil (sara iii) · Folfox component fluorouracil · Fluorouracilum
We don't have a plain-language description for 5-Fluorouracil yet.
- Critical concern: no hazard classifications on record. It is banned in EU cosmetics.
Why it's flagged
Fluorouracil (INN) is prohibited in cosmetic products under Annex II of the EU Cosmetics Regulation (EC) 1223/2009.
RestrictedEU EC — banned
The score describes this ingredient's chemical identity — its hazard profile from published classifications and regulatory status — not the safety of any product it appears in.
Regulation
Restrictions first, then routine listings from published regulatory sources.
- In marketed US drugs
- EU Annex II — prohibited
- EU prohibited in cosmetics
- Found in consumer products
- Beauty
- Cleaning
- Pharma
- Food
- View source →banned
EUEC
Annex II of EU Cosmetics Regulation (EC) 1223/2009: substances prohibited in cosmetic products.
EUCosIngActiveCosmetics Regulation annex II / ref 190.
- Cosmetics Regulation annex II / ref 190.Source →
USEPAcommercial use observedEPA CPDat observed this chemical in 10 composition records across product categories including Food and drug, Personal care.
- EPA CPDat observed this chemical in 10 composition records across product categories including Food and drug, Personal care.Source →
USFDAmarketed drug occurrenceFDA NDC lists this ingredient in 46 active drug products and 46 total products.
- FDA NDC lists this ingredient in 46 active drug products and 46 total products.Source →
USFDAlisted in openFDA substanceopenFDA substance registry classifies this ingredient as chemical.
- openFDA substance registry classifies this ingredient as chemical.Source →
Expert safety opinions
No expert opinion on file for 5-Fluorouracil. These are the independent scientific bodies that assess ingredients like this one; we show an opinion only when a record we hold cites it.
SCCS
EU Scientific Committee on Consumer Safety
No SCCS opinion on file.
CIR
Cosmetic Ingredient Review (US expert panel)
No CIR safety assessment on file.
JECFA
Joint FAO/WHO Expert Committee on Food Additives
No JECFA evaluation on file.
EFSA
European Food Safety Authority
No EFSA opinion on file.
Evidence & sources
No graded research studies for 5-Fluorouracil yet. This record is compiled from the published data sources below — registries and regulatory listings, not study findings.
Where this comes from
- Open →
CosIng
regulatory · updated 2026-09-23
- Open →
EU CosIng Cosmetics Regulation Annexes
regulatory · updated 2010-10-15
- Open →
EPA Chemical and Products Database
exposure · updated March 8, 2019
- Open →
EPA DSSTox Identifiers
chemistry · updated 2025-12-29
- Open →
FDA National Drug Code Directory
regulatory · updated 2027-12-31
- Open →
FDA GSRS UNII
registry · updated 2026-02-26
- Open →
openFDA Substance
registry · updated 2026-05-24
- Open →
PubChem Live Enrichment
chemistry · updated 2026-05-17
Suitability
Context-specific fit derived from published classifications and the current ingredient evidence profile.
Food use
Food-use source coverage is present in the current record.
The ingredient appears in food-oriented source coverage or allowed-use references, which makes food use easier to support than a context with no domain signal at all.
Fragrance avoidance
No fragrance-linked caution surfaced in the current profile.
This ingredient does not currently read as a fragrance-linked driver in the published evidence and hazard profile.
Where it has been recorded
How often FDA National Drug Code directory has listed 5-Fluorouracil in a product composition. These are source records, not Greenveil catalog products.
Source records
46