NOAEL Data Cosmetic Ingredient

2-Hydroxy-1,4-naphthoquinone

Also known as: 4-08-00-02360, BRN 1565260, EINECS 201-496-3, UNII-TLH4A6LV1W, Henna

CAS 83-72-7

2-Hydroxy-1,4-naphthoquinone (CAS 83-72-7) is a chemical substance. Key regulatory status: 5 regulatory/inventory lists, cosmetic ingredient cross-reference; source data from EPA ToxValDB, EPA CPDat, AICIS.

View cosmetic safety profile for Lawsone →

SOURCE NOAEL studies

NOAEL studies

SOURCE Chemical inventory jurisdictions

Regulatory lists

SOURCE EU CLP Annex VI

GHS signal

Not classified

Chemical Identity

CAS, identifiers, formula, and alternate names for the matched substance record.

SOURCE DSSTox identifiers 10 fields

Name

2-Hydroxy-1,4-naphthoquinone

CAS Number

83-72-7

Molecular Formula

C10H6O3

InChI Key

CSFWPUWCSPOLJW-UHFFFAOYSA-N

Monoisotopic Mass

174.031694

Synonyms

4-08-00-02360BRN 1565260EINECS 201-496-3UNII-TLH4A6LV1WHenna

Functional Uses

Industrial and product-use categories associated with this substance.

SOURCE EPA CPDat 1 records

Dye

Regulatory Lists

Inventory, screening, and regulatory list matches from public chemical databases.

SOURCE EPA CPDat 5 records

List	Keyword	Source
Europe; Personal care - hair coloring	Danish Environmental Protection Agency	Danish EPA
Europe; Personal care - hair coloring	Danish Environmental Protection Agency	Danish EPA
Europe; Personal care - hair coloring	Danish Environmental Protection Agency	Danish EPA
Europe; Personal care - hair coloring	Danish Environmental Protection Agency	Danish EPA
Canada; pharmaceutical	DrugBank	DrugBank

NOAEL Studies

Toxicology endpoints rendered from public NOAEL study rows.

SOURCE NOAEL studies Showing 20 of 20 studies

Value	Unit	Endpoint	Route	Species	Source
0.5	%	-	oral	rat	Regulatory source
2	mg/kg bw/day	-	oral	-	Regulatory source
7	mg/kg bw/day	-	-	-	Regulatory source
20	mg/kg bw/day	-	-	-	Regulatory source
TLH4A6LV1W	UNII	FDA UNII substance identifier	-	-	openFDA substances
2	mg/kg bw/day	LOAEL	oral	rat	COSMOS DB
=0.5	%	NOAEL	oral	rat	SCCNFP Opinion
=2	mg/kg bw/day	NOAEL	-	rabbit	SCCNFP Opinion
=2	mg/kg bw/day	NOAEL	oral	-	SCCNFP Opinion
=7	mg/kg bw/day	NOAEL	-	rabbit	SCCNFP Opinion
=20	mg/kg bw/day	NOAEL	-	-	SCCNFP Opinion
=20	mg/kg bw/day	NOAEL	-	human	SCCNFP Opinion
=300	mg/kg	NOAEL	dermal	rat	SCCNFP Opinion
2	mg/kg bw/day	dermal absorption	oral	rat	Regulatory source
7	mg/kg bw/day	dermal absorption	-	human	Regulatory source
20	mg/kg bw/day	dermal absorption	-	human	Regulatory source
300	mg/kg	dermal absorption	dermal	rat	Regulatory source
2	mg/kg bw/day	irritation	-	rabbit	Regulatory source
2	mg/kg bw/day	irritation	-	rat	Regulatory source
7	mg/kg bw/day	irritation	-	rabbit	Regulatory source

Showing 20 of 20 studies

Australian Status (AICIS)

Australian industrial chemicals inventory status and applicable conditions.

SOURCE AICIS inventory 1 records

Inventory Status

listed

Cosmetic Safety Profile

Same-CAS cosmetic ingredient record for cross-vertical context.

SOURCE CosIng / Ingredients DB

EU Status

prohibited

Max

Pharmaceutical Data

Same-CAS pharmaceutical records from drug and bioactivity sources.

SOURCE ChEMBL / DailyMed LAWSONE

ChEMBL Phase

Not listed

Adverse Events

Bioactivity

View full pharmaceutical profile →

Food Safety Data

Same-CAS food additive, ADI, and GRAS records where available.

SOURCE EFSA 1 records

1 food-safety record found.

View full food safety profile →

Frequently Asked Questions

What is the NOAEL for 2-Hydroxy-1,4-naphthoquinone?

2-Hydroxy-1,4-naphthoquinone has 20 NOAEL studies in the database. The lowest reported value is 0.5 % via oral in rat. Source: Regulatory source.

What regulatory lists include 2-Hydroxy-1,4-naphthoquinone?

2-Hydroxy-1,4-naphthoquinone appears on 2 regulatory/inventory lists including Europe; Personal care - hair coloring, Canada; pharmaceutical. Source: EPA CPDat.

Is 2-Hydroxy-1,4-naphthoquinone used in cosmetics?

Yes, 2-Hydroxy-1,4-naphthoquinone is also indexed as a cosmetic ingredient under the name Lawsone. View the full cosmetic safety profile on the ingredient page for detailed safety data, SCCS opinions, and regulatory status.

Where does the safety data for 2-Hydroxy-1,4-naphthoquinone come from?

Safety data is sourced from EPA ToxValDB, EPA CPDat, AICIS (Australian Industrial Chemicals Introduction Scheme), EPA DSSTox, CosIng / Ingredients DB, ChEMBL / DailyMed, EFSA / FDA GRAS. All data traces to primary regulatory sources and is updated from official government databases.

Is 2-Hydroxy-1,4-naphthoquinone used outside industrial chemicals?

2-Hydroxy-1,4-naphthoquinone also appears in cosmetics, pharmaceutical, food safety databases.