beauty
cleaning
food
industrial

Calcium hydroxide

CAS 1333-29-5 · 70/100 · High conf.

Also registered as 3 other CAS numbers

7719-01-9 · 1351974-67-8 · 1305-62-0

Concern score

70/100High concern based on regulatory listings.

High confidence

Calcium hydroxide in plain language

What it is: Also known as Hydrated lime · Lime water · Slaked lime · Calcium hydroxide (CA(OH)2) · Calcium dihydroxide · Lime hydrate
Show all 20 names
Biocalc · Ca(OH)2 · Calbreed · Calcicure · Calcium hydrate · E-526 · Hydroxid calcium · Ins NO.526 · calcii hydroxidum · calcium hydroxide vp:0 @ 68f · calcium hydroxide. vp: 0 @ 68. · lime · Calcarea caustica · Calcium hydroxide solution
What it does: Used in cosmetics as a pH buffer.
Buffering
Acidity regulator, firming agent
pH adjuster
Is it a concern?: High concern: no hazard classifications on record. It is restricted in EU cosmetics.

Why it's flagged

Calcium hydroxide is restricted in cosmetic products under Annex III of the EU Cosmetics Regulation (EC) 1223/2009.

RestrictedEU EC — restricted

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 III — restricted
EU restricted in cosmetics
Inactive ingredient in US drugs

Recorded in these product areas

Found in consumer products
Cleaning
Industrial

EUEC
Annex III of EU Cosmetics Regulation (EC) 1223/2009: substances which cosmetic products must not contain except subject to the restrictions laid down. Product types: (a) Hair straighteners containing two components: calcium hydroxide and a guanidine salt (b) pH ajuster for depilatories (c) Other uses (e.g. pH adjuster, processing aid) Maximum concentration: (a) 7% (as calcium hydroxide) Other conditions: (b) pH < 12.7 (c) pH < 11 Conditions of use and warnings: (a) Contains alkali Avoid contact with eyes Keep out of reach of children Can cause blindness (b) Contains alkali Keep out of reach of children Avoid contact with eyes
restricted
View source →

USFDAinactive ingredient database4 entries — 3 administration routes
- Route: ORAL; Dosage form: SUSPENSION; Potency: ADJ PHSource →
- Route: SUBCUTANEOUS; Dosage form: INJECTION; Potency: ADJ PHSource →
- Route: ORAL; Dosage form: CAPSULE, EXTENDED RELEASE; Maximum daily exposure: 14 mgSource →
- Route: INTRAVENOUS; Dosage form: INJECTION; Potency: 3.7 mgSource →
EUCosIngActive2 entries
- Restriction: III/15cSource →
- Cosmetics Regulation annex III / ref 15c.Source →
GLOBALJECFAEvaluatedJECFA evaluation record.
- JECFA evaluation record.Source →
GLOBALJECFANOT LIMITEDJECFA evaluation lists ADI NOT LIMITED. Functional class: acidity regulator, firming agent.
- JECFA evaluation lists ADI NOT LIMITED. Functional class: acidity regulator, firming agent.Source →
USEPAcommercial use observedEPA CPDat observed this chemical in 667 composition records across product categories including Construction and building materials, Furniture and furnishings, Raw materials. EPA CPDat classifies this chemical for functional uses including pH regulating agent, Flame retardant, aggregate.
- EPA CPDat observed this chemical in 667 composition records across product categories including Construction and building materials, Furniture and furnishings, Raw materials. EPA CPDat classifies this chemical for functional uses including pH regulating agent, Flame retardant, aggregate.Source →
USFDAlisted in openFDA substanceopenFDA substance registry classifies this ingredient as chemical.
- openFDA substance registry classifies this ingredient as chemical.Source →
USFDAmarketed drug occurrenceFDA NDC lists this ingredient in 13 active drug products and 13 total products.
- FDA NDC lists this ingredient in 13 active drug products and 13 total products.Source →

Expert safety opinions

Independent scientific assessments cited by the records we hold, with the year and link where the record gives one.

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
- JECFA evaluation record.
  Year not recorded · GLOBAL JECFA listing · Read the source →
- JECFA evaluation lists ADI NOT LIMITED. Functional class: acidity regulator, firming agent.
  Year not recorded · GLOBAL JECFA listing · Read the source →

Evidence & sources

No graded research studies for Calcium hydroxide yet. This record is compiled from the published data sources below — registries and regulatory listings, not study findings.

9 data sources

Where this comes from

CosIng
regulatory · updated 2026-09-23
Open →
EU CosIng Cosmetics Regulation Annexes
regulatory · updated 2010-10-17
Open →
EPA Chemical and Products Database
exposure · updated october 6, 2016
Open →
EPA DSSTox Identifiers
chemistry · updated 2025-12-29
Open →
FDA Inactive Ingredient Database
regulatory · updated 2026-01-09
Open →
FDA National Drug Code Directory
regulatory · updated 2026-12-31
Open →
FDA GSRS UNII
registry · updated 2026-02-26
Open →
WHO JECFA Database
regulatory · updated 2026-10-04
Open →
openFDA Substance
registry · updated 2026-05-24
Open →

Reference links (2)

Openfda substance

codexalimentarius.net

Read →

Openfda substance

bcpcpesticidecompendium.org

Read →

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.

Good fit

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.

Good fit

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 EPA CPDat has listed Calcium hydroxide in a product composition. These are source records, not Greenveil catalog products.

Source records

667

Named organisations

Construction and building materialsFurniture and furnishingsRaw materialsOther indirect contact consumer goodsHome maintenanceConstruction

Typical roles

BufferingAcidity regulator, firming agentpH adjuster

See products using Calcium hydroxide →

Catalog

Found in these products

Their ingredient lists include Calcium hydroxide; each product's own rating depends on its whole formula, so it is shown on the product page, not here.

See all 1000+ →Find products without it →