Is Calcium Oxide safe in cosmetics?
Calcium Oxide has a safety rating of "POOR" in our database. EU status: prohibited. US status: permitted.
Calcium Oxide
Also known as: CaO, Calcium oxide (CaO), Lime, Caloxol CP2, Calx usta (+15 more)
INCI: CALCIUM OXIDE
Calcium Oxide (CAS 1305-78-8) is a cosmetic cosmetic ingredient functioning as Buffering agent. EU Regulation 1223/2009 status: prohibited. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety, pharmaceutical, and food safety data.
View industrial chemical safety profile for CAS 1305-78-8 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
Calcium Oxide is prohibited in EU cosmetics but has active industrial GHS classifications (H302, H314, H315, H318, H335, H303, H304, H370).
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Buffering agent
Safety Rating
POOR
Chemistry & Identifiers
IUPAC Name
oxocalcium
InChIKey
ODINCKMPIJJUCX-UHFFFAOYSA-N
Regulatory Status
EU EU Status
prohibited
US US Status
permitted
US Notes
Conditional — safe only at very low concentrations with strict pH control; MoS inadequate at high concentrations
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Calcium Oxide.
Calculate MoS for your specific formulation with the MoS Calculator.
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Short-term Exposure Effects
The substance is corrosive to the eyes, skin and respiratory tract. The effects may be delayed. Medical observation is indicated.
Long-term Exposure Effects
Repeated or prolonged contact with skin may cause dermatitis. Repeated or prolonged inhalation of dust particles may cause effects on the lungs. Repeated or prolonged inhalation may cause nasal ulceration. This may result in perforation of the nasal septum.
Routes of Exposure
The substance can be absorbed into the body by inhalation of its aerosol and by ingestion.
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
10,000,000 - 100,000,000 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
Additional Ingredient Properties
1 property record from structured ingredient metadata.
mineral_clay
{"cas_number": "1305-78-8", "ingredient_class": "calcium_compound", "chemical_formula": "CaO", "mineral_origin": "synthetic", "particle_size_range_um": "0.5-20", "surface_area_m2_per_g": "1-10", "crystal_structure": "cubic", "color_appearance": "white", "opacity": "opaque", "refractive_index": "1.84", "oil_absorption_g_per_100g": "20-50", "water_absorption_capacity": "low", "surface_charge_at_pH_7…
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (2)
ICSC Safety Card
0409
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Skin Eye Respiratory Irritation
CaO may produce irritation when contact with the skin is repeated or extended. | Eye irritation: highly irritating, Risk of serious damage to eyes. /human/ | Irritating to skin, eyes, and respiratory system.
Source: Hazardous Substances Data Bank (HSDB)
Regulatory (2)
JECFA Evaluation
CALCIUM OXIDE | 1965 | NOT LIMITED | NMRS 40/TRS 339-JECFA 9/16 | FAS 67.29/NMRS 40A,B,C-JECFA 9/158
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
EU Food Improvement
Food additives
Source: EU Food Improvement Agents
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Anti-caking agent
Binder
Catalyst
Degradant/impurity
Dehydrating agent (desiccant)
Dispersing agent
Drier
Dye
Filler
Flavouring and nutrient
Regulatory List Membership (1)
FDA Substances Added to Food (EAFUS)
Expert Verdict
Expert safety assessment and concern-level summary for Calcium Oxide.
Regulatory Flags
fda_food_additive
jecfa_safe
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to Calcium Oxide by CAS number or substance name.
Studies
18
Lowest NOAEL
279.5 mg/kg bw/day
Highest NOAEL
2280 mg/kg bw/day
ECHA_REACH_reach_study_results_dossiers_23-05-2023.zip
Known Synonyms
CaO
Calcium oxide (CaO)
Lime
Caloxol CP2
Calx usta
Caswell No. 147A
Chaux vive
EINECS 215-138-9
EPA Pesticide Chemical Code 075604
Lime, burned
Quick lime
Unslaked lime
Wapniowy tlenek
UNII-C7X2M0VVNH
Aetzkalk
Branntkalk
Kalziumoxid
calx
caustic lime
gebrannter Kalk
Chemical Function
pH regulating agent
Stabilizing agent
Binder
Regulatory Lists
drinking_water; Europe; manufacturing; plastic_additive
inert_ingredient; Pesticides
active_ingredient; animal_products; Europe; pharmaceutical; residue
Europe; supplements
Europe; food_additive; supplements
Europe; plastic_additive
food_additive; Substances Added to Food (formerly EAFUS) (2/2019)
Canada; pharmaceutical
inert_ingredient; non_food_use; Pesticides
active_ingredient; Europe; Pesticides
active_ingredient; Europe; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
Australian Status
AICIS status: listed
Cross-Vertical Safety Context
Same-CAS public records found in pharmaceutical and food safety data.
SOURCE
ChEMBL / DrugCentral / FAERS
DB_PHARMA CAS match
Pharmaceutical Data
Same-CAS rows from the pharmaceutical spoke database.
Compound
LIME
ChEMBL ID
CHEMBL5314372
Max Phase
3
SOURCE
EFSA / FDA GRAS
food_additives
Food Safety Data
Same-CAS food additive or FDA GRAS records from the core public database.
Food Name
Calcium oxide
E Number
E529
ADI
NOT LIMITED mg/kg bw
Food Category
preservative
Frequently Asked Questions
Is Calcium Oxide allowed in the EU?
Calcium Oxide EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does Calcium Oxide do in cosmetics?
Calcium Oxide functions as: Buffering agent. It is classified as a cosmetic ingredient in our database. CAS number: 1305-78-8.
Is Calcium Oxide used outside cosmetics?
Calcium Oxide also appears in industrial chemical safety, pharmaceutical, and food safety data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Does Calcium Oxide have different safety status in cosmetics vs industrial chemicals?
Calcium Oxide is prohibited in EU cosmetics but has active industrial GHS classifications (H302, H314, H315, H318, H335, H303, H304, H370).
Compliance Tools
Check Calcium Oxide compliance across multiple jurisdictions:
Ingredient Decoder
Paste a full ingredient list for instant analysis
82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
Compare limits across jurisdictions
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CALCIUM ASCORBATE
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Browse nearby
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