Ingredient review
Carbon Dioxide
INCI: Carbon Dioxide
Carbon dioxide is a safe, widely used propellant in aerosol cosmetics, but it offers no direct skin benefit.
In plain English
Carbon dioxide (CO2) is a gas that you breathe out. In skincare, it's used to push product out of a can, like in a spray or foam. It doesn't do anything for your skin itself—it's just there to make the product easier to apply.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- natural
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Carbon Dioxide is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Carbon Dioxide.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
Carbon dioxide is a naturally occurring gas that is colorless, odorless, and non-flammable. In cosmetics, it is used as a compressed gas propellant to expel product from aerosol containers.
How it works
When you press the nozzle of an aerosol can, the compressed carbon dioxide gas expands, pushing the product out as a fine mist or foam. It does not interact with the skin or alter the formula's performance.
Pros
Safe and non-flammable
Carbon dioxide is a stable, non-flammable gas, making it a safer propellant choice compared to hydrocarbons like butane or propane.
Enables convenient formats
It allows for spray and foam applications that are easy to use and distribute product evenly, such as in aerosol sunscreens or shaving foams.
Cons and cautions
No skin benefit
Carbon dioxide is purely a delivery mechanism and offers no moisturizing, anti-aging, or other skincare benefits.
Environmental concerns
Aerosol cans contribute to waste, and while CO2 itself is not a volatile organic compound, the can's production and disposal have an environmental footprint.
Best for
- Anyone using aerosol skincare products
- People who prefer spray-on sunscreens or foaming cleansers
Use caution if
- Those concerned about environmental impact of aerosol propellants
- Individuals with respiratory sensitivities who may inhale propellant mist
Usage tips
Safety summary
Carbon dioxide is safe for use in cosmetics as a propellant. It is non-toxic, non-irritating, and non-sensitizing when used as intended. Inhalation of large amounts of propellant mist should be avoided, but typical use poses no health risk.
Research notes
Carbon dioxide has a long history of safe use as a cosmetic propellant. Regulatory agencies like the FDA and the Cosmetic Ingredient Review (CIR) panel have reviewed it and found it safe for its intended use. No significant new research is needed.
Common label clues
- Typical concentration
- Low to moderate, typically under 5% in aerosol formulations
- Regulatory status
- Approved as a cosmetic ingredient and propellant by the FDA and the European Commission, with no known restrictions at typical use levels.
- Common uses
- Aerosol sprays, Foaming products
- Environmental note
- Aerosol cans should be recycled to reduce waste. Carbon dioxide itself is not a greenhouse gas when used as a propellant because it is captured from industrial processes rather than newly emitted.
Good to know
- Carbon dioxide is often used in combination with other propellants to achieve the right pressure and spray pattern
- It is generally considered safe by regulatory bodies when used as directed in cosmetic products
Common questions
What is Carbon Dioxide in beauty products?
Carbon dioxide (CO2) is a gas that you breathe out. In skincare, it's used to push product out of a can, like in a spray or foam. It doesn't do anything for your skin itself—it's just there to make the product easier to apply.
What does Carbon Dioxide do in a beauty product?
When you press the nozzle of an aerosol can, the compressed carbon dioxide gas expands, pushing the product out as a fine mist or foam. It does not interact with the skin or alter the formula's performance.
Is Carbon Dioxide safe for most people?
Carbon dioxide is safe for use in cosmetics as a propellant. It is non-toxic, non-irritating, and non-sensitizing when used as intended. Inhalation of large amounts of propellant mist should be avoided, but typical use poses no health risk.
Who should be careful with Carbon Dioxide?
Those concerned about environmental impact of aerosol propellants Individuals with respiratory sensitivities who may inhale propellant mist
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.