What is benzalkonium chloride used for?

Benzalkonium chloride is a preservative and antimicrobial agent used to prevent bacterial and fungal contamination in cosmetics. It is also used as a conditioning or static-control agent in hair products. Published data supports its safety at typical cosmetic concentrations.

Is benzalkonium chloride safe for skin?

Benzalkonium chloride is approved for use in cosmetics and is considered safe at normal concentrations. At very high levels or with prolonged contact, it can irritate skin. Rinse-off products pose minimal risk; leave-on products use lower concentrations.

Can benzalkonium chloride cause skin irritation or allergies?

Irritation from benzalkonium chloride is more likely at high concentrations or with sensitive skin. Allergic contact dermatitis is possible but uncommon. If you experience reactions to preservatives, patch testing of new products is advisable.

preservative

Benzalkonium Chloride

Watch if sensitive·Strong evidence

A quaternary ammonium antimicrobial used as a preservative and, in scalp products, to keep flaking microbes down. It is an established irritant for some people at higher concentrations, and eye contact should be avoided; at the low levels allowed in cosmetics most people tolerate it without trouble.

Worth knowing

Can irritate, especially left on

The EU caps it at 0.1% as a preservative and requires the label warning "avoid contact with eyes" for some uses.

Questions

What is benzalkonium chloride used for?: Benzalkonium chloride is a preservative and antimicrobial agent used to prevent bacterial and fungal contamination in cosmetics. It is also used as a conditioning or static-control agent in hair products. Published data supports its safety at typical cosmetic concentrations.
Is benzalkonium chloride safe for skin?: Benzalkonium chloride is approved for use in cosmetics and is considered safe at normal concentrations. At very high levels or with prolonged contact, it can irritate skin. Rinse-off products pose minimal risk; leave-on products use lower concentrations.
Can benzalkonium chloride cause skin irritation or allergies?: Irritation from benzalkonium chloride is more likely at high concentrations or with sensitive skin. Allergic contact dermatitis is possible but uncommon. If you experience reactions to preservatives, patch testing of new products is advisable.

Products with Benzalkonium Chloride

References

Cosmetic information for general education, not medical advice. A verdict is a reading of the published evidence, never a guarantee for your skin: any ingredient can irritate someone, so patch test new products and see a professional if you react. Concern is graded on cited evidence, never on hazard-score lists. See how we score.