Researched by Helena DeMaria-Williams
Formula IngredientPreservativeP-Anisic Acid
INCI: Benzoic Acid, 4-Methoxy-
P-anisic acid (4-methoxybenzoic acid) is a naturally occurring aromatic acid derived from plants, structurally related to benzoic acid with a methoxy group at the para position. It functions primarily as an antifungal preservative in cosmetic formulations, inhibiting fungal and microbial growth to extend product shelf life. It is also listed in the EU CosIng database as a masking agent, meaning it can help suppress undesirable odours in formulations.
Category
Preservative
Irritation Risk
Low
Skin Types
all skin types, oily, dry, combination, sensitive, acne-prone
What does this do in a formula?
preservative, antifungal, antimicrobial, odour masking, extends product shelf life
Is P-Anisic Acid safe? Key considerations
Can P-Anisic Acid cause irritation?
Low RiskAt typical cosmetic-use concentrations (0.1–0.5%), p-anisic acid is well tolerated by most skin types. The raw chemical is classified as an irritant (Xi, R36/37/38) and can cause eye, respiratory, and skin irritation in undiluted form, but this is not a concern at formulated cosmetic concentrations. Not subject to EU Annex II or Annex III restrictions in cosmetic applications.
Does P-Anisic Acid increase sun sensitivity?
No RiskP-anisic acid is not a photosensitising ingredient. No increased sun sensitivity has been reported from its use in cosmetic formulations, and no special UV precautions are required.
Is P-Anisic Acid safe during pregnancy?
CautionMANUAL REVIEW: No specific pregnancy safety studies for topical cosmetic use were identified in available sources. As a benzoic acid derivative, it is considered low risk at typical cosmetic concentrations due to minimal systemic absorption, but no formal MotherToBaby or EWG pregnancy designation was retrievable. Those who prefer to minimise preservative exposure during pregnancy may choose to avoid it, though this is precautionary.
How does P-Anisic Acid work?
P-anisic acid (4-methoxybenzoic acid) is a naturally occurring aromatic acid derived from plants, structurally related to benzoic acid with a methoxy group at the para position. It functions primarily as an antifungal preservative in cosmetic formulations, inhibiting fungal and microbial growth to extend product shelf life. It is also listed in the EU CosIng database as a masking agent, meaning it can help suppress undesirable odours in formulations.
Individuals with known sensitivity to benzoic acid derivatives should review the considerations above before use.
Which products contain P-Anisic Acid?
Shop products that contain P-Anisic Acid
