Salicylic acid

Salicylic acid (CAS 69-72-7) is an organic acid used in pharmaceutical, cosmetic, and food applications for preservative, keratolytic, and stabilizing functions. FEMA 3985.

Where is Salicylic acid used?

• Pharmaceutical: intermediate in aspirin synthesis and active in topical acne treatments
• Cosmetic: exfoliating cleansers, anti-dandruff shampoos, peeling agents with controlled keratolytic action
• Food and beverage: flavoring agent in small-quantity regulated formulations
• It also acts as a preservative in topical and industrial preparations needing microbial control.
• Used as a curing accelerator for polymers in high-performance industrial applications.
• Used in epoxy systems.
• Can be combined with niacinamide for exfoliation plus barrier support and soothing redness.

Good to know: USP, BP, and Ph. Eur. grades are standard for regulated pharmaceutical and cosmetic applications to ensure purity; technical grade suits industrial and intermediate synthesis where compendial certification is not required.

Formulation notes

• Should be pre-dissolved in propylene glycol, ethanol, glycerin, or their combinations before adding to the main phase.
• In cosmetics, typically used at 0.2–2%, with 0.5-1% in toners and daily care products, 1-2% in pore/acne serums, and 0.5-2% in cleansers.
• In scalp care products, usually present at 0.5-3%.

Typical specification

• Assay of at least 99%.
• Heavy metals content of at most 20 ppm.
• Ash content of at most 0.3%.
• Supplied in USP grade as a white colorless crystalline powder.

Regulatory status

• Suspected of damaging the unborn child (H361d).
• Causes serious eye damage (H318).
• High-concentration products (17%+) for corns/warts are considered pharmaceutical and subject to different regulation.
• Has a harmonised CLP classification under Regulation 1272/2008 (CLP).

Storage, packaging and handling

• Should be stored at 15-30 °C in well-closed containers protected from light.
• The crystalline powder form can clump when it absorbs moisture, so the packaging should be tightly closed after each use.
• Sensitive to light and may discolor when exposed to direct sunlight.

Frequently asked questions about Salicylic acid

What are the solubility characteristics of salicylic acid?

Salicylic acid is soluble in alcohol, acetone, and ether.

What purity is typical for technical grade salicylic acid?

Technical grade salicylic acid is obtained by crystallization from aqueous solution at 99.5% purity.

Is salicylic acid approved as a food additive?

Salicylic acid was formerly used as a food preservative but is currently not approved as a food additive.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.