BHA BETA HYDROXY ACID

BHA Beta Hydroxy Acid is a commercial and cosmetic-category designation used primarily for salicylic-acid-based exfoliating systems and, more broadly, for beta-hydroxy-acid ingredients. BHA Beta Hydroxy Acid should not be treated as one single pure chemical substance because the term BHA can refer to a chemical family, a cosmetic functional category, a salicylic-acid raw material, or a formulated BHA solution depending on commercial context. In strict structural chemistry, a beta-hydroxy acid contains a hydroxyl group on the beta carbon relative to the carboxylic acid group, so the broad family has no single CAS Number, EC Number, molecular formula, molecular weight, melting point, solubility or universal hazard classification. In cosmetics and skin care, however, BHA Beta Hydroxy Acid most commonly refers to salicylic acid, CAS Number 69-72-7, EC Number 200-712-3, molecular formula C7H6O3 and molecular weight approximately 138.12 g/mol. Salicylic acid is the principal commercial BHA used for exfoliation, keratolytic skin conditioning, oily-skin formulations, pore-clearing products, acne-related applications, scalp care and professional skin-care systems. Because BHA Beta Hydroxy Acid can describe either a family or a salicylic-acid-centered commercial category, the exact ingredient identity, salicylic acid concentration, solvent system, pH, product type, user population and regulatory market should always be confirmed before formulation or supply.

PRODUCT IDENTITY

Product / Commercial Page Name: BHA Beta Hydroxy Acid
Commercial Category: Beta Hydroxy Acid / BHA exfoliating-acid category
Chemical-Family Basis: Beta-hydroxy carboxylic acids; cosmetic-market usage is centered primarily on salicylic acid
Single CAS Number for BHA Beta Hydroxy Acid: Not applicable unless the supplied product is specifically salicylic acid or another defined single substance
Single EC Number for BHA Beta Hydroxy Acid: Not applicable unless the supplied product is specifically identified
Fixed Molecular Formula for BHA Beta Hydroxy Acid: Not applicable to the category/family term
Fixed Molecular Weight for BHA Beta Hydroxy Acid: Not applicable to the category/family term
Primary Cosmetic Reference Ingredient: Salicylic Acid
Single Physical Form: Not applicable; individual BHAs can be solids, liquids or solutions
Single Melting Point: Not applicable to the family
Single Boiling Point: Not applicable to the family
Single Density: Not applicable to the family
Single Water Solubility: Not applicable to the family
Single Hazard Classification: Not applicable to the family
Salicylic Acid CAS Number: 69-72-7
Salicylic Acid EC Number: 200-712-3
Salicylic Acid CLP Index Number: 607-732-00-5
Salicylic Acid Molecular Formula: C7H6O3
Salicylic Acid Molecular Weight: Approximately 138.12 g/mol
Salicylic Acid IUPAC Name: 2-Hydroxybenzoic acid
Salicylic Acid Physical Form: White to pale-yellow crystalline powder
Salicylic Acid Melting Point: Approximately 158-161°C
Salicylic Acid Density: Approximately 1.44 g/cm³ at 20°C
Salicylic Acid Water Solubility: Approximately 2 g/L at 20°C in commonly cited reference data
Salicylic Acid pKa: Approximately 2.9-3.0
Salicylic Acid log Kow: Approximately 2.2-2.3
Salicylic Acid Flash Point: Approximately 157°C closed cup
Principal Cosmetic Function: Exfoliation / keratolytic skin-conditioning effect
Principal OTC Drug Function in the United States: Acne treatment active ingredient at 0.5-2% under OTC Monograph M006
EU Cosmetic Non-Preservative Use: Up to 3.0% in rinse-off hair products, 2.0% in specified other products and 0.5% in specified more-restricted product categories under the current consolidated cosmetic regulation
EU Cosmetic Preservative Use: Salicylic acid and specified salts can be used up to 0.5% expressed as acid under the applicable Annex V restrictions
Current EU Harmonized Salicylic Acid Classification: Acute Toxicity Category 4, Eye Damage Category 1 and Reproductive Toxicity Category 2 with H302, H318 and H361d
Important Family Principle: Regulatory limits and hazard statements for salicylic acid must not be automatically applied to every other beta-hydroxy acid

SYNONYMS

Because BHA Beta Hydroxy Acid is a category/commercial designation rather than one universally defined molecule, the following list combines true naming variants, cosmetic terminology and salicylic-acid-centered search terms rather than pretending that every entry is an exact chemical synonym.
BHA Beta Hydroxy Acid, Beta Hydroxy Acid, Beta-Hydroxy Acid, β-Hydroxy Acid, BHA, BHA Acid, Beta Hydroxy Acids, Beta-Hydroxy Acids, β-Hydroxy Acids, BHA Exfoliating Acid, BHA Exfoliant, Cosmetic BHA, Skin-Care BHA, Skincare BHA, BHA Skin Exfoliant, BHA Keratolytic Acid, Salicylic Acid BHA, Salicylic Acid Exfoliant, 2-Hydroxybenzoic Acid BHA, Oil-Soluble BHA Exfoliant, Pore-Clearing BHA, Acne-Care BHA, Scalp-Care BHA, BHA Peel Acid, BHA Chemical Exfoliant, BHA Skin-Care Acid, Beta Hydroxy Carboxylic Acid, Beta-Hydroxy Carboxylic Acid, Salicylate-Based BHA, Salicylic Acid Based BHA

WHAT IS BHA BETA HYDROXY ACID?

BHA Beta Hydroxy Acid is best understood as a technical and commercial category name rather than one single chemical identity.
In structural organic chemistry, beta-hydroxy acids are carboxylic acids containing a hydroxyl group on the beta carbon relative to the carboxyl carbon.
In skin-care commerce, BHA Beta Hydroxy Acid is overwhelmingly associated with salicylic acid and salicylic-acid-based exfoliating systems.
This dual meaning explains why some commercial BHA pages use salicylic-acid identifiers while broader technical references describe a family of different beta-hydroxy acids.
A product sold simply as BHA Beta Hydroxy Acid should therefore identify whether the supplied material is pure salicylic acid, a salicylic acid solution, a neutralized salicylate system or a broader BHA blend.
Ataman Chemicals product documentation should control the exact supplied identity, concentration and specification.

BHA BETA HYDROXY ACID COMMERCIAL POSITIONING

BHA Beta Hydroxy Acid is a useful SEO and market designation because BHA is the familiar consumer and formulation abbreviation for beta hydroxy acid.
For cosmetic raw-material commerce, the phrase most commonly points to salicylic acid or to a salicylic-acid-containing BHA solution.
The page title should not be interpreted as proof that every BHA product is chemically identical to salicylic acid.
When the supplied raw material is pure salicylic acid, CAS Number 69-72-7, EC Number 200-712-3, formula C7H6O3 and molecular weight approximately 138.12 g/mol are appropriate.
When the supplied product is a BHA solution or blend, active concentration, solvent composition, water content, pH and additional ingredients must be stated separately.
This distinction prevents incorrect use of pure-salicylic-acid specifications for formulated BHA products.

STRICT CHEMISTRY VERSUS COSMETIC TERMINOLOGY

The distinction between strict chemical nomenclature and cosmetic terminology is important for technically accurate product writing.
A true beta-hydroxy carboxylic acid has the hydroxyl group on the beta carbon of an aliphatic or otherwise carbon-chain-based carboxylic acid framework.
Salicylic acid instead contains a carboxylic acid group and an adjacent phenolic hydroxyl group on a benzene ring.
The cosmetic industry nevertheless uses BHA as the established category name for salicylic acid exfoliation.
U.S. regulatory consumer information also recognizes salicylic acid as the most common cosmetic BHA while noting the strict chemistry distinction.
A professional technical page should therefore preserve both meanings rather than choosing one and presenting the other as simply incorrect.

PRINCIPAL COSMETIC BHA SALICYLIC ACID

Salicylic acid is the most commercially important ingredient associated with Beta Hydroxy Acids (BHAs) in skin care.
Salicylic acid combines aromatic hydrophobic character with a strongly acidic carboxyl group and a phenolic hydroxyl group.
The aromatic ring gives salicylic acid greater lipid affinity than many small alpha-hydroxy acids.
This helps explain its usefulness in sebum-rich skin, follicles and oily formulations.
Salicylic acid also disrupts cohesion between corneocytes in the outer skin layer and is therefore used as a keratolytic and exfoliating ingredient.
Concentration, pH, solvent system, vehicle and exposure time strongly influence actual performance.

OTHER BHA-DESIGNATED INGREDIENTS

U.S. cosmetic guidance has identified beta-hydroxybutanoic acid, tropic acid and trethocanic acid among ingredients that can be listed as BHAs.
These materials should not be assumed to have the same cosmetic performance, regulatory status or hazard profile as salicylic acid.
Beta-hydroxybutanoic acid is structurally a true beta-hydroxy carboxylic acid.
Tropic acid is also a hydroxy carboxylic acid with a different aromatic side-chain structure and different use profile.
Trethocanic acid is a separate specialty ingredient rather than a synonym for salicylic acid.
The phrase BHA blend should therefore always identify the actual chemical composition rather than implying a standardized mixture.

COMMERCIAL FORMS OF BHA BETA HYDROXY ACID

BHA Beta Hydroxy Acid can appear commercially in more than one form.
Pure salicylic acid is generally supplied as crystalline powder.
Cosmetic BHA solutions can contain salicylic acid dissolved in water-compatible organic solvent systems, glycols, alcohols, surfactants or neutralized carriers.
Salicylate salts can be used when greater aqueous compatibility is required, but they do not provide the same free-acid profile at the same nominal concentration.
Micronized salicylic acid can also be incorporated as a controlled suspension rather than a fully dissolved active.
A commercial quotation should therefore identify whether the requested BHA Beta Hydroxy Acid is powder, solution, salt, dispersion or formulated blend.

SALICYLIC ACID PHYSICAL PROPERTIES

Salicylic acid is a crystalline solid under ordinary conditions.
Reference melting range is approximately 158-161°C.
Density is approximately 1.44 g/cm³ at 20°C.
Water solubility is relatively low at room temperature, around approximately 2 g/L in commonly used reference data.
The pKa is approximately 2.9-3.0, making salicylic acid significantly acidic in water.
The log Kow of approximately 2.2-2.3 reflects greater hydrophobicity than many highly water-soluble hydroxy acids.

WATER SOLUBILITY

Low room-temperature water solubility is one of the main formulation challenges for salicylic-acid-based BHA products.
A simple aqueous formula can precipitate salicylic acid when the concentration exceeds its practical solubility.
Solubility can be improved by suitable co-solvents, surfactants, salts, pH adjustment or other formulation technologies.
Neutralizing salicylic acid increases formation of salicylate ion and generally increases aqueous compatibility.
Excessive neutralization can simultaneously reduce the concentration of free acid and therefore alter exfoliation behavior.
A stable BHA formulation must balance chemical solubility, pH, free-acid fraction, skin tolerance and regulatory requirements.

PKA AND IONIZATION

Salicylic acid has a carboxylic-acid pKa of approximately 2.9-3.0.
Below the pKa, a larger fraction remains in the undissociated free-acid form.
Above the pKa, salicylate ion becomes increasingly dominant.
The undissociated form is more lipid soluble and generally penetrates hydrophobic environments more readily.
This makes formulation pH important to performance.
The relationship between pH and free-acid fraction should be considered together with irritation and finished-product stability rather than using the lowest possible pH.

EXFOLIATION MECHANISM

Cosmetic salicylic acid promotes exfoliation by weakening cohesion between cells in the stratum corneum.
The effect is commonly described as keratolytic or desmolytic depending on concentration and scientific context.
Reduced corneocyte cohesion encourages shedding of accumulated surface cells.
In oily skin, the lipophilic aromatic structure also supports distribution into sebum-rich areas and follicular openings.
This combination distinguishes salicylic-acid-based BHA systems from many water-soluble alpha-hydroxy acid systems.
The degree of exfoliation depends strongly on concentration, pH, vehicle, contact time and frequency of application.

KERATOLYTIC EFFECT

Keratolytic action refers to softening and removal of excess keratinized material.
At cosmetic concentrations, salicylic acid supports controlled surface exfoliation and smoother skin texture.
At higher medicinal concentrations, the same chemistry can be used in more intensive keratolytic applications such as callus or wart treatment under appropriate drug regulation.
Cosmetic and medicinal concentration ranges should never be merged into one generic recommendation.
The finished product category and claim determine the regulatory pathway.

SEBUM AND FOLLICULAR USE

Salicylic acid is commonly selected for oily and acne-prone skin because it has useful affinity for lipid-rich environments.
The ingredient can reach follicular openings where sebum and keratinous material accumulate.
This supports formulas marketed for clogged pores, blackheads and oily-skin texture.
Cosmetic products must avoid drug claims unless marketed under the applicable medicinal or OTC framework.
A cosmetic pore-cleansing product and an OTC acne drug can contain the same ingredient but operate under different legal requirements.

BHA BETA HYDROXY ACID FUNCTIONS

Exfoliation
BHA Beta Hydroxy Acid is used primarily for chemical exfoliation, especially in salicylic-acid-based skin-care systems.

Keratolytic action
Salicylic-acid-centered BHA systems reduce cohesion of keratinized surface cells and support controlled shedding.

Pore-focused skin care
BHA Beta Hydroxy Acid is strongly associated with oily, sebum-rich and visibly congested skin because salicylic acid has useful lipid affinity.

Scalp exfoliation
BHA Beta Hydroxy Acid can support removal of scale and keratinized buildup in scalp-care products.

Acne-related applications
Salicylic acid can be used in cosmetic blemish-positioning products or regulated acne-drug products depending on claims and jurisdiction.

Professional peel systems
Higher-intensity BHA Beta Hydroxy Acid formulations are used in professional exfoliation, where concentration, pH, exposure time and product category require tighter control.

Combination acid systems
BHA Beta Hydroxy Acid can be combined with AHAs or PHAs to create multi-acid exfoliating systems when irritation and total acid load are properly managed.

APPLICATIONS

Facial exfoliants
Beta Hydroxy Acids (BHAs), principally salicylic acid, are used in facial exfoliating products designed to remove accumulated surface cells and improve skin smoothness.

Oily-skin products
Salicylic-acid-based BHA formulations are widely used in oily-skin products because the aromatic structure provides useful affinity for sebum-rich environments.

Pore-clearing formulations
BHA skin-care products are used in formulations intended to reduce the appearance of clogged pores and surface congestion without making drug-treatment claims.

Blackhead-focused cosmetics
Cosmetic salicylic acid is commonly used in products positioned for blackhead-prone skin because of its keratolytic and follicular application profile.

Acne OTC drugs
In the United States, salicylic acid is an OTC acne active ingredient at 0.5-2% under Monograph M006 when the product meets all applicable drug requirements.

Acne washes
Rinse-off salicylic acid acne products can deliver controlled active concentration while limiting contact time, subject to the applicable drug monograph or local medicinal regulation.

Acne gels
Leave-on gels can provide targeted salicylic acid delivery where drug or cosmetic status and concentration are properly defined.

Acne lotions
Suspension, hydroalcoholic or emulsion lotions can deliver salicylic acid in regulated acne formulations.

Toners
Cosmetic BHA toners can contain salicylic acid in low-pH solvent systems designed for light exfoliation and oil-control positioning.

Serums
Leave-on BHA serums use controlled salicylic acid concentration and solvent or solubilization systems to provide exfoliating skin-care performance.

Creams
Emulsion creams can contain salicylic acid where the oil-water system maintains stable distribution and the legal concentration is appropriate.

Lotions
Body and facial lotions can contain salicylic acid at category-specific legal levels, with body-lotion restrictions requiring particular attention in the EU.

Peel products
Professional or intensive BHA peel products can use higher acid concentrations under specific professional, cosmetic or medical frameworks depending on jurisdiction.

Scalp exfoliants
Salicylic acid is used in scalp products to loosen scale, reduce surface buildup and support removal of keratinized flakes.

Rinse-off hair products
EU rules allow salicylic acid up to 3% in rinse-off hair products for non-preservative purposes under the current restrictions.

Shampoos
Salicylic-acid-containing shampoos can be cosmetic scale-removal products or medicated products depending on claims and concentration.

Anti-dandruff formulations
Salicylic acid can function as a keratolytic adjunct in anti-dandruff products, while antifungal or drug claims require the applicable regulatory pathway.

Body exfoliants
BHA body products can be formulated for rough skin and surface buildup, subject to product-category restrictions and user-tolerance assessment.

Rough-skin formulations
Salicylic acid is used in products for rough elbows, knees and keratinized body areas where controlled exfoliation is desired.

Keratosis-prone skin care
Cosmetic products can use salicylic acid for smoothing rough texture, while treatment claims for medical disorders require medicinal evaluation.

Foot-care products
Low-level cosmetic BHA products can smooth rough foot skin, while higher-concentration corn or callus treatments fall under drug or medicinal frameworks.

Callus treatments
Salicylic acid is used at higher medicinal concentrations as a keratolytic active for callus removal in regulated products.

Corn removers
Medicinal salicylic acid formulations can be used for corn removal under product-specific OTC or medicinal regulation.

Wart treatments
Higher-concentration salicylic acid is a recognized active ingredient in many wart-removal products, which are not ordinary cosmetic BHA formulations.

Chemical peels
Salicylic acid is used in professional dermatological and cosmetic peel systems where concentration, pH, exposure time and practitioner control determine intensity.

Post-acne texture products
Cosmetic BHA formulations can improve surface texture and appearance after blemishes without making scar-treatment claims unless authorized.

Combination AHA/BHA products
Alpha Hydroxy Acids and Beta Hydroxy Acids can be combined to provide complementary water-phase and lipid-associated exfoliation.

Glycolic acid and salicylic acid blends
Glycolic acid and salicylic acid are commonly combined in exfoliating systems, but total irritation potential and pH must be evaluated carefully.

Lactic acid and salicylic acid blends
Lactic acid can provide humectant and AHA functionality while salicylic acid provides the BHA-type exfoliation profile.

PHA/BHA systems
Polyhydroxy acids can be combined with salicylic acid to balance exfoliation, humectancy and skin tolerance.

Cleansers
Rinse-off facial cleansers can contain salicylic acid for mild exfoliating and oily-skin positioning.

Body washes
BHA body washes can target rough or oily skin while limiting contact time through rinse-off use.

Masks
Clay, gel or cream masks can contain salicylic acid to support oil-control and exfoliation.

Spot products
Localized BHA cosmetic products can target areas of visible congestion, while acne-treatment claims can move the product into drug regulation.

Pre-shave products
Low-level BHA formulations can help remove surface buildup before shaving and can reduce visible follicular congestion.

Ingrown-hair cosmetics
Salicylic acid is used in cosmetic products intended to exfoliate around hair follicles and reduce the appearance of ingrown-hair-prone texture.

After-shave exfoliating products
Controlled BHA levels can support smoothing in post-shave skin-care products when irritation is managed.

Professional skin-care products
Professional-use BHA products can use stronger systems than typical daily cosmetics, subject to jurisdiction and professional-use restrictions.

Dermatological formulations
Salicylic acid is used in regulated dermatological products for keratolysis, acne, scaling conditions and other medicinal indications.

Pharmaceutical keratolytics
High-concentration salicylic acid is used in pharmaceutical products to remove hyperkeratotic tissue.

Topical compounding
Pharmaceutical compounding can use salicylic acid in creams, ointments, collodions or other vehicles under professional medical and pharmacy controls.

Analytical chemistry
Salicylic acid and other beta-hydroxy acids are used as standards, model compounds and derivatization targets in analytical research.

Organic synthesis
True beta-hydroxy acids are intermediates in organic synthesis and can undergo dehydration, oxidation, esterification and decarboxylation reactions 
depending on structure.

Biochemical research
Beta-hydroxybutyrate and related beta-hydroxy acids are studied in metabolic, biochemical and signaling research, which is chemically distinct from cosmetic 
BHA exfoliation.

SALICYLIC ACID SOLUBILIZATION

Salicylic acid has limited water solubility and therefore often requires formulation support.
Common approaches include ethanol, glycols, glycol ethers suitable for the end use, surfactants, hydrotropes, neutralization or mixed solvent systems.
The solvent system must be safe and legal for the intended product category.
A formula can appear clear when warm and then crystallize during cold storage.
Solubility should therefore be evaluated at the lowest expected storage temperature and after water loss or evaporation.
High electrolyte concentration can also change salicylic acid and salicylate solubility.

FREE ACID VERSUS SALICYLATE

Formulation pH controls the balance between free salicylic acid and salicylate ion.
Lower pH increases the proportion of undissociated salicylic acid.
Higher pH increases the proportion of salicylate.
Undissociated salicylic acid has greater lipid-phase affinity and can provide stronger exfoliating activity, but very acidic formulations can also increase irritation.
Neutralized salicylate systems can have improved water solubility but are not functionally identical to the same nominal concentration of free salicylic acid.
Formulators should therefore specify whether concentration is expressed as salicylic acid, a salt, or acid equivalent.

PH CONTROL

pH is one of the most important control variables in salicylic-acid-based BHA formulations.
A pH too high can reduce the free-acid fraction and change performance.
A pH too low can increase irritation, stinging and barrier disruption.
Buffering can improve pH stability during shelf life.
The finished-product pH should be measured after full equilibration rather than calculated only from raw-material addition.
Packaging, water evaporation and ingredient interactions can shift pH over time.

AHA VERSUS BHA

Alpha Hydroxy Acids and Beta Hydroxy Acids are both used as chemical exfoliants, but they differ in structure, solubility and formulation behavior.
Common AHAs such as glycolic acid and lactic acid are highly water compatible.
Cosmetic BHA systems based on salicylic acid are more lipophilic and are commonly positioned for oily or pore-congested skin.
AHAs are frequently used for surface texture, brightness and hydration-related skin renewal.
BHA salicylic acid is especially associated with follicular and sebum-rich applications.
Combination systems can provide broader exfoliation but also increase cumulative irritation.

BHA VERSUS PHA

Polyhydroxy acids generally contain multiple hydroxyl groups and have higher molecular weight or stronger water-phase affinity than salicylic acid.
PHA systems are often positioned as gentler exfoliants with humectant characteristics.
Salicylic-acid-based BHA systems provide stronger lipid-associated exfoliation and pore-focused positioning.
Combining BHA and PHA ingredients can balance efficacy and tolerability.
Finished-product performance should be demonstrated clinically or instrumentally rather than inferred only from acid-family labels.

COSMETIC FORMULATION

A cosmetic BHA formulation must keep salicylic acid dissolved or uniformly dispersed throughout shelf life.
The formulation should also control pH, sensory feel, evaporation and skin irritation.
Hydroalcoholic systems can dissolve salicylic acid efficiently but may feel drying.
Emulsions can provide better moisturization but require careful partitioning and crystallization control.
Anhydrous oils have limited usefulness because salicylic acid is not highly soluble in every cosmetic oil.
Solvent selection should be based on safety, local cosmetics law and final sensory target.

EU COSMETIC USE

The current consolidated EU cosmetics regulation continues to restrict salicylic acid by product category.
For non-preservative purposes, the maximum concentration is 3.0% in rinse-off hair products.
The maximum is 2.0% in other products except the specifically more-restricted categories.
Body lotion, eye shadow, mascara, eyeliner, lipstick and roll-on deodorant are limited to 0.5% under the current Annex III entry.
The current rule also restricts use in products for children under 3 years of age, oral products and applications that may expose the user's lungs by inhalation.
The concentration limits are inclusive of any use of salicylic acid in the product.

EU PRESERVATIVE USE

Salicylic acid and specified salicylate salts are also listed as preservatives under the EU cosmetics regulation.
The current preservative maximum is 0.5% expressed as acid, subject to the applicable product restrictions.
Preservative use and exfoliant use are legally distinct functions.
A product should not add the Annex III and Annex V maxima together as separate allowances.
The current restriction language makes clear that relevant levels are inclusive of any salicylic acid use.
Finished products should be checked against the current consolidated regulation before market release.

CHILDREN 3 TO 10 YEARS

A 2025 European scientific opinion evaluated aggregate exposure to salicylic acid in children aged 3-10 years.
The scientific committee concluded that some existing adult/general-use concentration scenarios were not safe when aggregate exposure across multiple children's products was considered.
For example, the opinion found that 3% rinse-off hair use, 2% selected dermal use and 0.5% body-lotion use were not safe under aggregate-exposure scenarios for children.
The opinion also stated that lower concentrations such as 0.5% rinse-off, 0.15% leave-on and 0.1% oral care were safe under the evaluated proposed scenario.
This 2025 scientific opinion should not be confused with the current consolidated legal concentration table, which remains a separate regulatory instrument.
Children's BHA formulation therefore requires especially careful review of the latest regulation and safety opinions.

UNITED STATES OTC ACNE USE

In the United States, salicylic acid is an active ingredient under OTC Monograph M006 for topical acne drug products.
The permitted concentration range is 0.5-2%.
A product marketed with acne-treatment claims must meet the monograph or another applicable drug pathway.
A cosmetic containing salicylic acid cannot automatically use acne-treatment claims merely because the ingredient is present.
Drug labeling, warnings, directions and manufacturing requirements apply separately from ordinary cosmetic requirements.

COSMETIC CLAIMS VERSUS DRUG CLAIMS

Claim wording can determine whether a salicylic-acid product is treated as a cosmetic or a drug in some jurisdictions.
Claims such as exfoliates, smooths, refines texture or improves the appearance of pores can fit cosmetic positioning when properly substantiated.
Claims to treat acne, remove warts, cure calluses or treat disease can trigger drug or medicinal-product regulation.
The ingredient concentration alone does not determine legal category.
Label, advertising, intended use and presentation must be reviewed together.

SUN EXPOSURE AND SKIN SENSITIVITY

BHA-containing exfoliating products can increase skin irritation or sensitivity in some users.
U.S. cosmetic guidance advises use of sun protection with BHA products and recommends patch testing before broad use.
Salicylic acid does not behave identically to every AHA with respect to photosensitivity, but an exfoliated or irritated skin barrier can respond more strongly to sunlight.
Daily sun protection is therefore a prudent formulation and consumer-use consideration.
The finished product should include appropriate directions and warnings based on its actual composition and test results.

IRRITATION MANAGEMENT

Irritation risk increases with higher free-acid concentration, lower pH, repeated application and combination with other exfoliating or irritating ingredients.
Alcohol-rich vehicles can add dryness or stinging.
Retinoids, benzoyl peroxide, AHAs and physical exfoliation can increase cumulative irritation when used in the same routine.
Humectants, emollients and barrier-support ingredients can improve tolerability.
The finished formula should be tested rather than assuming that a nominal 1% or 2% salicylic acid level has the same irritation profile in every vehicle.

SALICYLIC ACID HAZARD CLASSIFICATION

Current harmonized EU classification for salicylic acid includes Acute Toxicity Category 4, Eye Damage Category 1 and Reproductive Toxicity Category 2.
The associated hazard statements include H302, H318 and H361d.
H302 means harmful if swallowed.
H318 means causes serious eye damage.
H361d means suspected of damaging the unborn child.
These classifications apply to the raw substance and do not mean that every dilute finished cosmetic automatically carries the same classification.

BHA FAMILY HAZARD PRINCIPLE

The BHA family has no single hazard classification.
A beta-hydroxy acid used in biochemical research can have a completely different hazard profile from salicylic acid.
Salts, esters and derivatives can also differ substantially from the parent acid.
A family-level authority page should therefore use individual SDS data for each actual raw material.
Mixture classification must be calculated from ingredient concentrations and the applicable jurisdiction.

BHA BETA HYDROXY ACID SPECIFICATION PRINCIPLE

A specification for BHA Beta Hydroxy Acid should identify the actual active ingredient rather than only the abbreviation BHA.
If the product is pure salicylic acid, specifications should cover salicylic acid assay, identity, melting range, water, related substances and grade-specific impurity limits.
If the product is a solution, the specification should additionally cover active concentration, solvent composition, pH, density, appearance and stability.
If the product is a blend, every BHA active and its concentration should be declared or otherwise technically defined.
A single CAS Number should not be assigned to a multi-ingredient BHA blend unless the product truly consists of one defined substance.
The current Ataman Chemicals TDS, SDS and COA should be used for the exact commercial grade supplied.

QUALITY CONTROL

Quality control for Beta Hydroxy Acids (BHAs) must be ingredient specific.
For salicylic acid, important parameters include identity, assay, appearance, melting range, water, related substances, color, ash or residue and elemental impurities according to grade.
Cosmetic grade, pharmaceutical grade and technical grade can have different impurity specifications.
A BHA solution additionally requires assay, pH, solvent composition, color, density and microbiological or preservative controls where relevant.
A BHA blend should state every active acid and its concentration rather than reporting only one total BHA percentage.
The current Ataman Chemicals specification and batch COA should control commercial acceptance.

SALICYLIC ACID ASSAY

High-purity salicylic acid is commonly controlled by titration, chromatography or another validated assay method.
Assay should be interpreted together with water and related-substance content.
A nominally high assay does not automatically establish cosmetic or pharmaceutical suitability.
The intended grade should define the required impurity profile and documentation.
Pharmaceutical use can require compendial compliance beyond ordinary cosmetic-grade identity.

MELTING RANGE

Salicylic acid has a characteristic melting range around approximately 158-161°C.
A narrow melting range supports identity and purity.
Organic impurities can depress or broaden the melting interval.
Melting range is therefore a useful classical quality-control test alongside chromatographic analysis.

PARTICLE SIZE

Particle size affects dissolution rate when salicylic acid is added as a crystalline powder.
Fine powder dissolves more rapidly but generates more airborne dust.
Coarser grades can reduce dust but require longer mixing or higher temperature.
Suspension products can deliberately use controlled particles rather than complete dissolution.
The product design should distinguish dissolved salicylic acid from micronized suspended salicylic acid.

STORAGE

Beta Hydroxy Acids should be stored according to the SDS for the actual substance.
Salicylic acid should be kept dry, tightly closed and protected from contamination and incompatible strong oxidizers.
Powder should be protected from excessive dust generation.
Solutions should be protected from solvent evaporation because evaporation can increase acid concentration and trigger crystallization.
Low-temperature storage testing is important for concentrated cosmetic BHA solutions.
The current Ataman Chemicals SDS and product specification should control exact storage conditions.

FIRST AID

First aid must follow the SDS of the actual BHA ingredient or mixture.
For concentrated salicylic acid, eye contact requires prompt thorough rinsing and medical attention because the raw substance can cause serious eye damage.
Skin contact should be washed thoroughly and contaminated clothing removed.
Inhalation of dust should be addressed by moving the affected person to fresh air and obtaining medical advice if symptoms occur.
After accidental ingestion of concentrated raw material, professional medical advice should be obtained.
Finished cosmetic first-aid guidance can differ because concentration is much lower.

SPILL MANAGEMENT

Dry salicylic acid powder should be collected in a way that minimizes dust generation.
Fine organic powder dispersed in air can present a dust-explosion hazard under appropriate conditions.
Spilled material should be prevented from entering drains in concentrated quantities.
Solutions containing organic solvents require spill controls appropriate to both the acid and the solvent.
Recovered waste should be handled under local chemical-waste requirements.
The current product SDS should control cleanup procedure.

FIRE RESPONSE

Salicylic acid is combustible but does not ignite as readily as a low-flash-point solvent.
Reference flash point is approximately 157°C closed cup.
Fine powder dispersed in air can present a dust-explosion hazard.
Combustion or thermal decomposition can produce carbon oxides and irritating fumes.
Fire response should follow the current SDS and surrounding-fire conditions.
BHA solutions containing ethanol or other flammable solvents can have a much lower flash point than the salicylic acid raw material.

COMMON FORMULATION PROBLEMS

Customer orders BHA Beta Hydroxy Acid without specifying the form
Clarify whether the requirement is pure salicylic acid powder, a salicylic acid solution, a neutralized salicylate system or a formulated BHA blend before supply.

Customer asks for the CAS Number of BHA Beta Hydroxy Acid
There is no universal family CAS Number. If the product is specifically salicylic acid, CAS Number 69-72-7 applies.

Customer asks for one molecular formula for BHA Beta Hydroxy Acid
The category has no universal formula. Pure salicylic acid is C7H6O3, but BHA blends or solutions require composition-specific documentation.

Customer compares two BHA products only by percentage
Nominal percentage alone is insufficient. Compare active identity, free-acid level, solvent system, pH, neutralization and formulation form.

A BHA solution is labeled with salicylic acid melting point
Melting point around 158-161°C applies to pure salicylic acid, not to a formulated BHA liquid.

A BHA solution is given pure-salicylic-acid density
Formulated BHA solutions have composition-dependent density. Use the actual product TDS and COA.

Salicylic acid crystallizes during storage
The concentration exceeds practical solubility at the storage temperature or the solvent balance has changed. Reduce concentration, improve co-solvent 
balance or reformulate the solubilization system.

Formula is clear when warm but cloudy when cold
Salicylic acid solubility decreases as temperature falls. Perform cold-storage testing and lower the dissolved acid loading if necessary.

Crystals form after water is added
Dilution has reduced solvent strength. Add water gradually and rebalance the co-solvent system.

Crystals form after alcohol evaporates
Loss of volatile co-solvent raises the effective salicylic acid saturation level. Use suitable packaging and reformulate for evaporation tolerance.

pH rises during storage
Buffering, neutralizing ingredients or package interactions can shift pH. Recheck acid-base balance and buffer capacity.

pH is too low
Excess free acid can increase irritation. Adjust carefully while maintaining required salicylic-acid solubility and regulatory compliance.

pH is too high
A larger fraction becomes salicylate ion, which can alter exfoliating performance. Optimize pH rather than targeting solubility alone.

Neutralization improves solubility but performance falls
Increasing salicylate fraction can reduce the undissociated free-acid fraction. Balance free acid and solubility.

BHA toner stings excessively
Free-acid level, pH, alcohol, fragrance or other exfoliants may be too aggressive. Reduce cumulative irritation and retest.

BHA serum pills on skin
Polymer thickener, electrolyte, neutralization level or high solids can create film incompatibility. Rebalance rheology and solvent system.

Emulsion becomes grainy
Salicylic acid may be crystallizing in the aqueous or interfacial phase. Review solubilizer and phase distribution.

Cream separates
Solvent and acid load may destabilize emulsifier structure. Rebuild the emulsion system around the actual BHA solvent package.

Body lotion uses 2% salicylic acid for EU market
Current EU Annex III places body lotion in the more-restricted 0.5% category. Reformulate and verify the latest regulation.

Rinse-off hair product uses more than 3% salicylic acid in the EU
The current Annex III maximum is 3.0% for the relevant non-preservative rinse-off hair use.

Cosmetic preservative uses 1% salicylic acid
Current EU preservative use is limited to 0.5% expressed as acid under the applicable Annex V restrictions.

Product is designed for children under 3
Current EU cosmetic restrictions prohibit salicylic acid in preparations for children under 3 years of age under the applicable entries.

Spray BHA product creates inhalation exposure
Current EU salicylic acid restrictions prohibit applications that may expose the end user's lungs by inhalation.

Oral cosmetic uses salicylic acid without checking restrictions
Current EU Annex III restrictions prohibit oral-product use for the restricted non-preservative salicylic acid application; check the exact regulatory entry and intended function.

Children 3-10 product uses adult maximum concentrations
A 2025 SCCS opinion identified aggregate-exposure concerns for children at several existing maximum-use scenarios. Review the latest child-exposure opinion 
and current law before formulation.

U.S. acne product contains 0.2% salicylic acid but makes acne-treatment claims
OTC Monograph M006 specifies 0.5-2% salicylic acid for covered acne drug products. A 0.2% product does not conform to that monograph active concentration.

U.S. cosmetic makes drug acne claims
Acne treatment is a drug claim. The product must follow the applicable OTC monograph or another drug pathway.

BHA percentage is stated without identifying the ingredient
The term BHA is a family/market category. Identify salicylic acid or the actual beta-hydroxy acid and its concentration.

Supplier lists one CAS Number for all BHAs
The family has no single CAS Number. Each actual chemical must be identified separately.

Supplier lists one molecular formula for BHAs
The family has no single molecular formula or molecular weight.

Salicylic acid is described as a strict beta-hydroxy carboxylic acid
Cosmetic terminology calls salicylic acid a BHA, but strict structural chemistry classifies it as 2-hydroxybenzoic acid rather than a conventional aliphatic beta-hydroxy acid.

True beta-hydroxybutyrate is assumed to exfoliate like salicylic acid
Structural family membership does not guarantee cosmetic exfoliation performance. Ingredient-specific efficacy and safety data are required.

BHA and AHA are added at full separate maxima
Combined exfoliants can increase irritation even when each ingredient is individually legal. Evaluate total acid load and skin tolerance.

BHA is combined with retinoid and skin becomes irritated
Cumulative irritation can be high. Reduce frequency, concentration or overlapping actives and validate the finished regimen.

BHA is combined with benzoyl peroxide and dryness increases
Both actives can increase dryness or irritation. Formulation and consumer directions should manage cumulative exposure.

Formula turns yellow
Oxidation, impurities, fragrance interactions or packaging may be responsible. Investigate color stability and ingredient quality.

Powder does not dissolve during cold processing
Increase mixing time, use a validated co-solvent system or controlled temperature. Do not simply increase neutralizer without considering free-acid fraction.

Salicylic acid precipitates after fragrance addition
The fragrance may change solvent polarity or compete for solubilizer. Re-evaluate the total solvent system.

Surfactant cleanser becomes cloudy after BHA addition
Salicylic acid or salicylate can interact with micelles and electrolytes. Adjust surfactant ratio, pH or solubilization.

Customer asks whether every BHA is oil soluble
No. Lipophilic behavior is strongly associated with salicylic acid in cosmetics, but the broader beta-hydroxy-acid family contains compounds with different solubility.

Customer asks for one universal BHA pH
No universal pH exists. The optimum depends on the specific acid, concentration, free-acid fraction, product type and tolerance target.

Customer asks whether BHAs are safe in pregnancy
Safety depends on the exact ingredient, concentration, route and individual medical context. Raw salicylic acid carries Repr. 2 H361d under EU CLP; consumer-use decisions requiring personal medical advice should be discussed with a healthcare professional.

FREQUENTLY ASKED QUESTIONS

What does BHA Beta Hydroxy Acid mean?
It is a commercial/category term for beta-hydroxy-acid ingredients and, in cosmetics, most commonly refers to salicylic acid or salicylic-acid-based systems.

Is BHA Beta Hydroxy Acid one chemical substance?
No. The phrase can refer to a family, salicylic acid, a salicylic acid solution or a formulated BHA blend.

What CAS Number applies to BHA Beta Hydroxy Acid?
No universal CAS applies to the category. CAS 69-72-7 applies when the supplied material is specifically salicylic acid.

What molecular formula applies to BHA Beta Hydroxy Acid?
No universal formula applies to the category. Pure salicylic acid is C7H6O3.

Can BHA Beta Hydroxy Acid be supplied as a liquid?
Yes. Commercial BHA products can be salicylic acid solutions, neutralized systems or formulated blends; composition must be stated explicitly.

What are Beta Hydroxy Acids (BHAs)?
BHAs are a broad family of hydroxy carboxylic acids; in cosmetics, the term most commonly refers to salicylic acid exfoliation.

Do BHAs have one CAS Number?
No. BHAs are a family and each individual substance has its own CAS Number.

Do BHAs have one molecular formula?
No. Molecular formula and molecular weight depend on the specific beta-hydroxy acid.

What is the main cosmetic BHA?
Salicylic acid is the most commonly used cosmetic BHA.

Is salicylic acid chemically a true beta-hydroxy acid?
In strict structural chemistry, not in the conventional aliphatic sense. Salicylic acid is 2-hydroxybenzoic acid, but cosmetic terminology widely classifies it as a BHA.

What is the CAS Number of salicylic acid?
69-72-7.

What is the EC Number of salicylic acid?
200-712-3.

What is the molecular formula of salicylic acid?
C7H6O3.

What is the molecular weight of salicylic acid?
Approximately 138.12 g/mol.

What is the melting point of salicylic acid?
Approximately 158-161°C.

What is the pKa of salicylic acid?
Approximately 2.9-3.0.

Is salicylic acid soluble in water?
Only slightly. A commonly cited value is approximately 2 g/L at 20°C.

Why is salicylic acid used for oily skin?
Its aromatic structure provides greater lipid affinity than many water-soluble hydroxy acids and supports use in sebum-rich and follicular areas.

How does a BHA exfoliate?
Salicylic acid reduces cohesion between keratinized surface cells and promotes controlled shedding of the stratum corneum.

What is the difference between AHA and BHA?
AHAs are commonly more water compatible and surface focused, while cosmetic BHA salicylic acid is more lipid associated and often used for oily or pore-congested skin.

Can AHA and BHA be combined?
Yes, but total irritation potential, pH and regulatory concentration must be evaluated carefully.

What is the EU maximum for salicylic acid in rinse-off hair products?
The current Annex III maximum for non-preservative use is 3.0%.

What is the EU maximum for salicylic acid in most other cosmetic products?
The current Annex III maximum is generally 2.0%, except for specified more-restricted categories.

What is the EU limit for body lotion?
Current Annex III limits salicylic acid to 0.5% in body lotion.

What is the EU preservative limit?
Salicylic acid and specified salts can be used up to 0.5% expressed as acid under the applicable Annex V restrictions.

Can salicylic acid be used in EU cosmetics for children under 3?
Current restrictions prohibit salicylic acid in preparations for children under 3 years of age under the applicable entries.

Can salicylic acid be used in spray cosmetics that expose the lungs?
Current EU restrictions prohibit applications that may lead to end-user lung exposure by inhalation.

What did the 2025 SCCS children opinion conclude?
It raised aggregate-exposure concerns for children aged 3-10 at several existing maximum-use scenarios and found lower proposed concentrations safe under the evaluated scenario.

What concentration is allowed in U.S. OTC acne products?
Salicylic acid is permitted at 0.5-2% under OTC Monograph M006 for covered topical acne drug products.

Is every salicylic acid product an acne drug?
No. Regulatory status depends on claims, intended use, concentration and product presentation.

What is the current EU hazard classification for raw salicylic acid?
Acute Tox. 4 H302, Eye Dam. 1 H318 and Repr. 2 H361d.

Does that hazard classification apply automatically to a 2% cosmetic?
No. Finished-product classification depends on concentration, formulation and the applicable cosmetic or mixture rules.

Can BHAs crystallize in formulations?
Salicylic acid can crystallize when solvent strength, pH, temperature or concentration changes.

What is the best pH for BHA?
There is no universal value. pH should balance free-acid fraction, solubility, efficacy, tolerance and product stability.

Are all BHAs oil soluble?
No. Salicylic acid is relatively lipophilic, but the broader BHA family contains substances with different solubility profiles.

How should BHAs be stored?
Store each actual BHA according to its product-specific SDS; salicylic acid should be kept dry, tightly closed and protected from incompatible materials.

What documents should be checked before use?
Use the current Ataman Chemicals TDS, SDS and COA for the specific BHA ingredient together with current cosmetic, pharmaceutical or industrial regulations for the intended market.

FINAL TECHNICAL SUMMARY

BHA Beta Hydroxy Acid is a commercial and cosmetic-category designation rather than one universally defined pure chemical.
In cosmetic raw-material use, BHA Beta Hydroxy Acid most commonly refers to salicylic acid or to salicylic-acid-based formulated systems.
Pure salicylic acid has CAS Number 69-72-7, EC Number 200-712-3, molecular formula C7H6O3 and molecular weight approximately 138.12 g/mol.
A BHA solution or blend must use its own composition-specific TDS, SDS and COA rather than inheriting all physical properties of pure salicylic acid.

Beta Hydroxy Acids (BHAs) are a chemical and cosmetic category rather than one standardized substance.
The family has no single CAS Number, EC Number, molecular formula, molecular weight, physical-property set or universal hazard classification.
In strict chemistry, beta-hydroxy acids contain hydroxyl functionality on the beta carbon relative to the carboxyl group.
In cosmetic terminology, salicylic acid is the principal BHA ingredient even though it is structurally 2-hydroxybenzoic acid rather than a conventional aliphatic beta-hydroxy acid.
Salicylic acid has CAS Number 69-72-7, EC Number 200-712-3, molecular formula C7H6O3 and molecular weight approximately 138.12 g/mol.
Key salicylic-acid physical properties include melting range approximately 158-161°C, density about 1.44 g/cm³, pKa about 2.9-3.0 and room-temperature water solubility around 2 g/L.
Cosmetic salicylic acid is used for exfoliation, keratolytic skin smoothing, oily-skin formulations, pore-focused products, scalp care and combination AHA/BHA systems.

Higher-concentration medicinal salicylic acid is used separately in acne, wart, callus and other keratolytic drug products under appropriate regulation.
Current EU cosmetic law allows salicylic acid up to 3.0% in rinse-off hair products, 2.0% in specified other non-preservative uses and 0.5% in specified more-restricted categories including body lotion.
EU preservative use is separately listed at up to 0.5% expressed as acid under the applicable restrictions.
Current EU restrictions also address children under 3, inhalation-exposure applications and oral products.
A 2025 SCCS opinion identified additional aggregate-exposure concerns for children aged 3-10 at several existing maximum-use scenarios, so children's formulations require review of the latest scientific and legal developments.
In the United States, salicylic acid is permitted at 0.5-2% in covered OTC acne drug products under Monograph M006.
Raw salicylic acid currently carries harmonized EU classifications H302, H318 and H361d.
Formulation performance depends strongly on salicylic-acid solubility, pH, free-acid fraction, solvent system, temperature and vehicle.
The term BHA should never be used as a substitute for identifying the actual chemical ingredient in technical specifications or regulatory documents.

For BHA Beta Hydroxy Acid, salicylic acid, BHA solution or blend specifications, formulation support, cosmetic or pharmaceutical documentation, TDS, SDS, COA and commercial supply, contact Ataman Chemicals with the exact requested form, active concentration, application, pH range and regulatory market.

Ataman Chemicals
Phone: +90 216 577 10 10
Email: info@atamankimya.com