Product Overview

1,3-Dihydroxyacetone (DHA, INCI: Dihydroxyacetone, CAS 96-26-4, C3H6O3, MW 90.08 g/mol, EINECS 202-494-5) is the only FDA-approved sunless tanning active ingredient (21 CFR 73.2150) and one of the most elegantly simple molecules in cosmetic chemistry — just 3 carbons, 2 hydroxyl groups, and 1 ketone group. DHA produces a sunless tan through the Maillard reaction, a non-enzymatic browning reaction first described by Louis-Camille Maillard in 1912. The mechanism proceeds in distinct stages: (1) Schiff base formation — DHA’s electrophilic ketone group (C2) condenses with free nucleophilic amino groups in stratum corneum proteins, primarily the epsilon-amino group of lysine residues, the guanidino group of arginine, and the imidazole group of histidine; (2) Amadori rearrangement — the initially formed Schiff base (imine) undergoes the signature Amadori rearrangement (keto-enol tautomerization), converting the N-substituted glycosylamine to a more stable 1-amino-1-deoxy-2-ketose; (3) Dehydration, fragmentation, and polymerization — the Amadori product undergoes successive dehydration reactions, forming reactive alpha-dicarbonyl intermediates (including reductones and furfurals), which then undergo aldol condensation and cross-polymerization with amino acids and proteins, ultimately producing melanoidin pigments — high-molecular-weight brown chromophores covalently bound to stratum corneum proteins. This entire cascade occurs exclusively in the stratum corneum (the dead, outermost epidermal layer) — DHA does not penetrate to viable epidermis, does not stimulate melanocytes, does not involve melanin synthesis, and has zero systemic absorption. This is the fundamental safety advantage: DHA tanning is a surface-level protein modification, not a biological response. Color develops within 2-4 hours post-application, reaches peak intensity at 24 hours, and fades naturally with desquamation over 5-7 days — the tan literally exfoliates away with dead skin cells. UPOR Biotech produces DHA through fermentation — Gluconobacter oxydans (formerly Acetobacter suboxydans) selectively oxidizes glycerol at the C2 hydroxyl position, converting the secondary alcohol to a ketone. This biotechnological route yields bioidentical DHA that is natural, vegan, and free from synthetic precursors. Purity is absolutely critical for DHA performance: impurities such as formaldehyde (a DHA degradation byproduct), methanol, and pyruvaldehyde (methylglyoxal) directly cause the consumer complaints that plague low-quality self-tanners — orange/unnatural tones, streaking, chemical odor, and skin irritation. UPOR’s >=99% HPLC grade with formaldehyde content strictly controlled at <=10 ppm ensures clean, natural-looking tan development without orange cast. DHA + Erythrulose synergy: DHA (3-carbon ketose, fast-acting, 2-4h onset, golden-brown tone) combined with erythrulose (4-carbon ketose, slow-acting, 24-48h onset, reddish-brown tone) produces the most natural, longest-lasting sunless tan — immediate color satisfaction from DHA with sustained, fade-resistant color from erythrulose.

As a leading DHA manufacturer and bulk supplier, UPOR Biotech provides high-purity 1,3-dihydroxyacetone powder for B2B cosmetic brands, contract manufacturers, private-label self-tanning lines, professional spray tan solution producers, and OEM formulators worldwide. The global sunless tanning market continues to expand rapidly — driven by increasing awareness of UV-related skin cancer and photoaging, consumer demand for safe alternatives to traditional tanning beds and sun exposure, and the growing “skin-vestment” trend where consumers prioritize skincare benefits even in cosmetic color products. DHA-based self-tanning products are positioned as the definitive safe tanning solution: natural, vegan, cruelty-free, and completely UV-independent. Unlike UV tanning (which causes DNA damage, collagen degradation, immunosuppression, and significantly elevated melanoma and non-melanoma skin cancer risk), DHA tanning carries none of these risks because it operates entirely at the dead stratum corneum surface. UPOR offers OEM and private label formulation support with flexible MOQ starting at 1 kg. Free sample available for qualified B2B buyers. Every shipment includes full documentation: COA with HPLC purity and formaldehyde content, MSDS, HPLC chromatogram, and stability data.

DHA vs Erythrulose — The Sunless Tanning Agent Comparison: Why DHA (C3H6O3) Is the Fast-Acting Maillard Reactant for 2-4 Hour Color Development

Comparing the two clinically validated sunless tanning actives reveals complementary — not competitive — mechanisms. Both operate through the Maillard reaction with stratum corneum amino acids, but their kinetics and color profiles differ fundamentally. DHA (1,3-Dihydroxyacetone, C3H6O3, 3-carbon ketose) is the fast-acting Maillard reactant: with only 3 carbons (the smallest cosmetic active molecule), DHA has the highest amino group accessibility and fastest Schiff base formation rate. Color onset: 2-4 hours; peak: 24 hours; produces a warm golden-brown melanoidin tone. DHA is the ONLY FDA-approved sunless tanning active (21 CFR 73.2150) and the industry gold standard since the 1960s. Erythrulose (C4H8O4, 4-carbon ketose) is the slow-acting Maillard reactant: the additional carbon reduces reaction kinetics, producing a more gradual, uniform color development. Color onset: 24-48 hours; peak: 48-72 hours; produces a cooler, more natural reddish-brown tone with superior fade resistance (7-10 days vs. DHA’s 5-7 days). Erythrulose alone produces almost no immediate visible color — it is not suitable as a sole tanning agent. The optimal strategy: DHA 3-5% + Erythrulose 1-3% in combination. DHA provides the immediate 2-4 hour visible tan that consumers expect; erythrulose provides sustained, even color that develops as DHA begins to fade, extending total tan duration and eliminating the “patchy fade” problem. This synergy produces the most natural-looking, longest-lasting sunless tan achievable. Key purity considerations: both DHA and erythrulose must be high-purity (>=99% and >=95% HPLC respectively) to avoid orange tones, streaking, and odor. Neither DHA nor erythrulose stimulates melanocytes, involves UV radiation, or penetrates beyond the stratum corneum — making this combination the safest possible tanning approach.

Technical Specifications

PropertySpecification
Product Name1,3-Dihydroxyacetone (DHA) Powder — Cosmetic Grade (>=99% HPLC) / Standard Grade (>=98%)
INCI NameDihydroxyacetone
CAS Number96-26-4
EINECS Number202-494-5
Molecular FormulaC3H6O3
Molecular Weight90.08 g/mol
Common Name / SynonymsDHA; 1,3-Dihydroxypropan-2-one; Glycerone; 1,3-Dihydroxy-2-propanone; Dihydroxyacetone; Bis(hydroxymethyl) ketone; Sunless Tanning Agent; Protosol
SourceFermentation-derived (Gluconobacter oxydans / Acetobacter oxidation of glycerol) — natural, bioidentical, vegan, Non-GMO
Type ClassificationNon-HA Bioactive — 3-carbon ketose (C3H6O3); the smallest functional cosmetic active molecule
AppearanceWhite to off-white crystalline powder; hygroscopic
OdorCharacteristic mild odor; high-purity (>=99% HPLC) material has minimal odor; low-purity material develops pungent odor from formaldehyde and pyruvaldehyde impurities
Assay (Cosmetic Grade)>=99.0% (HPLC, anhydrous basis)
Assay (Standard Grade)>=98.0% (HPLC, anhydrous basis)
IdentificationIR spectrum conforms to reference standard; HPLC retention time matches DHA reference standard; Melting point 75-80 degrees C (dimer form)
Melting Point75 – 80 degrees C (dimeric crystalline form); monomeric DHA exists in solution as a mixture of monomer, dimer, and hydrated forms
Loss on Drying<=0.5% (60 degrees C, vacuum, 4 hours)
Residue on Ignition<=0.1%
pH (5% Aqueous Solution)3.0 – 6.0 (freshly prepared solution)
pH Stability — Maillard Reactivity (Skin Surface)Optimal pH 3.0 – 6.0. DHA’s ketone group is most electrophilic and amino-reactive under mildly acidic conditions (pH < 6), maximizing Schiff base formation rate with stratum corneum amino groups.
pH Stability — Formulation StabilityOptimal pH 5.0 – 7.0 for finished product shelf stability. DHA degrades via keto-enol tautomerization and aldol condensation at pH < 3 (rapid) and pH > 7 (base-catalyzed degradation to lactic acid, formaldehyde, and colored polymers). Formulate at pH 5.0-5.5 for optimal balance of stability and reactivity.
Maillard ReactivityKetone group (C2) undergoes nucleophilic attack by free amino groups (epsilon-NH2 of lysine, guanidino of arginine, imidazole of histidine) in stratum corneum proteins. Schiff base formation followed by Amadori rearrangement, dehydration, and melanoidin polymerization. Color onset: 2-4 hours. Peak color: 24 hours. Duration: 5-7 days (natural desquamation). Reactivity is pH-dependent, temperature-dependent, and purity-dependent — impurities compete for amino binding sites and produce off-color chromophores.
Formaldehyde Content (CRITICAL)<=10 ppm (HPLC headspace GC-MS). Formaldehyde is the primary DHA degradation impurity — formed via retro-aldol cleavage and base-catalyzed degradation. Formaldehyde > 10 ppm causes: skin sensitization, pungent chemical odor, orange cast, and consumer irritation complaints. THIS IS THE MOST CRITICAL QUALITY PARAMETER for DHA — it directly determines product odor, color quality, and safety profile. UPOR’s >=99% HPLC grade guarantees <=10 ppm formaldehyde.
Pyruvaldehyde (Methylglyoxal) Content<=50 ppm (HPLC). Pyruvaldehyde forms via DHA dehydration and oxidation. Elevated pyruvaldehyde produces orange/unnatural tan tones and increased skin sensitization potential.
SolubilityFreely soluble in water (>250 mg/mL at 25 degrees C); soluble in ethanol (approx. 10 mg/mL); slightly soluble in acetone; practically insoluble in non-polar organic solvents. DHA in aqueous solution exists as an equilibrium mixture of monomer (approx. 70%), dimer (approx. 20%), and hydrated gem-diol forms (approx. 10%).
Heavy Metals (Total)<=10 ppm (as Pb)
Elemental ImpuritiesPb <=2 ppm; As <=1 ppm; Hg <=1 ppm; Cd <=1 ppm (ICH Q3D compliant)
Microbial LimitsTAMC <=100 CFU/g; TYMC <=10 CFU/g (USP <61> / EP <2.6.12>); Pathogens (E. coli, Salmonella, S. aureus, P. aeruginosa) — Absent in 10 g (USP <62> / EP <2.6.13>)
Residual SolventsUSP <467> / ICH Q3C Class 3 compliant
Recommended Usage Rate (Cosmetic)Light/gradual tan: 1-3%; Standard self-tan: 3-5%; Dark tan: 5-10%; Professional spray tan: 8-15%. Add to aqueous phase at 25-40 degrees C; never heat above 40 degrees C.
Storage Conditions (CRITICAL)Hygroscopic — store tightly sealed in original container with desiccant at 15-25 degrees C; protect from moisture, heat (>40 degrees C), and light. DHA is highly hygroscopic: moisture absorption causes caking, dimerization, and accelerated degradation to formaldehyde and lactic acid. Opened containers must be resealed immediately and used promptly. Do not refrigerate (condensation risk).
Shelf Life2 years from date of manufacture under recommended storage conditions (tightly sealed, 15-25 degrees C, desiccated, protected from light)
Grade / StandardsCosmetic Grade (>=99% HPLC) / Standard Grade (>=98% HPLC); EcoCert/COSMOS-compliant grades available upon request
CertificationsISO 9001:2015, ISO 22000, HACCP, FDA Facility Registration, HALAL, KOSHER, Non-GMO, BSE/TSE-Free
Packaging1 kg / 5 kg / 10 kg sealed aluminum foil bags with PE liner and desiccant; 25 kg fiber drums with double PE liner and desiccant. All packaging includes moisture-proof barrier and tamper-evident seal.

Key Benefits — 1,3-Dihydroxyacetone (DHA)

THE Only FDA-Approved Sunless Tanning Active — Clinically Validated Safety Since 1960s

DHA is the sole sunless tanning ingredient with FDA approval (21 CFR 73.2150) for topical cosmetic use. Affects only the stratum corneum (dead layer) — zero systemic absorption, zero melanocyte stimulation, zero UV DNA damage. Fermentation-derived, natural, bioidentical, and vegan.

FDA 21 CFR 73.2150

Maillard Reaction Chemistry — Fast 2-4 Hour Color Development with Natural-Looking Results

DHA’s ketone group reacts with stratum corneum amino acids (lysine, arginine, histidine) via Schiff base formation, Amadori rearrangement, and melanoidin polymerization. Color onset in 2-4 hours, peaks at 24 hours. Purity >=99% HPLC ensures clean, natural tan without orange cast or streaking.

Maillard Reaction

Purity Is Performance — >=99% HPLC with Formaldehyde <=10 ppm

DHA impurities (formaldehyde, methanol, pyruvaldehyde) directly cause streaking, orange tones, and odor. UPOR’s >=99% HPLC Cosmetic Grade with formaldehyde strictly controlled at <=10 ppm guarantees clean, consistent color development batch after batch. The most critical quality parameter in DHA sourcing.

>=99% HPLC | <=10 ppm CH2O

Fermentation-Derived — Natural, Bioidentical & Vegan with EcoCert/COSMOS Available

Produced via Gluconobacter oxydans fermentation from glycerol — not synthetic, not animal-derived. Bioidentical to endogenous DHA (a natural glycolytic intermediate in all living cells). EcoCert/COSMOS-compliant grades available. The definitive natural, vegan, and cruelty-free sunless tanning solution — safe alternative to UV tanning.

Natural & Vegan

Applications

Self-Tanning Lotions, Creams & Mousses

DHA at 3-5% in self-tanning lotions, creams, and mousses — the core format for consumer sunless tanning. Formulate at pH 5.0-5.5 for optimal stability and color development. Combine with erythrulose 1-2% for longer-lasting, fade-resistant color. OEM and private label formulations available with flexible MOQ starting at 1 kg.

Professional Spray Tan Solutions

DHA at 8-15% in professional spray tan solutions for salon and spa application. High-concentration DHA delivers deep, immediate color for professional results. Requires trained application for even coverage. EcoCert/COSMOS-compliant grades available for organic-certified professional lines.

Gradual Tan Daily Moisturizers

DHA at 1-3% in daily gradual tan body and face moisturizers — the fastest-growing self-tan segment. Low-concentration DHA builds subtle, natural color over 3-5 days of continuous use. Ideal for year-round, maintenance tan products that combine skincare with sunless color.

Tan-Enhancing Drops & Concentrates

DHA at 10-15% in concentrated tan-enhancing drops — consumers add 2-5 drops to their daily moisturizer for customizable color intensity. The most versatile DHA format: adjustable concentration, compatible with existing skincare routines, and growing rapidly in consumer preference.

Sunless Tanning Serums & Treatment Hybrids

DHA at 2-5% combined with skincare actives (niacinamide, hyaluronic acid, peptides) in cosmeceutical sunless tanning serums. The “skin-vestment” trend drives demand for tanning products that also deliver anti-aging, hydrating, and brightening benefits — DHA + skincare in a single product.

Tinted Tanning Mists & Instant Bronzers

DHA at 2-5% in tinted tanning mists with temporary cosmetic colorants for instant gratification + developing Maillard tan. The dual-action format: immediate bronze from mineral pigments/caramel, lasting 5-7 day tan from DHA. Ideal for event-ready, wash-off-resistant sunless tanning products.

Frequently Asked Questions

1,3-Dihydroxyacetone (DHA, CAS 96-26-4, C3H6O3, MW 90.08 g/mol) is the only FDA-approved sunless tanning active ingredient (21 CFR 73.2150). DHA creates a sunless tan through the Maillard reaction — a non-enzymatic browning reaction between DHA’s ketone group (C2) and free amino groups (epsilon-amino of lysine, guanidino of arginine, imidazole of histidine) in stratum corneum proteins. The reaction proceeds via: (1) Schiff base formation — condensation of DHA’s ketone with protein amino groups; (2) Amadori rearrangement — keto-enol tautomerization to a stable 1-amino-1-deoxy-2-ketose; (3) Dehydration, fragmentation, and polymerization — formation of reactive alpha-dicarbonyls that cross-polymerize into melanoidin pigments (brown chromophores) covalently bound to stratum corneum proteins. Color develops within 2-4 hours, peaks at 24 hours, and lasts 5-7 days (natural desquamation). Crucially, DHA ONLY affects the stratum corneum (dead layer) — there is no systemic absorption, no melanocyte stimulation, and no UV damage. With only 3 carbons, DHA is the smallest functional cosmetic active molecule. UPOR Biotech produces fermentation-derived DHA (Gluconobacter oxydans oxidation of glycerol) — natural, bioidentical, and vegan.

DHA delivers the safest sunless tan available: (1) FDA-approved and clinically validated since the 1960s as the only sunless tanning active with regulatory approval (21 CFR 73.2150), (2) stratum corneum only — zero systemic absorption, no melanocyte stimulation, no UV-induced DNA damage or photoaging, (3) fermentation-derived, natural, bioidentical, and vegan — produced from glycerol via Gluconobacter oxydans, (4) clean, natural-looking tan in 2-4 hours when using high-purity DHA. Purity >=99% HPLC is CRITICAL because DHA impurities directly determine color quality and user experience: formaldehyde causes skin irritation and pungent chemical odor, methanol contributes to streaking and uneven color, pyruvaldehyde (methylglyoxal) produces orange/unnatural tones, and dimeric/polymeric DHA degradation products reduce Maillard reactivity and produce patchy, inconsistent results. UPOR’s >=99% HPLC grade with formaldehyde content strictly controlled at <=10 ppm ensures: no orange cast, no streaking, minimal odor, consistent batch-to-batch color development, and maximum Maillard reactivity with stratum corneum proteins. Low-purity DHA is the single most common cause of consumer dissatisfaction with self-tanning products — investing in >=99% HPLC purity is the most impactful formulation decision for sunless tanning brands.

Recommended DHA usage rates by product type: Light/gradual tan moisturizers — 1-3% DHA; Medium self-tanning lotions, creams, sprays, and mousses — 3-5% DHA; Dark/double-dark tan formulations — 5-10% DHA; Professional spray tan solutions — 8-15% DHA (applied by trained technicians). Formulation guidelines: DHA is freely water-soluble (>250 mg/mL at 25 degrees C) — add to the aqueous phase at 25-40 degrees C; never heat above 40 degrees C (DHA degrades via retro-aldol cleavage to formaldehyde and lactic acid). Formulate at pH 5.0-5.5 for optimal balance of DHA stability (degrades rapidly at pH <3 and pH >7) and Maillard reactivity on skin (optimal at pH 3-6). For best results: use >=99% HPLC purity DHA with formaldehyde <=10 ppm; include erythrulose 1-3% for longer-lasting, fade-resistant color (DHA provides 2-4h immediate color + erythrulose provides 24-48h sustained color); add a chelating agent (EDTA or sodium phytate at 0.05-0.1%) to chelate metal ions that catalyze DHA degradation; include a humectant (glycerin, propanediol) to moderate DHA’s hygroscopicity; use opaque, airtight packaging with minimal headspace; and never combine DHA with primary amines, strong reducing agents, or high-pH ingredients in the same phase. Typical formulation pH: 4.0-5.5 for lotions and creams; 5.0-6.0 for spray solutions. Always conduct accelerated stability testing (40 degrees C/75%RH for 3 months minimum) to verify DHA content, pH stability, and color performance over shelf life.

DHA and erythrulose are the only two clinically validated Maillard-reaction sunless tanning actives, and they work synergistically. DHA (C3H6O3, 3-carbon ketose) is the fast-acting Maillard reactant: color onset 2-4 hours, peaks at 24 hours, produces a warm golden-brown melanoidin tone, lasts 5-7 days. DHA is the ONLY FDA-approved sunless tanning active (21 CFR 73.2150) and the industry gold standard since the 1960s. Erythrulose (C4H8O4, 4-carbon ketose) is the slow-acting Maillard reactant: the additional carbon slows reaction kinetics; color onset 24-48 hours, peaks at 48-72 hours, produces a cooler, more natural reddish-brown tone, lasts 7-10 days with superior fade resistance. Erythrulose alone produces almost no immediate visible color — it is not suitable as a sole tanning agent. The optimal formulation strategy: DHA 3-5% + Erythrulose 1-3% in combination — DHA provides the 2-4 hour immediate tan consumers expect; erythrulose provides sustained, even color that develops as DHA fades, eliminating the “patchy fade” problem and extending total tan duration. Other “tanning” agents (caramel, walnut extract, beta-carotene, annatto) are NOT true sunless tanning actives — they are temporary cosmetic colorants (direct dyes) that sit on the skin surface and wash off with water or within 24 hours. They do not undergo the Maillard reaction, do not bind to stratum corneum proteins, and do not produce a lasting tan. DHA vs UV tanning: UV tanning stimulates melanocytes via UVB/UVA radiation, causing DNA damage (cyclobutane pyrimidine dimers, 6-4 photoproducts), collagen degradation (MMP upregulation), immunosuppression, and significantly elevated risk of melanoma (75% increase with one indoor tanning session before age 35) and non-melanoma skin cancer. DHA tanning avoids all of these risks by operating entirely at the dead stratum corneum surface — making it the definitive safe tanning solution.

Every shipment includes: COA (HPLC purity >=99.0% cosmetic grade or >=98.0% standard grade, full impurity profile including formaldehyde content <=10 ppm by headspace GC-MS, pyruvaldehyde <=50 ppm, methanol, heavy metals <=10 ppm with Pb <=2 ppm / As <=1 ppm / Hg <=1 ppm / Cd <=1 ppm, residual solvents per USP <467>/ICH Q3C, microbial panel per USP <61>/<62> and EP <2.6.12>/<2.6.13>), MSDS, HPLC Chromatogram (signed and dated), Formaldehyde Content Certificate (headspace GC-MS, <=10 ppm — the most critical quality document for DHA), EcoCert/COSMOS Compliance Certificate (upon request for compliant grades), BSE/TSE-Free Statement, Non-GMO Statement, Allergen Statement, HALAL Certificate, KOSHER Certificate, ISO 22000 + HACCP, ISO 9001:2015, FDA Facility Registration, Stability Data (25 degrees C/60%RH real-time 24-month and 40 degrees C/75%RH accelerated 6-month, including DHA content retention, formaldehyde evolution, and color performance), and Complete Lot Traceability from fermentation batch (Gluconobacter oxydans strain, glycerol source, fermentation conditions) to finished product. Free sample available for qualified B2B buyers. MOQ: 1 kg. All documents provided in English. Custom documentation packages available for regulatory submissions upon request.