Zinc pyrithione (or pyrithione zinc) is a coordination complex of zinc.
It has fungistatic (that is, it inhibits the division of fungal cells) and bacteriostatic (inhibits bacterial cell division) properties and is used in the treatment of seborrhoeic dermatitis.
IUPAC name: bis(2-pyridylthio)zinc 1,1'-dioxide
Other names: ZnP, Pyrithione Zinc, Zinc OMADINE, ZnPT
CAS Number: 13463-41-7
Zinc pyrithione is an antibacterial and antifungal agent. It is found in dandruff shampoo and cosmetic products for the treatment of skin problems.
Zinc Pyrithione (ZPT) is also known as Zinc Omadine or Bis [(2- pyridyl-1-oxo)-thio] zinc, is a complex coordination of zinc element.
Zinc Pyrithione is used as a preservative in rinse off products excluding oral hygiene products, with a small amount of concentration i.e. 0.5%-1%.
Zinc pyrithione have capabilities to remove the dandruff, and it also acts as an anti-virus in personal care products such as anti-dandruff shampoos, lotions, seborrhoeic dermatitis, among others.
Furthermore, Zinc Pyrithione is used in pharmaceutical and medical applications for treatment related to dermatitis, seborrheic, etc.
Zinc Pyrithione is also used as a food preservative in food & beverages industries.
The corrosion of zinc pyrithione is very slow in presence of sunlight due to which it is widely consume by paint and coatings manufacturing industry.
In addition to zinc pyrithione is also used as antibacterial treatment for household sponges. Furthermore being low soluble in water, due to which zinc pyrithione is also used in paint industry and other adhesive products as an antimicrobial agent because zinc pyrithione provide protection from algae.
The zinc pyrithione market growth is expected to be leveraged owing to its demand from the target end use industries.
The use of antibacterial coating in several applications such as food and beverages, textile and paints & coating industries for anti-bacterial activities is considered as a primary reason driving the growth of zinc Pyrithione.
Furthermore, the growth and augmented demand of personal care products is another crucial factor which has been considered boost the growth of global zinc pyrithione market.
The cosmetics industry has developed due to increasing procurement of the related products across the world. The manufacturing of grooming products such as soap and shower segment as well as disinfectants and anti-septic products is expected to imbibe profound quantities of key ingredients including Zinc Pyrithione which is thus anticipated to grow at a substantial rate of its consumption resulting in augmented market size.
The zinc pyrithione market growth is also expected to gain further traction owing to demand from several other materials such as adhesives, carpet backing, cables, and foam stuffing for cushions, wire insulation and other coverings, etc. as a preservative.
However, the strict regulatory rules mandated by the government on the production of zinc pyrithione may restrain the market growth to an extent for its hazardous effects on ecosystem and living organisms on direct exposure. Also, the fluctuation in the price of raw material for production may affect the consumption of pyrithione with end users opting for substitute ingredients.
Zinc Pyrithione has antibacterial and antifungal properties and is effective against many pathogens.
Pyrithione zinc, or zinc pyrithione or zinc pyridinethione, is a coordination complex consisted of pyrithione ligands chelated to zinc (2+) ions via oxygen and sulfur centers.
In the crystalline state, it exists as a centrosymmetric dimer.
Due to its dynamic fungistatic and bacteriostatic properties, pyrithione zinc is used to treat dandruff and seborrheic dermatitis.
Dandruff is a common scalp disease affecting >40% of the world's adult population, and may be caused by fungi such as Malassezia globosa and M. restricta 3.
Pyrithione zinc is commonly found as an active ingredient in OTC antidandruff topical treatments such as shampoos.
Zinc Pyrithione mediates its action by increasing the cellular levels of copper, and damaging iron-sulfur clusters of proteins essential for fungal metabolism and growth.
Due to low solubility, pyrithione zinc released from the topical formulations is deposited and retained relatively well onto the target skin surfaces.
Other uses of pyrithione zinc include additive in antifouling outdoor paints and algaecide.
While its use has been approved in the early 1960's by the FDA 4, safety and effectiveness of pyrithione zinc has been reported for decades.
It is not shown to have any significant estrogenic activity according to the in vivo and in vitro assays
Zinc Pyrithione has antibacterial and anti-fungal properties and is effective against many pathogens.
Zinc Pyrithione can be used as a preservative in formulations, but can also be included into hair care formulations as a hair conditioning agent that can improve the texture of hair as well as preventing and treating dandruff.
Zinc Pyrithione can be used in skin care products to control seborrheic dermatitis and psoriasis.
Zinc Pyrithione can be used in personal care and cosmetic products in the formulation of cleansing products, hair conditioners, shampoos, eyeliners, face powders and skin care products.
Pyrithione zinc is an antibacterial and antifungal agent developed by scientists in the 1930's. Since then it has been used to treat seborrheic dermatitis of the scalp and other skin conditions such as eczema, athlete's foot, and vitiligo, as well as psoriasis. Because of its antifungal properties, it is commonly found in dandruff shampoo. Products containing pyrithione zinc are available today with and without prescription, and it is the main ingredient in many over-the-counter creams, lotions, soaps, and shampoos. It also has antibacterial properties and is effective against many pathogens from the Streptococcus and Staphylococcus genera. Pyrithione zinc`s other medical applications include treatments of psoriasis, eczema, ringworm, fungus, athletes foot, dry skin, atopic dermatitis, tinea, and vitiligo. Its antifungal effect is thought to derive from its ability to disrupt membrane transport by blocking the proton pump that energizes the transport mechanism.
Use: Zinc OMADINE products are highly active, broad spectrum antimicrobial agents that are registered around the world for use in both personal care as well as industrial product applications. In the U.S., Zinc OMADINE® products are approved for use by the EPA and allowed by the FDA. Zinc OMADINE™ fungicide-algaecide is the zinc complex of pyrithione.
Zinc OMADINE fungicide-algaecide is the active ingredient in some of the leading antidandruff shampoo products around the world, and its proven combination of efficacy and safety-in-use has made it the world's leading anti-dandruff agent for more than 30 years. Zinc OMADINE™ fungicide-algaecide is listed in the FDA Final Monograph on Dandruff and Seborrheic Dermatitis as a Category I substance (i.e. generally recognized as safe and effective). Zinc OMADINE® products are available in Industrial and Cosmetic grades, and in powder and in dispersion forms.
Zinc pyrithione (also known as Zinc Omadine or Zinc 2-pyridinethiol-1-oxide) is used to prevent microbial degradation and deterioration of manufacturing starting materials such as plastics, polymers, and latexes, and in a wide range of finished articles made from these starting materials. The chemical acts to prevent the growth of bacteria, fungi, mildew, and algae that can cause various types of deterioration such as discoloration, staining, odors, etc.
Zinc pyrithione is used to preserve a wide variety of food/drinking water contact, and non-food contact articles such as: adhesives; carpet fibers; carpet backings; rubber or rubber-backed bath mats; foam underlay for carpets; synthetic, non-leather materials; foam stuffing for cushions and mattresses; wire and cable insulation; vinyl, linoleum, tile and other synthetic floor coverings; wall coverings; plastic furniture; athletic flooring and mats; mattress liners, covers or ticking; molding; mats; gaskets; weather stripping; coated fabrics for furniture cushions, boat covers, tents; tarpaulins and awnings; rubber gloves (non-surgical); garbage bags, cans, and other refuse containers; bathtub appliques; garden hose; pipe (non-potable water); ductwork; air filters; air filtration components and media for industrial, hospital, residential, and commercial heating and cooling; conveyor belts; shower curtains; sponge or fiber mops; household use sponges; toilet brush receptacles; toothbrush receptacles (non-bristle contact); scrub brushes (non-medical); sink mats and drain boards; storage containers; soap dish holders; towel bars; components of uppers in footwear.
Zinc pyrithione is also registered for incorporation into antifoulant boat paints to control the growth of slime, algae, and marine fouling organisms (e.g., barnacles, tubeworms, etc.) below the water line on recreational and commercial boat hulls.
The largest use for zinc pyrithione is non-pesticidal (i.e., control of dandruff, seborrheic dermatitis, and psoriasis), and is regulated by the Food and Drug Administration. It is the active ingredient in many anti-dandruff shampoo
Zinc pyrithione is incorporated into various polymers and plastics as a liquid, powder, or aqueous dispersion, during the manufacturing process of these materials, and during the manufacture of finished articles from these materials. Zinc pyrithione is added usually by metering pump if it is a liquid, and by open pouring if it is the powder form. It is added at a point where thorough mixing will take place.
Certified pharmaceutical secondary standards for application in quality control provide pharma laboratories and manufacturers with a convenient and cost-effective alternative to pharmacopeia primary standards. Zinc Pyrithione is used for controlling a variety of fungal infections. It is used commercially in personal care products, including antidandruff shampoos and skin creams.
These Secondary Standards are qualified as Certified Reference Materials. These are suitable for use in several analytical applications including but not limited to pharma release testing, pharma method development for qualitative and quantitative analyses, food and beverage quality control testing, and other calibration requirements.
These secondary standards offer multi-traceability to the USP, EP and BP primary standards, where they are available.
This Certified Reference Material (CRM) is produced and certified in accordance with ISO 17034 and ISO/IEC 17025. All information regarding the use of this CRM can be found on the certificate of analysis.
To see an example of a Certificate of Analysis for this material enter LRAB3707 in the slot below. This is an example certificate only and may not be the lot that you receive.
Medical Definition of zinc pyrithione: an antibacterial and antifungal compound C10H8N2O2S2Zn that is nearly insoluble in water, possesses cytostatic activity against epidermal cells, and is the active ingredient in various shampoos used to control dandruff and seborrheic dermatitis
Zinc Pyrithione occurs as white to slightly yellow crystals. In cosmetics and personal care products, Zinc Pyrithione is used in the formulation of cleansing products, hair conditioners, shampoos, eyeliners, face powders and skin care products.
Zinc Pyrithione enhances the appearance and feel of hair, by increasing hair body, suppleness, or sheen, or by improving the texture of hair that has been damaged physically or by chemical treatment. It also helps to control dandruff, seborrheic dermatitis, and psoriasis. Zinc Pyrithione cleanses the skin or prevents odor by destroying or inhibiting the growth of microorganisms. It can also be used to protect cosmetics and personal care products from spoilage by preventing or retarding bacterial growth. Follow this link for more information about how preservatives protect cosmetics and personal care products.
Zinc pyrithione (ZPT) is the active ingredient most commonly used in many antidandruff treatments. Despite decades of successful use to treat human scalps, little is understood about the antifungal mechanism of action of ZPT.
Structure of the compound
The pyrithione ligands, which are formally monoanions, are chelated to Zn2+ via oxygen and sulfur centers.
In the crystalline state, zinc pyrithione exists as a centrosymmetric dimer, where each zinc is bonded to two sulfur and three oxygen centers.
In solution, however, the dimers dissociate via scission of one Zn-O bond.
Zinc pyrithione (INCI name)
Bis [1-hydroxy-2(1 H)-pyridinethionato-O,S] (T-4) zinc (IUPAC)
Bis (N-oxopyridine-2-thionato) zinc (II)
ZP, ZnPT, ZnPTO, BOTZ
Trade names and abbreviations
Zinc pyrithione is an antibacterial and antifungal that is found mainly in anti-dandruff shampoos. It is particularly adapted to fight against Malessezia, a fungus naturally present on the skin, but responsible for dandruff of the scalp.
Its functions (INCI)
Anti dandruff : Helps fight against dandruff
Antiseborrhoeic : Helps control sebum production
Hair conditioning : Leaves hair easy to comb, soft, soft and shiny and / or confers volume, lightness and shine
Preservative : Inhibits the development of microorganisms in cosmetic products.
Zinc Omadine Fine Particle Size (FPS) Fungicide-Algaecide Dispersion (zinc pyrithione)
Zinc Omadine 48% Aqueous Dispersion FPS (Fine Particle Size) offers bactericide-fungicide efficacy in shampoos, conditioners and leave-on products.
Zinc Omadine products are highly active, broad spectrum antimicrobial agents that are registered around the world for use in both personal care as well as industrial product applications.
Scientific Committee on Consumer Safety issued opinion on Zinc Pyrithione
The cosmetic ingredient Zinc Pyrithione (ZPT) is frequently used in the formulation of hair conditioners, shampoos, face powders, cleansing products, eyeliners and skin care products.
On the 4th March 2020, the Scientific Committee on Consumer Safety concluded that Zinc Pyrithione is safe when used as an anti-dandruff in rinse-off hair products in a concentration of maximum 1%.
ZPT is currently regulated as a preservative in rinse-off products (with the exception of oral hygiene products) in a concentration of up to 0.5% in general products and up to 1.0% in hair products (Annex V/8). Moreover, Zinc Pyrithione is also allowed in a concentration up to 0.1% in leave-on hair products (Annex III/101).
Being subject to several safety evaluations, Zinc Pyrithione was previously found safe as an anti-dandruff agent in rinse-off hair care products at a maximum concentration of 2.0%. This came as a result of a safety dossier that was submitted by Cosmetics Europe to demonstrate the safety of ZPT as anti-dandruff in rinse-off hair products.
However, the new restriction of 1% was given according to the conditions laid out in Article 15(d) (i.e. ‘overall exposure from other sources’) of the Regulation (EC) No 1223/2009 and the currently existing scientific data.
This compound was first described in the 1930s.
Pyrithione zinc, also commonly known as zinc pyrithione, has antibacterial, antimicrobial, and antifungal properties that can help treat seborrheic dermatitis (also called dandruff), scalp psoriasis, and acne.
It can inhibit the growth of yeast, which is a main factor in dandruff.
As the name suggests, pyrithione zinc is derived from the chemical element zinc and it’s used in a variety of hair and skin care products.
Pyrithione is the conjugate base derived from 2-mercaptopyridine-N-oxide (CAS# 1121-31-9), a derivative of pyridine-N-oxide.
Zinc pyrithione can be used to treat dandruff and seborrhoeic dermatitis.
It also has antibacterial properties and is effective against many pathogens from the Streptococcus and Staphylococcus genera.
Its other medical applications include treatments of psoriasis, eczema, ringworm, fungus, athletes foot, dry skin, atopic dermatitis, tinea versicolor, and vitiligo.
Because of its low solubility in water (8 ppm at neutral pH), zinc pyrithione is suitable for use in outdoor paints and other products that protect against mildew and algae.
It is an algaecide. It is chemically incompatible with paints relying on metal carboxylate curing agents.
When it is used in latex paints with water containing much iron, a sequestering agent that preferentially binds the iron ions is needed.
It is decomposed by ultraviolet light slowly, providing years of protection in direct sunlight.
Zinc pyrithione is an antibacterial treatment for household sponges, as by the 3M Corporation.
A process to apply zinc pyrithione to cotton with washable results was patented in the United States in 1984.
Zinc pyrithione is used to prevent microbe growth in polyester.
Textiles with applied zinc pyrithione protect against odor-causing microorganisms. Export of antimicrobial textiles reached US$497.4 million in 2015.
Mechanism of action
Its antifungal effect is thought to derive from its ability to disrupt membrane transport by blocking the proton pump that energizes the transport mechanism.
Zinc pyrithione is approved for over-the-counter topical use in the United States as a treatment for dandruff and is the active ingredient in several antidandruff shampoos and body wash gels.
In its industrial forms and strengths, it may be harmful by contact or ingestion.
Zinc pyrithione can trigger a variety of responses, such as DNA damage in skin cells.
Ketoconazole, another antifungal agent used in shampoos
Piroctone olamine, another antifungal agent used in shampoos
Selenium disulfide, an active ingredient used in shampoos such as Selsun Blue
Zinc pyrithione shampoo
Zinc pyrithione shampoo is found in many common anti-dandruff shampoos. It is antifungal, antibacterial, and antimicrobialTrusted Source, meaning it can kill fungus, bacteria, and microorganisms that can contribute to an itchy, flaky scalp.
To use, follow the instructions on the bottle, but generally you should:
Apply to wet scalp.
Work into a lather.
Let it sit on your scalp for a minute.
Zinc pyrithione cream
Seborrheic dermatitis often affects the scalp, but it can also cause rough, scaly patches on the skin. Zinc pyrithione cream is used to treat seborrheic dermatitis or psoriasisTrusted Source on the body.
For the treatment of mild seborrheic dermatitis, the National Eczema Foundation suggests daily use of a cleanser that contains 2 percent zinc pyrithione followed by a moisturizer. You can also use the cream daily by applying it in a thin layer to the affected area.
Buy zinc pyrithione cream online.
Zinc pyrithione face wash
Zinc pyrithione face wash can help alleviate redness and itching associated with seborrheic dermatitis on the face. It can also help alleviate some of the greasiness associated with eczema and seborrheic dermatitis.
There’s some evidence that using a medicated soap that contains 2 percent zinc pyrithioneTrusted Source may help clear acne.
Buy zinc pyrithione face wash online.
Potential side effects of zinc pyrithione
Zinc pyrithione is approved for over-the-counter (OTC) dandruff shampoo, but it should only be used topically.
It may burn or sting if it gets in the eyes, mouth, or nose.
Other side effects may include burning or redness, and in rare cases, blistering.
Talk to a doctor if you’re pregnant or nursing before using zinc pyrithione. If you swallow zinc pyrithione, consult a doctor right away.
Pyrithione zinc vs. selenium sulfide
Selenium sulfide is a topical antifungal treatment that slows the growth of yeast on the scalp or body.
It’s available in both prescription and OTC forms.
Like pyrithione zinc, it’s also commonly foundTrusted Source in anti-dandruff shampoos, and the two ingredients can complement each other. Selenium sulfide is known to be a bit stronger and can be irritating if left on the scalp for too long.
It’s naturally a light orange color, so shampoos or skin care products containing selenium sulfide are usually a peachy hue.
Pyrithione zinc, which is also known as zinc pyrithione, is a common ingredient in anti-dandruff shampoos, but it can also be effective at treating psoriasis, eczema, and acne. This is because of its antimicrobial, antibacterial, and antifungal properties.
It’s meant for topical use only, and may cause burning or stinging if it comes into contact with your eyes, nose, or mouth.
It should never be ingested. If you’re pregnant, nursing, or thinking of using a product that contains pyrithione zinc on a child, speak with a doctor before doing so.
The effects of a shampoo containing zinc pyrithione on the control of dandruff
R Marks, A D Pearse, A P Walker
• PMID: 3158327
• DOI: 10.1111/j.1365-2133.1985.tb02314.x
Thirty-two subjects who suffered from dandruff participated in a study in which one-half of the head was washed with a shampoo containing 1% zinc pyrithione (ZPT) and the other half was washed with the same shampoo without ZPT.
Four groups, eight subjects per group, were shampooed one, three, six or nine times (shampoo frequency twice per week).
Clinical dandruff gradings of each half of the head were made 4 days after the last shampoo in each group, when scalp biopsy samples were also taken from each half of the head. Measurements of labelling index (LI), mean epidermal thickness (MET), and assessment of the numbers of PAS- and Gram-positive micro-organisms were made on the biopsy samples.
There was a progressive reduction in dandruff on the sides of the head treated with the ZPT shampoo, the differences relative to the placebo-treated areas being statistically significant after three, six and nine washes.
There were no significant differences in LI between treatment groups and the MET was shown to vary according to the treatment and the number of washes.
There was a significant reduction in the number of PAS-positive micro-organisms (but not Gram-positive micro-organisms) on the ZPT-treated areas.
Zinc pyrithione (ZPT) (CAS 13463-41-7; EU 236-671-3) with the chemical name: Bis[(2- pyridyl-1-oxo)-thio]zinc was introduced into the Cosmetics Directive as a preservative by Directive 82/368/EEC. It was authorised as a preservative at the maximum concentration of 0.5% with the limitation "Authorized in products rinsed off after use, forbidden in products for oral hygiene".
Back in 1984 (17/12/1984) the Scientific Committee on Cosmetology (SCC) concluded in its opinion XI/389/84 concerning the use of pyrithione zinc in hair-care preparations not rinsed off after use: "The Committee notes that the use of pyrithione zinc is allowed as a preservative in products rinsed off after use at a maximum concentration of 0.5% in the finished product.
The Committee finds that the substance is highly toxic, and cannot agree recommending any extension of its use unless percutaneous absorption in man can be shown not to occur in normal skin, nor under conditions of inflammation or abrasion."
Submission I for Zinc pyrithione was submitted in July 2000 by COLIPA 1.
The Scientific Committee on Cosmetic Products and Non-Food Products intended for Consumers (SCCNFP) adopted its opinion (SCCNFP/0671/03) on 17th December 2002 with the conclusion: “The SCCNFP is of the opinion that zinc pyrithione does not pose a health risk when used:
• for non-preservative purposes in cosmetic rinse-off and leave-on hair care products at a maximum concentration of 1.0 % and 0.1 %, respectively; or,
• for preservative purposes in cosmetic rinse-off hair care products at a maximum concentration of 1.0 %. Zinc pyrithione should not be used in products for oral hygiene.”
Zinc pyrithione is currently regulated as a preservative in rinse-off products (excluding oral hygiene products) in a concentration up to 0.5% in general and up to 1.0% in hair products (Annex VI/1, 8).
Furthermore zinc pyrithione is also allowed in a concentration up to 0.1% in leave-on hair products (Annex III/1, 101).
In the present submission by COLIPA (submission II), which is a supplemental dossier to submission I, the applicant applies for an extension of the authorised concentration from 1.0% to 2.0% in rinse-off antidandruff hair care products.
ZINC PYRITHIONE is classified as :
CAS Number 13463-41-7
EINECS/ELINCS No: 236-671-3
Restriction (applies to EU only): III/101 VI/8
COSING REF No: 38974
INN Name: pyrithione zinc
Chem/IUPAC Name: Pyridine-2-thiol-1-oxide, zinc complex (2:1)
Cosmetic rinse-off products containing Zinc Pyrithione are considered safe, when this ingredient is used as an anti-dandruff at a maximum concentration of 1%.
Zinc is a trace mineral and is vital to the human body and all forms of life, having catalytic, structural and regulatory functions. On the other hand, high levels of dietary zinc can cause anemia, decreased levels of copper and iron absorption and reduction of enzyme activities in several tissues. In 2003, the Scientific Committee on Food established a tolerable total uptake level (UL) of Zinc up to 25 mg. [1,2]
In the cosmetic industry, Zinc and zinc salts are used in a variety of categories.
Cosmetic products might account for maximum 10% of the UL. One of the most widely used zinc salt is Zinc Pyrithione.
It is an aromatic zinc compound used as an antidandruff, antiseborrhoeic, hair conditioning agent and preservative in cosmetics and personal care products. In the European Union (EU), Zinc Pyrithione is included in the Annex III of the European Cosmetic Regulation No. 1223/2009, which means its use is subject to the restrictions laid down. According to this Regulation, Zinc Pyrithione is also included in the Annex V (list of preservatives allowed in cosmetic products), and may be used as a preservative in rinse-off products (excluding oral hygiene products) in a concentration up to 0.5% in general and up to 1.0% in leave-on hair products (Annex V/8). This compound has been used for more than 60 years as an anti-dandruff agent, in concentration up to 1-2%. The U.S. Food and Drug Administration (FDA) allows the use of Zinc Pyrithione as an active ingredient in Over-The-Counter (OTC) dandruff and seborrheic dermatitis drug products.
The European Scientific Committee on Consumer Safety (SCCS) has issued an opinion (March 2020) regarding the safety of Zinc Pyrithione (ZPT) in cosmetic products. The SCCS concluded that Zinc Pyrithione was “safe when used as an anti-dandruff in rinse-off hair products up to a maximum concentration of 1%”. This opinion updated previous SCCS opinions, that stated that this ingredient was safe up to 2% as an antidandruff agent in rinse-off products. [3,4]
In 2018, ECHA’s Risk Assessment Committee (RAC) issued an opinion proposing harmonized classification and labelling at EU level of Zinc Pyrithione as a CMR 1B substance under Regulation (EC) No. 1272/2008 (presumed human carcinogen, mutagen or reproductive toxicant based on animal studies). According to this Regulation, the use of this type of substances shall be prohibited in cosmetic products, unless, by way of exception, specific conditions are fulfilled. 
Zinc Pyrithione was at least a mild skin irritant to human volunteers and it was a severe eye irritant in animal studies. This compound was not a skin sensitizer when tested in guinea pigs and it demonstrated a low potential to induce contact hypersensitivity in humans, when tested alone or in cosmetic formulations. Zinc Pyrithione is neither genotoxic nor mutagenic in vivo and in vitro. It showed no evidence of carcinogenic potential in chronic oral and dermal studies
Very low solubility in most solvents
Water: 0.0015 w/w %
Ethanol: 0.031 w/w %
Acetone: 0.07 w/w %
Chloroform: 0.34 w/w %
Mineral oil, light: 0.0001 w/w %
Water solubility at 20°C, reported at ECHA Website: 4.93 mg/L (EU Method A.6), 6.3 ppm (OECD 105)
Function and uses Zinc pyrithione (ZPT) is currently regulated as a preservative in rinse-off products (excluding oral hygiene products) in a concentration up to 0.5% in general and up to 1.0% in hair products (Annex VI/1, 8).
Furthermore zinc pyrithione is also allowed in a concentration up to 0.1% in leave-on hair products (Annex III/1, 101).
In the present submission, the applicant applies for an extension of the authorised concentration from 1.0% to 2.0% in rinse-off antidandruff hair care products.
According to the EC Commission Regulation (No. 1451/2007), Zink pyrithione is also used as a biocide in biocidal product categories 2, 6, 7, 9, 10, 11, 12 and 22 of Annex V of the EU Biocide Directive (Directive 98/8/EC).
Understanding the Mechanism of Action of the Anti-Dandruff Agent Zinc Pyrithione against Malassezia restricta
Minji Park, Yong-Joon Cho, Yang Won Lee & Won Hee Jung
Dandruff is known to be associated with Malassezia restricta. Zinc pyrithione (ZPT) has been used as an ingredient in anti-dandruff treatments. The mechanism of ZPT has been investigated in several studies; however, a non-pathogenic model yeast, such as Saccharomyces cerevisiae was most often used. The aim of the present study was to understand how ZPT inhibits the growth of M. restricta. We analyzed the cellular metal content and transcriptome profile of ZPT-treated M. restricta cells and found that ZPT treatment dramatically increased cellular zinc levels, along with a small increase in cellular copper levels. Moreover, our transcriptome analysis showed that ZPT inhibits Fe-S cluster synthesis in M. restricta. We also observed that ZPT treatment significantly reduced the expression of lipases, whose activities contribute to the survival and virulence of M. restricta on human skin. Therefore, the results of our study suggest that at least three inhibitory mechanisms are associated with the action of ZPT against M. restricta: (i) an increase in cellular zinc levels, (ii) inhibition of mitochondrial function, and (iii) a decrease in lipase expression.
Dandruff is a common scalp condition associated with abnormal scalp flaking. Half of the adult human population is affected by the condition at some time in their lives1. In general, dandruff is ascribed to three etiological factors, Malassezia yeast, sebaceous secretions, and individual susceptibility2. Among these, Malassezia yeast has long been considered the main cause of dandruff; this idea is supported by improvement in dandruff, accompanied by a reduction in the number of the yeast cells on the scalp, following treatment with a shampoo containing an antifungal agent3,4,5. A total of 17 different Malassezia species have been identified, and, among them, M. restricta is the dominant species on human skin6,7,8,9,10. Moreover, recent large-scale sequencing analyses have indicated increased presence of M. restricta on scalps with dandruff compared to that on healthy scalps, suggesting an association between the fungus and dandruff 8,11,12. The studies have suggested that lipases secreted from Malassezia contribute to the development of dandruff and led to the hypothesis that these enzymes hydrolyze sebum triglycerides and help the yeast cells take up saturated fatty acids to generate energy. The accumulation of excess unsaturated fatty acids, such as oleic acid, on the skin causes skin irritation in patients suffering from dandruff2,13.
Zinc pyrithione is a derivative of pyrithione (1-hydroxy-2-pyridinethione), which is synthesized from the antimicrobial metabolite ‘aspergillic acid’ of Aspergillus flavus14,15,16,17. A number of shampoos and rinse-off products containing 0.3–2% ZPT have been used extensively over the counter to treat dandruff18. Although the use of ZPT as an antidandruff agent is widespread, its mechanism of action against Malassezia, and M. restricta in particular, is still unclear; only physiological observations of Malassezia growth inhibition by ZPT have been reported19,20. The mechanism of action of ZPT has been characterized using different model fungal organisms, rather than M. restricta. Ermolayeva and Sanders21 used Neurospora crassa and suggested that ZPT leads to membrane depolarization either directly or indirectly, thereby, inhibiting proton pump-mediated membrane transport. They suggested that this inhibition might be caused solely by pyrithione, because zinc salt is believed to dissociate after ZPT is transported into the cytosol, and that pyrithione alone acted in this manner21,22. However, membrane depolarization occurs at a significantly higher concentration of pyrithione, which is beyond the inhibitory concentration for the fungi23; therefore, it is difficult to assert that the mechanism of action of ZPT on fungi involves membrane depolarization.
Yasokawa et al.24 analyzed the transcriptome of Saccharomyces cerevisiae cells treated with ZPT and found that the compound upregulates the expression of genes required for iron transport. These results suggested that ZPT induces iron starvation in the yeast cells. Furthermore, they observed that the addition of iron restored the growth of S. cerevisiae cells in medium containing ZPT, supporting the idea that the compound induces iron deficiency in the yeast. In contrast, another study by Reeder et al.25 showed that iron levels in ZPT-treated S. cerevisiae cells were not changed, although they observed an upregulation of expression of Fet3, a ferroxidase in the high-affinity reductive iron transport system, which suggested that iron starvation might not be a direct cause of ZPT toxicity. Instead, Reeder et al.25 found that cellular copper levels were increased on ZPT treatment and observed a downregulation of CTR1, a high-affinity copper transporter in the plasma membrane. To confirm that increased cellular copper levels are one of the main causes of growth inhibition by ZPT, a S. cerevisiae haploid gene deletion library was screened against ZPT. Deletion mutants that were growth inhibited upon ZPT treatment included a mutant lacking ACE1, which encodes a transcription factor responsible for detoxification of high cellular copper levels, a finding of which supports the idea that ZPT treatment causes copper toxicity in yeast cells. Moreover, a number of deletion mutants that lack genes involved in iron-sulfur cluster (Fe-S) assembly in mitochondria showed significant growth defects following ZPT treatment. These results suggested that, in addition to copper toxicity, copper-mediated inactivation of Fe-S cluster assembly in mitochondria also contributes to growth inhibition by ZPT, at least in S. cerevisiae.
Although previous studies have suggested possible mechanisms of action of ZPT against model fungal organisms, they have not clearly explained how ZPT inhibits the growth of Malassezia, which is phylogenetically distant. Therefore, in this study, we attempted to understand the mechanism of action of ZPT against M. restricta, using biochemical and transcriptome analyses and found that ZPT mainly triggered zinc toxicity and mitochondrial dysfunction. Furthermore, our data suggested that ZPT decreases expression of lipases, which may play an important role in survival of the M. restricta on the surfaces of scalps of patients with dandruff13,26,27. To our knowledge, this is the first comprehensive study to directly investigate the mechanism of action of ZPT against M. restricta.
ZPT treatment led to an increase in cellular zinc levels in M. restricta
ZPT is a well-known zinc ionophore that has antifungal activity, and several studies using model fungi have indicated that alteration of cellular metal content is one of the main antifungal mechanisms of action of the compound. Examples include an increase in cellular copper levels in ZPT-treated S. cerevisiae, as mentioned previously. We, therefore, investigated how ZPT treatment altered cellular levels of essential metals, such as copper, zinc, manganese, and iron. The metal content of ZPT-treated S. cerevisiae cells was measured in parallel with inductively coupled plasma-atomic emission spectroscopy (ICP-AES) to replicate data previously reported by Reeder et al.25. The results were similar to what was previously observed (see Supplementary Table S1), confirming that ZPT increases cellular copper levels in S. cerevisiae. Furthermore, the results indicated that our method to determine cellular metal levels was reliable.
Subsequently, cellular levels of essential metals in M. restricta cells grown in the presence of ZPT were determined by the same method used to investigate whether ZPT altered cellular metal levels in the fungus, and the results showed that, among the essential metals, cellular zinc levels were significantly and dose-dependently increased in cells grown in the presence of ZPT. However, unlike S. cerevisiae, only a small increase in copper levels was observed in cells grown in the presence of ZPT compared to that in cells grown in the absence of the compound, and no change in iron or manganese levels was detected (Fig. 1). These data suggest that the mechanism by which ZPT affects the metal content in M. restricta is different from that in S. cerevisiae, and that ZPT mainly increased zinc levels along with small increase of copper levels in M. restricta cells, unlike what was observed in S. cerevisiae cells.
Children with seborrheic dermatitis
If the child has seborrheic dermatitis and curly thick hair, even blond or red, there is a difficulty in applying a medical shampoo. Zinc pyrithione is the most acceptable antidandruff substance for curly hair, because it leads to less drying and stiffness. Avoid ketoconazole shampoo because it causes more friction between the fibers. Sometimes increasing the frequency of shampooing is enough to treat scalp desquamation, even with a regular product. If a medicated shampoo is needed, alternating regiments may be tried first: 1 day with zinc pyrithione and the next day with regular shampoo. It is necessary to apply a conditioner in both situations and rinse it thoroughly. In some countries, scalp solutions with zinc or salicylic acid are available and may be applied as a seborrheic dermatitis treatment instead of a shampoo. When corticosteroids are needed, lotions or creams are better choices than alcoholic solutions vehicles. Avoid conditioning shampoos for those who present with seborrheic dermatitis. The use of astringents or dry shampoos is popular in some countries and may be an option for those who wear hair locks or braids for long periods.
Although many curly and thick-hair individuals believe that their dry hair is caused by frequent shampooing, it actually may be due to inappropriate use of hair care products and regimens that are not ideal for their hair type. Cleansing with a shampoo that eliminates residues is recommended every 15 days for those who use leave-in products or heavy conditioners, even children.
Anti-dandruff agents are intended to reduce the formation of dandruff flakes. The cause for dandruff is not fully understood but the treatment involves the use of a number of “actives” that function either as antimicrobial agents or as anti-mitotic agents. The choice of “active” depends on the regulatory requirements in the markets that are being served. In the United States, there are five ingredients that are currently approved for use in over the counter (OTC) anti-dandruff products. The two most popular ingredients are zinc pyrithione and selinium sulfide. The other approved “actives” are salicylic acid, sulfur, and coal-tar solution. With the exception of coal tar and salicylic acid, the other three ingredients are used as suspensions in shampoo formulations. In the case of zinc pyrithione, the most popular anti-dandruff active used in the United States, it is supplied as 48% dispersion in water. It is most commonly used at 1.0% active in a shampoo formulation.
When using either selinium sulfide (used at 1.0%) or zinc pyrithione (used at 0.3–2.0%) a suspending agent such as acrylates; C10–30 alkyl acrylates crosspolymer or magnesium aluminum silicate is also needed to keep the “active” uniformly suspended in the shampoo. Since both of these “actives” are insoluble, shampoos that contain them will be opaque. Opacifying agents such as ethylene glycol monostearate (EGMS) or ethylene glycol distearate (EGDS) are frequently used to give the shampoo an attractive opaque/pearlescent appearance instead of a flat “paint” appearance.
Zinc Pyrithione Inhibits Yeast Growth through Copper Influx and Inactivation of Iron-Sulfur Proteins
Zinc pyrithione (ZPT) is an antimicrobial material with widespread use in antidandruff shampoos and antifouling paints.
Despite decades of commercial use, there is little understanding of its antimicrobial mechanism of action.
We used a combination of genome-wide approaches (yeast deletion mutants and microarrays) and traditional methods (gene constructs and atomic emission) to characterize the activity of ZPT against a model yeast, Saccharomyces cerevisiae.
ZPT acts through an increase in cellular copper levels that leads to loss of activity of iron-sulfur cluster-containing proteins.
ZPT was also found to mediate growth inhibition through an increase in copper in the scalp fungus Malassezia globosa. A model is presented in which pyrithione acts as a copper ionophore, enabling copper to enter cells and distribute across intracellular membranes. This is the first report of a metal-ligand complex that inhibits fungal growth by increasing the cellular level of a different metal.
Fungi have an essential role in causing dandruff, a scalp disease affecting >40% of the world's adult population.
Zinc pyrithione (ZPT) is an antimicrobial compound that has been used since the 1960s in antidandruff shampoos and in antifouling paints.
In dandruff subjects, ZPT treatment reduces the amount of fungus on the scalp and stops dandruff flaking.
Despite billions of human scalp treatments for over 4 decades, little is known of the mechanism by which ZPT inhibits fungal growth.
Malassezia globosa and M. restricta are the two most common fungi on scalp.
Despite a recent description of the genome sequences of these two species, study of Malassezia is challenging due to the absence of transformation methods and available mutants. Several attempts have been made to characterize the mode of action of ZPT against model fungi.
ZPT has been reported to inhibit transport by membrane depolarization.
However, efficacy was reported only with doses of at least 100 μM, whereas microbial growth inhibition is observed at much lower ZPT doses.
Pyrithione is a well-known zinc ionophore that causes increased zinc levels within mammalian cells.
High intracellular zinc levels can inhibit microbial growth, likely due to zinc binding to intracellular proteins and resulting in mismetallation.
Yasokawa et al. recently used transcriptional analysis of ZPT-treated Saccharomyces cerevisiae to suggest that ZPT causes iron starvation. They further showed that an iron salt lowered the antiyeast activity of ZPT, suggesting that iron starvation is a key component of ZPT's mechanism of action.
In this communication, we confirm the observation by Yasokawa et al. that ZPT increases transcription of the iron regulon: however, we ascribe that increase not to a transcriptional response to low iron concentrations but rather to a decrease in the activity of iron-sulfur (Fe-S) cluster-containing proteins.
We show that ZPT-mediated growth inhibition is due to increased copper uptake and that copper inactivates key Fe-S proteins by a mechanism similar to that described for copper-mediated growth inhibition in bacteria.
Further, we show that ZPT incubation with the scalp fungus M. globosa also leads to a copper imbalance, suggesting that increased intracellular copper is the source of ZPT efficacy against the fungi associated with dandruff.
Zinc pyrithione 48
1. Zinc pyrithione 48 is high-efficiency, environmental protection, hypotoxicity and broad-spectrum.
2. Pyrithione zinc is mixture in water of very fine particles of zinc pyrithione, a dispersant, and a viscosity control agent.
3. Exhibits pronounced growth inhibiting activity against a broad spectrum of both Gram positive and Gram negative bacteria in cosmetic preparations.
4. ZPT 48 inhibits the growth of fungi, both yeast and mold, in cosmetic preparations.
Sodium Pyrithione powder
1. Sodium pyrithione is the most effective water-soluble industrial mildew preservative, with high efficiency, broad spectrum, low toxicity and stability.
2. SPT 98 has good antiseptic and mould proofing effects, it can restrain and sterilize eight moulds, including black mold,aspergillus flavus, aspergillus versicolor,penicillium citrinum, paecilomium varioti bainier,trichoderma viride,chaetomium globasum and cladosporium herbarum.
3. Sodium Omadine is high purity and stable quality;
4. Free sample could be deliveried for test before bulk order quantity.
Raw Material Zinc Pyrithione
1. Zinc Pyrithione is a coordination complex of zinc, with hihg purity of 98% min.
2. ZPT is fine, broad-spectrum and environment-friendly antiseptics, It can inhibit the growth of Gram-positive, negative bacteria and mold.
Zinc pyrithione was already synthesized and used as a topical antifungal or antibacterial agent.
3. ZPT has a strong killing power on fungi and bacteria, it can effectively kill dandruff fungus,playing a role in dandruff. Widely used in used in daily chemicals, shampoo.
4. The mixture of ZPT and Cu2O also can be used as marine antifouling coating to prevent adhering of shells, seaweeds and aquatic organisms to hulls.
Zinc Pyrithione (ZnPT) as an Antifouling Biocide in the Marine Environment—a Literature Review of Its Toxicity, Environmental Fates, and Analytical Methods
Zhi Yang Soon, Jee-Hyun Jung, Mi Jang, Jung-Hoon Kang, Min-Chul Jang, Jae-Seong Lee & Moonkoo Kim
Since the ban of tributyltin in antifouling paints, many alternative biocides have been introduced to prevent settlement and growth of marine organisms on ship hulls.
Zinc pyrithione (ZnPT) is one of the most frequently used alternative biocides in antifouling paints.
This paper reviewed the overall chemical properties, toxicological characteristics, and environmental fates of ZnPT, as well as the analytical challenges of studying pertinent processes.
ZnPT is generally toxic to a wide range of marine organisms, including algae, bivalves, sea urchins, polychaetes, crustaceans, and fish, typically at μg/L levels.
ZnPT can be transchelated into other compounds in the presence of metal ions, and photodegrades when exposed to UV light.
ZnPT is also reported to be biodegraded or hydrolyzed forming several metabolites of their own toxicity and stability.
However, ZnPT accumulates in the water column or sediment, if it does not degrade at certain environmental conditions.
To determine potential risks caused by ZnPT in the marine environment, studies have evaluated the environmental distribution of ZnPT with various chromatographic or voltammetry methods.
Unfortunately, rapid transchelation and degradation of ZnPT in both the marine environment and laboratory interfered with most of the methods employed, making it difficult to evaluate its environmental distribution.
More robust and sensitive analytical methods need to be developed to reliably describe the environmental release and distribution of ZnPT.
To comprehensively understand the risk posed by the input of ZnPT into the marine environment, total degradation processes and its potential products also need to be adequately addressed.
The antifungal mechanism of action of zinc pyrithione
October 2011British Journal of Dermatology 165 Suppl 2(suppl. 2):9-12
Zinc pyrithione (ZPT) is the active ingredient most commonly used in many antidandruff treatments.
Despite decades of successful use to treat human scalps, little is understood about the antifungal mechanism of action of ZPT.
The objective of this study is to understand the molecular mechanism by which ZPT inhibits fungal growth, the underlying basis for its therapeutic activity.
Modern systems biology approaches, such as deletion library screening and microarray analysis, were used in combination with traditional measures of metal content, microbial growth and enzyme assays.
It was shown that ZPT inhibits fungal growth through increased cellular levels of copper, damaging iron-sulphur clusters of proteins essential for fungal metabolism.
The molecular basis for the antifungal activity of the commonly used active ZPT has been elucidated, more than 50 years since its introduction, as utilizing a copper toxicity mechanism that targets critical iron-sulphur proteins.
Zinc pyrithione has a broad antimicrobial spectrum of efficacy against various microorganisms such as bacteria, fungi, algae and indirectly against dust mites.
The outstanding properties of zinc pyrithione with regard to effectiveness and compatibility are also used in cosmetic products.
Active ingredient: Zinc pyrithione
Most Sanitized zinc pyrithione products are approved for OEKO-TEX standard 100, classes I-IV.
Outstanding durability and effectiveness
Broad spectrum of efficacy against bacteria, fungi and dust mites
Long-lasting material protection, e.g., against rotting
High wash resistance
Ease of application in the usual application processes
Readily combined with many textile effects, e.g., fluorocarbons
Can be added to a dye bath
Zinc pyrithione is the pyrithione complexes of zinc bromide, in the early 1930s, was already synthesized and used as a topical antifungal or antibacterial agent.
At room temperature it is white to yellow crystalline powder. Slight characteristic odor. Insoluble in water.
Solubility: water 15mg/kg; pH = 8 Water 35mg/kg; Ethanol 100mg/kg; polyethylene glycol (PEG400) 2000mg/kg.
A pH optimum range of 4.5 to 9.5; mass fraction of 10% suspension pH3.6.
Zinc pyrithione react with cationic and non-ionic surfactants forming insoluble precipitate, unstable in the light and oxidizer, when at higher temperatures ,it is not stable to acids and bases .
It is not compatible with EDTA, non-ionic surfactants make it partially deactivated.
When with the presence of heavy metals, chelation or anti-sequestration will occur, and these chelates are insoluble in water.
EEC and GB7916-87 provide that maximum allowable concentration of mass fraction of zinc pyrithione on cosmetics is 0.5%, only for cleaning after using products.
General concentration 250~1000mg/kg (active), zinc pyrithione can be used in gels, creams, lotions, talcum powder and anti-dandruff shampoo, deodorant and also for disinfecting articles.
Shampoo for dandruff,zinc pyrithione can inhibit Gram positive and negative bacteria and mold growth,Care hair Effectively , delay hair aging ,control white hair and hair loss generation. zinc pyrithion is also used as a cosmetic preservative, oil, paint biocide.
Zinc pyrithione has a strong killing power on fungi and bacteria so that it can effectively kill dandruff fungus,playing a role in dandruff .
Zinc pyrithione is a regulator of keratinization, selenium sulfide has antimicrobial properties and ketoconazole is an antifungal agent (i.e.can provide the reduction of the lipophilic yeast Malassezia furfur).
Zinc pyrithione shampoos (in concentrations between 1 to 2%) and shampoos with selenium sulide have been reported to be effective in the treatment of scalp psoriasis.
However,their efficacy has not been substantiated by controlled studies.
There is also some evidence that shampoos with antifungal agents (e.g.ketoconazole)can have a beneficial effect on scalp conditions.
It should be noted, however, that the effectiveness of these shampoos is much smaller than these containing tars, corticosteroids or keratolytics.
Zinc pyrithione is very rapidly transformed by photolysis.
Experiments conducted under sterile conditions with a light:dark cycle of 12:12 hours have shown that, under exposure to light, the concentration of [pyridine-2,6-14C]zinc pyrithione in pH 9 buffer was reduced to 33% of the radioactivity added in 15 min.
Data from this study also demonstrated that less than 5% of the 14C added occurred as zinc pyrithione after 1 hour of exposure to light.
Similar results have been achieved when photolysis of zinc pyrithione was investigated by use of artificial seawater.
In this study, the parent compound constituted 45% of the radioactivity added after 15 min while, after 24 hours, 1.3% of the added dose occurred as zinc pyrithione.
The estimated half-lives of the photolytic transformation of zinc pyrithione was 13 min in pH 9 buffer and 17.5 min in artificial seawater (Reynolds 1995a).
The toxicity of the active substance zinc pyrithione has been investigated in standard laboratory tests with a number of aquatic organisms living in fresh water (the green alga Selenastrum capricornutum, the crustacean Daphnia magna, the fish rainbow trout (Oncorhynchus mykiss) and fathead minnow (Pimephales promelas)) and in seawater (the crustacean Mysidopsis bahia, the fish sheepshead minnow (Cyprinodon variegatus) and the oyster (Crassostrea virginica)) (Boeri et al. 1993; 1994a-e; Ward et al. 1994a).
The results show that while zinc pyrithione and omadine disulfide were very toxic to aquatic organisms (L(E)C50 in the order of 3-300 µg/L), omadine sulfonic acid and pyridine sulfonic acid were considerably less toxic (L(E)C50 in the order of >20 mg/L) (Olin 1977).
In a long-term study with fish eggs and larvae, pyridine sulfonic acid gave no effects at a concentration of 0.01 mg/L (Boeri et al. 1999).
Algae were the group of organisms most sensitive to the last two substances.
Uses Zinc pyrithione is directly cytotoxic and has antimicrobial effects.
Zinc pyrithione is found in many shampoos (DHS-Zinc, Head and Shoulders) and should be applied for 5 minutes daily for 2 weeks.
Zinc pyrithione is the active ingredient in several shampoos used to control dandruff and seborrheic dermatitis and is also effective in the therapy of tinea versicolor.
It remains unclear whether the beneficial effects are caused by an antiproliferative or antimicrobial effect or both.
It is substantive to the hair, allowing continued therapeutic effect after washing.
zinc pyrithione is a preservative against bacteria, fungi, and yeast.
It is unstable in light and in the presence of oxidizing agents.
Zinc pyrithione is useful in gels, creams, heavy lotions, and talcum powder.
Reactions may lead to photosensitive eczema and actinic reticuloid syndrome.
Zinc pyrithione is used as antifungal, antibacterial and antiseborrheic agent used in many shampoos and hair creams.
Zinc pyrithione is the active ingredient in several shampoos used to control dandruff and seborrheic dermatitis and is also effective in the therapy of tinea versicolor.
It remains unclear whether the beneficial effects are caused by an antiproliferative or antimicrobial effect or both.
It is substantive to the hair, allowing continued therapeutic effect after washing.
Head & Shoulders Conditioner (Procter & Gamble).
Fine beige granules.
Air & Water Reactions
Insoluble in water.
Organometallics, such as Zinc pyrithione, are reactive with many other groups.
Incompatible with acids and bases.
Organometallics are good reducing agents and therefore incompatible with oxidizing agents.
Often reactive with water to generate toxic or flammable gases.
Flash point data for Zinc pyrithione are not available, but Zinc pyrithione is probably combustible.
Zinc pyrithione is widely used in antidandruff shampoos and is a classic allergen.
Concomitant reactions are expected to both zinc and sodium pyrithione.
Poison by ingestion, skin contact, intraperitoneal, and intravenous routes.
Moderately toxic by subcutaneous route.
An experimental teratogen.
Experimental reproductive effects.
An eye irritant.
When heated to decomposition it emits very toxic fumes of NOx, SOx, and ZnO.
Used as an anti- dandruff agent in shampoos. See also ZINC COMPOUNDS and SULFIDES.
Malassezia restricta and Malassezia globosa are lipid dependent commensal yeasts associated with dandruff.
Antifungal actives such as zinc pyrithione are commonly used in antidandruff shampoos, although their efficacy is not clearly demonstrated.
In this study, we assessed the efficacy of antifungal treatments on scalp Malassezia via a combination of culturomic and genomic detection methods.
Zinc pyrithione inhibited Malassezia growth at low minimum inhibitory concentrations (MICs).
In a longitudinal pilot study, quantitative polymerase chain reaction (qPCR) analysis showed a decrease in M. restricta on the scalp after zinc pyrithione treatment.
These findings validate the antifungal efficacy of zinc pyrithione as a dandruff treatment.
Malassezia yeasts are associated with dandruff and seborrheic dermatitis.
Zinc pyrithione is effective against Malassezia growth in vitro and when tested on human skin as a shampoo.
These findings will be useful for investigating the role of Malassezia in skin microbiome intervention studies.
zinc pyrithione, human skin, Malassezia, quantification, efficacy
Zinc Pyrithione is one of the most widely used active ingredients to treat dandruff caused by Seborrheic Dermatitis on the market today.
A staggering 20% of the shampoos we’ve reviewed contain the ingredient, making it (by the second most widely used active ingredient after salicylic acid in the market today.
There are hundreds of brands out there that contain the ingredient. Everything from Head and Shoulders to generic dollar store dandruff shampoos.
And the quality varies wildly.
In order to find the best zinc pyrithione shampoo on the market today, we spoke to four board-certified dermatologists for their guidance, and have put in literally hundreds of hours worth of research, reviewing over a hundred dandruff shampoos in the process.
EVAFINE P 50
2(1H)-PYRIDINETHIONE, 1-HYDROXY-, ZINC COMPLEX
1-HYDROXY-2-PYRIDINETHIONE, ZINC SALT
2-MERCAPTOPYRIDINE 1-OXIDE ZINC SALT
2-MERCAPTOPYRIDINE-1-OXIDE ZINC SALT
2-PYRIDINETHIOL 1-OXIDE ZINC SALT
2-PYRIDINETHIOL N-OXIDE ZINC SALT
2-PYRIDINETHIOL-1-OXIDE, ZINC SALT
TOMICIDE Z 50
TOMICIDE ZPT 50
ZINC 2-MERCAPTOPYRIDINE N-OXIDE
ZINC 2-PYRIDINETHIOL 1-OXIDE
ZINC, BIS(1-HYDROXY-2(1H)-PYRIDINETHIONATO-O,S)-, (T-4)-
ZINC, BIS(2-PYRIDINYLTHIO)-, N,N'-DIOXIDE
• 2(1H)-Pyridinethione, 1-hydroxy-, zinc complex
• 2-Mercaptopyridine 1-oxide zinc salt
• 2-Pyridinethiol-1-oxide, zinc salt
• Biocut ZP
• Bis(2-pyridylthio)zinc 1,1'-dioxide
• Breck One Dandruff Shampoo
• CCRIS 4894
• Caswell No. 923
• EINECS 236-671-3
• EPA Pesticide Chemical Code 088002
• Evafine P 50
• FSB 8332
• Finecide ZPT
• HSDB 4498
• Head & Shoulders Conditioner
• Head and Shoulders
• Hokucide ZPT
• NSC 290409
• Niccanon SKT
• Omadine Zinc
• Piritionato cincico
• Piritionato cincico [INN-Spanish]
• Pyrithione zinc
• Pyrithione zincique
• Pyrithione zincique [INN-French]
• Pyrithionum zincicum
• Pyrithionum zincicum [INN-Latin]
• Sebulon Shampoo
• Tomicide Z 50
• Tomicide ZPT 50
• Top Brass
• Vancide P
• Vancide ZP
• Wella Crisan
• ZNP Bar
• Zinc – pyrion
• Zinc 1-hydroxy-2-pyridinethione
• Zinc 2-mercaptopyridine N-oxide
• Zinc Omadine
• Zinc PT
• Zinc pyrethion
• Zinc pyridine-2-thiol 1-oxide
• Zinc pyridine-2-thiol-1-oxide
• Zinc pyridinethione
• Zinc pyrithione
• Zinc, bis(1-hydroxy-2(1H)-pyridinethionato)-
• Zinc, bis(2-pyridinylthio)-, N,N'-dioxide
• Zinc, bis(2-pyridylthio)-, 1,1'-dioxide
• Zinc, bis(2-pyridylthio)-, N,N'-dioxide
• Zinci pyrithionum
• Zincon Dandruff Shampoo
• Zn – pyrion
What are some products that may contain zinc pyrithione?
bis(2-pyridylthio)zinc 1,1'-dioxide ChemIDplus
Pyrithione zinc KEGG COMPOUND
zinc pyridinethione ChemIDplus
breck one dandruff shampoo
head and shoulders
2- mercaptopyridine N-oxide zinc salt
2- mercaptopyridine-1-oxide zinc salt
bis[ pyridine-2-thiolato-kappaS 1(oxide-kappaO)]zinc
2- pyridinethiol, 1-oxide, zinc salt (2:1)
bis(2- pyridylthio)zinc 1,1'-dioxide
tomicide ZPT 50
zinc bis(pyridine-2-thiolate 1-oxide)
zinc omadine enhanced CP dispersion
zinc omadine fine particle size (FPS) fungicide-algaecide dispersion (zinc pyrithione)
zinc omadine general fungicide-algaecide dispersion (zinc pyrithione)
zinc pyrithione 48-50 dispersion (cleanbio zinc)
zinc, bis(1-(hydroxy-kappaO)-2(1H)-pyridinethionato-kappaS2)-, (T-4)-
zinc, bis(1-hydroxy-2(1H)-pyridinethionato)- (8CI)
zinc, bis(2-pyridinylthio)-, N,N'-dioxide
zinc, bis(2-pyridylthio)-, 1,1'-dioxide
zinc, bis(2-pyridylthio)-, N,N'-dioxide
zincon dandruff shampoo
Zinc pyrithione is a chemical compound of zinc. It is used as an antifungal and antibacterial agent. Zinc is a metallic element with the atomic number 30. It is found in nature most often as the mineral sphalerite. Though excess zinc in harmful, in smaller amounts it is an essential element for life, as it is a cofactor for over 300 enzymes and is found in just as many transcription factors.
Zinc Pyrithione Market: Segments-
On the basis of grade
On the basis of application
Personal care products
Paint and Coatings
Dandruff on the scalp is characterized by flaking, irritation, itch, redness and dryness. Malassezia spp yeasts are the primary factor in the development of dandruff.
You will find such yeast cells on everybody’s scalp, although it will only cause dandruff in around 50% of people.
Zinc PYRIO (zinc pyrithione) is a highly effective anti-dandruff agent used in shampoos, conditioners and leave-on products.
Zinc PYRION inhibits the growth of fungi (yeasts and moulds), as well as Gram positive and Gram negative bacteria in cosmetic preparations.
Research has shown that Zinc PYRION is not only highly effective in reducing the level of viable yeast cells on the scalp but also works by normalizing scalp stratum corneum morphology.
Zinc pyrithione (ZnPT) is a widely used booster biocide in combination with copper (Cu) in antifouling paints as a substitute for tributyltin.
The co-occurrence of ZnPT and Cu in coastal marine environments is therefore very common, and may pose a higher risk to marine organisms if they can result in synergistic toxicity. This study comprehensively investigated the combined toxicity of ZnPT and Cu, on the marine copepod Tigriopus japonicus,for thefirsttime, based on both 96-h acute toxicity tests using adult copepods and chronic full-life cycle tests (21 d) using nauplii
ZnPT and CuPT are both metal pyrithiones, and were first introduced into the market as antifouling booster biocides in 1990s. ZnPT-basedantifoulingpaintshave beenintensively applied worldwide, especially in Europe and South Korea (Thomas, 1999), and in Japan, where ZnPT and CuPT are the two most frequently used biocides in antifouling products (Okamura and Mieno, 2006). ZnPT can easily transchelate with Cu into CuPT; a partial transchelation of ZnPT into CuPT was detected in seawater with naturally present Cu, and a total transchelation of ZnPT into CuPT was detected when ZnPT was released from Cu-based antifouling paints (Grunnett and Dahllöf, 2005). Thus, the environmental fate and persistence of ZnPT are closely related to those of CuPT in the marine environment. Both ZnPT and CuPT were found to be highly toxic to aquatic autotrophic species (e.g. microalgae and cyanobacteria) and animals (Turley et al., 2000; Bao et al., 2011, 2012). However, up to now there are relatively few data on the toxicity of both metal pyrithiones to aquatic organisms. ZnPT and CuPT were marked as environmentally neutral and non-persistent in the aquatic environment as they can undergo fast photodegradation to form less toxic compounds in seawater under direct sunlight (half-life
Zinc pyrithione is best known for its use in treating dandruff and seborrheic dermatitis. It also has antibacterial properties and is effective against many pathogens from the streptococcus and staphylococcus class. Its other medical applications include treatments of psoriasis, eczema, ringworm, fungus, athletes foot, dry skin, atypical dermatitis, tinea, and vitiligo.
Zinc pyrithione is approved for over-the-counter topical use in the United States as a treatment for dandruff. It is the active ingredient in several anti-dandruff shampoos such as Head & Shoulders. However, in its industrial forms and strengths, it may be harmful by contact or ingestion.
Due to its low solubility in water (8 ppm at neutral pH), zinc pyrithione is suitable for use in outdoor paints and other products that provide protection against mildew and algae. It is an effective algaecide. It is chemically incompatible with paints relying on metal carboxylate curing agents. When used in latex paints and the water contains high amount of iron, a sequestering agent that will preferentially bind the iron ions is needed. Its decomposition by ultraviolet light is slow, providing years of protection even against direct sunlight.
Zinc pyrithione is also used as an antibacterial treatment for household sponges, most notably by the 3M Corporation.
Its antifungal effect most likely lies in the ability of an un-ionized pyrithione molecule to disrupt membrane transport by blocking the proton pump that energizes the transport mechanism. Fungi are capable of inactivating pyrithione in low concentrations.
Zinc pyrithione (ZnPT) is a coordination complex of zinc and has been used widely as an anti-dandruff agent in shampoos. Many shampoos contain both ZnPT and EDTA, a chelating agent speculated to increase ZnPT absorption, thereby raising concerns about neurotoxicity. Here, we investigated the effect of EDTA on ZnPT absorption by direct comparison of ZnPT and pyrithione (PT) concentrations in shampoo formulations, and by pharmacokinetic analysis of ZnPT, PT, and 2-methanesulfonylpyridine (MSP), the main ZnPT metabolite, in rat plasma or urine following exposure to shampoo containing ZnPT alone or a combination of ZnPT and EDTA. Approximately 17.3% of ZnPT was converted to PT by the addition of EDTA in the shampoo formulation. Plasma ZnPT and PT concentrations were not measured up to 24 hr after treatment with shampoo containing 1% ZnPT or 1% ZnPT + 2% EDTA in all rats. However, PT amount in 24-hr urine sample, MSP concentration in plasma, and MSP amount in 24-hr urine sample were approximately 4-, 2.6-, and 2.7-fold higher, respectively, in the 1% ZnPT + 2% EDTA shampoo group than in the 1% ZnPT shampoo group. As confirmed by the formulation analysis and in vivo pharmacokinetic analysis, the exposure of ZnPT could be increased by the absorption of PT due to partial dissociation of ZnPT into PT.
Keywords : Zinc pyrithione, Pyrithione, Pharmacokinetic, Shampoo
Zinc pyrithione (ZnPT) is a coordination complex of zinc (Fig. 1), and its use has been widely allowed in the European Union as an anti-dandruff agent in hair dressing formulations and shampoos, as a preservative at a concentration of 0.5% in cosmetic rinse-off hair-care products, and at a concentration of 1% in rinse-off antidandruff hair-care products (1). It has also been intensively used worldwide as an antifouling agent in painting formulations.
The safety of ZnPT or pyrithione (PT) derivatives, such as sodium pyrithione (NaPT) and copper pyrithione (CuPT), has been studied in several animal species through different routes of administration. Dogs showed ocular damage involving the tapetum lucidum after treatment with oral ZnPT at 6–12 mg/kg/day for 6 days (2,3). Rats and rabbits showed hindlimb weakness or paralysis after subchronic and chronic administration of ZnPT (3,4). ZnPT can transform into CuPT by transchelation with copper ion in both laboratory and natural conditions (5,6). The environmental toxicity of ZnPT or CuPT and their degradation products on microalgae, macrophytes, crustaceans, fish, sea urchin, and other organisms have been studied (7–17). More than 200 shampoos contain both ZnPT and EDTA, a chelating agent. EDTA is useful to improve stability in shampoo formulations. ZnPT has been reported to show low penetration, whereas NaPT, with high water solubility, was shown to be absorbed through the skin in much greater amount than ZnPT (18). Thus, NaPT was prohibited as an ingredient in shampoo formulations. However, the current situation has been left without any criteria with respect to the formulation of ZnPT and EDTA at home and abroad.
These compositions are speculated to increase ZnPT absorption by EDTA, and the resulting toxicity is concerning (Fig. 2). ZnPT is absorbed in small quantities through the skin and is rapidly metabolized into its metabolites. Among the metabolites, 2-methanesulfonylpyridine (MSP) has been identified as a major serum metabolite of ZnPT (19). Thus, in this study, we evaluated the effect of EDTA on systemic ZnPT exposure by measuring ZnPT, PT, and MSP contents in rat plasma and urine following treatment with shampoos containing ZnPT alone or a combination of ZnPT and EDTA.
Zinc pyrithione (ZnPT) has been widely used as an antidandruff agent in hair dressing formulations and shampoos, and as an antifouling agent in painting formulations. The toxicity of ZnPT after oral, dermal, and inhalation administration has been examined in repeated toxicity studies using several animal species. A NOAEL of 500 μg/kg per day obtained from a chronic oral study (SCCS 2014) of ZnPT based on paralysis and hindlimb weakness, has been derived. The percutaneous absorption of ZnPT through the skin is very low with approximately 0.03–3.4%, compared with that of NaPT. Compared with ZnPT, NaPT showed much higher water solubility and is absorbed through the skin in much greater amounts (18). Therefore, NaPT was prohibited as an ingredient in shampoo formulations.
EDTA, a chelating agent, has been used as a component in shampoo formulations to improve stability. We investigated the effect of EDTA on ZnPT absorption in shampoo formulations. PT and MSP, among ZnPT metabolites (19,20), are used as indicators of systemic ZnPT exposure. In this study, a direct LC-MS/MS method was developed for quantitative determination of ZnPT, PT, and MSP concentrations in rat plasma and urine. Analytical results showed significant differences in ZnPT and PT concentrations between the two shampoo formulations tested in this study. Compared to those in the shampoo formulation without EDTA, ZnPT concentration decreased by approximately 59%, whereas PT concentration increased in the shampoo formulation with EDTA. These results indicated that ZnPT was partially dissociated to PT ion by chelating zinc ion of EDTA.