Scalp Sync Pyrithione Zinc Antidandruff Shampoo

These describe what an ingredient is, not whether it is a problem. The stance marks above are the ratings; these are not.

• common irritantsodium lauryl sulfate, coco-betaine, propylene glycol, methylisothiazolinone

  • sodium lauryl sulfate: A strong cleansing agent used as the reference irritant in skin-irritation testing. OECD Test Guideline 439 (in vitro skin irritation, reconstructed human epidermis), paragraph 24: "The suggested PC is 5% aqueous SDS", sodium dodecyl sulphate, the same substance as sodium lauryl sulfate, CAS 151-21-3.
  • coco-betaine: A mild cleansing agent, but a recurring patch-test finding, usually traced to leftovers from how it is made. American Contact Dermatitis Society, Allergen of the Year 2004 (Fowler JF Jr, Dermatitis 2004;15(1):3-4).
  • propylene glycol: A solvent that shows up in patch-test clinics, more often as irritation than as allergy. American Contact Dermatitis Society, Allergen of the Year 2018 (Jacob SE, Scheman A, McGowan MA, Dermatitis 2018;29(1):3-5).
  • methylisothiazolinone: A preservative that patch-test clinics see reactions to often enough that the EU banned it from leave-on products. American Contact Dermatitis Society, Allergen of the Year 2013 (Castanedo-Tardana MP, Zug KA, Dermatitis 2013;24(1):2-6); SCCS Opinion on Methylisothiazolinone (P94), Submission II, SENSITISATION ONLY (SCCS/1521/13, revision of 27 March 2014); banned in leave-on cosmetics by Commission Regulation (EU) 2016/1198, which recites the need to address "the increased incidence of allergies induced by methylisothiazolinone".

• fragrance materialmenthol, limonene, hexyl cinnamal, coumarin, benzyl alcohol, linalool, amyl cinnamal

  • menthol: The cooling component of mint oils, named by the EU as a fragrance substance to be declared on the label. EU Regulation (EC) 1223/2009, Annex III entry 338, inserted by Commission Regulation (EU) 2023/1545: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products. It is declarable in its OWN right, not by way of any component it carries. The name to look for on a label is "Menthol". The duty applies now. Transition footnote (40) lets stock that does not comply, lawfully placed on the Union market before the 31 July 2026 cut-off, be made available until 31 July 2028.
  • limonene: A citrus-smelling fragrance component named separately on the label; the one name covers three related isomers. EU Regulation (EC) 1223/2009, Annex III entry 88: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk. That entry carries transition footnote (37): stock that does not comply, lawfully placed on the Union market before the 31 July 2026 cut-off, may still be made available until 31 July 2028. It is marked on the racemic dl-limonene/Dipentene line and the (S)-(l-limonene) line, but NOT the (R)-p-mentha-1,8-diene (d-limonene) line, CAS 5989-27-5, whose duty was already running as entry 88 before Commission Regulation (EU) 2023/1545 and so needed no transition. All three isomers are declared under the single glossary name "Limonene", so that name on a label does not identify which of them is present.
  • hexyl cinnamal: A jasmine-like fragrance component named separately on the label. EU Regulation (EC) 1223/2009, Annex III entry 87: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk.
  • coumarin: A sweet hay-scented fragrance component named separately on the label. EU Regulation (EC) 1223/2009, Annex III entry 77: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk.
  • benzyl alcohol: Used both as a fragrance component and as a preservative; the EU names it either way. EU Regulation (EC) 1223/2009, Annex III entry 45: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk. That entry carries transition footnote (38), which is footnote (37) plus a condition: stock that does not comply may still be made available until 31 July 2028 only "provided that they comply with the restrictions applicable on 15 August 2023", and only if it was lawfully placed on the Union market before the 31 July 2026 cut-off. Entry 45 covers its non-preservative use; it is separately an allowed preservative at Annex V entry 34.
  • linalool: A floral fragrance component named separately on the label. EU Regulation (EC) 1223/2009, Annex III entry 84: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk.
  • amyl cinnamal: A jasmine-like fragrance component named separately on the label. EU Regulation (EC) 1223/2009, Annex III entry 67: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk.

• undeclared fragrance blendfragrance

  • fragrance: A blend the label does not itemize, so what is in it cannot be read from the ingredient list. EU Regulation (EC) 1223/2009 permits the collective term "parfum"; the SCCS Opinion on Fragrance Allergens (SCCS/1459/11) reviews the contact-allergy evidence for the substances it can contain.

• exfoliating acidglycolic acid, salicylic acid

  • glycolic acid: An alpha hydroxy acid that loosens surface skin cells; it also makes skin more sun-sensitive while you use it. FDA, "Guidance for Industry: Labeling for Topically Applied Cosmetic Products Containing Alpha Hydroxy Acids as Ingredients" (announced at 70 FR 1721, 10 January 2005; FDA web pages title it "Labeling for Cosmetics Containing Alpha Hydroxy Acids"), which names this acid and recommends the statement "Sunburn Alert: This product contains an alpha hydroxy acid (AHA) that may increase your skin's sensitivity to the sun and particularly the possibility of sunburn."
  • salicylic acid: A beta hydroxy acid that clears the inside of pores; the EU restricts its level and keeps it off children under three. SCCS Opinion on Salicylic Acid, Submission I (SCCS/1601/18, corrigendum of 20 to 21 June 2019); EU Regulation (EC) 1223/2009 Annex III entry 98, as amended by Commission Regulation (EU) 2021/850, which for purposes other than preservation caps it at 3,0% in rinse-off hair products, 2,0% in other products, and 0,5% in body lotion, eye shadow, mascara, eyeliner, lipstick and roll-on deodorant, and states "Not to be used in preparations for children under 3 years of age." Its separate PRESERVATIVE use sits at Annex V entry 3, capped at 0,5% (acid), where the salts carry the carve-out "except for shampoos".

• rich occlusivedimethicone

  • dimethicone: A silicone that forms a film on the surface of the skin without an oily feel. FDA OTC skin protectant monograph, 21 CFR 347.10(g), lists dimethicone as a skin protectant at 1 to 30%.

• humectantglycerin

  • glycerin: A humectant, and one of the two ingredients a comparison of moisturiser components found made a significant difference to skin hydration. FDA OTC skin protectant monograph, 21 CFR 347.10(h), lists glycerin as a skin protectant at 20 to 45%. On the humectant half: Jeong CB, Han JY, Cho JC, Suh KD, Nam GW, "Analysis of electrical property changes of skin by oil-in-water emulsion components", Int J Cosmet Sci 2013;35(4):402-410, DOI 10.1111/ics.12059, PMID 23621673, found that "glycerine and urea showed significant skin hydration effects compared with other humectants".