Collagen Facial Serum

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

• common irritantPROPYLENE GLYCOL, IMIDAZOLIDINYL UREA

  • 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).
  • IMIDAZOLIDINYL UREA: A preservative the FDA lists as a formaldehyde releaser, so formaldehyde-reactive skin can notice it. How much reaches the skin depends on the whole formula, not on this name alone. EU Regulation (EC) 1223/2009, Annex V entry 27, permits imidazolidinyl urea as a preservative up to 0,6%. The FDA names it among the "formaldehyde and formaldehyde releasing ingredients" on its Allergens in Cosmetics page (content current 25 February 2022). Annex V preamble point 2, as amended by Commission Regulation (EU) 2022/1181, requires the warning "releases formaldehyde" on any product whose total released formaldehyde exceeds 0,001% (10 ppm). That Regulation states the sensitisation ground itself, so the chain is drawn by the regulator and not by us: recital (2) names the class, "Certain of those preservatives are gradually releasing formaldehyde in order to fulfil a preserving function in the final cosmetic product (so called formaldehyde releasers)", and recital (3) gives the purpose of the warning, "In order to inform consumers sensitised to formaldehyde about the presence of formaldehyde that may trigger an allergic reaction". Recital (1) records that formaldehyde is classified a skin sensitizer (Category 1) in Part 3 of Annex VI to Regulation (EC) 1272/2008.

• fragrance materialBENZYL ALCOHOL

  • 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.

• undeclared fragrance blendFRAGRANCE/PARFUM

  • FRAGRANCE/PARFUM: 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 acidLACTIC ACID

  • LACTIC 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."

• retinoidRETINYL PALMITATE

  • RETINYL PALMITATE: A gentler vitamin A ester that the skin converts to retinol. SCCS Opinion on Vitamin A (Retinol, Retinyl Acetate, Retinyl Palmitate), SCCS/1576/16, which assesses retinyl palmitate by name; EU Regulation (EC) 1223/2009 Annex III entry 376 covers it in the same group as retinol.

• 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, UREA, SODIUM HYALURONATE, PANTHENOL

  • 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".
  • UREA: A humectant the skin already makes; at higher levels it also softens thickened skin. StatPearls, "Moisturizers", NCBI Bookshelf NBK545171, updated 12 February 2024: "Urea is a component of NMF. The addition of urea to moisturizers helps with the absorption of water into the stratum corneum." The FDA label for prescription-strength urea calls it keratolytic and states that its mechanism of action is not yet known.
  • SODIUM HYALURONATE: A humectant that holds a large amount of water at the skin surface. Chylińska N, Maciejczyk M, "Hyaluronic Acid and Skin: Its Role in Aging and Wound-Healing Processes", Gels 2025;11(4):281, DOI 10.3390/gels11040281, PMID 40277717, open access: hyaluronic acid's "high osmotic activity and anionic structure enable it to bind large amounts of water", and "sodium and potassium hyaluronate are widely used in moisturizing products". The same review notes that high-molecular-weight hyaluronic acid does not penetrate the deeper layers.
  • PANTHENOL: A provitamin B5 humectant used in products aimed at irritated and healing skin. On the humectant half: Ferreira VTP, Silva GC, Martin AA, Maia Campos PMBG, "Topical dexpanthenol effects on physiological parameters of the stratum corneum by Confocal Raman Microspectroscopy", Skin Res Technol 2023;29(9):e13317, DOI 10.1111/srt.13317, PMID 37753694, PMCID PMC10504581, open access, Introduction: "As a humectant, it has been shown to retain water more efficiently than other humectants during the last stages of dehydration..." On the soothing half, which that paper does NOT support: Cho YS, Kim HO, Woo SM, Lee DH, "Use of Dexpanthenol for Atopic Dermatitis—Benefits and Recommendations Based on Current Evidence", J Clin Med 2022;11(14):3943, DOI 10.3390/jcm11143943, PMID 35887707, open access, section 3.5: "To facilitate wound healing, dexpanthenol reduces inflammation, and promotes cell proliferation and epithelial remodeling."

• soothingALLANTOIN, PANTHENOL

  • ALLANTOIN: A skin protectant used at low levels in products aimed at irritated skin. FDA OTC skin protectant monograph, 21 CFR 347.10(a), lists allantoin as a skin-protectant active at 0,5 to 2%. Its labelled indications are 21 CFR 347.50(b)(1), "temporarily protects minor: cuts, scrapes, burns", and (b)(2), which covers chafed, chapped or cracked skin. The monograph does not give it the "minor skin irritation and itching" wording; that one belongs to colloidal oatmeal, sodium bicarbonate and one combination, and to topical starch without the itching half.
  • PANTHENOL: A provitamin B5 humectant used in products aimed at irritated and healing skin. On the humectant half: Ferreira VTP, Silva GC, Martin AA, Maia Campos PMBG, "Topical dexpanthenol effects on physiological parameters of the stratum corneum by Confocal Raman Microspectroscopy", Skin Res Technol 2023;29(9):e13317, DOI 10.1111/srt.13317, PMID 37753694, PMCID PMC10504581, open access, Introduction: "As a humectant, it has been shown to retain water more efficiently than other humectants during the last stages of dehydration..." On the soothing half, which that paper does NOT support: Cho YS, Kim HO, Woo SM, Lee DH, "Use of Dexpanthenol for Atopic Dermatitis—Benefits and Recommendations Based on Current Evidence", J Clin Med 2022;11(14):3943, DOI 10.3390/jcm11143943, PMID 35887707, open access, section 3.5: "To facilitate wound healing, dexpanthenol reduces inflammation, and promotes cell proliferation and epithelial remodeling."