Function of Beauty Custom Shampoo
Lower PFAS concern. Rinse-off liquid shampoo with no warning signs detected.
This water-based liquid shampoo has no water-repellent, stain-resistant, or Teflon-family coating treatments. The brand makes no PFAS claims. Rinse-off shampoos generally carry lower PFAS contamination risk than leave-on or treated-surface products.
We flunk more products than we pass. This one earned its grade. How we grade
Material
water-based liquid shampoo, proprietary formulation
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
What’s concerning
No PFAS disclosure
The company has not publicly discussed PFAS in this product.
Category baseline
cosmetics is a category where PFAS exposure is more common.
Fragrance allergens and undisclosed fragrance chemicals
Shampoos commonly contain fragrance mixes; Function of Beauty does not publicly itemize fragrance components, meaning potential allergens like limonene, linalool, or oakmoss are not pre-screened. Customization does not guarantee fragrance transparency.
1,4-dioxane contamination in surfactants
Shampoos using ethoxylated surfactants (common in rinse-off formulas) may contain trace 1,4-dioxane as a manufacturing byproduct. Function of Beauty does not disclose surfactant type or whether vacuum distillation (removal step) was used.
Preservative-induced contact dermatitis
Commonly used preservatives in shampoos (methylchloroisothiazolinone, phenoxyethanol) trigger contact dermatitis in sensitive individuals. Customization marketing does not guarantee hypoallergenic or preservative-free formulation without explicit labeling.
What’s reassuring
Safe base material
Made from ceramic, mineral, or natural fiber with no PFAS risk.
Formaldehyde / VOCs
No public evidence that Function of Beauty uses formaldehyde releasers (DMDM hydantoin, imidazolidinyl urea), but proprietary formula opacity means this cannot be ruled out without ingredient disclosure.
Source: ATSDR ↗Heavy metals
Colored shampoos can contain iron oxides or synthetic pigments with trace metals; no recalls or warnings on record for Function of Beauty products, and liquid shampoos present lower risk than solid cosmetics.
Source: FDA ↗The full breakdown
What it's made of and why it matters
Function of Beauty Custom Shampoo is a water-based liquid formulation marketed with personalized ingredient selection. The brand does not publicly disclose full ingredient transparency beyond marketing claims, making independent hazard assessment difficult. As a rinse-off product (unlike leave-on cosmetics), exposure duration and absorption are inherently lower. Proprietary blends mean you cannot verify presence or absence of specific chemical additives without requesting a full Safety Data Sheet.
The brand's record and disclosure
Function of Beauty has not published comprehensive ingredient lists or third-party certifications (e.g., EWG Verified, Leaping Bunny) on their shampoo line. The brand markets customization and natural-sounding language but remains silent on PFAS use, formaldehyde releasers, or preservative choice. No major product recalls or published safety incidents have been documented for this shampoo. Limited disclosure makes it harder to assess compliance with cosmetic safety standards than brands with full transparency.
How it compares in its category
Typical shampoos contain preservatives (methylisothiazolinone, phenoxyethanol) and fragrance compounds; Function of Beauty's proprietary formula obscures whether these are used. Customization marketing is a consumer differentiator but does not inherently improve safety profile compared to mainstream shampoos. Brands like Vanicream and Cetaphil publish full ingredient disclosure and third-party vetting; Function of Beauty does not. Price point and personalization appeal are higher than mass-market shampoos but transparency is not.
If you buy it
Rinse-off shampoos present minimal dermal absorption risk compared to leave-on products. If you have sensitive scalp, fragrance sensitivity, or contact dermatitis history, request the full ingredient list before purchase to verify preservative and fragrance chemicals. Store in a cool, dry place away from direct sunlight to preserve formula stability. Discontinue use immediately if scalp irritation, itching, or allergic reaction occurs and patch-test on a small scalp area first if concerned.
What we don’t know
- Basis
- Model estimate, 72% confidence, not a lab result
- Lab test
- None on record for this exact product
- Brand statement
- Function of Beauty has made none
Formulations change between production runs, so check the current label. How we grade.
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Puracy
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Puracy
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Lower concern for a liquid shampoo with minimal PFAS risk in this category.
⚠Risky category by default
More shampoo grades
How we score: every product runs through the same public 0–100 rubric based on materials, coatings, brand disclosure, lab findings, and recalls. See the full methodology → Spotted a mistake? Report an error.