Kosas · Deodorant
Kosas Chemistry Deodorant - Aluminium and Baking Soda Free + BO-Fighting AHA Serum that Exfoliates Softens and Nourishes the Skin (Fragrance Free)
Lower concern; liquid/powder cosmetic with no PFAS-prone coatings, but brand makes no explicit safety claim.
This deodorant and serum are formulated as aqueous creams and powders without waterproof or stain-resistant treatments typical of PFAS use in cosmetics. No known PFAS-prone ingredients (silicones, fluorinated polymers, or water-repellent coating coatings) are standard to this product type.
Shop Kosas on Amazon →Material
aqueous cream serum and powder deodorant base
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Category baseline
cosmetics is a category where PFAS exposure is more common.
No PFAS disclosure
No public statement about PFAS in this product.
Safe base material
Made from a material with no inherent PFAS use (ceramic, mineral, or natural fiber).
The full breakdown
What it's made of and why it matters
Kosas Chemistry is formulated as an aqueous cream-serum base combined with powder, designed to work without aluminum salts or sodium bicarbonate. The product uses an AHA (alpha-hydroxy acid) exfoliant and humectant oils to manage odor and skin condition rather than relying on anti-perspirant chemistry. This aqueous-powder hybrid avoids the coating degradation and aluminum leaching risks of traditional antiperspirants while minimizing exposure to harsh baking soda irritation. The fragrance-free formulation eliminates synthetic fragrance allergen and volatile organic compound (VOC) exposure.
The brand's record and disclosure
Kosas is owned by Estee Lauder Companies and maintains public ingredient transparency on product pages; the brand does not make explicit PFAS-free claims but provides detailed ingredient lists that do not indicate PFAS-prone coatings or water-repellent treatment. The brand has no publicized safety recalls or regulatory actions on record for this deodorant line. Certifications or third-party testing data for this specific product are not widely documented in public sources.
How it compares in its category
Aluminum-free deodorants are increasingly common, but Kosas' combination of cream base plus AHA chemistry is less typical than baking-soda-free powders or charcoal-based alternatives. Most aluminum-free deodorants still use baking soda; this product eliminates both, reducing irritation risk for sensitive skin but relying on exfoliation rather than odor absorption. Compared to aluminum-containing antiperspirants, this carries lower heavy-metal leaching risk and no Teflon-type coating fume exposure from non-stick coatings (which do not apply to deodorants anyway).
If you buy it
Store in a cool, dry place away from direct heat; the cream-powder consistency can separate or dry out if exposed to high temperatures or humidity for extended periods. Apply to clean, dry skin; the AHA content may cause mild irritation if used on freshly shaved or damaged skin. Replace every 12-18 months or when consistency changes significantly. Discontinue if redness, itching, or sensitization develops; AHA exfoliants are not suitable for all skin types and may interact with other actives.
Beyond PFAS: other things we checked
Established hazard classes for this product type, assessed from public information. These never change the PFAS grade; a Likely flag caps the Verdict at “Buy with care.”
Formaldehyde releasers (preservative concern)
No formaldehyde or formaldehyde-releasing preservatives are listed in publicly available ingredient disclosures for this product. Aqueous cream formulas typically use paraben or other non-releasing systems.
Heavy metals in pigments and powder actives
No synthetic colorants or heavy-metal-prone mineral powders are documented in the ingredient list. The product is fragrance-free and uses natural or synthetic mica/talc-adjacent powders which are not typically contaminated if sourced from regulated cosmetic suppliers.
Talc contamination (if talc is present)
Product ingredient disclosures do not indicate talc use; powder base is unclear but brand does not promote talc as a component. If talc is used, asbestos risk is minimal under FDA cosmetic-grade talc regulations, though long-term inhalation exposure remains a category concern for powder deodorants generally.
AHA irritation and skin barrier disruption
This product markets an AHA serum component (likely glycolic or lactic acid). While beneficial for exfoliation, regular AHA use can cause irritation, photosensitivity, and barrier damage in sensitive individuals. Applying exfoliating acids to the underarm daily is not standard dermatological practice and may cause cumulative irritation.
Fragrance allergens (fragrance-free claim)
Product is labeled fragrance-free, which eliminates synthetic fragrance allergen exposure. However, natural fragrance compounds in oils or extracts (if present) could still trigger contact dermatitis in sensitive individuals; full ingredient review is recommended for known fragrance sensitivities.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 72% confidence. It is not a lab result.
No independent PFAS lab test is on record for this exact product. A lab test could move the score in either direction.
The brand has not made a specific, verifiable PFAS-free statement, so part of this score reflects that missing disclosure rather than a confirmed material.
Formulations and coatings change between production runs. Always check the current label before buying.
Safer alternatives in Deodorant
Tom's of Maine
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⚠Risky category by default
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⚠Risky category by default
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Antiperspirant Deodorant
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✓Verified PFAS-free by a third party
More deodorant 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.