Kosas Review, Is Kosas Non-Toxic?
Kosas averages 75 out of 100 on PFAS Authority's PFAS and toxin screen across the 7 Kosas products graded as of October 2026, and all 7 reach its 70 point pass mark.
Kosas grades Excellent on our four-band scale. On disclosure, the brand says nothing publicly about PFAS. See what every brand has published about PFAS for how that compares.
PFAS Authority is a scoring system, not a laboratory. We do not test products ourselves. Grades are model-based, built from published ingredients, materials, certifications, brand disclosures and third-party lab results where they exist. See the rubric.
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Top-graded picks in the categories readers replace first, every one scored on the same rubric.
- polypropylene filter housing, carbon/sediment cartridge
- We found no PFAS statement from the brand
- Bacterial growth in spent cartridges
3 hazards checked on this product, all on its full breakdown.
Aquasure
Premier Series 75 GPD Under Sink Reverse Osmosis Water Filtration System
- RO membrane, carbon filters, stainless steel housing
- We found no PFAS statement from the brand
- Bacterial and microbial growth in housing and filters
4 hazards checked on this product, all on its full breakdown.
Avocado
Vegan Mattress
- organic cotton, natural latex, coconut coir, recycled steel coils
- The brand calls it PFAS-free, which we have not verified
- Heavy metals
2 hazards checked on this product, all on its full breakdown.
Does Kosas have PFAS, by category
Which Kosas products are PFAS-free? Good or better, best-graded first
- water-based serum and mineral deodorant base
- We found no PFAS statement from the brand
- Fragrance allergens / sensitizers in serum base. No specific fragrance allergen disclosures are available for…
3 hazards checked on this product, all on its full breakdown.
- water-based serum with AHA active ingredients
- We found no PFAS statement from the brand
- 1,4-dioxane contamination. Water-based emulsified cosmetics can harbor trace 1,4-dioxane as a byproduct of…
3 hazards checked on this product, all on its full breakdown.
- Liquid serum with AHA active ingredients, typical cosmetic base
- We found no PFAS statement from the brand
- 1,4-dioxane (preservative byproduct). Liquid cosmetics may contain trace 1,4-dioxane as a byproduct of…
3 hazards checked on this product, all on its full breakdown.
- aqueous cream serum and powder deodorant base
- We found no PFAS statement from the brand
- AHA irritation and skin barrier disruption. This product markets an AHA serum component (likely glycolic or…
- Deodorant base (presumed mineral/plant oil)
- We found no PFAS statement from the brand
- Fragrance allergens and essential oils. Kosas Chemistry lists essential oils and fragrance components (beachy…
2 hazards checked on this product, all on its full breakdown.
- aqueous serum base, AHA active, mineral/plant-derived ingredients
- We found no PFAS statement from the brand
- Formaldehyde / VOCs. Aqueous cosmetics require antimicrobial preservation. Kosas does not publicly detail its…
2 hazards checked on this product, all on its full breakdown.
- Standard cosmetic formulation (deodorant base)
- We found no PFAS statement from the brand
- Fragrance allergens and skin sensitization. Deodorants typically contain fragrance blends (parfum) that may…
3 hazards checked on this product, all on its full breakdown.
What to buy instead Good or better, in the categories Kosas sells
- mineral-based powder blend (arrowroot, magnesium hydroxide, mica)
- We found no PFAS statement from the brand
- Skin irritation from magnesium hydroxide alkalinity
- cosmetic formulations, primary ingredients listed
- A third party reports verifying it as PFAS-free
- Fragrance allergens (natural essential oils)
2 hazards checked on this product, all on its full breakdown.
- natural mineral powders, plant-based actives, beeswax
- We found no PFAS statement from the brand
- Beeswax purity and contamination
2 hazards checked on this product, all on its full breakdown.
Kosas and PFAS, common questions
- Does Kosas have PFAS?
- Kosas averages 75 out of 100 on PFAS Authority's PFAS and toxin screen across the 7 Kosas products graded as of October 2026, and all 7 reach its 70 point pass mark. Grades are model-based estimates built from published materials, ingredients and disclosures, not lab tests.
- Is Kosas non-toxic?
- Chemistry AHA Serum Kosas Deodorant is the highest-graded Kosas product we have scored, at 75/100. It depends on the product line rather than the brand, so check the grade of the exact item you are buying.
- Which Kosas products are lower concern for PFAS?
- The highest-graded Kosas products we have scored are Chemistry AHA Serum Kosas Deodorant, Kosas Chemistry AHA Serum Deodorant, Kosas Chemistry AHA Serum Deodorant Fragrance Free. That is our model-based estimate from materials and public disclosure, not a lab test.
Every grade uses the same public rubric. How grades work →