Sensodyne · Dental Floss
Sensodyne Expanding Dental Floss
Lower concern; traditional nylon floss with no known PFAS risk, but coating composition not disclosed.
Sensodyne Expanding Floss is a standard nylon-based dental floss with wax coating. The brand makes no PFAS claims and does not disclose the exact composition of its coating.
Shop Sensodyne on Amazon →Material
Nylon filament (primary); polyester core; wax/resin coating (unspecified type)
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
Sensodyne Expanding Dental Floss is primarily nylon filament wound around a polyester core, coated with an unspecified wax or resin blend. Nylon and polyester are inert, non-toxic polymers with decades of oral-use safety history. The expanding mechanism (floss widens when wet) is a mechanical design feature, not a chemical additive, so it poses no leaching risk. The wax/resin coating composition is proprietary and not disclosed, which limits our ability to assess for specific additives like colorants or antimicrobial agents.
The brand's record and disclosure
Sensodyne (owned by GSK) is a major oral-care brand with no published recalls or safety controversies for dental floss. The company does not publicly disclose coating chemistry or certifications specific to this floss product. No independent testing data or regulatory red flags are on record. Sensodyne has not made formal PFAS-free claims for this product, though traditional nylon floss carries no known PFAS risk.
How it compares in its category
Expanding nylon floss is a mainstream subcategory; Sensodyne's version is typical in material and design. Alternatives (Teflon-type coating-based flosses like Glide, waxed silk, charcoal-infused nylon) differ in coating and substrate but carry similar or equivalent safety profiles in normal use. No dental floss category has established toxic-hazard advantages; choice is largely based on effectiveness and user preference. Sensodyne's lack of transparency on wax/resin type is neither unusual nor a red flag in this product class.
If you buy it
Dental floss is not ingested in meaningful quantities and poses minimal systemic risk from coating residues under normal use. Replace the spool when filaments fray or snap, as this indicates nylon degradation and reduced cleaning efficacy. Store in a cool, dry place to prevent mold growth on the wax coating. No heating, boiling, or microwaving is relevant to this product; normal ambient conditions are sufficient.
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.”
Wax/resin coating composition (unspecified)
The manufacturer does not disclose the exact chemical makeup of the floss coating. Standard dental-floss waxes are food-grade paraffin or beeswax blends, both safe for oral use, but without published ingredient data, specific additives (colorants, preservatives) cannot be verified. Risk of coating ingestion is minimal given floss usage patterns.
Nylon degradation and microfiber shedding
Worn or frayed nylon filaments may shed microscopic fibers during use, though the amount swallowed is negligible and nylon is not absorbed in the GI tract. No established health risk from nylon microfibers in dental floss has been documented. Replace when visibly worn to minimize this theoretical exposure.
Allergic reaction to coating or nylon
Rare cases of contact sensitivity to dental-floss waxes or nylon itself have been reported, typically manifesting as gum irritation rather than systemic reaction. Individuals with known polyamide (nylon) allergies should avoid or patch-test. No adverse-event reports specific to Sensodyne Expanding Floss are on record.
Bacterial growth if stored damp
Floss stored in humid bathrooms without a protective case may support mold or bacterial biofilm on the wax coating, though ingestion of low-level microbial contamination poses minimal risk. Store in a closed dispenser or airtight container to prevent moisture accumulation.
Teflon-type coating or Teflon-family coating (unlikely but unconfirmed)
Sensodyne Expanding Floss uses nylon and polyester, not Teflon-type coating (Teflon); however, the unspecified wax/resin could theoretically include trace Teflon-family coating additives. No evidence suggests this is the case, and Teflon-type coating in floss is not an established safety concern at oral doses. The PFAS verdict of 75/100 reflects this low likelihood.
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 Dental Floss
Cocofloss
Refill Trio
Coconut fiber, based floss with plant-based coating
Lower-concern dental product; natural materials and transparent PFAS stance, but no independent verification.
⚠Risky category by default
Dental Lace
Refillable Silk Dental Floss
Silk floss with compostable refillable packaging
Lower concern; silk floss with credible PFAS-free positioning and third-party certification.
✓Verified PFAS-free by a third party
Dental Lace
Plant Based/Vegan Floss Refillable Glass Container PFAS-Free (2 Spools/4-
Plant-based vegan floss (likely plant cellulose or silk fibers)
Lower-concern product with explicit PFAS-free claim; no third-party verification limits certainty.
⚠Risky category by default
More dental floss 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.