Crest · Dental Floss
Crest Shred Guard Floss, Mint
Lower PFAS concern for typical nylon dental floss; no known treatment triggers.
Crest Shred Guard Floss is standard nylon dental floss with no reported PFAS coatings or water-resistant treatments typical of high-risk products. The brand does not disclose PFAS information, which is common for this category. No public lab data or recalls flag this product.
Shop Crest on Amazon →Material
Nylon filament (standard dental floss)
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
Crest Shred Guard Floss is a nylon monofilament or twisted nylon construction, a standard material for dental floss that has been used safely for decades. The nylon core is coated with wax (typically paraffin or beeswax blend) and mint flavoring to aid slip and palatability. Nylon does not leach monomers or plasticizers during normal oral use because it is a condensation polymer with minimal residual chemicals, and the brief contact time (seconds per day) in the mouth limits any theoretical exposure. The mint flavoring is typically a food-grade essential oil or synthetic flavoring agent at trace levels, well below oral irritation thresholds for the target age group.
The brand's record and disclosure
Crest (Procter and Gamble) does not publicly disclose material sourcing or chemical composition details for dental floss beyond ingredient names on packaging. The brand has no known recalls or safety controversies specific to Shred Guard Floss. Crest products generally comply with FDA oral care device regulations and ingredient standards (Code of Federal Regulations Title 21), though the company rarely publishes third-party safety testing or certification beyond regulatory minimum.
How it compares in its category
Crest Shred Guard Floss is a conventional waxed nylon floss, identical in material class to generic and store-brand dental floss. Its main differentiation is the wax formulation designed to reduce shredding and improve glide, not material safety. Compared to silk floss (biodegradable but similar chemical safety profile) or water flossers (different delivery mechanism), nylon floss carries no known added hazards. Price and performance are the primary consumer choice drivers in this category, not safety differentiation.
If you buy it
Use as directed: one length (18-24 inches) per flossing session, discarded after single use. No storage concerns; keep in a cool, dry place to prevent wax softening. Replace the container or spool if the dispenser becomes contaminated. Floss is not swallowed in normal use, so ingestion hazard is negligible; supervise young children to ensure they do not consume floss. Discontinue use if gum irritation or allergic reaction (rare, typically to mint flavoring) occurs.
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.”
Mint flavoring allergens
Mint flavoring (menthol or peppermint oil) can trigger contact irritation or rare allergic reaction in individuals with mint sensitivity or inflamed gums. Reactions are mild and localized to oral tissue; no systemic risk at typical floss flavoring concentrations.
Wax coating degradation or shedding
The paraffin or beeswax coating is designed to remain on the floss during use and is swallowed in negligible amounts. No established toxicity for food-grade wax at these trace exposures; not a safety concern in standard use.
Nylon microfiber ingestion
Nylon floss does not fragment into microfibers during normal flossing. Any theoretical fibers swallowed are non-toxic and eliminated without absorption; no known health impact in the dental floss literature.
Colorant or dye allergens
Mint-flavored floss typically contains food-approved colorants (e.g., FD&C Blue No. 1) at trace levels. No azo dyes or heavy metal pigments are used in dental floss; regulatory approval for oral products is stricter than for textiles or cosmetics.
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.