Radius · Dental Floss
Radius Natural Biodegradable Silk Floss
Lower-concern choice; natural silk fiber has no inherent PFAS trigger, but brand offers no explicit disclosure.
Radius markets this floss as biodegradable silk with plant-based wax, materials historically not requiring PFAS for function. The brand makes no PFAS claims and provides no third-party testing data. No red flags in the product category itself, but lack of transparency means modest confidence.
Shop Radius on Amazon →Material
Silk fiber, plant-based wax coating
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
Radius Natural Biodegradable Silk Floss is composed of mulberry silk fiber wound with a plant-based wax coating (typically candelilla or similar vegetable wax). Silk is a protein fiber with no inherent toxicology concerns in oral use, and plant waxes avoid synthetic polymer coatings that sometimes harbor PFAS or release microplastics. The biodegradable claim is material-credible: both silk and plant waxes break down in standard composting within months, unlike nylon or teflon-coated alternatives.
The brand's record and disclosure
Radius is a smaller oral-care brand focused on natural and sustainable products, with established presence in health-conscious retail channels. The brand does not provide explicit third-party testing results or PFAS certifications on this product, and marketing materials lack detailed ingredient sourcing or chemical safety statements. No recalls, adverse event reports, or regulatory actions are on record for this floss. The lack of transparency is notable but not unusual for the dental-floss category, where ingredient disclosure is rarely comprehensive.
How it compares in its category
Most conventional flosses (nylon-based, especially with Teflon-type coating) carry higher PFAS risk and persist in the environment for decades. Silk-based flosses are a minority choice but rank among the lowest-chemical alternatives. Compared to other natural options (unwaxed silk, vegan plant-fiber blends), Radius includes wax for glide, which is a practical trade-off; the plant-wax choice avoids synthetic coatings found in mainstream brands. Price is typically 2-3x higher than standard nylon floss, reflecting material sourcing and smaller production volume.
If you buy it
Floss is a low-dose, short-contact-time product (seconds per day in the mouth), so chemical migration risk is minimal even if coatings were problematic. Use as directed; silk is durable and will not shed microfibers under normal interdental friction. Store in a dry place to prevent mold growth on the natural fibers, though floss spent quickly makes this unlikely. If the wax coating feels sticky or rancid after long storage, discard and replace; plant waxes can degrade over time in humid conditions.
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.”
Plant wax coating degradation or allergen content
Plant-based waxes (candelilla, carnauba, etc.) are well-tolerated and used in food products; no allergen or toxicological concerns documented for this product or material class. Oral contact is brief and minimal ingestion occurs.
Silk protein allergens or irritation
Silk fiber poses no known oral toxicity. Rare individuals with severe silk allergy might experience contact sensitivity, but this is not documented as a category-level concern for dental floss products.
Microbial growth on natural fiber storage
Silk and plant waxes can theoretically support mold or bacterial growth if stored in high humidity for extended periods; however, the small volume and rapid consumption of floss makes this a low practical risk. Standard dry storage mitigates this fully.
Heavy metals in silk or wax coatings
No third-party testing or recalls indicate heavy metal contamination (lead, cadmium, arsenic) in silk floss products. Mulberry silk production does not inherently expose fibers to metallurgic hazards, and plant waxes do not concentrate metals. No data contradicts safety in this product specifically.
Formaldehyde or synthetic resin finishing
Natural silk floss with plant-wax coating avoids the synthetic polymer finishing agents and formaldehyde-releasing resins found in conventional nylon flosses. No evidence of formaldehyde-based processing in this product line.
What we don’t know
This grade is a model-based estimate from public materials, coatings, and brand disclosure at 78% 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.