Aisle · Menstrual Cups
Scarlet by RedDrop Menstrual Cup
Lower PFAS concern for a silicone menstrual cup; brand silence on PFAS is typical for category.
Scarlet by Aisle is a medical-grade silicone menstrual cup with no known Teflon-family coating coatings, nonstick treatments, or waterproofing agents that typically introduce PFAS. Silicone itself does not require PFAS for function.
Shop Aisle on Amazon →Material
Medical-grade silicone (primary component)
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
Category baseline
period care 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
Scarlet is constructed from medical-grade silicone, a thermoset polymer chosen for menstrual cups because it resists degradation, doesn't leach estrogenic compounds like BPA-containing plastics, and tolerates repeated sterilization by boiling or autoclaving. Medical-grade silicone is inert at body temperature and vaginal pH, meaning chemical migration into menstrual fluid or vaginal tissue is not a documented concern for this material class. The cup's rigid-yet-flexible design depends on the silicone's stability; degradation would manifest as visible cracking or loss of seal integrity long before chemical leaching becomes a risk.
The brand's record and disclosure
Aisle (the parent company) does not publish independent third-party certifications, material safety data sheets, or explicit PFAS testing results for Scarlet on their consumer-facing materials. This silence on PFAS and heavy metals is typical for menstrual cup brands and reflects both the lower inherent risk of silicone and gaps in industry-wide disclosure standards. No product recalls, contamination reports, or safety controversies specific to Scarlet are documented in public databases. The brand emphasizes sustainability and reusability but does not specify manufacturing origin or provide detailed ingredient traceability.
How it compares in its category
Medical-grade silicone menstrual cups are considered the safest category option, avoiding the BPA and phthalate risks of some plastic or thermoplastic elastomer (TPE) alternatives and the latex allergy risk of rubber cups. Scarlet's positioning within premium reusable cups is comparable to widely used brands like Lunette, DivaCup, and Saalt, all of which use identical silicone chemistry with similar transparency gaps. The main differentiator is stem design and firmness; safety profile is functionally equivalent across this material class.
If you buy it
Boil or steam-sterilize Scarlet between cycles to prevent bacterial biofilm growth, which is the primary hygiene risk for any menstrual cup regardless of material. Inspect the silicone monthly for visible cracks, discoloration, or odor changes; replace if the cup becomes sticky, hard, or visibly degraded (typically after 5-10 years of use). Do not expose to prolonged contact with petroleum-based lubricants or essential oils, which can soften silicone. Store dry in a breathable pouch, not sealed or in plastic bags, to prevent mold.
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.”
Bacterial growth / biofilm formation
Like all menstrual cups, Scarlet can harbor pathogenic bacteria if not boiled between cycles or if left wet in non-breathable storage. This is a use and maintenance issue, not a material defect; proper care eliminates the risk.
Silicone degradation and leaching
No credible reports of Scarlet or medical-grade silicone menstrual cups degrading or leaching chemicals into vaginal fluid under normal use. Silicone is chemically inert at body temperature and pH.
Allergic sensitization or irritation
A small fraction of users report vulvovaginal irritation attributed to menstrual cup use, though causality is debated; likely related to insertion trauma, individual sensitivity, or pre-existing conditions rather than silicone toxicity. No Scarlet-specific adverse event pattern is documented.
Heavy metals in pigments or additives
Aisle does not disclose third-party heavy metal testing for Scarlet. Medical-grade silicone production standards typically exclude lead and cadmium, but without published results, this cannot be confirmed for this specific product.
Formaldehyde or other sterilant residues
Scarlet is not sterilized by ethylene oxide (ETO) at the factory per available product information, reducing formaldehyde residue risk common in some medical devices. Final sterilization method is not explicitly stated.
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 Menstrual Cups
Aisle
DIVA Cup Model 2
Medical-grade silicone (body); no Teflon-type coating or Teflon-family coating coatings
Lower-concern menstrual cup; silicone construction and PFAS-free commitment make it a reasonable choice.
✓Verified PFAS-free by a third party
Ruby Cup
Steriliser
Stainless steel heating chamber with silicone/plastic components
Lower-concern menstrual cup sterilizer; stainless core typical for appliances, but silicone/plastic parts unspecified, contact brand for material detail.
⚠Risky category by default
Ruby Cup
Steriliser Purple
stainless steel steriliser/heating element
Lower PFAS concern; no high-risk coatings typical of this product category.
⚠Risky category by default
More menstrual cups 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.