Ruby Cup · Menstrual Cups
Menstrual Cup
Lower concern; silicone cups lack typical PFAS sources, but brand does not disclose testing.
Ruby Cup menstrual cups are made from medical-grade silicone, a material not typically associated with PFAS use. The product itself has no nonstick, waterproof, or stain-resistant coatings that would warrant PFAS.
Shop Ruby Cup on Amazon →Material
Medical-grade silicone
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
Ruby Cup is manufactured from medical-grade silicone, a synthetic rubber polymer that does not naturally contain the PFAS "forever chemicals" (PFAS) found in some coatings and water-repellent treatments. Medical-grade silicone is thermally stable and chemically inert in contact with vaginal tissues over typical use temperatures (body temperature and cool storage). Unlike some menstrual products, silicone cups do not rely on dyes, fragrance coatings, or adhesive binders that commonly introduce regulated additives.
The brand's record and disclosure
Ruby Cup provides no published transparency report on PFAS testing, heavy metal screening, or third-party certification of silicone purity. The brand does not list FDA clearance, ISO 13485 (medical device standard), or independent lab reports on its website. This silence on material testing is typical of the menstrual cup industry but represents a missed opportunity for consumer confidence. No recalls or safety controversies have been publicly documented for this brand.
How it compares in its category
Menstrual cups as a category carry lower chemical contamination risk than tampons, pads, or disposable applicators because they involve no bleaching, fragrance, adhesives, or wood pulp. Most medical-grade silicone cups (Diva Cup, Lena, Saalt, etc.) have similar material profiles. Ruby Cup differs mainly in brand reputation and user support rather than material safety. Latex cups pose higher allergy risk; cheaper silicone alternatives lack assurance of medical-grade formulation, making purity uncertain.
If you buy it
Boil the cup in water for 5-10 minutes before first use and monthly thereafter to sterilize. Store in a breathable cloth pouch (not sealed plastic) to prevent mold. Replace every 5-10 years or if silicone becomes sticky, discolored, or develops tears. Avoid prolonged exposure to direct sunlight or high heat (above 60°C / 140°F) during storage. Do not use silicone-degrading oils or solvents; wash only with mild soap and water.
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.”
Silicone degradation and leaching
Medical-grade silicone is formulated to resist breakdown under body temperature and vaginal pH. No established research documents leaching of silicone oligomers from menstrual cups at clinically relevant levels, though manufacturer purity testing is not publicly disclosed for Ruby Cup.
Allergenicity and sensitization
Silicone itself is hypoallergenic for most users, but trace dyes, release agents, or vulcanization by-products could theoretically trigger localized sensitivity. Ruby Cup does not disclose additive composition, so individual reactions cannot be ruled out without patch testing reports.
Bacterial colonization risk
If the cup is not boiled or air-dried properly between uses, vaginal bacteria and fungi can proliferate in biofilm on the silicone surface. This is a maintenance issue rather than a manufacturing defect but is user-dependent and not specific to Ruby Cup.
Mold and mildew growth in storage
If stored wet in a sealed plastic case, mold can grow on the silicone and introduce fungal contaminants. Ruby Cup is sold with a storage pouch; proper drying before storage is essential to prevent this.
Heavy metals in silicone pigments (if colored)
Ruby Cup is typically clear or translucent silicone; colored menstrual cups may use iron oxides or other colorants. No lab data on Ruby Cup color composition is publicly available, but clear formulations avoid this exposure pathway.
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 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.