Sub-Zero · Refrigerator Filters
Sub-Zero Refrigerator Water Filter Replacement 4204490
Lower-concern appliance filter; activated carbon & resin are standard materials without inherent PFAS risk, but Sub-Zero offers no public PFAS transparency.
Sub-Zero water filters use conventional activated-carbon and ion-exchange-resin technology, materials not typically associated with PFAS contamination. However, the brand makes no public PFAS claims or third-party verification, typical silence in this category.
Shop Sub-Zero on Amazon →Material
Activated carbon, ion-exchange resin cartridge filter
Brand disclosure
Brand is silent on PFAS
Lab data
No public lab test
Why this grade
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
This filter uses activated carbon (a porous form of carbon that adsorbs contaminants) combined with ion-exchange resin, which removes dissolved minerals and some chemical residues from water. Both materials are chemically stable and do not leach into water under normal refrigerator operating conditions (ambient temperature, low pressure). The cartridge housing is typically food-grade plastic or composite material designed to contain these media without degradation during the filter's rated lifespan.
The brand's record and disclosure
Sub-Zero does not publish detailed material safety data or independent third-party certifications for this specific filter model on their public website. The brand has no recorded product recalls or safety controversies related to water filters. Sub-Zero maintains silence on PFAS transparency rather than making explicit claims; the activated carbon and resin materials themselves carry no known PFAS contamination risk, but the company does not independently verify this in public statements.
How it compares in its category
Refrigerator replacement filters from major manufacturers (Sub-Zero, GE, Whirlpool, Samsung) use similar activated carbon and ion-exchange resin constructions. Sub-Zero filters are mid-to-premium priced and typically rated for 6 months or 200 gallons of water. This product sits at the expected performance and safety baseline for manufacturer-supplied filters in the luxury appliance segment, with no meaningful differentiation in material hazard profile compared to competitors.
If you buy it
Replace the filter every 6 months or sooner if water flow decreases; stagnant filters can develop bacterial biofilm. Do not attempt to rinse and reuse the cartridge. Ensure the filter seats properly in the refrigerator to prevent bypass around the media. Store replacement filters in a cool, dry place away from direct sunlight to preserve resin function before installation.
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 if unmaintained
Activated carbon and resin can support microbial biofilm growth if the filter remains in use beyond its rated lifespan or if water stagnates in the cartridge housing. Regular 6-month replacement eliminates this risk.
Housing leachables from plastic components
Sub-Zero does not disclose the specific plastic polymer used in the filter housing. No recalls or contamination reports are on record for this model, and food-contact plastics in filter housings are typically regulated for migration limits by NSF or equivalent standards.
Ion-exchange resin degradation and particle shedding
Over extended use, resin beads can fracture and release small particles into water. This is rare in properly manufactured filters changed at recommended intervals, but degraded filters left in service beyond their rating increase this risk.
Contaminant breakthrough and water quality decline
This is not a safety hazard per se, but performance failure: as activated carbon becomes saturated, filtering effectiveness decreases. Water may taste or smell off before safety limits are crossed, but following the 6-month replacement schedule prevents this.
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 Refrigerator Filters
Kenmore
9690 Refrigerator Water Filter 1-Pack, Nsf/wqa/iapmo Certified, Reduces 99% Chlorine & Odor, BPA-Free, Replacement for 46-9690 469690 Lt700p
activated carbon filter cartridge
Lower-concern water filter; carbon-based design unlikely to contain PFAS, but Kenmore makes no explicit PFAS disclosure.
✓Verified PFAS-free by a third party
Kenmore
Pureline Filter Compatible with Whirlpool Everydrop Filter 1
Activated carbon and fiberglass filter media
Lower concern for PFAS; standard cartridge filter with no known PFAS-bearing materials, but brand offers no transparency.
✓Bare metal or glass, no coating at all
Clearly Filtered
Water Pitcher Replacement Filter 3-Pack
Activated carbon and ion-exchange resin filter media
Lower-concern option; activated carbon filters are standard PFAS-reduction media, but verify pitcher durability and actual tested removal rates independently.
✓Brand claims PFAS-free (unverified)
More refrigerator filters 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.