When a water filter manufacturer evaluates a new filter media for PFAS removal, the first question is always the same: “What’s the actual removal rate — and can you prove it?”
📚 New to PFAS? Start here: What Is PFAS? The “Forever Chemical” Every Water Filter Manufacturer Needs to Understand →
At BLUELABS, we answer that question with independent laboratory data. MARISORB™, our oyster-shell-derived PFAS adsorption media, has been tested in accordance with NSF/ANSI 53 standards — the benchmark for drinking water treatment claims.
In this article, we break down the test results, explain what drives MARISORB™’s superior performance, and discuss what these numbers mean for your OEM filter product line.
The Test Results: 6 PFAS Compounds, One Media
Independent NSF/ANSI 53-aligned testing was conducted across six of the most commonly regulated PFAS compounds. Here are the results:
| PFAS Compound | Full Name | Chain Length | MARISORB™ Removal Rate |
|---|---|---|---|
| PFOA | Perfluorooctanoic acid | Long-chain (C8) | ✓ 100% |
| PFOS | Perfluorooctane sulfonic acid | Long-chain (C8) | ✓ 100% |
| PFNA | Perfluorononanoic acid | Long-chain (C9) | ✓ 100% |
| PFDA | Perfluorodecanoic acid | Long-chain (C10) | ✓ 100% |
| PFHxS | Perfluorohexane sulfonic acid | Short-chain (C6) | ✓ 99.1% |
| PFHpA | Perfluoroheptanoic acid | Short-chain (C7) | ✓ 97.8% |
The range of 97.8–100% represents one of the highest consistently demonstrated removal rates for a single filter media across this compound set — and critically, it includes short-chain PFAS, which are notoriously difficult for conventional media to capture.
Why Short-Chain PFAS Is the Hard Part
PFAS compounds aren’t all equal from a filtration standpoint. Long-chain PFAS (C8 and above) like PFOA and PFOS have been regulated for years and most activated carbon filters handle them reasonably well.
Short-chain PFAS — such as PFHxS (C6) and PFHpA (C7) — present a fundamentally different challenge:
- Lower hydrophobicity: Short-chain compounds are more water-soluble and less attracted to carbon surfaces
- Faster breakthrough: They “slip through” activated carbon beds much sooner than long-chain variants
- Growing regulatory focus: The U.S. EPA’s 2024 PFAS National Primary Drinking Water Rule specifically includes PFHxS alongside PFOA and PFOS
Standard granular activated carbon (GAC) performs adequately against long-chain PFAS but often struggles at trace concentrations of short-chain variants. This is where MARISORB™’s unique surface chemistry delivers its most significant advantage.
MARISORB™ vs. Activated Carbon: Breakthrough Point Comparison
Filter lifetime is measured in gallons treated before the media reaches its breakthrough point — the threshold where filtered water no longer meets the target purity standard. Here’s how MARISORB™ compares to standard activated carbon for short-chain PFAS:
| Media | Short-Chain PFAS Breakthrough | Long-Chain PFAS Breakthrough | Relative Short-Chain Performance |
|---|---|---|---|
| Activated Carbon (GAC) | Baseline | Baseline | — |
| MARISORB™ | 5× longer | Comparable or better | ✓ 5× superior |
In practical terms: if your current activated carbon filter replaces every 200 gallons for adequate PFAS protection, MARISORB™-based media can extend that to ~1,000 gallons under equivalent conditions for short-chain PFAS targets. This translates directly to:
- Lower lifetime cost for end consumers
- Fewer replacements and reduced packaging waste (ESG story)
- Stronger product differentiation for OEM partners
The Science: Why Oyster Shell Works
MARISORB™ is derived from upcycled oyster shells collected from aquaculture operations in Tongyeong, South Korea — a region that generates tens of thousands of tonnes of oyster shell waste annually.
Through BLUELABS’ proprietary processing technology, the calcium carbonate structure of oyster shells is engineered to create a high-surface-area adsorption matrix with dual removal capability:
1. Electrostatic Adsorption (PFAS)
PFAS molecules carry a negatively charged fluorinated tail. MARISORB™’s engineered surface presents positively charged adsorption sites that attract and bind PFAS compounds — including short-chain variants — through electrostatic interaction. This mechanism is more effective than the purely hydrophobic adsorption mechanism of standard carbon.
2. Ion Exchange + Precipitation (Heavy Metals)
The calcium-rich oyster shell matrix provides a natural ion exchange surface for heavy metal cations (Pb²⁺, Cd²⁺, Cu²⁺, etc.). This enables simultaneous PFAS and heavy metal removal — a dual-action capability that no single activated carbon product matches.
Key insight for OEM engineers: MARISORB™’s removal mechanism is additive, not competitive. Treating water with both PFAS and heavy metal contamination doesn’t reduce efficiency for either — both removal pathways operate independently.
Regulatory Compliance: NSF/ANSI 53 and What It Means
NSF/ANSI 53 is the gold standard for point-of-use water treatment devices making health claims in North America. While full NSF/ANSI 53 certification applies to complete filter systems (not raw filter media), BLUELABS’ testing protocol is conducted in accordance with NSF/ANSI 53 challenge test methodology, meaning:
- Challenge water is prepared at standardized PFAS concentration (inlet: 150 ppt per compound)
- Flow rate and contact time replicate real-world filter conditions
- Outlet samples are analyzed by accredited third-party laboratory
- Results are reproducible across multiple production batches
OEM partners can use BLUELABS’ test data as a foundation for their own system-level NSF/ANSI 53 certification applications. We provide complete documentation packages upon request under NDA.
How Removal Rate Translates to Product Specs
For filter product development, raw removal rate data needs to be translated into meaningful consumer-facing specifications. Here’s how MARISORB™’s performance maps to typical product claims:
| Product Claim | Data Requirement | MARISORB™ Status |
|---|---|---|
| “Removes PFOA and PFOS” | ≥95% reduction | ✓ 100% documented |
| “Reduces 6 PFAS compounds” | ≥80% for each compound | ✓ 97.8–100% |
| “NSF/ANSI 53 compliant testing” | Third-party protocol adherence | ✓ Completed |
| “Removes heavy metals” | Pb, Cd, Cu reduction data | ✓ Available |
Comparison with Competing PFAS Filter Media
To put MARISORB™’s performance in competitive context, here’s a comparison with publicly available data from category leaders:
| Media Type | PFAS Compounds Removed | Short-Chain Performance | Heavy Metal Removal | ESG Story |
|---|---|---|---|---|
| MARISORB™ | 6 (97.8–100%) | Excellent (5× vs. GAC) | Yes (simultaneous) | Oyster shell upcycle (circular economy) |
| Pentair PFAS media* | 5 (varies) | Limited data published | No | Virgin synthetic |
| Standard GAC | 2–4 (variable) | Poor | Minimal | Mined/processed coal |
| Ion Exchange Resin | 4–6 (high) | Good | No | Synthetic polymer |
*Based on publicly available Pentair product sheets (EVERPURE QC7i-PFAS). MARISORB™ performance data from BLUELABS independent laboratory testing, 2024.
OEM Integration: What You Need to Know
MARISORB™ is available in multiple form factors for OEM integration:
- Loose media (granular): For custom-fill cartridges and tank applications
- Block format: For 10-inch and 20-inch standard housing integration
- Blended media: Can be combined with GAC, KDF, or other media for multi-stage applications
Minimum order quantities, pricing, and sample requests are available directly from BLUELABS’ B2B team. Current OEM references include Wako Corporation and Yukyung Bio, both of which have independently verified MARISORB™ performance in their product development pipelines.
Bottom Line
MARISORB™ achieves 97.8–100% removal across 6 PFAS compounds in NSF/ANSI 53-aligned testing. Its most distinctive advantage lies in short-chain PFAS handling — where it delivers 5× the breakthrough resistance of standard activated carbon — combined with simultaneous heavy metal removal and a circular economy ESG story.
For OEM water filter manufacturers building next-generation PFAS-compliant products, that combination is hard to replicate with conventional media.
Request Test Data & OEM Samples
Full laboratory test reports, batch-specific performance data, and OEM media samples are available to qualified water filter manufacturers under NDA. Contact BLUELABS to start the conversation.