Tackling forever chemicals

Enzyme strategies for PFAS hotspots

Per‑ and polyfluoroalkyl substances (PFAS) are an environmental challenge that has steadily shifted from scientific discourse into boardrooms, council chambers and community meetings. Their unusual chemistry—defining persistence, mobility and bioaccumulative potential—creates complex, long‑tail risks across soils, leachates, wastewater, industrial effluents and receiving waters. In the UK, the PFAS landscape is highly heterogeneous: high‑impact, legacy hotspots sit alongside diffuse, low‑concentration exposures. Remediation options have grown in sophistication, yet truly destructive, cost‑effective solutions at scale remain elusive. Amid this evolving toolkit, enzymes and enzyme‑informed hybrid trains are emerging as practical, targeted instruments for mitigation—particularly when integrated with capture technologies and lower‑dose oxidation methods.

This article reviews the UK hotspot context and explores how enzyme‑catalysed and hybrid approaches can mitigate risk in soils, leachates and industrial effluents, alongside robust source control. It positions BioGlobe’s discovery‑to‑pilot capability for bespoke enzyme identification, engineering and field validation. Throughout, we discuss what is realistic in the near term, where enzymes add compelling value, and where complementary technologies remain essential.

Executive summary

• PFAS contamination is widespread but uneven, with UK hotspots concentrated around airports, Ministry of Defence (MoD) and firefighting training sites, landfills, textile and metal finishing clusters, and wastewater treatment works. The mixture of legacy long‑chain PFAS and contemporary short‑chain alternatives complicates capture and treatment.
• Enzyme‑catalysed processes can selectively transform certain PFAS subclasses or their precursors under mild conditions, improving downstream capture efficiency and, in some cases, enabling stepwise defluorination. The most credible near‑term deployments are hybrid systems—enzyme plus adsorption and/or oxidation—to reduce chemical and energy demand while improving overall performance.
• BioGlobe is building a pipeline from metagenomic discovery to immobilisation science and modular pilot skids, enabling targeted enzyme solutions for specified PFAS fingerprints. Early pilots should prioritise ex situ side‑streams such as landfill leachates and industrial effluents, with rigorous monitoring of fluoride release, PFAS subclass shifts and total oxidisable precursor (TOP) assay responses. Complementary technologies remain critical for capture, concentration and residual destructive polishing.

1) The UK PFAS hotspot landscape

PFAS are not a single compound but a family of thousands of fluorinated organics with diverse headgroups, chain lengths and architectures (including ether linkages and fluorotelomer backbones). Their applications range from aqueous film‑forming foams (AFFF) and industrial surfactants to water‑ and stain‑resistant coatings in textiles, carpets, paper and packaging. The UK’s PFAS signature reflects decades of usage patterns and regulatory transitions.

Where PFAS show up

• Airports and MoD sites: Historic AFFF use has produced localised but significant impacts in soils and groundwater, particularly around fire training areas and hangars. Long‑chain PFAS such as PFOS and PFOA, though increasingly regulated and phased out, persist in the subsurface. Newer foams tend to incorporate shorter‑chain PFAS and precursors, which are more mobile and harder to capture with conventional sorbents.
• Firefighting training grounds (civilian and defence): Repeated, high‑intensity releases over decades create concentrated source zones in the vadose zone, with rainfall events driving episodic pulses to surface waters. PFAS plumes can show complex temporal patterns, reflecting precursor conversion and variable infiltration.
• Landfills and waste transfer stations: Landfill leachate often contains a broad mixture of PFAS derived from consumer products and industrial residues. Concentrations and fingerprints vary by waste profile and age, with high dissolved organic carbon (DOC), surfactants, ammonia and metals adding competitive effects and fouling risks for capture media.
• Industrial clusters: Electroplating, metal finishing, textile finishing, paper/packaging coaters, semiconductors and fluoropolymer supply chains show diverse PFAS signatures. Effluents may be intermittent but compositionally consistent, making them suitable candidates for tailored, side‑stream interventions.
• Wastewater treatment works (WWTWs): Conventional biological treatment removes little PFAS and can transform precursors, shifting the fingerprint rather than eliminating the fluorinated burden. PFAS partition variably between effluent and biosolids, raising issues for land application of sludge and downstream polishing requirements.

Regulatory and liability context

Regulatory tightening is ongoing in the UK and Europe. Guidance values have moved lower over time, and utilities face increasingly strict oversight for drinking water supplies and discharges. The “short‑chain problem” is prominent: while short‑chain PFAS may be less bioaccumulative, they are more mobile and frequently elude granular activated carbon (GAC) at practical empty‑bed contact times. Ion exchange (IX) resins improve capture of short‑chains, but regeneration creates brines that require destructive treatment or costly off‑site management. Asset owners therefore seek trains that are defensible, lifecycle‑cost‑optimised and measurable against clear performance metrics.

Practical implication: triage and fingerprinting

Triage should combine hydrogeology, PFAS speciation (including precursors and short‑chains), co‑contaminant profiles (DOC, surfactants, ammonia, metals), and an understanding of source persistence (ongoing inputs vs legacy). This informs which hybrid trains are viable and where enzymes can add value—either by transforming precursors into more easily captured species, extending media life, or enabling partial defluorination ahead of a lower‑intensity destructive step.

2) Why enzymes for PFAS?

The chemical challenge

The carbon‑fluorine bond in PFAS is famously strong, with bond dissociation energies often exceeding 100 kcal/mol. Many PFAS structures also resist oxidative and reductive conditions that would cleave other organofluorines. Meanwhile, precursors can convert to perfluoroalkyl acids during treatment, sometimes making effluent PFAS appear stable or even worse unless analytical methods capture the full precursor burden (e.g., TOP assay).

Abiotic destructive technologies—oxidation, reduction or plasma—can achieve high levels of mineralisation in some matrices, but energy and reagent costs can be substantial, and by‑products require verification. Capture technologies can be effective but shift the waste burden into spent media or brines that must be handled, often at significant expense.

The enzymatic opportunity

Enzymes offer three primary benefits in the PFAS context:

• Selectivity: Enzymes can recognise and act on specific headgroups, side chains or weak points (e.g., sulfonamido linkages, ether linkages, telomer precursor moieties). Even when they do not fully mineralise PFAS, they may convert precursors to terminal acids that are easier to capture, or introduce labile functionalities that render subsequent oxidation more efficient.
• Milder conditions: Enzymatic reactions generally operate at ambient temperatures, near‑neutral pH and without large reagent burdens. This can lower operational costs and reduce safety concerns associated with strong oxidants or high voltage systems.
• Integrability: Enzymes can be deployed as free catalysts for polishing, immobilised on supports for reuse, or expressed in whole‑cell systems, enabling flexible integration into existing treatment trains.

Evidence from the literature shows that oxidative enzymes (e.g., peroxidases, laccases) and reductive biocatalysts (e.g., dehalogenase‑like activities, ene‑reductases in specific contexts) can achieve precursor transformation and partial defluorination on certain PFAS analogues under controlled conditions. While not a universal solution, these activities suggest a role for enzymes as performance enhancers within hybrid systems that combine capture and lower‑dose destructive polishing.

Delivery formats

• Free enzymes in solution: Useful for batch contactors or continuously stirred reactors polishing side‑streams. Advantages include flexibility and ease of dosing; drawbacks include potential washout and shorter operational life.
• Immobilised enzymes: Anchored to biochar, ceramics, polymer beads or membranes, immobilised enzymes resist washout, can be reused and sometimes gain stability. Supports can be chosen to co‑sorb PFAS, coupling transformation with concentration at the interface.
• Whole‑cell or consortia: Engineered microbes or consortia expressing relevant enzymes can add robustness and in situ regeneration of activity. However, regulatory and biosafety considerations may limit deployment in certain settings, and matrix toxicity can restrict performance.

3) Hybrid trains: combining enzyme catalysis with capture and oxidation

The most credible pathway for near‑term value is to pair enzymatic steps with established technologies in a way that reduces overall cost, waste and risk.

Enzyme + adsorption (GAC/IX)

Use case: Reduce dissolved PFAS load and transform precursors before adsorptive capture, thereby extending media life and improving capture of short‑chains.

• Process concept: An enzyme contactor upstream of GAC or IX can convert a portion of precursors into terminal acids that bind more strongly, or partially defluorinate select compounds, reducing breakthrough. Immobilised enzymes on sorbent supports can promote reaction at the solid–liquid interface where PFAS concentrate, offering mass transfer advantages.
• Operational notes: Monitor TOP assay responses and subclass‑specific concentrations to verify that reductions in parent species are not offset by increased terminal acids. Track pressure drop and fouling on immobilised beds, and plan for periodic cartridge swaps or regeneration.

Enzyme + advanced oxidation

Use case: Enzymatic “pre‑conditioning” introduces labile functionalities or decreases electron density on PFAS backbones or precursors, making subsequent low‑dose oxidation more effective.

• Process concept: Enzyme contactor followed by UV/peroxide, UV/sulfite, persulfate activation, or electro‑oxidation operated at reduced energy or reagent doses compared with oxidation alone. By tempering oxidant demand, OPEX can be reduced and by‑product formation limited.
• Operational notes: Carefully measure fluoride release and identify partial defluorination products. Optimise pH, radical species and residence time. Closed‑loop control using fluoride ion‑selective electrodes and LC‑MS/MS can improve stability.

Enzyme + foam fractionation

Use case: In matrices with surfactants (leachates, firewater, some industrial effluents), foam fractionation concentrates PFAS, enabling smaller‑volume, higher‑efficiency treatment.

• Process concept: First, use foam fractionation to generate a PFAS‑rich concentrate. Then apply enzymatic treatment to the concentrate to convert precursors and soften the mixture ahead of destructive polishing. The aim is to shrink disposal volumes or reduce the intensity of the final destructive step.
• Operational notes: The presence of surfactants can impact enzyme activity. Pre‑conditioning to remove enzyme inhibitors may be needed. Immobilisation can help maintain activity in a foamy, high‑interfacial‑area environment.

Solids management: coupling capture and catalysis

Immobilising enzymes on sorbents such as biochar, functionalised polymer resins or ceramic foams can co‑locate transformation and capture. This approach reduces enzyme loss, simplifies handling, and can be configured in modular cartridges. It is especially attractive for side‑stream polishing skids where maintenance windows are predictable.

Monitoring and verification across hybrid trains

Performance must be evaluated beyond simple concentration declines in a handful of PFAS. Key monitoring elements include:

• TOP assay: To quantify precursors and confirm net reduction of oxidisable fluorinated species.
• Fluoride release: As a proxy for defluorination; requires ion chromatography or fluoride ion‑selective electrodes with appropriate quality controls.
• LC‑MS/MS panels including short‑chains: To detect shifts down the chain length spectrum and avoid misinterpreting apparent removal.
• LC‑HRMS for discovery: To identify unknown transformation products during R&D and pilot phases.
• Mass balance on fluorine: While challenging, attempts to close the fluorine budget reduce the risk of “phantom removal”.

4) Near‑term applications by matrix

Different matrices present distinct constraints and opportunities. Below are realistic application concepts for the next 12–24 months.

Landfill leachate (ex situ)

Challenges: High DOC, variable PFAS mixtures spanning long‑ and short‑chains, surfactants, ammonia, metals, and seasonal flow variability. Leachates often include inhibitors for both enzymes and oxidation processes. IX resins can capture many PFAS species but produce brines requiring destruction or shipment.

Strategy:

• Front‑end screening to map the PFAS fingerprint, inhibitors and co‑contaminant loads.
• Enzymatic pre‑treatment targeting prevalent precursors and specific transformable species. Immobilised formats can help maintain activity within complex matrices.
• Follow with IX for bulk PFAS capture. Expect extended bed life if precursor conversion reduces competitive breakthrough and if partial defluorination improves binding.
• Apply destructive polishing to IX regenerant brine or RO concentrate using electro‑oxidation or UV‑based methods at reduced intensity, leveraging the enzymatic pre‑conditioning.
• Employ foam fractionation where surfactants and long‑chain PFAS enable effective concentration; treat the foamate with enzymes plus oxidation to reduce final disposal demand.

Key performance indicators (KPIs): Reduction in ∑PFAS, TOP assay delta, fluoride release, IX bed‑life extension, reagent/energy demand per m³, and waste volume reduction.

Industrial effluents (side‑stream, ex situ)

Targets: Metal finishing and plating rinse waters, textile finishing effluents, fluorochemical intermediates and coating lines. These streams often show repetitive fingerprints and predictable flow windows—ideal for tailored enzyme solutions.

Strategy:

• Characterise the FPAS profile to identify dominant precursors, headgroups and chain length distributions.
• Deploy immobilised enzyme contactors in recirculating skids with modest residence times. Design for quick cartridge change‑out and on‑site regeneration where feasible.
• Integrate with existing pre‑treatment (pH control, solids removal) and downstream capture (IX/GAC) or concentration (RO). For specific cases, enzyme pre‑conditioning enables lighter‑touch oxidation for destructive polishing.
• Build feedback loops with analytics to stabilise performance and ensure permit compliance.

KPIs: TOP‑to‑terminal conversion, fluoride release where applicable, reduction in permit exceedances, lower frequency of sorbent change‑outs, reduced off‑site disposal requirements and OPEX per unit PFAS removed.

Soils and vadose zone at firefighting training sites

Reality check: In situ enzymatic delivery to heterogeneous soils is technically challenging due to sorption, diffusion limitations, enzyme instability and competing reactions. Water content and redox conditions vary spatially, inhibiting consistent catalysis.

Pragmatic approach:

• Identify “hot pockets” for selective excavation, avoiding mass earthworks where possible.
• Apply soil washing to transfer PFAS into an aqueous phase. Treat wash water via enzyme‑informed hybrids (enzyme + foam fractionation + IX + low‑dose oxidation). This allows controlled conditions and recyclable wash solutions.
• Manage residual soils via capping, targeted in situ chemical oxidation (ISCO) where evidence supports effectiveness, and robust stormwater control to prevent episodic releases.

KPIs: PFAS removal from wash water, reduction in residual soil leachability, fluoride balance during water treatment, and cost per tonne of soil treated.

Wastewater treatment works (WWTWs)

Near‑term focus: Rather than whole‑plant flows, target side‑streams and concentrates where PFAS are elevated and volumes manageable—e.g., reverse osmosis concentrates, sidestream centrates or certain industrial co‑treatment inflows.

Strategy:

• Use enzyme‑assisted polishing in dedicated side‑stream skids to reduce PFAS prior to mixing with main plant flows or prior to final discharge.
• Explore immobilised enzyme modules upstream of IX, aiming to extend resin life and improve removal of short‑chains.
• For solids, address biosolids recycling implications through separate risk assessments; enzyme strategies are less suited to direct treatment of sludge‑bound PFAS at present.

KPIs: Side‑stream PFAS reduction, cost per kg PFAS addressed, media life extension and contribution to overall works compliance.

5) Where enzymes fit—and where they do not

It is critical to position enzymes realistically, avoiding “silver bullet” narratives and focusing on integration, measurement and risk reduction.

Good fits:

• Defined, repetitive PFAS fingerprints, especially in industrial side‑streams where tailored enzymes can be matched to dominant compounds and precursors.
• Concentrated streams post‑capture, such as IX brines, RO concentrates or foamate, where volumes are low and gains in oxidation efficiency translate into real OPEX savings.
• Precursor‑rich matrices where enzymatic conversion to terminal acids improves downstream capture and lowers total treatment cost.

Harder fits:

• Highly dilute, variable municipal effluents without a concentration step—enzyme demand and contact time become impractical.
• Heterogeneous soils for in situ treatment—mass transfer and stability constraints dominate.
• Scenarios demanding immediate, near‑complete mineralisation at large scale—current enzymatic systems are more suited to transformation and partial defluorination as part of a train.

Risk management:

• Define success in operational terms: fewer permit exceedances, longer sorbent life, reduced brine volumes, lower energy and chemical use, verified fluoride release and improved mass balance.
• Bake in analytical rigor from the outset, including TOP assay and HRMS during R&D and early pilots to avoid hidden failure modes.

6) BioGlobe’s R&D and pilot pathway

BioGlobe’s approach is to link discovery science with field‑ready engineering in a rapid, iterative loop. The aim is to generate bespoke enzyme solutions for specific PFAS fingerprints and matrices, then validate them under real‑world conditions.

Discovery and design

• Metagenomic mining: Targeted sampling from PFAS‑impacted environments—landfill leachate biomes, fire training soils, industrial effluent biofilms—to search for hydrolases, oxidoreductases and novel catalysts that act on PFAS headgroups, precursors or specific weak points in the molecules.
• Enzyme engineering: Use structure‑guided and directed evolution techniques to tune active sites for selectivity, activity and stability in relevant pH, ionic strength and surfactant backgrounds. Optimise co‑factors and mediators where needed, balancing efficacy and cost.
• Immobilisation science: Select and functionalise supports (biochar, ceramic foams, polymer beads, membranes) to bind PFAS and align reactants at the catalyst interface. Design for mechanical stability, low pressure drop and straightforward change‑outs.

Screening and analytics

• High‑throughput microplate assays: Rapidly screen enzyme variants against site‑specific matrices, not just clean water, to capture inhibitor effects. Use realistic PFAS mixtures to avoid over‑optimistic results.
• LC‑MS/MS panels and TOP assay: Track parent compounds, short‑chains and precursors. Calculate ∑PFAS and subclass patterns before and after treatment.
• Fluoride monitoring: Use ion‑selective electrodes or ion chromatography, with calibration and recovery checks. A credible fluoride signal supports claims of defluorination.
• HRMS for unknowns: During discovery and pilot work, deploy high‑resolution mass spectrometry to detect intermediates and avoid shifting risk into unmonitored species.

Pilot design and deployment

• Modular skids (10–200 L/h): Enzyme contactor → capture (IX/GAC) → destructive polishing (electro‑oxidation or UV‑based) with integrated analytics. Skids are designed for plug‑and‑play on side‑streams such as leachate slipstreams or industrial rinse lines.
• Site selection: Focus on UK hotspots with clear liability drivers, access to representative matrices, and measurable success criteria (permits, OPEX, media life).
• Data and control: On‑skid sensors for flow, pressure, pH, ORP and fluoride; sampling ports for LC‑MS/MS and TOP assay; digital logging to generate robust datasets for techno‑economic assessment (TEA).

Commercialisation milestones

• Bench: Achieve conversion of targeted precursors and partial defluorination in real matrices; demonstrate immobilised stability over realistic timeframes; develop clear dose–response curves.
• Pilot: Run 100–500 hour continuous trials; confirm fluoride mass balance within acceptable error; quantify IX/GAC life extension; measure energy and chemical savings in destructive polishing.
• Scale‑out: Replicate pilots across multiple sites; formalise operating windows and maintenance cycles; refine cost models and supply chains for enzyme cartridges.

Positioning statement:

BioGlobe provides bespoke enzyme discovery and engineering aligned to the exact PFAS mix and co‑contaminants at a given site, integrating catalysts with proven capture and oxidation steps to deliver measured risk reduction at lower lifecycle cost.

7) Measurement, verification and economics

PFAS treatment claims are frequently undermined by incomplete analytics. A rigorous measurement framework is non‑negotiable, particularly when introducing novel catalytic steps.

Metrics that matter

• ∑PFAS reduction by subclass: Not just headline compounds; include short‑chains and relevant precursors.
• TOP assay delta: A reduction in oxidisable precursors indicates genuine progress, while increases signal hidden liability.
• Fluoride release: Molar fluoride recovery is a key indicator of defluorination. While complete closure of the fluorine balance is challenging, measured release in line with observed concentration changes builds confidence.
• Media life extension: For IX/GAC, quantify the shift in breakthrough curves and change‑out intervals.
• Energy and chemicals per ng PFAS removed: A unifying metric to compare oxidation strategies with and without enzymatic pre‑conditioning.
• Waste volume reduction: Track brine and foamate volumes, spent media mass, and off‑site disposal needs.

Data quality objectives (DQOs)

• Sampling discipline: Triplicates at critical points, field blanks, matrix spikes, and internal/surrogate standards for LC‑MS/MS.
• Mass balance mindset: Define a fluorine balance approach early, including limits of detection and uncertainty ranges.
• Stability testing: Evaluate enzyme activity decay in matrix, the impact of fouling and shearing, and performance recovery after backwashing or mild regeneration.

Techno‑economic assessment (TEA) levers

• Enzyme and mediator costs vs oxidant and power costs: Enzyme cartridges can deliver savings by reducing the scale of destructive polishing.
• Sorbent life and change‑out frequency: Media extension multiplies savings through avoided material, labour and downtime.
• Concentration step efficiency: Foam fractionation or RO that halves final destructive polishing demand can swing the economics decisively.
• Modular CAPEX: Small, relocatable skids reduce capital risk and enable flexible deployment across sites.

8) Roadmap: realistic timelines and expectations

A sensible adoption curve builds credibility and value without overpromising.

• 0–12 months:
  • Site‑specific matrix collection (5–10 L per site stream) and fingerprinting.
  • Bench screening of enzyme variants on real matrices; immobilisation down‑selection; demonstration of precursor conversion and partial defluorination (e.g., 10–30% on targeted subclasses under optimised conditions).
  • Column tests showing 20–50% IX/GAC bed‑life extension in spiked and real matrices.
• 12–24 months:
  • Field pilots on landfill leachate slipstreams and industrial rinse waters at 10–200 L/h.
  • Integrated hybrid operation with on‑skid analytics; fluoride mass balance closure within an agreed tolerance.
  • TEA demonstrating ≥20% OPEX reduction vs capture‑only or oxidation‑only baselines.
• 24+ months:
  • Replication at multiple UK hotspots; formal operating envelopes for different matrix classes.
  • Engagement with regulators to translate pilot data into consent conditions and long‑term compliance strategies.
  • Continuous improvement via enzyme evolution, improved immobilisation supports and smarter control systems.

Expectations should remain grounded: enzymes are powerful tools when pointed at the right targets in the right trains, not all‑purpose destroyers. By focusing on measurable gains—especially in precursor conversion, media life and polishing efficiency—site owners can de‑risk capital decisions and build towards fuller mineralisation where justified.

9) Complementary technologies you will likely still need

Even as enzyme capabilities grow, a robust PFAS treatment programme typically includes multiple unit operations. Selecting and sequencing them is the heart of practical engineering.

• Capture:
  • Ion exchange (IX): Strong performers for short‑chain PFAS; regeneration produces brines that benefit from destructive polishing. Resin choice matters for fouling and selectivity.
  • Granular activated carbon (GAC): Effective for long‑chains and hydrophobic species; less effective for short‑chains at practical residence times. Often used as a polishing layer.
  • Foam fractionation: Particularly effective for concentrate generation in surfactant‑rich streams and firewater; a valuable pre‑treatment to shrink downstream volumes.
  • Reverse osmosis (RO): High removal across PFAS classes; creates concentrates that must be managed destructively but enables small‑volume, high‑efficiency treatment.
• Destruction:
  • Electro‑oxidation: Effective on concentrates and brines; OPEX and electrode robustness are key variables. Enzymatic pre‑conditioning can reduce energy per unit fluorine removed.
  • UV‑based oxidation/reduction (e.g., UV/sulfite, UV/peroxide, persulfate activation): Useful for destructive polishing; careful control of radical species and pH is needed.
  • Plasma and catalytic reduction: Options for specific use‑cases and concentrates; by‑product control and power costs must be managed.
• Source control:
  • AFFF management: Replace legacy foams, upgrade containment, and institute rigorous handling and training protocols.
  • Industrial substitution: Reformulate where practicable; improve housekeeping to minimise fugitive releases.
  • Landfill water controls: Cover integrity, leachate collection optimisation, stormwater separation to reduce hydraulic loads.
  • Soil management: Targeted excavation, capping and water routing to prevent episodic mobilisation.

10) Case‑style scenarios and design notes

To bring the concepts together, consider three simplified scenarios illustrating how enzyme‑informed hybrids might be configured.

Scenario A: Landfill leachate with high DOC and mixed PFAS

• Observations: ∑PFAS at mid mg/L, strong TOP signal indicating precursors, significant short‑chain presence, DOC > 100 mg/L, variable surfactants.
• Train design:
  • Foam fractionation to generate a PFAS‑rich concentrate and reduce DOC load in the main stream.
  • Immobilised enzyme contactor treating the concentrate to convert precursors and facilitate subsequent oxidation.
  • Electro‑oxidation of the treated concentrate at reduced current density; parallel IX polishing of the main stream with less frequent regeneration.
• Outcomes to target: 25–40% reduction in oxidant or power demand for the destructive step, 30–50% extension in IX media life, reduced concentrate volume for off‑site management.

Scenario B: Plating shop rinse water with stable fingerprint

• Observations: Predictable production cycles, PFAS concentrations in tens to hundreds of µg/L, consistent fluorotelomer precursors.
• Train design:
  • Immobilised enzyme module in a recirculating skid; short residence time but multiple passes during production runs.
  • Downstream IX column for capture with extended breakthrough interval.
  • Small UV‑based destructive polishing unit for occasional regenerant brine.
• Outcomes to target: Reliable discharge compliance, fewer IX change‑outs, and a measurable reduction in OPEX per kg PFAS managed.

Scenario C: Fire training site soil washing

• Observations: High PFAS in soils near training pads; logistical constraints preclude wholesale excavation.
• Train design:
  • Selective excavation of hot zones; soil washing with closed‑loop water.
  • Enzyme‑assisted treatment of wash water combined with foam fractionation and IX; low‑dose oxidation for final polishing.
  • Reuse of treated wash water to minimise fresh water input and waste.
• Outcomes to target: Reduced leachability in returned soils, constrained waste volumes, defensible mass balance for project close‑out.

11) Implementation checklist for asset owners and consultants

• Baseline characterisation:
  • Collect representative samples across seasons if flows vary.
  • Quantify PFAS subclasses, short‑chains and precursors; run TOP assay.
  • Identify potential enzyme inhibitors (e.g., oxidants, surfactants, metals) and matrix conditions (pH, ionic strength).
• Feasibility screening:
  • Submit 5–10 L of matrix for bench enzyme screening and immobilisation trials.
  • Compare enzyme‑informed vs conventional capture and oxidation in side‑by‑side tests.
• Pilot plan:
  • Define clear KPIs: compliance thresholds, OPEX targets, media life, fluoride balance.
  • Select a modular skid size (10–200 L/h) aligned to a side‑stream with stable flow.
  • Establish sampling and QA/QC protocols before mobilisation.
• Operations:
  • Set up real‑time or frequent fluoride monitoring.
  • Implement cartridge change‑out and resin regeneration schedules informed by analytics.
  • Maintain logs for energy, chemical dosing, flow and pressure for TEA updates.
• Review and scale:
  • After 100–500 hours, evaluate performance against KPIs.
  • Update lifecycle cost models; plan scale‑out or train optimisation as warranted.

12) Frequently asked questions (FAQs)

1. Are enzymes capable of fully destroying PFAS on their own?

• Today, full mineralisation of diverse PFAS solely via enzymes at practical scales is not realistic. However, enzymes can transform specific precursors, introduce labile sites and, in some cases, achieve partial defluorination. Their most effective role is within hybrid trains that include capture and a lower‑intensity destructive step. This integration reduces overall energy and chemical demand while improving measurable outcomes like media life and waste minimisation.

2. How do we know enzymatic treatment is truly working and not just shifting the PFAS profile?

• Robust analytics are vital. Alongside standard LC‑MS/MS panels, run TOP assays to capture precursors and track any net reduction in oxidisable fluorinated species. Monitor fluoride release quantitatively as evidence of defluorination, and deploy high‑resolution MS during R&D and pilots to detect and evaluate transformation products. Establishing a fluorine mass balance within a defined uncertainty range helps avoid “phantom removal”.

3. What matrices are the best early candidates for enzyme‑informed treatment?

• Side‑streams with stable and well‑defined PFAS fingerprints are best—industrial rinse waters and landfill leachate concentrates (from foam fractionation or RO) are prime examples. These streams allow tailored enzyme selection, manageable volumes and predictable operating windows. Highly dilute, variable municipal effluents without concentration steps are less suitable for initial deployments.

4. Will enzymes survive in harsh matrices with surfactants, metals or high DOC?

• Stability depends on enzyme choice, immobilisation and operating conditions. Immobilised enzymes on robust supports often show improved resilience and can be protected from inhibitors by pre‑conditioning steps. Bench screening using the real site matrix is essential to reveal compatibility issues. In practice, pre‑treatments such as foam fractionation or solids removal can significantly improve the enzymatic operating environment.

5. How should success be defined for an enzyme‑informed PFAS project?

• Success should be defined through measurable, risk‑relevant KPIs: reduction in ∑PFAS and precursor burden (TOP assay), verified fluoride release aligned with observed concentration changes, extension of capture media life, reduced volume or intensity of destructive polishing, lower waste disposal needs and overall OPEX reduction. These metrics align technical performance with regulatory compliance and lifecycle cost objectives.

Closing note

The UK faces a multi‑decade challenge in managing PFAS risks across a varied portfolio of sites and infrastructures. Enzyme‑catalysed strategies are not a panacea, but they are a timely addition to the toolkit—particularly when thoughtfully integrated with capture and oxidation. By focusing on side‑stream interventions, rigorous analytics, and iterative pilots, asset owners can achieve practical, defensible improvements today while building a foundation for broader adoption as the science and engineering mature.

BioGlobe’s proposition is to bridge discovery and deployment: identifying bespoke enzymes for site‑specific PFAS fingerprints, engineering them for stability and performance in real matrices, and validating their value in targeted field pilots. The outcome is not just concentration declines, but a verifiable reduction in risk and cost, with a clear path to scale.