GL Sciences FM4 Air Sampler for PFAS

The GL Sciences FM4 Air Sampler for PFAS is a low-volume air sampling system designed for the collection of per- and polyfluoroalkyl substances (PFAS) in ambient air. The instrument enables the simultaneous sampling of both particulate and gaseous PFAS within a single operation, supporting a more comprehensive assessment of atmospheric PFAS contamination. PFAS comprise a large group of synthetic fluorinated compounds widely used for their chemical stability, thermal resistance and surfactant properties. Due to their persistence in the environment and potential health impacts, several PFAS are now regulated under international frameworks such as the Stockholm Convention on Persistent Organic Pollutants. Despite this, data on PFAS concentrations in air remain limited, highlighting the need for reliable analytical approaches to characterise their presence and behaviour in the atmosphere.

Conventional filtration-based sampling methods can lead to analytical uncertainty, as gaseous PFAS may adsorb onto particles collected on filter surfaces or undergo chemical transformation during sampling. The FM4 addresses these limitations through a sampling design incorporating an impactor stage that minimises interaction between particles and gas phases, combined with multiple sorbent materials for selective capture of different PFAS types. The system also utilises a functional activated carbon sorbent (GAIAC), based on synthetic resin fibres with controlled pore structure and surface activity, which supports efficient adsorption and solvent elution of gaseous PFAS. Following sampling, collected compounds can be extracted with organic solvents and analysed using techniques such as GC-MS/MS and LC-MS/MS.