Environmental laboratories are under growing pressure to deliver high-quality PFAS data while keeping pace with rising sample volumes, labor shortages, and increasingly complex regulatory requirements. Among the most challenging tasks is the extraction of PFAS compounds from solid matrices such as soils, sediments, and biosolids, an essential but time-consuming step that directly affects analytical quality and turnaround time.
A new application study demonstrates that the Milestone ETHOS X microwave extraction system, equipped with the XTR-44 rotor, provides a powerful alternative to the traditional shaker-table extraction method described in EPA 1633A. The research, carried out by Advanced Environmental Laboratories (AEL), compares conventional extraction with microwave-assisted extraction, highlighting major gains in efficiency, consistency, and analytical performance.
EPA Method 1633A allows laboratories to optimize extraction parameters under Section 9.1, opening the door to workflow improvements without compromising regulatory acceptance. Microwave-assisted extraction follows the same principles as the original method but eliminates repeated transfers, long agitation steps, and the risk of analyte loss. The ETHOS X achieves full extraction in only 15 minutes, reducing total sample-prep time by up to 70%, significantly lowering labor needs, and simplifying onboarding for new operators.
In our study, three soil matrices were processed in triplicate with both techniques. Results show excellent comparability across all 40 target PFAS analytes, with microwave extraction consistently matching or outperforming shaker-table values. Precision was maintained across replicates, and PT data for a certified reference soil fell well within method-specified acceptance ranges. The integrated magnetic stirring of the XTR-44 further enhanced homogeneity, particularly in difficult matrices.
Beyond analytical quality, capacity and workflow improvements represent a major advantage. The XTR-44 rotor accommodates 44 disposable polypropylene vials per run, providing laboratories with the flexibility to manage rush samples and large sample loads without bottlenecks. Combined with Milestone’s SFS-24 filtration system and standard post-extraction cleanup protocols (centrifugation, nitrogen evaporation, SPE), the platform supports a fully optimized, contamination-controlled workflow for EPA 1633A.
By reducing manual steps and ensuring reproducible heating conditions, Milestone’s ETHOS X gives laboratories a reliable tool to improve turnaround time prediction, enhance data confidence, and operate more sustainably. These results highlight the system’s value for commercial and regulatory testing labs that must balance cost control with strict quality expectations.
Key benefits observed:
- Up to 70% faster extraction (15 minutes vs hours).
- Higher throughput with 44-position rotor.
- Excellent data comparability and precision for all EPA 1633A analytes.
- Lower risk of contamination and analyte loss due to fewer handling steps.
- Easier workflow implementation and reduced operator-dependent variability.
As PFAS regulation continues to expand, laboratories need robust, scalable tools to meet demand. The ETHOS X with XTR-44 offers a validated and efficient pathway for improving PFAS sample preparation in solid matrices - helping labs “do more with less” while maintaining full compliance with EPA 1633A.