Regulated Drinking Water Testing: PFAS Detection, Sample Prep & Real Lab Insights

🎤Alex Brody

In this episode of Concentrating on Chromatography, we sit down with Alex Brody, an organic chemist at Aqua America, to discuss the rigorous analytical methods required for regulated drinking water testing.

Alex walks us through the multi-step PFAS detection process using EPA Method 537.1, including extraction, nitrogen blowdown concentration, and LC-MS analysis. He explains why sample preparation and quality control are critical for achieving trace-level detection—and why these methods can't be rushed or simplified, even with new technologies available.

We also explore taste and odor investigations, disinfection byproducts, and volatile organic compounds, plus the surprising reality of why regulated labs move slowly when adopting new instrumentation. You'll learn about the quality control checkpoints, peer review processes, and the misconceptions surrounding analytical turnaround times in compliance labs.

Topics Covered:

• Role of organic chemistry in regulated drinking water labs
• EPA compliance requirements and regulatory bodies (EPA, PA-DEP)
• PFAS detection using Method 537.1 and LC-MS
• The critical importance of nitrogen blowdown sample concentration
• Taste and odor analysis: MIB, Geosmin, and unknown compound identification
• Why regulated methods evolve slowly (validation timelines, approval processes)
• Quality control procedures: calibration checks, matrix spikes, surrogate standards, internal standards
• Automated sample preparation and lab efficiency
• Future PFAS regulations and Method 533 expansion

Ideal For:

• Analytical chemists and environmental lab professionals
• Water utilities and compliance officers
• Chromatography practitioners interested in regulated workflows
• Anyone curious about how drinking water safety is ensured

Video Transcription

Ensuring Safe Drinking Water Through Advanced Analytical Chemistry

Insights from a Regulated Water Testing Laboratory

Analytical laboratories responsible for regulated drinking water testing operate under strict compliance frameworks to ensure the delivery of safe and reliable water supplies. In this interview, Alex, an organic chemist at Aqua America, outlines the scope of analytical work conducted in a modern water quality laboratory. The team primarily focuses on the determination of taste- and odor-causing compounds, disinfection byproducts, volatile organic compounds (VOCs), and per- and polyfluoroalkyl substances (PFAS). These analyses rely heavily on GC-MS and LC-MS instrumentation, supported by rigorous maintenance programs to ensure continuous operational performance and data reliability.

Regulatory Compliance and Quality Control in Drinking Water Analysis

Operating as a regulated drinking water laboratory requires adherence to stringent requirements established by agencies such as the U.S. Environmental Protection Agency (EPA) and state-level regulatory bodies. Compliance is driven by extensive quality control protocols integrated into every analytical batch. Typical workflows include calibration verification, matrix spike recovery assessments, internal standard monitoring, and surrogate performance checks. Notably, analytical batches are often limited in sample number to accommodate a substantial proportion of quality control samples, reflecting the critical importance of data defensibility in regulatory reporting.

One common misconception is the perceived speed at which results can be delivered. In reality, comprehensive sample preparation, including extraction procedures and validation steps, can extend turnaround times to a full working day or longer. Additionally, validated regulatory workflows impose limitations on the rapid adoption of new analytical technologies, as method modifications must undergo formal evaluation and approval before implementation.

Analytical Strategies for Taste and Odor Investigations

Taste and odor events represent a significant operational challenge for water utilities. Standard targeted methods are routinely applied for compounds such as 2-methylisoborneol (MIB) and geosmin, which are commonly associated with earthy or musty sensory characteristics. When targeted analysis does not reveal the source, laboratories employ broad-scan GC-MS screening combined with spectral library interpretation to identify potential causative compounds. In some cases, sensory evaluation panels complement instrumental analysis, providing preliminary insight into potential treatment-related or environmental influences affecting water quality.

PFAS Monitoring: Methodological Complexity and Trace-Level Sensitivity

PFAS determination represents a rapidly evolving priority in drinking water monitoring. The laboratory currently applies EPA Method 537.1, with efforts underway to expand capabilities through certification for Method 533, thereby broadening analyte coverage. Analytical workflows typically involve solid-phase extraction followed by solvent evaporation using nitrogen-assisted blow-down techniques to achieve the trace-level sensitivity required for regulatory compliance. This concentration step is essential because PFAS compounds remain non-volatile under controlled evaporation conditions, enabling enhanced detection performance upon reconstitution and LC-MS analysis.

Future Directions in Drinking Water Analytics

Looking ahead, the primary technological driver in regulated water analysis is the demand for increasingly lower detection limits and expanded compound coverage. While regulatory frameworks can slow methodological innovation, laboratories continue to pursue efficiency improvements, such as automated sample preparation systems and optimized analytical workflows. These advances support the growing need to process high sample volumes while maintaining the stringent data quality standards required for public health protection.

Ultimately, the work performed in regulated drinking water laboratories represents a critical intersection of analytical chemistry, environmental monitoring, and public safety. Continuous methodological refinement, coupled with advances in mass spectrometry and sample preparation technologies, will play a central role in addressing emerging contaminants and ensuring long-term water quality assurance.

This text has been automatically transcribed from a video presentation using AI technology. It may contain inaccuracies and is not guaranteed to be 100% correct.

Concentrating on Chromatography Podcast

Dive into the frontiers of chromatography, mass spectrometry, and sample preparation with host David Oliva. Each episode features candid conversations with leading researchers, industry innovators, and passionate scientists who are shaping the future of analytical chemistry. From decoding PFAS detection challenges to exploring the latest in AI-assisted liquid chromatography, this show uncovers practical workflows, sustainability breakthroughs, and the real-world impact of separation science. Whether you’re a chromatographer, lab professional, or researcher you'll discover inspiring content!

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