Advanced LC/MS/MS Methods for CECs in Waters

Drinking Water
Oral Presentation

Prepared by Y. Li
Eurofins Eaton Analytical, LLC, 110 South Hill Street, South Bend, Indiana, 46617, United States

Contact Information: [email protected]; 574-472-5562


Water scarcity is an increasing problem due to growing global demand for water and climate change. Growing population and urbanization, along with expansion of irrigated agriculture and industry, is increasing water demand for water. Climate change is altering weather and precipitation patterns around the world, causing more shortages and droughts in some areas and floods in others. Increasing water contamination is also causing insufficient water supply. As a result, the use of highly treated municipal wastewater as a drinking water source is increasingly important. Wastewater reclamation for indirect potable reuse (IPR) or direct potable reuse (OPR) has become a viable option to meet increasing municipal drinking water supply requirements in certain geographical locations. Monitoring emerging contaminants or contaminants of emerging concern (CECs) has played a critical role in reclaimed waters for potable reuse.

Current analytical methods used for CECs primarily include LC/MS/MS combined with solid-phase extraction (e.g., EPA 1694), GC/MS or HRMS combined with derivatization following either solid-phase extraction or liquid-liquid extraction (e.g., EPA 1698), and various laboratory proprietary methods. All these methods involve sample extraction, concentration enrichment, and/or derivatization. These procedures are typically time-consuming, labor-intensive, and often only suitable for certain CECs with desirable recoveries. Therefore, multiple methods are often required to monitor a selected list of CECs of interest. In addition, reclaimed wastewaters often present significant matrix interferences to extraction/derivatization recoveries and other impacts on quality controls.

This work will describe two new direct injection LC/MS/MS methods in positive and negative electrospray ionization (ESI) modes for a wide range of commonly monitored CECs in potable reuse. Over 80 CECs include pharmaceuticals and personal care products (PPCPs), steroids and hormones, phenolic endocrine disrupting chemicals (EDCs), flame retardants, and household cleaning products. This presentation will demonstrate the method capability (accuracy, precision, and sensitivity) and applicability of monitoring CECs at different treatment stages from finished drinking water, drinking water treatment, environmental and engineered buffers, to WWTP effluents. These new direct injection LC/MS/MS methods with isotope dilution/internal standard analysis can provide a few advantages over the current methods. The advantages may include applicability of analyzing more CECs, quicker availability of laboratory results, better data accuracy, and lower analytical costs. In addition, the advanced LC/MS/MS techniques are also able to provide sufficient sensitivity and specificity.

Presentation Description:
This presentation will introduce two new direct injection LC/MS/MS methods for analysis of over 80 commonly-monitored CECs in drinking water, source water supplies, and WWTP effluents for potable reuse. These methods provide a few advantages over existing methods.