# Evaluation of targeted and high-resolution mass spectrometry methods for environmental monitoring of pharmaceuticals

## TL;DR

This study compares three mass spectrometry methods for detecting pharmaceuticals in water, finding that targeted MS/MS is best for routine monitoring while HRFS and DIA offer broader screening.

## Contribution

The study provides a direct comparison of MS/MS, HRFS, and DIA for pharmaceutical monitoring in water, highlighting their strengths and limitations in real-world conditions.

## Key findings

- MS/MS achieved the lowest LOQs (0.54 ng/L) and highest trueness (101%) for pharmaceutical quantification.
- HRFS and DIA showed broader screening capabilities but higher variability and LOQs compared to MS/MS.
- Matrix effects were compound- and matrix-specific, limiting the predictability of trueness.

## Abstract

This study presents a comparison of three mass spectrometry-based analytical approaches—targeted tandem mass spectrometry (MS/MS), high-resolution full scan (HRFS), and data-independent acquisition (DIA)—for the quantification and screening of 74 pharmaceuticals across four environmental water matrices: tap water, river water, and influent and effluent wastewater. The methods were validated in terms of limits of quantification (LOQ), trueness, precision, and matrix effects. MS/MS exhibited the best overall performance, achieving the lowest LOQs (median 0.54 ng/L), highest trueness (median 101 %), and minimal matrix effects, confirming its suitability for routine regulatory monitoring. HRFS and DIA, while showing higher LOQs and variability, provided broader screening capabilities with acceptable trueness for 63 % and 81 % of compounds, respectively, and enabled retrospective data analysis. The methods were applied to real samples from the Živný Stream in the Czech Republic to determine pharmaceutical contamination downstream of a wastewater treatment plant (WWTP).

-A method comparison was performed using MS/MS, HRFS, and DIA for 74 pharmaceuticals.-Matrix effects were compound- and matrix-specific, with limited predictive power for trueness.-The study supports a complementary role of targeted and full-scan MS in environmental monitoring.

-A method comparison was performed using MS/MS, HRFS, and DIA for 74 pharmaceuticals.

-Matrix effects were compound- and matrix-specific, with limited predictive power for trueness.

-The study supports a complementary role of targeted and full-scan MS in environmental monitoring.

Image, graphical abstract