# Assessment of dynamics and variability of organic substances in river bank filtration for prioritisation in analytical workflows

## TL;DR

This study assesses organic pollutants in river bank filtration to prioritize them for water safety.

## Contribution

A new prioritization scheme for organic micropollutants using non-targeted analysis and sampling data is introduced.

## Key findings

- Quasi-omnipresent substances account for 44% of cumulative detections despite being only 7% of compounds.
- Moderately common substances make up 50% of cumulative detections from 31% of compounds.
- NTA and suspect screening show similar results, validating NTA's effectiveness.

## Abstract

Bank filtration supports the growing global demand for drinking water amidst concerns over organic micropollutants (OMPs). Efforts to investigate, regulate and manage OMPs have intensified due to their documented impacts on ecosystems and human health. Non-targeted analysis (NTA) is critical for addressing the challenge of numerous OMPs. While identification in NTA typically prioritises compounds based on properties like toxicity, considering substance quantity, occurrence frequency and exposure duration is essential for comprehensive risk management. A prioritisation scheme, drawing from intensive sampling and NTA of bank filtrate, is presented and reveals significant variability in OMP occurrence. Quasi-omnipresent substances, though only 7% of compounds, accounted for 44% of cumulative detections. Moderately common substances, constituting 31% of compounds, accounted for 50% of cumulative detections. Rare compounds, comprising 61%, contributed only 6% to cumulative detections. The application of suspect screening for 31 substances to the dataset yielded results akin to NTA, underscoring NTA’s value. Correlation between both methods demonstrates the efficacy of high-resolution mass spectrometry-based NTA in assessing temporal and quantitative OMP dynamics.

The online version contains supplementary material available at 10.1007/s11356-024-34783-9.