Can micropollutants act as mutagens? A case study of surface runoff, riverine water and sediments in Poland, central Europe

Water contamination is a longstanding global issue with micropollutants (MPs) posing risks to ecosystems and human health. This study aimed to: (i) identify 10 benzotriazoles (BTRs) and 10 bisphenols (BPs) in a mid-sized agricultural catchment, (ii) estimate daily loads of hazardous MPs and assess their environmental risks (iii) evaluate the mutagenicity of surface runoff (SR), riverine water (RW), supernatant from bottom sediment (SBS) and suspended sediments (SS) from the Wełna River catchment (Oder River basin, Poland). Samples were collected in October 2022 and January 2023. BTRs and BPs were analysed using USAEME and GC-MS, mutagenicity was assessed via microplate Ames MPF test. 5Cl-BTR was detected in all samples, BPA appeared in 71.4%, the highest concentrations were 16,393 ng/L for 5Cl-BTR and 99,998 ng/L for BPAP. The Ames test confirmed mutagenicity in all collected sampleswith higher levels in autumn than in winter. Environmental risk assessment classified most BTRs as low-risk, except 1H-BTR, 5Cl-BTR and UV-P (medium) while BPs posed low to high risks. Findings confirm the presence of MPs in aquatic environments and their potential mutagenic effects although other pollutants may also contribute. • 10 BTRs and 10 BPs were identified and tested for mutagenicity • BTRs and BPs were analyzed by USAEME/GC-MS, and mutagenicity by Ames MPF assay • 5Cl-BTR and BPA were the most commonly found micropollutants • 5Cl-BTR and BPAP exhibited the highest concentrations in investigated compound groups • All samples from agriculture catchment exhibited mutagenic properties according to the Ames test