Occurrence, Distribution and Ecological Risk of Organic UV Filters In a Freshwater Ecosystem: Insights into Potential Impacts of Sediment Dredging

Molnar, E. and Molnar, L. and Toth, G. L. and Fodor, I. and Svigruha, R. and Szanto, A. and Pirger, Zs. and Nemeth, Z. (2026) Occurrence, Distribution and Ecological Risk of Organic UV Filters In a Freshwater Ecosystem: Insights into Potential Impacts of Sediment Dredging. In: 16th International Conference on Environmental Pollution and Remediation, 2026.08.20-22., London.

Text ICEPR_137.pdf - Published Version Download (63kB)

Abstract

Shallow freshwater recreational lakes are increasingly recognized as potential hotspots of organic UV filters (OUVFs) originating from sunscreen products. Due to their hydrophobic properties, these compounds can accumulate not only in the water phase but also in sediments and biological matrices, resulting in multi-compartment exposure and potential ecological risks. Lake Balaton (Central Europe), the largest shallow freshwater lake in the region and a water body exposed to significant recreational pressure, provides an ideal model system to investigate these processes. Large-scale sediment dredging is planned in the lake; however, the management and reuse of dredged sediments remain unresolved, raising concerns about the potential remobilization and secondary spread of sediment-bound contaminants. In this study, the occurrence and distribution of five OUVFs (avobenzone [AVO], octocrylene [OC], octinoxate [EHMC], iscotrizinol [DBT], and ethylhexyl triazone [EHT]) were investigated across multiple environmental matrices (surface water, sediment, periphyton, and bivalve tissue) based on at least two sampling campaigns. Using SPE–UHPLC–MS/MS, all target compounds were detected in the investigated environmental compartments [1,2]. Distinct distribution patterns were observed among the investigated OUVFs, with surface water, periphyton, and biota exhibiting pronounced seasonal variability, whereas sediments acted as long-term reservoirs, particularly for EHT. Risk quotient (RQ)-based environmental risk assessment of the measured surface-water concentrations indicated high ecological risk (RQ > 1) for four compounds (AVO, OC, EHMC, and EHT), while DBT posed a medium risk [2]. These results provide baseline data prior to sediment dredging and demonstrate that sediments can act not only as sinks but also as potential secondary sources of contaminants upon disturbance. With the increasing application of dredged sediment reuse (e.g., as construction materials, soil amendments, or in biological treatment processes such as composting), the mobility and bioavailability of sediment-bound OUVFs remain insufficiently understood. This raises concerns regarding secondary exposure pathways, including plant uptake and leaching towards groundwater. These findings demonstrate that dredged sediments from recreational lakes may represent a previously overlooked pathway for the environmental redistribution of sunscreen-derived contaminants and should therefore be considered in future sediment management and reuse strategies.

Actions (login required)

View Item