ComPass

WP1 forms the metrological backbone of the project, developing harmonised calibration protocols for passive samplers targeting CECs and trace metal(loid)s. Standardised procedures will cover determination of D_eff, R_s, elution efficiencies (f_e), and diffusive boundary layer thickness (δ) under controlled temperature, pH, salinity, and flow conditions at the Marine Biology Station Piran. Species-specific calibrations will be developed for selected Hg species (Hg⁰, DMHg, MeHgCl, [HgCl₄]²⁻) and organotin compounds (MBT, DBT, TBT), addressing uncertainties arising from species-dependent diffusion behaviour. All parameters and their uncertainties will be compiled into a comprehensive, openly accessible database with practical guidelines for reporting across all stages of passive sampler deployment.

WP2 integrates passive sampling with high-resolution mass spectrometry for comprehensive contaminant profiling. Resin-specific extraction conditions will be optimised and the NTS/SS screening workflow implemented on a UHPLC–Orbitrap Exploris 240, with the Galaxy open-source platform used for data processing in alignment with NORMAN Network initiatives. A dedicated LC-MS/MS method will be validated for direct quantitative CEC determination in seawater. For inorganic analytes, GC-ICP-MS (organotin), CV-AFS (mercury species), and ICP-QQQ-MS (trace metals) will be optimised, with full uncertainty budgets established for each analytical step.

WP3 synthesises and evaluates graphitic carbon nitride (GCN) nanosheets as innovative DGT binding phases. GCN is non-toxic, metal-free, inexpensive, and produced via a greener dry thermal route — calcination at 550°C followed by ball milling and thermal oxidation. Comprehensive characterisation will include SEM, AFM, TEM, XPS, and Raman spectroscopy, alongside a life cycle assessment (LCA). Classical and mixed resin combinations will also be tested against a broad range of NTS/SS targets and metals, with the best-performing materials selected for field deployment in WP4.

WP4 conducts two phases of in situ deployment at the Gulf of Trieste buoy Vida. Phase 1 uses classic passive samplers (DGT, POCIS, Chemcatcher®) for NTS/SS screening, generating an annotated compound list classified by the Schymanski system. Phase 2 introduces novel and mixed resins from WP3 for direct comparison. A prioritisation framework ranks CECs by abundance, toxicity, persistence, and bioaccumulation potential. Active seawater sampling from a research vessel provides reference concentrations for metrological TWA validation.

WP5 disseminates results through open-access publications in high-impact journals (ES&T, Marine Pollution Bulletin, Marine Chemistry) and conference contributions at ICMGP, EGU, Goldschmidt, and SETAC. The project engages NORMAN Network, EURAMET, ICES, and ARSO to connect findings to regulatory frameworks. A pilot study in the Bay of Kaštela will validate methodologies in a distinct environment. Public engagement includes citizen science initiatives, GIS-based contaminant visualisation platforms, open days at JSI and MBP-NIB, and social media outreach.