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(77-09) Computer model (MAM-PEC) to predict environmental concentrations of antifoulants in harbours and estuaries. van Hattum, Bert*,1, Baart, Arthur2, 1 Institute for Environmental Studies, Amsterdam, Netherlands2 Delft Hydraulics, Delft, Netherlands ABSTRACT- Antifouling paints are believed to be essential for the streamlining of ship hulls, but its use may have a severe impact on non-target aquatic organisms, as in the case of tributyltin. New antifouling agents are expected to replace TBT-based products in the near future. For the exposure assessment in marine environments there is a need for reliable chemical fate models. Existing models were tested and their performance and shortcomings evaluated; this experience was then used to develop a new user-friendly and generic chemical-fate computer model (MAM-PEC) specifically for antifouling agents. The study was commissioned by the Antifouling Working Group of the European Paint Makers Association (CEPE / CEFIC) and sponsored by the European Commission (DG XI). The model predicts concentrations of antifoulants in five generalised 'typical' marine environments (open sea, shipping lane, estuary, commercial harbour, yachting marina). The user can specify: emission factors (e.g., leaching rates, shipping intensities, residence times, ship hull underwater surface areas), compound-related properties and processes (e.g., Kd, Kow, Koc, volatilisation, speciation, hydrolysis, photolysis, biodegradation), and properties and hydrodynamics related to the specific environment (e.g. currents, tides, salinity, DOC, suspended matter load, port dimensions).For TBT, Irgarol and other compounds model-predictions were compared with measured values from cases studies and literature derived data to confirm the validity of the model. Key words: antifoulants, model, exposure-assessment, chemical-fate |
