PT03 Persistent Organic Pollutants (POPs)
Exhibit Hall
8:00 AM - Tuesday
(PT025) Behaviour of Irgarol 1051 and PAHs in sediment/water systems.
Zhou, J L1, King, A J1, Gatidou, G1, 1 University of Sussex, Brighton, East Sussex, UK
ABSTRACT- The distribution of organic contaminants between particles and water is fundamental in the control of their movement and impact in the aquatic environment. In this study sediment and water samples were regularly collected from Brighton marina and Shoreham Harbour, UK, to determine the concentrations of an antifouling booster biocide Irgarol 1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine), M1 (2-methylthio-4-tert-butylamino-s-triazine) which is the principal degradation product of Irgarol 1051, and 16 polycyclic aromatic hydrocarbons (PAHs). Aqueous concentrations of Irgarol 1051 ranged from <1 to 960 ng/l with highest mean concentrations generally associated with berths for larger vessels and with the main channels. The total concentrations of 16 parent PAHs varied from <1 to 11377 ng/l. Temporally, highest concentrations of both Irgarol 1051 and PAHs were recorded in the winter months. Elevated levels of Irgarol 1051 were also encountered at the beginning of the season, coinciding with the introduction of newly antifouled vessels. Increased concentrations of Irgarol 1051 and PAHs also followed dredging in the marina, through their desorption from sediments. Field derived distribution coefficients for individual PAHs tend to exceed those predicted from equilibrium partition models. The results show clearly that PAH behaviour in marine systems is complex, and controlled by the interplay of PAH sources, physicochemical properties, water and sediment movement, and field conditions. The extended partition model incorporating soot carbon has achieved limited success in predicting PAH behaviour.
Key words: Irgarol 1051, Antifouling booster biocide, PAHs, Sediment