OCCURRENCE OF POLYBROMINATED DIPHENYLETHERS, POLYCHLORINATED DIBENZO-P-DIOXINS, DIBENZOFURANS AND BIPHENYLS IN COASTAL SEDIMENTS (NW ADRIATIC SEA, ITALY) INTRODUCTION AND OBJECTIVES Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) are ubiquitous and persistent contaminants in the marine environment [1], [2]. PCDDs and PCDFs (PCDD/Fs) and PCBs are released from various sources, such as incinerators, chemical industries, and municipal wastewater effluents. The contamination in the marine environment also includes a variety of brominated flame retardants [3]. This group of emerging pollutants includes polybrominated diphenyl ethers (PBDEs), which are used in a variety of commercial applications (plastics, textiles, electronic circuitry and other materials) to prevent fires. Due to their hydrophobic properties, these compounds tend to strongly partition to particulate matter in the marine environment and settle through the water column to the sediments, which act as their final sink. In this study, sediment samples were analyzed to determine levels and spatial trends of contaminants associated with historical industrial activities in the area (PCDDs/PCDFs, dl-PCBs), compared to more modern industrial chemicals (PBDEs). Samples were collected from Pialassa Baiona, an eutrophic coastal lagoon located along the northern Adriatic coast of Italy. Although the area is a wetland of international importance (RAMSAR Convention, EU Wild Birds Directive, EU Habitats and Species Directive), significant agricultural, urban and industrial activities have released toxic chemical pollutants into the lagoon. EXPERIMENTAL Four sampling areas were selected combining the distance from industrial inputs (near and far) and the distance from the sea (near and far) (Figure 1). Two areas were located near to the anthropogenic disturbance (i.e. industrial area), along the southern edge of the lagoon (areas 1 and 2), and two areas were located northward, far from the impacted area (areas 3 and 4), on the other hand, area 2 and 3 were near the seaward channels confluence, and area 1 and 4 were landward. Three sites (labelled A, B and C) were randomly selected for each area and sediment replicate samples (top 5 cm) were collected at each site by means of a Wildco® box corer. A total of 36 sediment samples were collected and Soxhlet extracted with toluene. Extract clean-up was executed on a multi-layer silica gel column.and activated alumina. Two fractions were collected: one containing PCDD/Fs and one for PCBs and PBDEs. The instrumental analyses of PCDD/Fs, PCBs and PBDEs were conducted using high-resolution gas chromatography (6890N GC, Agilent, USA) and mass spectrometry (JMS-700D, JEOL, Japan). The instrumental conditions for the analyses of PCDD/Fs and PCBs were as detailed in Ok et al. [4]. FINAL REMARKS PCDD/Fs, PCBs and PBDEs levels found in sediments from the southern area of the lagoon reflected those found in estuarine and coastal areas impacted by urban and industrial sources. Conversely, sediments from the northern-.central area reported concentrations similar to background concentrations of European coastal areas. The dominance of BDE-209 in the PBDE distribution of sediments reflects that the deca-product was probably the one largely used in the area of study. Although deca-DBDE was banned in Europe in 2008, there is still a concern that it may debrominate in the wider environment to form less-brominated BDE congeners, which are more bioavailable than BDE-209 itself to the aquatic biota. Roberta Guerra 1 , Gon Ok 2 , Seok-hyung Lee 2 , No-jin Park 2 1 Centro Interdipartimentale di Ricerca per le Scienze Ambientali (C.I.R.S.A.), University of Bologna, Italy 2 Department of Environment Atmospheric Science, and Dioxin Research Center, Pukyong National University, Busan, Korea RESULTS AND DISCUSSION There was a broad range of ΣPCDD/F and dioxin-like PCBs (dl-PCB) concentrations in bulk sediments from Pialassa Baiona lagoon (0.55 - 39.4 and 0.02 to 15.32 pg WHO-TEQ/g, respectively). The ΣPCB (tetra-CBs to deca-CBs) and ΣPBDE (sum of 38 congeners) levels were in the range of 8.97-634 ng/g and 1.62-40.6 ng/g, respectively, with the highest concentrations found near the industrial area (area 1). The spatial distribution of PCBs and PBDEs in Pialassa Baiona indicated that the southern part of the lagoon was more contaminated than the northern-central part (areas 2,3,4). Mercury, polycyclic aromatic hydrocarbons (PAHs) and PCBs have historically been elevated in the Pialassa Baiona (Fabbri et al, 1998; Matteucci et al., 2001; Fabbri et al., 2003). Urban and industrial sources have released these contaminants into the lagoon for decades, resulting in high levels of sediment concentrations in the proximity of the industrial area in comparison to the northern-central lagoon (Trombini et al, 2003; Guerra, 2012). Sediment concentrations PBDE congeners patterns The median ΣPBDE (4.70 ng/g) and BDE-209 (3.84 ng/g) concentrations found in this study are similar to results from other European countries [10]. Except area 1, the level of ΣPBDE contamination (excluding BDE-209) was less than 1 ng/g, which is similar to the levels reported in sediments collected from estuarine and coastal areas in North Sea, the western Scheldt Estuary and the coastal areas of Catalonia [10]. The predominant BDE congener was BDE-209 accounting for ∼90% of total PBDE, followed by ∼10% octa- and nona-BDEs. BDE-209 is the primary component of the deca-BDE commercial mixture used in textiles and plastics [11]. Although the deca-BDE is now banned in electrical goods sold in Europe, it is unlikely that sedimentary concentrations will rapidly decline given the widespread usage in industrial and consumer products. Figure 1. Map of Pialassa Baiona lagoon showing sampling sites References [ ] A. Gómez-Gutiérrez, E. Garnacho, J. M. Bayona, J. Albaigés: “Assessment of the Mediterranean sediments contamination by persistent organic pollutants”. Environ Pollut, 148, 396-408, 2007. [2] E. Eljarrat, A. De La Cal, D. Larrazabal, B. Fabrellas, A. Rodriguez Fernandez-Alba, F. Borrull, R. M. Marced, D. Barcelo: “Occurrence of polybrominated diphenylethers, polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls in coastal sediments from Spain”. Environ Pollut, 136, 493-501, 2005. [3] R. J. Law, C. R. Allchin, J. de Boer, A. Covaci, D. Herzke, P. Lepom, S. Morris, J. Tronczynski, C. A. de Wit: “Levels and trends of brominated flame retardants in the European environment”. Chemosphere, 64, 187-208, 2006. [4] G. Ok, S. H. Lee, S. M. Hwang, N. J. Park: “Historical trends and analysis of PCDD/DFs, PCBs and Emerging POPs in sediment core in Yeong-il bay, Korea”. Proceedings of Japan Society of Analytical Chemistry and Japan Analytical Instruments Manufactures Association Conference, Tokyo, June 9–11, 2009, 371. [5] D. Fabbri, O. Felisatti, M. Lombardo, C. Trombini, I. Vassura: “The Lagoon of Ravenna Italy. : Characterisation of mercury-contaminated sediments”. Sci Total Environ, 213, 121- 128, 1998. [6] G. Matteucci, P. Rossini, A. Arcangeli, G. De Falco, P. Fonti, S. Guerzoni: “Organic pollution in a ramsar site (Piallassa Baiona, northern Adriatic Sea)”. Ann Chim-Rome, 91, 1-12, 2001. [7] D. Fabbri, I. Vassura, C.-G. Sun, C. E. Snape, C. McRae, A. E. Fallick: “Source apportionment of polycyclic aromatic hydrocarbons in a coastal lagoon by molecular and isotopic characterization”. Mar Chem, 84, 123-135, 2003. [8] C. Trombini, D. Fabbri, M. Lombardo, I Vassura, E. Zavoli, M. Horvat: “Mercury and methylmercury contamination in surficial sediments and clams of a coastal lagoon (Pialassa Baiona Ravenna Italy)”. Cont Shelf Res, 23, 1821-1831, 2003. [9] R. Guerra: “Polycyclic Aromatic Hydrocarbons, Polychlorinated Biphenyls and Trace Metals in Sediments from a Coastal Lagoon (Northern Adriatic, Italy)”.Water Air Soil Pollut, 223, 85-98, 2012. [10] R.J. Law, C.R. Allchin, J. de Boer, A. Covaci, D. Herzke, P. Lepom, S. Morris, J. Tronczynski, C.A. de Wit: “Levels and trends of brominated flame retardants in the European environment”. Chemosphere 64, 187-208, 2006. [11] M.J. La Guardia, R. C. Hale, E. Harvey: “Detailed Polybrominated Diphenyl Ether (PBDE) Congener Composition of the Widely Used Penta-, Octa-, and Deca-PBDE Technical Flame-retardant Mixtures”. Environ Sci Technol 40, 6247-6254, 2006. Figure 2. Concentrations of PCBs, PCDD/Fs and PBDEs