BIVALVES ORGANIC POLLUTION ALONG EASTERN MEDITTERANEAN COASTS

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1 Proceedings of the 13 th International Conference on Environmental Science and Technology Athens, Greece, 5-7 September 2013 BIVALVES ORGANIC POLLUTION ALONG EASTERN MEDITTERANEAN COASTS K. M. KASIOTIS 1, A. PAPADI-PSYLLOU 3, C. EMMANOUIL 1, P. ANASTASIADOU 1, OYA OKAY 2 and K. MACHERA 1 1 Benaki Phytopathological Institute, Department of Pesticides Control and Phytopharmacy, Laboratory of Pesticides Toxicology, 8 St. Delta Street, Kifissia, Athens, Greece, 2 Istanbul Technical University Faculty of Naval Architecture and Ocean Engineering 34469, Maslak, Istanbul/Turkey 2 Department of Agriculture, Crop production and Rural Environment Analytical Chemistry and Pesticides, University of Thessaly, School of Agricultural Sciences Fytokou Street, Nea Ionia Magnisias, Greece k.machera@bpi.gr EXTENDED ABSTRACT Persistent chemicals and new emerging pollutants are continuously found in marine waters and biota. Out of these, polycyclic aromatic hydrocarbons (PAHs) are carcinogens or probable carcinogens and capable of long term harmful effects in vertebrates. They are common marine pollutants due to shipping activity and oil spill accidents. Also, organochlorine pesticides (OCs) constitute a family of persistent, lipid-soluble compounds that include industrial chemicals. The Mediterranean Sea is an ecosystem directly affected by a variety of anthropogenic activities including industry, municipal, touristic, commercial and agricultural activities. The Mediterranean mussel is Mytilus galloprovincialis, which is wide distribution and has common use as sea food. These marine organisms are filter feeders and were selected because they have only a limited ability to metabolize organic pollutants especially PAHs and are therefore often used to monitor PAHs contamination in the marine environment. The presented work was implemented in the frames of a bilateral funded project (GSRT) between Greece and Turkey entitled Pollution monitoring of the Northern Aegean coast by use of transplanted mussels: determination of priority pollutants and their levels and development of suitable biomarkers. In this regard a gas chromatographic tandem mass spectrometric method (GC-MS/MS) was developed and validated to monitor 34 compounds (16 EPA priority PAHs and 18 OCs) whose sample preparation steps were based on previously described QuEChERS procedure. Analyses of Turkish samples of 2011 have shown the occurrence of 7 pollutants (5 PAHs, 2 OCs) in a total of 11 samples. Hence pollutants with high bioconcentration potential were detected in mussels samples a fact which has to be considered for risk assessment purposes. Monitoring and analyses of first batch of Greek samples and second batch of Turkish samples are currently underway. Keywords: Bivalves, Mytillus galloprovinciallis, GC-MS/MS, PAHs, OCs, emerging pollutants, monitoring, Mediterranean Sea 1. INTRODUCTION Environmental contaminants are constantly found in marine waters and biota. Out of these, polycyclic aromatic hydrocarbons (PAHs) are carcinogens or probable carcinogens and capable of long term harmful effects in vertebrates. They are common marine pollutants due to shipping activity and oil spill accidents. Also, organochlorine pesticides (OCs) constitute a family of persistent, lipid-soluble compounds that include industrial chemicals. They are banned and cause a variety of neurotoxic, hormonal- and immunomodulating and tumorigenic effects and are extremely persistent in the environment

2 including marine waters. In humans, the diet is the main source of intake. Contaminated fish and shellfish fats are the main contributors to PAHs and OCs intake in humans, because as lipophilic compounds they can easily cross lipid membranes and have the potential to bioaccumulate in aquatic organisms. The Mediterranean Sea is an ecosystem directly affected by a variety of anthropogenic activities including industry, municipal, touristic, commercial and agricultural activities. The Mediterranean mussel is Mytilus galloprovincialis, which is widely distributed and has common use as sea food. These marine organisms are filter feeders and selected in our work because they have only a limited ability to metabolize organic pollutants, especially PAHs, and are therefore often used to monitor PAHs and OCs contamination in the marine environment. 2. MATERIALS AND METHODS 2.1 Experimental Part Mussels (Mytilus galloprovinciallis) were transplanted at the selected geographical points in Greece and Turkey and collected after specific time intervals. In Greece mussels were placed at Volos (Magnisia Prefecture), Salamina and Megara (Attiki Prefecture). In Turkey samples were transplanted at Ibrice Bay, Guneyli Bay, Kilye Bay and Kabatepe Bay. The GC-MS/MS analysis was performed on a Chromtech Evolution MS/MS triple quadrupole mass spectrometer built on an Agilent 5975 B inert XL EI/CI MSD system. Samples were injected with a Gerstel MPS-2 autosampler using a 10 μl syringe. Two transitions were selected for the monitoring of each of the 34 compounds. Collision energies varied from 3 to 20 ev. Separations were performed on an HP-5MS Ultra inert 30m 0.25mm 0.25 μm column (J&W Folsom, USA). Helium was used as the carrier gas at a flow rate of 1.5 ml/min. The column oven temperature program initiated at 70 C for 4 min, then increased to 150 C with a rate of 25 C/min, then to 225 C with a rate of 3 C/min, and finally to 310 C with a rate of 10 C/min, remaining there for 1.8 min. The total GC analysis time was 42.5 min. The QqQ mass spectrometer was operated in EI-MS/MS mode in Multiple Reaction Monitoring (MRM) data acquisition mode (see Table 1 for transitions and collision energies). The transfer line, manifold and source of ionization temperatures were 300, 40 and 230 C. For the MS/MS experiments Argon % was used as a collision gas and the collision cell pressure was set at 1.7mTorr. The electron multiplier voltage was set at 2000 V. 2.2 Sample Preparation- Extraction Sample Preparation-Extraction was based on the QuEChERS procedure (Anastassiades et al. 2003) that was performed on freeze-dried mussels tissue. Briefly, samples were extracted initially with acetonitrile (containing 1% acetic acid) after homogenization and agitation by vortex. Into this mixture QuEChERS AOAC salts mix ( ) were added, the mixture was shaken by hand for 1 min, centrifuged and the organic layer was stored with sodium sulphate overnight at -20 C (see Agilent application). Then evaporation, purification by passage through activated silica (two times) and elution with dichloromethane-hexane afforded the target compounds, whose mixture was evaporated and adjusted to a final volume of 1mL. Then 1μL of the latter was injected to the GC- MS/MS system.

3 2.3 Validation of the analytical procedure An analytical method was developed for the analysis of 34 substances which included 16 EPA priority PAHs and 18 OCs (see Table 1). Validation study was performed in terms of recovery, linearity, intra-day and inter-day precision. Matrix matched calibration curves were prepared by adding appropriate volumes of the standard working solution mix at blank mussels sample. Calibration curves ranged from 5 to 500 ng/g dry weight (dw) with 5 calibration points at 5, 20, 50, 100 and 500 ng/g dw. The selected range was decided considering two parameters a) the coverage of expected concentrations usually encountered for these compounds in Mytillus galloprovinciallis and b) the analytical performance of the method. The recovery and precision of extraction method were determined as the average of five spiked blank matrix at concentration levels of 5, 20 and 100 ng/g dw. Precision of chromatographic method (expressed by relative standard deviation, RSD %) was derived after five repeated injections of spiked samples at 5 and 20 ng/g dw. Precision is expressed as RSD % of the intra-day and inter-day analyses (n=5) over 1 and 5 days respectively. Analytical limit of detection (LOD) calculation was based on parameters from the calibration curve (statistical definition 3.3 (S Y/ x)/α, S Y/ x represents the residual standard deviation and α is the slope of the respective calibration plot). 3. RESULTS 3.1. Validation Regression analysis showed an excellent linear relationship with coefficient of determination (r 2 ) for all analytes > The analytical method exhibited good performance as recoveries ranged from 60 to 110%.The Limit of Detection (LOD) values ranged from 3 to 67 ng/g dw. As regards precision all analytes met the criterion of an RSD value < 20%, with the majority of them exhibiting values below 10% Contaminants Levels Seven compounds were detected (naphthalene, acenapthene, phenathrene, fluoranthene, pyrene, pp-dde and endrin) in 11 Turkish samples of 2011 which was the first batch of samples that have been analyzed. Concentrations in these samples varied from 10.3 to 42.9 ng/g dw as depicted (Table 2) the results of the analyses of the 11 samples sent by the Turkish side are presented. From total 34 compounds monitored, 7 were detected at the Limit of Detection (LOD) or above the LOD. The LOD values are depicted in Table 1 and are expressed in ng/g dw.

4 Table 1. Analytes MRM transitions (precursor to product ion) and collision energies PAHs/ Ocs Naphthalene Acenaphthylene Acenaphthene Fluorene α-bhc β-bhc δ-bhc Phenanthrene Anthracene γ-bhc Heptachlor Aldrin Heptachlor epoxide Fluoranthene Pyrene α-endosulfan Dieldrin pp-dde Endrin Ion Collision Energy PAHs/ Ocs Ion Collision Energy 128 => 102 q => => β-endosulfan 195 => 159 q => => => 150 q => 165 pp-ddd q => 153 q => => => 281 Endrin aldehyde => 165 q => 245 q => => 236 q -12 Endosulfan sulfate 387 => => => => 165 pp-ddt q => => => 101 Endrin ketone q => => => Benzo(a)anthrac 228 => 226 q => 176 q -14 ene 228 => => 176 q => 226 Chrysene => => => Methoxychlor 219 => => 169 q => Benzo(b)fluorant 252 => 250 q => 239 q -5 hene 250 => => 193 q -20 Benzo(k)fluorant 252 => 250 q => hene 250 => => => 250 Benzo(a)pyrene q => 253 q => => 200 q -20 Indeno(1,2,3-276 => 274 q => cd)pyrene 276 => => 200 q -14 Dibenzo(a,h)anth 278 => 276 q => racene 278 => => Benzo(g,h,i)peryl 276 => 274 q => ene 276 => => 206 q -6 q quantitation transition 263 => 193 q => => => 246 q => 191 q => 245-6

5 Table 2. LOD values and concentration range for contaminants detected in 2011 Turkish samples Compound LOD (ng/g dw) Concentration Range (ng/g dw) Napthalene Acenapthene 13.9 LOD Phenanthrene 10.2 LOD-10.3 Fluoranthene Pyrene pp-dde 10.8 LOD Endrin 18.7 LOD Figure 1. Total Ion Chromatogram of a standard solution at 500 ng/g dw of the 34 compounds (PAHs + OCs)

6 Abundance I o n ( t o ) : T U R K _ S a m p _ D \ d a t a. m s Time--> Abundance I o n ( t o ) : T U R K _ S a m p _ D \ d a t a. m s Time--> Figure 2. MRM transition ions for a positive Turkish sample with Pyrene residues (quantitation ion at m/z 200, confirmation ion at m/z 150) 4. CONCLUSIONS A sensitive GC-MS/MS method based on QuEChERS procedure was developed for the determination of PAHs and OCs in mussels samples form Greek and Turkish estuaries. Low but not negligible levels of 5 PAHs and 2 OCs were detected in the 11 Turkish samples originating from Hence pollutants with high bio-concentration potential were detected in mussels samples a fact which has to be considered for further risk assessment purposes. Monitoring and analyses are still continued in 2012 samples of both countries. The overall results, including those from Greek samples as well, will provide a more thorough view of the current status of PAHs and OCs potential burden in that part of Eastern Mediterranean. REFERENCES 1. Anastassiades M, Lehotay SJ, Stajnbaher D, Schenck FJ (2003) Fast and easy multiresidue method employing acetonitrile extraction/partitioning and dispersive solid-phase extraction for the determination of pesticide residues in produce, J Assoc. Off. Anal. Chem. Int. 86: Agilent Application,