CHEMICAL STUDY OF BEHAVIOUR AND TRANSPORTATION OF AL-FE-MN-CU-PB-ZN IN THE ESTUARY OF ACHELOOS

THIS STUDY CONCERNS THE CHEMICAL BEHAVIOUR AND TRANSPORTATION OF SOME TRACE METALS (AL,CU,FE,MN,ZN,PB) AMONG THE DISSOLVED, SUSPENDED AND SEDIMENT PHASE, IN AN ESTUARINE ENVIRONMENT. THE AREA STUDIED IS AN INTERESTING MEDITERRANEAN ESTUARY. A NETWORK OF SEVERAL SAMPLING STATIONS WAS DESIGNED FOR THE PURPOSES OF THIS STUDY. SAMPLES FROM THE DISSOLVED AND PARTICULATE PHASE WERE COLLECTED WITH NANSEN-10C BOTTLES. SEDIMENT SAMPLES WERE COLLECTED WITH A MACKERETH CORER. THE DISSOLVED METAL WAS PRECONCENTRATED WITH CHELEX-100 RESIN AND MEASURED WITH GFAAS. THE TRACE METAL CONTENT OF THE PARTICULATE MATTER AND THE SEDIMENTS WAS EXTRACTED EITHER BY USING COLD-DILUTED HCL OR BY USING HOT-CONC. HNO3, AND THEN MEASURED WITH AAS. IN ADDITION TO THE ABOVE, A SERIES OF PHYSICAL PARAMETERS WERE MEASURED IN SITU (PH, D.O., S%, T C). THE RESULTS WERE WORKED OUT BY USING APERSONAL COMPUTER IN ORDER TO FIND CORRELATIONS AMONG THE VARIOUS PARAMETERS' MEASURED AND DEFINE THE MECHANISMS PREVAILING IN THE ABOVE DISCUSSED SYSTEM. THE CONCLUSION OBTAINED IS THAT IN THE INTERMIXING ZONE OF FRESH AND SALINE WATERS A SERIES OF INTERESTING CHEMICAL PHENOMENA TAKE PLACE. ALL METALS EXAMINED, WITH THE EXCEPTION OF FE AND AL, PARTICIPATE IN THESE PHENOMENA SHOWING VARIOUS TRENDS WHICH IN SOME CASES ARE SEASONAL. THE MOST IMPORTANT OF THESE IS THE TRANSPORT OF PB AND ZN FROM THE DISSOLVED TO THE PARTICULATE PHASE, THE INCREASE OF DISSOLVED METALS IN SALINE OFFSHORE WATERS, THE INCREASE OF THE CONCENTRATIONOF MN AND ZN IN THE SEDIMENTS NEAR THE MOUTH AND THE ANALOGOUS DISTRIBUTIONS OF AL, FE, CU, PB, ZN CONCENTRATIONS IN THE SURFACE SEDIMENTS LEADING TO DISCRETE ZONES. THE POLLUTION LEVELS OF THE AREA IN TRACE METALS WERE ALSO EXAMINED. THE AREA IS NOT HEAVILY AFFECTED BY ANTHROPOGENIC INPUT BUT SOME TREND OF INCREASING CONCENTRATION LEVELS WERE OBSERVED. THIS FACT IMPLIES THE NEED FOR A CONTINIOUS CHEMICAL MONITORING.ΣΤΗΝ ΕΡΓΑΣΙΑ ΑΥΤΗ ΕΞΕΤΑΖΕΤΑΙ Η ΧΗΜΙΚΗ ΣΥΜΠΕΡΙΦΟΡΑ ΜΕΡΙΚΩΝ ΙΧΝΟΣΤΟΙΧΕΙΩΝ (AL,FE,MN,CU,PB,ZN) ΣΕ ΕΝΑ ΠΑΡΑΚΤΙΟ ΥΔΑΤΙΝΟ ΣΥΣΤΗΜΑ ΕΚΒΟΛΩΝ ΠΟΤΑΜΟΥ. ΜΕΛΕΤΑΤΑΙ, ΑΚΟΜΗ,Η ΔΙΑΚΙΝΗΣΗ ΤΟΥΣ ΜΕΤΑΞΥ ΤΗΣ ΔΙΑΛΥΤΗΣ ΦΑΣΗΣ, ΤΩΝ ΑΙΩΡΟΥΜΕΝΩΝ ΣΤΟ ΝΕΡΟ ΣΩΜΑΤΙΔΙΩΝ ΚΑΙ ΤΩΝ ΙΖΗΜΑΤΩΝ ΤΟΥ ΒΥΘΟΥ. ΓΙΑ ΤΗΝ ΜΕΛΕΤΗ ΕΠΙΛΕΧΘΗΚΕ ΕΝΑ ΑΠΟ ΤΑ ΠΙΟ ΕΝΔΙΑΦΕΡΟΝΤΑ ΤΕΤΟΙΑ ΣΥΣΤΗΜΑΤΑ ΣΤΗΝ ΕΛΛΑΔΑ, ΟΠΩΣ ΕΙΝΑΙ ΟΙ ΕΚΒΟΛΕΣ ΤΟΥ ΑΧΕΛΩΟΥ. ΓΙΑ ΤΗΝ ΕΚΤΕΛΕΣΗ ΤΗΣ ΜΕΛΕΤΗΣ ΣΧΕΔΙΑΣΤΗΚΕ ΕΝΑ ΔΙΚΤΥΟ ΣΤΑΘΜΩΝ ΔΕΙΓΜΑΤΟΛΗΨΙΑΣ, ΜΕ ΒΑΣΗ ΤΟ ΟΠΟΙΟ ΕΚΤΕΛΕΣΘΗΚΑΝ ΕΠΟΧΙΑΚΕΣ ΔΕΙΓΜΑΤΟΛΗΨΙΕΣ ΝΕΡΟΥ ΚΑΙ ΙΖΗΜΑΤΩΝ, ΜΕ ΧΡΗΣΗ ΕΙΔΙΚΩΝΣΥΣΚΕΥΩΝ. ΤΑ ΔΙΑΛΥΜΕΝΑ ΙΧΝΟΣΤΟΙΧΕΙΑ ΔΙΑΧΩΡΙΣΤΗΚΑΝ ΑΠΟ ΤΑ ΑΙΩΡΟΥΜΕΝΑ ΜΕ ΔΙΗΘΗΣΗΑΠΟ ΗΘΜΟΥΣ MILLIPORE O.45 MM. ΚΑΤΟΠΙΝ ΜΕΤΡΗΘΗΚΑΝ ΜΕ ΦΑΣΜΑΤΟΦΩΤΟΜΕΤΡΙΑ ΑΤΟΜΙΚΗΣΑΠΟΡΡΟΦΗΣΗΣ, ΜΕΤΑ ΑΠΟ ΠΡΟΣΥΓΚΕΝΤΡΩΣΗ ΣΕ ΡΗΤΙΝΕΣ CHELEX-100. ΟΙ ΗΘΜΟΙ ΜΕ ΤΑ ΑΙΩΡΟΥΜΕΝΑ ΣΩΜΑΤΙΔΙΑ ΚΑΙ ΤΑ ΙΖΗΜΑΤΑ ΚΑΤΕΡΓΑΣΤΗΚΑΝ ΜΕ ΠΥΚΝΟ ΝΙΤΡΙΚΟ ΚΑΙ ΑΡΑΙΟ ΥΔΡΟΧΛΩΡΙΚΟ ΟΞΥ, ΩΣΤΕ ΝΑ ΣΥΓΚΡΙΘΟΥΝ ΔΥΟ ΤΡΟΠΟΙ ΠΑΡΑΛΑΒΗΣ ΔΙΑΦΟΡΕΤΙΚΩΝ ΜΟΡΦΩΝ ΚΑΙ ΠΟΣΟΤΗΤΩΝ ΜΕΤΑΛΛΩΝ. Η ΤΕΛΙΚΗ ΜΕΤΡΗΣΗ ΚΑΙ ΕΔΩ ΕΓΙΝΕ ΜΕ ΦΑΣΜΑΤΟΦΩΤΟΜΕΤΡΙΑ ΑΤΟΜΙΚΗΣ ΑΠΟΡΡΟΦΗΣΗΣ. ΠΑΡΑΛΛΗΛΑ ΜΕΤΡΗΘΗΚΑΝ ΕΠΙ ΤΟΠΟΥ ΚΑΙ ΜΙΑ ΣΕΙΡΑ ΑΠΟ ΦΥΣΙΚΕΣ ΠΑΡΑΜΕΤΡΟΥΣ ΟΠΩΣ ΔΙΑΛΥΤΟ ΟΞΥΓΟΝΟ, ΘΕΡΜΟΚΡΑΣΙΑ, ΑΛΑΤΟΤΗΤΑ ΚΑΙ ΡΗ. ΤΑ ΑΠΟΤΕΛΕΣΜΑΤΑ ΤΩΝ ΜΕΤΡΗΣΕΩΝ ΕΠΕΞΕΡΓΑΣΤΗΚΑΝ ΣΕ ΗΛΕΚΤΡΟΝΙΚΟ ΥΠΟΛΟΓΙΣΤΗ, ΜΕ ΧΡΗΣΗ ΕΙΔΙΚΑ ΚΑΤΑΣΤΡΩΘΕΝΤΟΣ ΠΡΟΓΡΑΜΜΑΤΟΣ. Η ΕΠΕΞΕΡΓΑΣΙΑ ΑΥΤΗ ΕΔΕΙΞΕ ΜΙΑ ΣΕΙΡΑ ΑΠΟ ΣΗΜΑΝΤΙΚΕΣ ΧΗΜΙΚΕΣ ΔΙΕΡΓΑΣΙΕΣ, ΠΟΥ ΛΑΜΒΑΝΟΥΝ ΧΩΡΑΝ ΣΤΗ ΔΙΑΡΚΕΙΑ ΤΗΣ ΑΝΑΜΙΞΗΣ ΓΛΥΚΩΝ-ΑΛΜΥΡΩΝ ΝΕΡΩΝ. OΙ ΚΥΡΙΩΤΕΡΕΣ ΑΠΟ ΑΥΤΕΣ ΕΙΝΑΙ, Η ΜΕΤΑΦΟΡΑ ΡΒ ΚΑΙ ΖΝ ΑΠΟ ΤΗ ΔΙΑΛΥΤΗ ΣΤΗ ΣΩΜΑΤΙΔΙΑΚΗ ΦΑΣΗ, Η ΑΥΞΗΣΗ ΤΩΝ ΣΥΓΚΕΝΤΡΩΣΕΩΝ ΤΩΝ ΔΙΑΛΥΤΩΝ ΜΕΤΑΛΛΩΝ ΣΤΟ ΘΑΛΑΣΣΙΝΟ ΝΕΡΟ, Η ΑΥΞΗΣΗ ΤΩΝ ΣΥΓΚΕΝΤΡΩΣΕΩΝ ΤΟΥ ΜΝ ΚΑΙ ΤΟΥ ΖΝ ΣΤΑ ΙΖΗΜΑΤΑ ΚΟΝΤΑ ΣΤΟ ΣΤΟΜΙΟ ΤΟΥ ΠΟΤΑΜΟΥ, ΚΑΘΩΣ ΚΑΙ ΟΙ ΑΝΑΛΟΓΕΣ ΚΑΤΑΝΟΜΕΣ ΤΩΝ AL,FE,CU,PB,ZN ΣΤΑ ΕΠΙΦΑΝΕΙΑΚΑ ΙΖΗΜΑΤΑ ΤΗΣ ΠΕΡΙΟΧΗΣ . ΜΕΛΕΤΗΘΗΚΕ ΕΠΙΣΗΣ ΚΑΙ Η ΡΥΠΑΝΣΗ ΤΗΣ ΠΕΡΙΟΧΗΣ ΑΠΟ ΤΑ ΕΞΕΤΑΣΘΕΝΤΑ ΙΧΝΟΣΤΟΙΧΕΙΑ, Η ΔΕΝ ΒΡΕΘΗΚΕ ΝΑ ΕΙΝΑΙ ΣΗΜΑΝΤΙΚΗ, ΑΝ ΚΑΙ ΑΝΙΧΝΕΥΤΗΚΑΝ ΤΑΣΕΙΣ ΑΥΞΗΣΗΣ ΤΩΝ ΣΥΓΚΕΝΤΡΩΣΕΩΝ ΤΟΥΣ

Nitrogen and Phosphorus Loads in Greek Rivers: Implications for Management in Compliance with the Water Framework Directive

Reduction of nutrient loadings is often prioritized among other management measures for improving the water quality of freshwaters within the catchment. However, urban point sources and agriculture still thrive as the main drivers of nitrogen and phosphorus pollution in European rivers. With this article we present a nationwide assessment of nitrogen and phosphorus loads that 18 large rivers in Greece receive with the purpose to assess variability among seasons, catchments, and river types and distinguish relationships between loads and land uses of the catchment. We employed an extensive dataset of 636 field measurements of nutrient concentrations and river discharges to calculate nitrogen and phosphorus loads. Descriptive statistics and a cluster analysis were conducted to identify commonalties and differences among catchments and seasons. In addition a network analysis was conducted and its modularity feature was used to detect commonalities among rivers and sampling sites with regard to their nutrient loads. A correlation analysis was used to identify major possible connections between types of land uses and nutrient loads. The results indicated that the rivers Alfeios, Strymonas, and Aliakmonas receive the highest inorganic nitrogen loads while the highest inorganic phosphorus loads were calculated for the rivers Strymonas, Aliakmonas, and Axios. Concerning the temporal variation of loads, inorganic nitrogen presented a peak on March and gradually declined until October when the dry period typically ends for most regions of Greece. Inorganic phosphorus loads had the highest average value in August and the lowest in October. Thus, our findings confirmed the presence of a typical seasonal variation in nitrogen loads that follows the seasonality in hydrology where high surface runoff during the wet months contribute to higher river discharges and higher nitrogen loads from the catchment. On the contrary, high phosphorus loads persisted during dry months that could be attributed to a dilution effect. Furthermore, the results imply a clear connection between agriculture and both nitrogen and phosphorus. Overall, this work presents extensive information on the nitrogen and phosphorus loads that major rivers in Greece receive that can largely aid water managers to adapt and revise basin management plans in accordance with agricultural management (e.g., which months farmers should reduce the use of fertilizers) with the purpose of meeting the environmental targets defined by the Water Framework Directive (WFD)

Occurrence and tissue distribution of perfluoroalkyl substances (PFASs) in sharks and rays from the eastern Mediterranean Sea

Persistent organic pollutants (POPs), including Perfluoroalkyl substances (PFASs), enter into the marine ecosystem, raising questions on possible adverse effects caused to the health of marine organisms and especially of top predators. Thus, there is an urge to assess the occurrence and the tissue distribution of PFASs in apex predators. To this end, the current study examines concentrations and distribution of 15 PFASs among 85 samples of different tissues from 9 shark and ray species collected in Greece. The results showed a similar PFAS pattern among the different tissues, with long carbon chain PFASs being the most frequently detected compounds. PFTrDA was the most predominant compound in terms of concentration and frequency of detection, followed by PFUnDA and PFOS. PFTrDA concentrations ranged between heart > liver ≈ gills > muscle. Relative contribution (%) of individual compounds to ΣPFAS concentration varied among the different shark tissues, and also among the different shark species. No correlation between PFASs levels in tissues and sharks’ gender, length and geographical origin was observed. This is the first study providing PFASs data in sharks collected from Greece and the first study comparing concentrations and patterns in 85 individual tissues from 9 different shark species.</p

Perfluoroalkylated substances (PFASs) in home and commercially produced chicken eggs from the Netherlands and Greece

Dietary intake is a major route of human exposure to perfluoroalkylated substances (PFASs). However, the available information on PFAS levels in food, including chicken eggs, is limited. In the present study, home produced and commercially produced eggs (organic, battery and free range eggs) were collected from the Netherlands (n = 95) and Greece (n = 76). The egg yolks were analysed for 11 PFASs by liquid chromatography-tandem mass spectrometry using isotope dilution. PFAS levels in yolk were higher in home produced eggs from the Netherlands (median 3.1, range <LOQ - 31.2 ng g-1) and Greece (median 1.1, range <LOQ - 15.0 ng g-1) compared to the eggs collected from supermarkets. In these eggs, all PFAS levels were below the LOQ of 0.5 ng g-1, except for a small amount of perfluorooctane sulfonate (PFOS) in 1 sample in each country (1.1 ng g-1 and 0.9 ng g-1 for the Netherlands and Greece respectively).PFOS was the predominant PFAS, making up on average 85% of ∑PFASs. The highest PFOS concentration was detected in a Dutch home produced egg sample (24.8 ng g-1). The contamination pattern was similar in both countries with the long-chain PFASs (C ≥ 8) being most frequently detected, while short-chain PFASs were rarely found. The most likely cause of the contamination of home produced eggs is ingestion of soil through pecking. Although regular consumption of home produced eggs will lead to an increased PFOS exposure, it is not expected that it will lead to exceedance of the tolerable daily intake established by EFSA

Occurrence of perfluoroalkyl substances (PFASs) in a large number of wild and farmed aquatic animals collected in the Netherlands

A range of perfluoroalkyl substances (PFASs) was analysed in marine fish, farmed fish, crustaceans, bivalves and European eel caught in (mostly) Dutch waters, or purchased at Dutch markets (approximately 250 samples, collected between 2012 and 2018). ΣPFAS levels were highest in eels collected from rivers and lakes (average 43.6 ng/g and max 172 ng/g), followed by shrimps collected near the Dutch coast (average 6.7 and max. 33 ng/g ww), and seabass (average 4.5 and max. 9.4 ng/g ww). Most of the farmed fish (e.g. trout, catfish, turbot, salmon, tilapia, pangasius) were among the lowest contaminated samples in this study (averages ranged from 0.06 to 1.5 ng/g ww). Geographically, levels in marine fish from the northern North Sea (e.g. haddock, whiting, herring) were lower than in the central and southern North Sea (e.g. cod and flatfish). Concerning eel, no substantial geographical differences were found (apart from two distinct locations). The contamination pattern was similar in all species, where PFOS mostly dominated the profile, and other long-chain PFASs being frequently detected. Short-chain PFASs were rarely found. PFOS concentrations in eel varied from 3.3 ng/g (close to the North Sea) to 67 ng/g ww in eel caught from Ghent-Terneuzen canal. The majority of detected PFOS levels in eels (93%) and 1 shrimp sample from Eems-Dollard exceeded the EU Environmental Quality Standard (EQS) for surface water of 9.1 μg/kg ww. Other samples (e.g. shrimps, bivalves, flounder), subject to the EQS, did not exceed this level