Determination of persistent organic pollutants in sediment and fish of the western coast of Alexandria,Egypt

Persistent organic pollutants (POPs) were recorded in sediment and fish samples collected from the western coast of Alexandria. Total hydrocarbons (aliphatic+PAHs ) in sediment ranged from 683.8 to 34670.1 ng g ^?1 with an average of 9286.9 ng g ^?1. The sum of C16–C34 of aliphatic fractions was<4000?ng g;^?1, indicating the presence of a fresh petroleum source. For all sediments, the anthracene/phenanthrene ratio was>0.1, suggesting the dominance of a pyrolytic source. Total aliphatics in different fish species ranged from 253 to 11?132 ng g;^?1, while total PAHs ranged from 3862 to 35?746 ng g;^?1 wet weight. Benzo[a]pyrene was the most dominant PAH fraction ranged from 1902.7 to 32 905.5 with an average of 9464.5?ng g;^?1 wet weight in all fish species. Concentrations of polychlorinated biphenyls (PCBs) ranged from 0.79 to 64.9?ng g;^?1 with an average 12.14?ng g;^?1 wet weight. The concentrations of organochlorines in fish species (Euthynnus alleferatus, Scomberomorus commerson, Sphyraena Sphyraena, Diplodus vulgaris, and Alepes djedaba) decreased following the order: PCBs>DDTs>HCHs>total cyclodienes. Concentrations of DDTs in fish tissues ranged from 4.89 to 36.37 ng g^?1 with an average of 16.4?ng g;^?1 wet weight. The concentrations of total HCHs ranged from 0.3 to 65.7?ng g;^?1 with an average of 16.35?ng g;^?1. The present study indicates: (1) fresh petroleum input where Pr/Ph>1; (2) PAHs in sediment<4000 ng g ^?1; (3) BaP concentration exceeded the permissible levels in Alepes djedaba species; (4) DDTs in sediment were below the effective range low level; (5) PCBs>effective range low and相似文献   

Tributyltin pollution in sediments from Alexandria's coastal areas

Presence of Tributyltin (TBT) in Alexandria’s coastal water areas has been demonstrated by measuring concentrations of this compound. The TBT was measured in sediments from three docking areas namely: Western Harbour, Eastern Harbour and Abu Qir Bay. The sediment of those areas has been affected by marine traffic and other industrial activities. This is reflected by the distribution of TBT in the sediments nearby the shipyards in the three docking areas of the region where the average values of 258.6 ηg TBT/g for Western Harbour; 126.4 ηg TBT/g dw for Abu Qir Bay and 42.3 ηg TBT/g dw for the Eastern Harbour were recorded. This fact reflects the effect of industry and marine traffic on the marine environments of the Alexandria region.     

Tributyltin pollution in sediments from Alexandria's coastal areas

Presence of Tributyltin (TBT) in Alexandria's coastal water areas has been demonstrated by measuring concentrations of this compound. The TBT was measured in sediments from three docking areas namely: Western Harbour, Eastern Harbour and Abu Qir Bay. The sediment of those areas has been affected by marine traffic and other industrial activities. This is reflected by the distribution of TBT in the sediments nearby the shipyards in the three docking areas of the region where the average values of 258.6 ηg TBT/g for Western Harbour; 126.4 ηg TBT/g dw for Abu Qir Bay and 42.3 ηg TBT/g dw for the Eastern Harbour were recorded. This fact reflects the effect of industry and marine traffic on the marine environments of the Alexandria region.     

Levels of tin in core sediments along the Alexandria Coast, Egypt

Tin concentrations were determined in surface and core sediments from three hot spots along the Alexandria coast, namely: Abu-Qir Bay, Eastern Harbour, and Western Harbour. The mean concentrations in surface sediment were 2.434, 3.212, and 5.572 μg/g dry weight for Abu-Qir Bay, Eastern Harbour, and Western Harbour, respectively. A sharp decrease in tin level in core sediments with depth was observed in almost all locations except for core 4 in Abu-Qir Bay and core 17 in the Eastern Harbour, where the sub-sample at the 5 cm level recorded the highest tin concentrations.     

Ecotoxicity studies of some organotin compounds

The ecotoxicities of three organic compounds containing spacer groups, an intermediate organotin premonomer, four organotin monomers, their homopolymers and six copolymers of tributylin α‐chloroacrylate (TCA) are reported against two microorganisms viz., Pseudomonas aeruginosa and Sarcina lutea and a larval species Anemia salina (Nauplii II). The organic compounds containing spacer group were less toxic whereas the monomers were found to be highly toxic. The homopolymers were found to be more toxic than that of tributyltin acrylate (TBTAA), tributyltin methacrylate (TBTMA) and tributyltin α‐Chloroacrylate (TCA). The toxicity of TCA copolymers increased with the increase in tributyltin (TBT) content in the polymer. From this study it was not possible to establish any relationship between the chemical nature of the comonomer with its toxicity.     

Assessment of Trace Metals in the Sediments From the Coastal Zone of Alexandria, Egypt

Freshly deposited surface sediments from the Alexandria coastal zone were collected and analysed in 1995 for their trace metal concentrations. Metal concentrations in the sediments vary between sites within a wide range for copper, zinc, iron, lead, chromium and cadmium. the statistical analysis between the metal concentrations and the different constituents (organic carbon, total nitrogen, silt, clay and total iron) showed significant correlations. the enrichment factors for the sediments ranged between 3 and 4-fold for copper, chromium and zinc and reached up to 9-fold for lead and 113-fold for cadmium. the highest index for cadmium and lead may be attributed to the anthropogenic inputs from the surrounding area, where they are highest in lower discharge areas.     

Assessment of Trace Metals in the Sediments From the Coastal Zone of Alexandria,Egypt

Freshly deposited surface sediments from the Alexandria coastal zone were collected and analysed in 1995 for their trace metal concentrations. Metal concentrations in the sediments vary between sites within a wide range for copper, zinc, iron, lead, chromium and cadmium. the statistical analysis between the metal concentrations and the different constituents (organic carbon, total nitrogen, silt, clay and total iron) showed significant correlations. the enrichment factors for the sediments ranged between 3 and 4-fold for copper, chromium and zinc and reached up to 9-fold for lead and 113-fold for cadmium. the highest index for cadmium and lead may be attributed to the anthropogenic inputs from the surrounding area, where they are highest in lower discharge areas.     

Mercury concentrations in the surface sediments of the intertidal area along the west coast of Peninsular Malaysia

Total mercury (Hg) levels in the intertidal surface sediments along the west coast of Peninsular Malaysia were analysed by using heat vaporization method. Total Hg levels in these sediments ranged from 3.00 to 201?µg?kg^?1 dry weight with a mean concentration of 60.0?µg?kg^?1 dry weight. More than 90% of the samples studied have the total Hg concentrations less than 150?µg?kg^?1 dry weight. Compare with the regional data and sediment quality guidelines, the Hg contamination in the intertidal area along the west coast of Peninsular Malaysia was not serious, except for a few sites that might have received anthropogenic Hg in the samples collected between 1999 and 2000. It is suggested that a similar study of heavy metals in the sediments of the west coast of Peninsular Malaysia be conducted regularly.     

Occurrence of the Dinoflagellate Gymnodinium Catenatum (Graham) Along the Mediterranean Coast of Alexandria (Egypt)

A monitoring programme during 4 years (1993-1996) was established in four eutrophic marine basins along the Mediterranean coast of Alexandria (Egypt) to follow the occurrence of a newly recorded dinoflagellate Gymnodinium catenatum and ambient environmental conditions. the species achieved its massive occurrence in warm seasons at low salinity, density stratified water column and different nutrient concentrations. A simple statistical approach showed temperature and phosphate to effect its distribution. Apparently no cases of toxic effect have accompanied the occurrence of G. catenatum. the regular occurrence of the species during the 4 year survey mean the existence of its benthic resting cysts, which certainly have important implications for its distribution dynamics.     

Trace metals in fish of economic interest from the west of Alexandria,Egypt

The concentration of some heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn) in the muscle, liver, and gills in eight fish species, Caranx crysos, Euthynnus alleferatus, Scomberomorus commerson, Sphyraena viridensis, Sargus sargus, Siganus rivulatus, Mugil species, and Sardinella aurita were collected seasonally from the Mediterranean Sea in the region of Alexandria. The highest concentrations of Cd, Cu, Fe, and Zn were measured in liver tissue, while gill tissue yielded the highest concentrations of Mn, Ni, and Pb. Muscle is the organ of poor accumulation factor for all metals under investigation. Concentration of cadmium in muscle in Mugil species exceeds the permissible limit in summer, while Siganus rivulatus exceeds it in the summer and autumn seasons. On the other hand, copper, nickel, lead, and zinc are still much lower than the permissible levels. The metal pollution index (MPI) for metals was studied, revealing that Siganus rivulatus, Mugil species and Sardinella aurita had the highest MPI. Provisional tolerable daily intake (PTDI) indicates that the concentration levels of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in the muscle of all fish species under investigation are much lower than recommended PTDI values, and accordingly there is no risk for the human consumption of these fish species.     

Heavy-metal distribution and risk assessment of sediment and fish from El-Mex Bay, Alexandria, Egypt

Heavy metals are increasingly being released into natural waters from geological and anthropogenic sources. The distribution of several heavy metals (Cr, Cu, Cd, Pb, Zn, and Hg) was investigated in muscle, gill, and liver in two different fish species seasonally collected in El-Mex Bay (autumn 2004-summer 2005). In order to evaluate the pollution status of the Bay, the concentrations of the selected metals in the labile and total fractions were analysed in sediment samples collected from eight sites in El-Mex Bay during autumn 2004. Also, the Index of Geoaccumulation (I_geo) for the sediment was estimated. The total and labile fractions of the selected metals in sediment samples were 15.2 and 62.8 μg g^-1 dw for Cu, 1.8 and 5.0 μg g^-1 dw for Cd, 79.1 and 130.3 μg g^-1 dw for Zn, 0.2 and 1.2 μg g^-1 dw for Hg, 35.8 and 93.0 μg g^-1 dw for Pb, and 13.9 and 31.0 μg g^-1 dw for Cr. The concentrations of all metals were lower in flesh than those recorded in liver and gill due to their physiological roles. The metal pollution index for fish was calculated. Health hazard calculations for the contaminated sediments and fish consumption were calculated to evaluate the effect of pollution on health.     

A preliminary model of nutrient cycling in sediments of a Mediterranean lagoon

A model of nitrogen and phosphorus cycles in the sediment of a lagoon has been developed. This model was applied to the Thau lagoon (southern France). Sediment was sliced in three layers to reproduce the oxygen profile, which is simulated within the model. Following an equilibrium hypothesis, the model was calibrated against field data. State variables and fluxes were estimated in the sediment and across the sediment-water interface. A Monte Carlo sensitivity analysis was performed to determine the most sensitive parameters and sediment state variables. A dynamic simulation with varying oxygen concentrations then showed the influence of anoxia on the phosphorus and nitrogen fluxes between water and sediment.     

Quantitative investigations of sand-bottom macrofauna along the Mediterranean north-west coast

Consideration of the range of quantitative data collected in a 4 year survey of macrobenthic fauna in sublittoral fine-sand on the north-west Mediterranean coast allows some farreaching comments. As a diver-operated suction sampler was employed, density and biomass values obtained must be considered as the most accurate ones for such hard ground. The wide range of values observed from bay to bay and from year to year suggests different controlling factors. Among environmental factors, influence of exposure is clearly shown, and trophic conditions offered to filter and suspension feeders by the water column in controlling high biomass values is emphasized. Among biological factors, high growth and generation replacement rates for main species together with a high predation-rate explain changes and instability in fauna-assemblage structures of Mediterranean fine-sand macrofauna. Comparison of these biological data with those from northwest European shallow-sand associations reveals some important differences which suggest some restrictions to the parallel level-bottom community concept.     

AVS-SEM relationships and potential bioavailability of trace metals in sediments from the Southeastern Mediterranean sea,Egypt

In risk assessment of aquatic sediments, much attention is paid to the difference between acid volatile sulfide (AVS) and simultaneously extracted metals (SEM) as indicators of metal bioavailability. Distribution of AVS and SEM (Cd, Cu, Ni, Pb and Zn) were determined in 20 representative sampling sites collected along the Egyptian Mediterranean coast. Total SEM concentration [ΣSEM] ranged from 0.012 to 0.241 μmoleg^?1. AVS concentrations were much more variable, showing significant spatial variations. The values ranged from 0.015 to 31.326 μmoleg^?1. The different relationships between AVS and SEM to establish mechanical models such as the ratio of ΣSEM and AVS [ΣSEM/AVS], the difference between the ΣSEM and AVS [ΣSEM–AVS], or the organic carbon normalised difference between SEM and AVS [ΣSEM-AVS]/f_oc models were used as parameters to evaluate potential bioavailability. Considering SEM/AVS model, sediments at the Western Harbour, Eastern Harbour, Ras El-Burr, El-Gamil East, and Port Said stations are occasionally toxic, while according to SEM-AVS model, no indication of associated adverse toxic effect would occur at any of the sampling sites. Calculated [ΣSEM-AVS]/f_oc was<130 μmoleg^?1 in the sediments indicating that sediments should pose a low risk of adverse biological effects owing to cadmium, copper, lead, nickel and zinc. Association of adverse effects to aquatic organisms was determined, using the classification of the sediments according to the Sediment Quality Guidelines (SQGs). The marine Threshold Effect Levels (TEL) and Probable Effect Levels (PEL) were used in this work and in order to obtain a more realistic measure of predicted toxicity, mean PEL quotients (PELq) were calculated. The mean PELq calculated for the sampling sites was (0.11–1.5) and categorised as slightly toxic at all stations except Baghoush, Nobarreya and western harbour, which had PELq<0.1 and categorised as non-toxic. The obtained data concluded that the remobility and bioavailability of trace metals contained in surfacial sediments of the Egyptian Mediterranean coastal area are low.     

The formation of protective dune ridge along the Southeast Baltic Sea coast: historical and social aspects

This paper is based on literature-based studies, as well as material collected by the author over more than 30 years on the shores of the Southeast Baltic Sea. In order to protect roads running along the shoreline from East Prussia to Königsberg, local shore reinforcement works commenced in the fifteenth century, although some individual attempts had been made before. In 1684, M. Ch. Hartknoch theoretically substantiated the necessity for, and methods of, shore reinforcement. The state of the shores deteriorated considerably during the Seven Years War (1756–1763), when woodlands growing along the shores were completely destroyed; hence, nearly 100 km length of the coast of the Kur?i? Nerija (Curonian) sand spit was left without any vegetation. Aeolian sand buried as many as fourteen settlements. This situation forced the authorities to organise maintenance of the coast and the dunes at the governmental level, and to start the formation of an uninterrupted dune ridge. The second half of the nineteenth century and the first half of the twentieth century are notable for the extensive construction of new ports. Along the shores running from the Sambian Peninsula to the Gulf of Riga, eight port engineering structures had been constructed with the intervals of approximately 26 km between the ports of Klaip?da and Liepaja, and every 13 km between Palanga and Pape. Shore management measures were being implemented simultaneously, thus ensuring the functioning of the above-mentioned coastal protection structures and the reduction of impacts upon the shores. In the second half of the twentieth century, ports were dredged and developed significantly. Their entrance channels reduced the long-shore sediment transport. Moreover, total sand reserves in the shore zone also diminished. The processes of erosion of the beaches and the dune ridge made it necessary to actively reinforce the shore. A number of countries passed legal acts governing the protection and use of the shore zone. At the turn of the twenty-first century, the incompatibility of such priorities in human activities as sea transport and recreation with nature protection has become evident. The conflict of interests in the Kur?i? Nerija National Park, the port of Klaip?da, and the resort of Palanga serve as good examples of such incompatibility. The conclusion that can be drawn that in twenty-first century is that the priorities in general coastal management should be as follows: harmonisation of interests among the states and individual fields of activities, as well as measures aimed at neutralisation of negative natural trends (higher frequency of storms, global rise of water level, etc.). The protective beach dune ridge will further play the role of efficient means for reducing shore erosion.     

Comparative study of heavy metal distribution in some coastal seaweeds of Alexandria, Egypt

The distribution of Cd, Cu, Fe, Hg, Mn, Ni, Pb, and Zn concentration in five algae species (Enteromorpha intestinalis, Enteromorpha linza, Ulva lactuca, Corallina mediterranea, Pterocladia capillacea) collected from three areas having different types of metal contamination along Alexandria coastal waters (Egypt) were determined by Atomic Absorption Spectrometry. The recovery study was carried out using a Certified Reference Material TORT-2. The obtained heavy metal contents indicate that different species demonstrate various degree of metal accumulation. Enteromorpha intestinalis (green algae) recorded the highest levels of Fe and Mn while Corallina mediterranea (Calcareous red algae) recorded the highest concentration of Pb, Ni, and Cd in the three areas under study. According to the present study, filamentous algae (Enteromorpha intestinalis) showed the ability to concentrate greater amount of trace elements than the foliaceous ones (Enteromorpha linza). In each area, mercury concentration has nearly the same value for all species under study.     

Effect of selenium on mercury methylation in facultative lake sediments

The effect of selenium (Na₂SeO₃) on the methylation of mercury (HgCl₂) in facultative sediment was studied. The results showed that small amount of selenium (0.25 μg/g) added to the sediment could significantly reduce the net methylation rate of mercury. The more the selenium was added, the higher the inhibition effect was. These results made the addition of selenium to the aquatic systems more practical and safe as a way to alleviate mercury accumulation in fish. Additionally, higher temperature was favorable to the net methylation of mercury, and high concentration of methylmercury emerged earlier.     

First monospecific bloom of the harmful raphidophyte Chattonella antiqua (Hada) Ono in Alexandria waters related to water quality and copepod grazing

The massive red tide bloom of Chattonella antiqua that occurred in Alexandria waters during late August/early September 2006 was monospecific, of very high density, and of wide spatial distribution, and was accompanied by mass fish and invertebrates mortalities. During the bloom, surface water temperature ranged between 26.5 and 28.5 °C and salinity between 23 and 27 psu. The bloom started under very high nitrate and ammonia levels; where the uptake of ammonia seemed to be faster than that of nitrate, and the bloom seemed to avoid the copepod grazing. Mass fish and invertebrates mortality was observed. Few cells of Heterosigma species have been reported for the first time in the Alexandria waters. Several environmental constraints (including physical factors), nutrient loading, copepod grazing and comparison with other data for C. antiqua blooms in Alexandria waters are also discussed.     

Speciation analysis of butyltin compounds in sediments of the Theoule harbour (France) by GC/AES

Over the last years, great progress in the research on speciation of butyltins has been made. Many coupling techniques have been successfully developed, with better applications to sediments samples in the environment. Sediments were collected from 1999 to 2000 to elucidate butyltin pollution in Theoule harbour. Most of the analysed samples showed evidence of butyltin compounds. The results show that the concentration of Tributyltin (TBT) was in the range 20–200?µg/kg in March 1999, 20–340?µg/kg in June 1999, 180–1280?µg/kg in July 2000, and 55–820?µg/kg in October 2000. A comparison of the MBT, DBT, and TBT results show that in 1999 the concentrations were in the order TBT?DBT?>?MBT, with some exceptions. The patterns observed in many sediment cores show a great disparity of organotin input concentration among the cores collected during one month and also during two different months, and from one season to the other. This paper provides information on the use of the acetic acid leaching system in the determination of butyltin. The method is applied to evaluate the occurrence of these species in sediments from the Theoule harbour, between 1999 and 2000. In this study, a GC/AES was applied, complemented with acetic acid leaching and monitored using two certified reference materials: PACS-2 reference sediment and BCR 462 (Report EUR 18406 EN, 1998).     

Geochemistry of heavy metals in bottom sediments from streams of the western coast of the rio de la plata estuary, Argentina

The fluvial system within the southwestern coastal sector of the Río de la Plata interacts with a very large and efficient mixing basin known as the Río de la Plata estuary. The region is a densely populated and productive sector of Argentina and is characterised by a temperate humid climate. The streams Carnaval, Martín, Del Gato and El Pescado of the study area drain two main geomorphologic units: a higher inner zone and the low lands of the coastal plain. In particular, the Del Gato stream receives heavily polluted discharges from agricultural, urban and industrial point and non-point sources of pollution, while the other streams collect a lower and variable discharge input. As a part of an initial assessment of the role of fluvial bottom sediments in the fate of metals through the stream ecosystems, the spatial distribution of trace and major elements related to particles in the accumulation areas was examined. Concentration of Cr, Ni, Cu, Zn, Cd, Hg, Pb, Fe and Mn, grain size, mineralogy (clay-X ray diffraction) and organic matter content were analysed in the four streams considering both geomorphologic units at different depositional time. Untreated and iron-normalised trace metal concentrations in the most polluted streams show higher levels in the upper layers of most contaminated sectors and accumulation areas associated to topographic low lands. The coastal plain sector behaves as a regional sink between the upstream area and the estuary.