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A novel mesoporous chitin blended MoO3-Montmorillonite nanocomposite was prepared through three-steps synthesis. First, chitin was extracted from prawn shell then MoO3-MMT was prepared, and lastly, chitin was blended with MoO3-MMT. Chitin-MoO3-MMT was applied for the removal of Cu(II) and Pb(II) from wastewater. XRD characterization revealed MoO3 solubility in MMT interlayers, SEM showed a nanocomposite formation with sharp nanorods like-structure and length ranging from 60 to 77.7 nm. FTIR exhibited fundamental changes in the surface functional groups after adsorption. XPS analysis before and after adsorption showed the domination of chemical bonding with N and O. N2 adsorption-desorption isotherm displayed H3-type hysteresis loop and a pore size diameter of 10.67 nm confirming the mesoporous nature. Adsorption efficiency was studied as a function of pH, time, metal concentration and adsorbent mass. Adsorption capacity (Qe) values were 19.03 and 15.92 mg.g−1 for Cu(II) and Pb(II) respectively. The metal surface coverage mapping was 1.87 × 10^19 and 4.34 × 10^18 atoms/m2 for Cu(II) and Pb(II) respectively. Adsorption followed Langmuir isotherm and pseudo-second-order (PSO) kinetics suggesting a monolayer chemisorption domination. Intraparticle diffusion (IPD) model showed a boundary layer control. Thermodynamically, the adsorption was spontaneous and endothermic with activation energies 25.94 and 29.37 kJ.mol−1 for Cu(II) and Pb(II) respectively.

A variety of biomarker and non-biomarker parameters has been used to geochemical characterization of seven crude oils from the Gulf of Suez region of Egypt. The carbon number distribution and the i...

Due to the scarcity of drinking water, the city of Tobruk depends mainly on desalination of sea water for drinking. The water quality of 16 sites along Tobruk bay was investigated during two seasons (winter and summer). Varying analytical techniques have been utilized to analyze group of environment-sensitive elements, including Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. These tests were performed using the Inductively Coupled Plasma/Atomic Emission Spectroscopy ICP/AES. To evaluate the suitability of water for aquatic life and drinking purposes the contamination index (Cd) was computed. The results of the present study indicated the bay is affected by intensive load of urban, agricultural and industrial wastewater showed serious deterioration of water quality compared with other sites along the Mediterranean Sea. The studied sites of Tobruk bay showed high Cd values which associated with high risks, where, most of the studied metals often exceeded the drinking water and aquatic life permissible limits as compared with WHO specifications, as well as Libyan specifications.

The Arab Petroleum Pipelines Company “SUMED” is a joint stock company that owns and operates two parallel pipelines Ain Sukhna on the Red Sea to Sidi Kreir on the Mediterranean. A huge tanks farm at each oil terminal, which serves operation. Daily routine operations may cause some environmental risks. Although relatively rare, major accidental oil spills do happen and can potentially cause a major impact on marine environment.

In this work five surface sediments samples and seven surface water samples were collected from specifically chosen locations in the vicinity of Sidi Kreir area which is considered a hot spot area in the Mediterranean Sea due to presence of power station, The Arab Petroleum Pipelines Company “SUMED” as well as increasing the movement of ships that are transferring oil and its derivatives. A total of thirteen Polycyclic Aromatic hydrocarbons (PAHs) were determined in sediment and water samples in order to study the adverse environmental and health effects. The concentration of total PAH ranged from 249.62 ng.l−1 to 556.56 ng.l−1 dry wt. and from 41.96 ng.l−1 to 292 ng.l−1 in sediment and water respectively.

The Tobruk Bay represents great commercial and economic importance as a result of population growth, urban development, economic and industrial activity. Large quantities of municipal and industrial waste are disposed directly in seawater. Heavy metals are the most important and most serious problems in aquatic environments. This study was conducted to evaluate the concentrations of heavy metals contamination and their distribution in the sediments. Sixteen sites were selected and identified accurately representing the study area. Samples placed in self-closing polyethylene bags and stored in ice boxes then transfer to the laboratory, they stored in the refrigerator at −20 ℃ in the dark until analysis. The ICP-OES instrument was used to detect the desired heavy metals (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in the surface sediment samples. The ranges of TOC and the fine fraction (clay and silt) contents of analyzed sediments are 2.2%–4.7% and 0.2%–1.7%, respectively. Their average values are 3.3% and 0.8%, respectively. The comparison of heavy metal concentrations in this study with that of previous studies in other regions shows that the concentration of heavy metals in surface sediments of Tobruk bay is lower than concentrations of heavy metals in Western Xiamen Bay, China, New York Harbor, Bremenn Harbor Germany, Izmir Harbor, Turkey regions. The calculated results of Igeo values indicated that all the sampling stations were extremely polluted with As, also enrichment factor revealed the same results.

A novel mesoporous chitin blended MoO

Organic–inorganic hybrid nanocomposites are promising materials for remediation of pollutants from wastewater, as they exhibit the unique characteristics of both inorganic and organic materials. In this study, carboxymethyl cellulose/montmorillonite Nanocomposite (CMC/MMT-NC) was prepared and applied for Cu2+ sequestration. CMC/MMT-NC was characterized by FTIR and SEM before and after the sequestration process, indicating fundamental changes in surface morphology after treatment experiments. The parameters affecting the process such as pH, contact time, CMC/MMT-NC mass, Cu2+ concentration and temperature were experimentally adjusted. Statistical regression variables (R2, RMSE, RSS, F-Value and P-Value) were calculated to predict the best-applied isotherm, kinetic and thermodynamic modeling. Freundlich isotherm model successfully described the equilibrium data, which implies a multilayer adsorption process. Kinetic results were well fitted to pseudo-second-order kinetic model. Intraparticle diffusion (IPD) model showed the control of the boundary layer moreover, IPD model cannot be accepted as the only rate-determining step. The apparent activation energy (Ea) was 35.65 kJ/mol, which revealed a physisorption process. The thermodynamic study in means of ΔG0, ΔH0, and ΔS0 demonstrated the feasibility, spontaneity and exothermicity of Cu2+ sequestration. Application study confirmed the efficiency of CMC/MMT nanocomposite to remediate Cu2+ from synthetic and natural polluted seawater.

Gas chromatography and combined gas chromatography/mass spectrometry were used to characterize different thiophenic compounds in representative petroleum from the Gulf of Suez. An evaluation of the distribution patterns of these compounds has been used to infer depositional environment and lithology of crude oil source rock and maturity. Ratios involving dibenzothiophenes (DBT) such as DBT/phenanthrene (Phen) and methyldibenzothiophenes (MDBT)/methylphenanthrenes (MPhen) correlated with other biological markers and were used to classify the oils into different source-related types. Type 1 oils with relatively high (DBT/Phen) and (MDBT/MPhen) ratios show marine carbonate depositional setting. Type 2 oils show low (DBT/Phen) and (MDBT/MPhen) ratios and other biomarker features consistent with marine siliciclastic source rocks. On the other hand, type 3 oils have geochemical characteristics intermediate between those of types 1 and 2.

The coastal waters of Al-Mukalla, Hadramout Governate, Republic of Yemen, receive considerable amounts of treated and untreated domestic and industrial effluents, which carry a variety of contaminants including heavy metals. We surveyed benthic foraminiferal assemblages as potential indicators for pollution and collected geochemical, sedimentological and water-quality data. Cluster and canonical correspondence analyses delineated three areas: unpolluted areas east and west of Al-Mukalla harbor (biofacies I), a moderately polluted area in and around the harbor (biofacies II), and a highly polluted site within the main harbor (biofacies III). Biofacies I is characterized by sandy sediments with moderate proportions of CaCO 3 , low total organic matter and low heavy metal concentrations. This biofacies is characterized by pollution-sensitive smaller species ( Ammonia parkinsoniana , Discorbinella bertheloti and Pararotalia nipponica ). Biofacies II includes sites exposed to southwest monsoon winds, which are characterized by coarse sand relatively rich in CaCO 3 , as well as more protected sites that are somewhat more muddy, with somewhat higher concentrations of organic matter and heavy metals. Foraminiferal assemblages include larger taxa ( Amphistegina lessonii , Peneroplis pertusus , Neorotalia calcar , and Sorites orbiculus ), as well as smaller species ( Elphidium crispum , Glabratella patelliformis , and Discorbis turbo ). Biofacies III is found at a relatively muddy site that is rich in organic matter and heavy metals, particularly Cu and Zn. The foraminiferal assemblage is characterized by pollution-tolerant species, including Ammonia tepida , E. advenum , E. gerthi , Quinqueloculina eburnea , Q. bosciana , Haynesina germanica and Bolivina variabilis . The deleterious effects of pollution on the foraminiferal assemblage of biofacies III are clearly manifested by the highest incidences of test deformation.

Air pollution is reported as one of the most severe environmental problems in the Middle East and North Africa (MENA) region. Remotely sensed data from newly available TROPOMI - TROPOspheric Monitoring Instrument on board Sentinel-5 Precursor, shows an annual mean of high-resolution maps of selected air quality indicators (NO2, CO, O3, and UVAI) of the MENA countries for the first time. The correlation analysis among the aforementioned indicators show the coherency of the air pollutants in urban areas. Multi-year data from the Aerosol Robotic Network (AERONET) stations from nine MENA countries are utilized here to study the aerosol optical depth (AOD) and &Aring, ngstr&ouml, m exponent (AE) with other available observations. Additionally, a total of 65 different machine learning models of four categories, namely: linear regression, ensemble, decision tree, and deep neural network (DNN), were built from multiple data sources (MODIS, MISR, OMI, and MERRA-2) to predict the best usable AOD product as compared to AERONET data. DNN validates well against AERONET data and proves to be the best model to generate optimized aerosol products when the ground observations are insufficient. This approach can improve the knowledge of air pollutant variability and intensity in the MENA region for decision makers to operate proper mitigation strategies.

Atmospheric aerosol particles affect the formation of precipitation through influencing on microphysical properties of water and ice clouds. In early May of 2018, we observed the coincident of strong dust and rain events in the Nile Delta area. We also used Hybrid-Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, NMMB/BSC-dust model and NOAA-18 Cloud Height product to validate this same movement of dust and clouds that induced precipitation. In addition, Nino 3.4 index with historical rain and dust anomalous events during 1980–2017 were analyzed to reveal the relationship between these events and global climate system. The results revealed an obvious matching in both intensity and movement for both dust and precipitation events in early May 2018. Extreme precipitation anomalies during 1990–1999 occurred in company with positive Nino indices and less dust events.

Organochlorine contamination in the Mediterranean coastal environment of Egypt was assessed based on 26 surface sediments samples collected from several locations on the Egyptian coast, including harbors, coastal lakes, bays, and estuaries. The distribution and potential ecological risk of contaminants is described. Organochlorine compounds (OCs) were widely distributed in the coastal environment of Egypt. Concentrations of PCBs, DDTs, and chloropyrifos ranged from 0.29 to 377 ng g −1 dw, 0.07 to 81.5 ng g −1 dw, and below the detection limit (DL) to 288 ng g −1 dw, respectively. Other organochlorinated pesticides (OCP) studied were 1–2 orders of magnitude lower. OCP and PCBs had higher concentrations at Burullus Lake, Abu Qir Bay, Alexandria Eastern Harbor, and El Max Bay compared to other sites. OCP and PCB contamination is higher in the vicinity of possible input sources such as shipping, industrial activities and urban areas. PCB congener profiles indicated they were derived from more than one commercially available mixture. The ratios of commercial chlordane and heptachlor metabolites indicate historical usage; however, DDT and HCHs inputs at several locations appear to be from recent usage. The concentrations of PCBs and DDTs are similar to those observed in sediments from coastal areas of the Mediterranean Sea. Ecotoxicological risk from DDTs and PCBs is greatest in Abu Qir Bay, Alexandria Harbor, and El-Max Bay.

This investigation represents the first extensive study of the spatial distribution, sources, and potential effects of polycyclic aromatic hydrocarbons (PAHs) in sediments from Lake Manzala, the largest of Egypt's Mediterranean coastal lakes. The concentrations of PAHs (Σ39 components) ranged from 246 to 9910 ng g−1 dry wt., the highest values corresponding to urban hotspots with high anthropogenic input coming from wastewater discharges and combustion activities and decreasing offshore. The levels of PAHs were significantly lower compared to values reported in several coastal/estuarine areas (e.g., in Spain, Italy, USA, and Egypt) receiving substantial anthropogenic inputs from urban and industrial activities. Source ratios indicated that the PAHs were mainly from petrogenic sources in near-shore urban hotspots, with higher contributions of pyrolytic sources in coastal and offshore areas which are little influenced by human activities. Sediment quality guidelines (SQGs) showed that except at one station ...

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in surface and core sediment samples collected from Manzala Lake, the largest of the Egyptian coastal lakes. Total concentrations of OCPs and ∑7 PCBs (ICES) in sediments ranged from 0.63 to 31.31 ng/g and 0.26 to 31.27 ng/g, respectively. Geographical distribution indicates that levels of contaminants were significantly higher in areas which are mainly influenced by municipal discharge, indicating significant sources of these compounds in urbanised areas. The composition of DDT and its metabolites suggest old input of DDT. The levels of contaminants in Manzala Lake were similar or lower than those observed in comparable areas worldwide. The profiles of ∑OCPs and ∑PCBs in a core from a site heavily impacted by sewage discharge have highest concentrations in the surface core section indicating recent inputs. Assessment of ecotoxicological risk indicated that sediments in two sites were likely to pose potential biological adverse impact.

Organochlorine compounds (OCs) in surface and core sediments collected from Lake Maryut, Egypt, were examined to elucidate their distribution, ecological risk and historical trend. To our knowledge, this is the first study on residue levels of OCs in sediments from Lake Maryut. Concentrations of PCBs and DDTs were higher than other OCs, ranging from 3.06 to 388 and from 0.07 to 106 ng/g dry wt., respectively. The highest concentrations of OCs were found at stations near the discharge point of sewage and close to industrial areas. The distribution of DDT and its metabolites suggest no recent inputs into the lake environment. Contamination levels of sedimentary PCBs and DDTs, can be categorized moderate to high compared to other urbanized regions worldwide. Temporal trends in OCs levels were influenced by input pathways at two sites. Evaluation of ecotoxicological risks suggests that adverse biological effects are expected mainly in the main basin area.

In Egypt, the picture of threats to humans and the environment from the exposure to organic pollutants is still incomplete. Thus the objectives of this study were to assess the occurrence and distribution of polychlorinated biphenyls (PCBs), organochlorine pesticides, and chlorpyrifos in sediments and mussels of Abu Qir Bay and their risks for environment and human health.Twenty-three different compounds organochlorines were determined in 20 surfacial sediment and 10 mussel samples by gas chromatography-electron capture detector. A Screening Level Ecological Risk Assessment (SLERA) and a Human Health Risk Assessment (HHRA) were performed with the data.ΣDDT (DDT, DDE, DDD) (average concentration 27 µg/kg dw) dominated the detected organic pollutants in the sediments, followed by CHLs (chlordane, heptachlor, heptachloro epoxide), hexachlorocyclohexane, chlorpyrifos, endosulfane, dieldrine, Σ6 PCBs, aldrine, hexachlorobenzene, pentachlorobenzene, methoxychlor, and mirex. In general, concentrations of Σ6 PCBs in mussels were higher than their corresponding sediment concentrations reflecting their relatively high bioavailability and bioaccumulative potential. However, concentrations of the organochlorine pesticides in mussels were lower than their corresponding sediment samples. Nevertheless, the SLERA on the bay sediments revealed that adverse ecological effects to benthic species are expected to occur whereas the HHRA showed that adverse health effects are not expected to occur from the consumption of the mussels.With the help of a SLERA, it was possible to indicate which class of chlorinated organic compounds is of highest concern to assess and to improve the environmental quality of the bay. Monitoring of organochlorines and chlorpyrifos would be needed to control the future trend of pollution.

Sediment samples were collected from 30 different locations in Abu Qir Bay (Mediterranean Sea), East Alexandria, Egypt and analyzed for trace elements. The highest concentrations of most of the elements were observed in the nearshore stations in the vicinity of the major anthropogenic activities as industrial settlements, wastewater discharges, and agricultural drainage. In addition, mussel samples of Mactra corallina and Tapes decussata were collected corresponding to the sediment samples. Concentrations of As, Cd, Cr, Mn, and Zn in the mussel tissues were higher than concentrations in sediments, thus indicating their relatively high bioavailability. Sequential extraction procedure was performed on selected sediment samples. Significant correlations were observed between the concentrations of Cu, Mn, Pb, and Zn in the exchangeable fraction of the sediments and the corresponding tissues of M. corallina. The output of the risk assessment applied on the sediments revealed that adverse ecological effects to benthic species could occur and that a higher level of risk is expected from the exposure to Cd, Cr, Hg, and Zn. No adverse carcinogenic or non-carcinogenic human health effects are expected from the consumption of the two mussel species from Abu Qir Bay.

Concentrations of Al, As, Ba, Be, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, Sn, V and Zn in road dust particles at seven sites in the Delta region have been investigated using atomic absorption spectroscopy (AAS). Results showed that samples were highly contaminated with Cd, Pb, Sn and Zn and moderately contaminated with As, Se, Ba and Cu when compared to the average crustal background concentrations of metals. The output of the principle component analysis revealed that Al, Fe, Be and Mn were predominantly driven from natural sources and that all the other metals were anthropogenically driven from industrial activities (As, Ba, Cd, Cr, Cu, Se, and Sn) and traffic emissions (Pb, Ni and V). Results of the applied risk assessment indicated that the higher risk of occurrence of adverse non-carcinogenic health effects is associated with the exposure of children to Al, Fe, As, Cr, Pb and Zn via the ingestion pathway and that carcinogenic health effects are not expected to occur from the exposure to metals in the road dust of the Delta region. However, given the large uncertainties associated with the estimates of toxicity values and exposure factors, and the absence of site-specific biometric factors, these results should be regarded as a screening data. Further research should be undertaken before any definite conclusions regarding potential health effects are drawn.

Surface and core sediments from Lake Maryut, Egypt, one of the most polluted lakes in Egypt, were analyzed for polycyclic aromatic hydro- carbons (PAHs) using gas chromatography-mass spectrometry. This investigation represents the first extensive study of the distribution and sources of PAHs in sediments from Lake Maryut. The total PAHs concentrations (sum of 39 PAH compounds) in surface sediments varied greatly depending on the sampling location and ranged from 106 to 57,800 ng/g dry weight with a mean concentration of 6,950 ng/g. The most polluted areas are distributed in areas which are mainly influenced by municipal sewage and industrial effluent discharges, suggesting a direct influence of these sources on the pollutant distribution patterns. PAH concentrations were one to two orders of magnitude higher in comparison with those reported for riverine/ estuaries systems around the world. Molecular indices, such as pyrogenic index (PI), methylphenanthrenes to phenanthrene ratio, HMWPAH/LMWPAH, A-PAHs/P- PAHs, FL/FL+PY, BaP/BaP+C, IP/IP+BgP, and Per/ ∑(penta-aromatics) were calculated to evaluate differ- ent hydrocarbon origins and their relative importance. In general, sediments from the main basin and northwest basin of Lake Maryut showed the highest PAH concentrations with petrogenic signatures, indi- cating major sources of petrogenic PAHs in the city. On the other hand, lower levels of PAHs with a pyrogenic signature were widely recorded in areas that are distant from anthropogenic sources. At other locations, both petrogenic and pyrogenic inputs were significant. The concentrations of perylene relative to the penta-aromatic isomers are dominant especially in locations associated with terrestrial inputs and in the deepest core sediments, indicating diagenetic origin for the presence of perylene. Temporal trends of PAH concentrations in both cores sediments were influenced by input pathways and followed the economic development and the environmental policies of the Egyptian Government in the last 15 years. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (effects range median-effects range low) for evaluation probable toxic effects on organism. Results suggest an ecotoxicological risk for benthic organisms mainly in the main basin area, where high concentrations of PAHs were found in sediments influenced by anthropogenic activities.

To assess the status of polycyclic aromatic hydrocarbon (PAH) contamination in sediments of Hadhramout coastal area, Gulf of Aden, Yemen, 17 surface sediment samples were collected in March–April 2005 and analyzed for PAHs with 2–6 benzene rings by gas chromatography–mass spectrometry (GC-MS). The concentrations of PAHs in surface sediments were in the range of 2.2–604 ng g − 1 (average value: 82.4 ng g − 1 ). PAHs contamination is highest in proximity to harbour activities, near Al-Dhabah petroleum terminal and urban areas. Comparison of the concentration range with a worldwide survey of sedimentary PAH concentrations ranked PAH contamination in Hadhramout coastal sediments as low to moderate. Assessment of PAH sources in Hadhramout coastal sediments suggested that they originated largely from petrogenic sources. PAHs of pyrolytic origin were found in sediments from urbanized areas. Adverse effects on benthic communities are not expected at the levels of PAHs contamination observed from harbour and industrial areas.

The aliphatic and aromatic fractions of the extracts of ten street dust (SD) samples collected from eight cities covering a wide geographic area of Egypt were analyzed using gas chromatography with flame ionization detector (GC-FID) and GC–MS to compare their hydrocarbon distributions. To identify their sources, the extracts of the possible source materials were also analyzed. The impact of SDs on the marine environment was investigated in a marine sediment collected from the Western Harbor of Alexandria. The GC-FID profiles of the aliphatic fractions showed considerable differences in the n -alkane distribution that permits the classification of the SDs into five groups. This grouping reflects the environments of the cities in which they are collected. The carbon preference index and the unresolved complex mixture relative to the total resolved peaks values revealed that automobile exhaust is the main source of the hydrocarbons in these SDs with a significant contribution from terrestrial higher plant waxes to group 1 (Nile Delta cities). The sterane and hopane profiles supported this conclusion. The total polycyclic aromatic hydrocarbon (PAH) concentrations ranged from 27 to 379 ng/g (dry wt.) and showed clear differences between the SDs. The lowest and highest concentrations were found in samples from Shebeen and Port Said, respectively. The PAH distribution patterns and the ratio of the sum of combustion specific PAHs to total PAHs in samples from Alexandria, Port Said and Cairo were similar, implying similar sources. PAH ratios indicated a mixture of pyrogenic and petrogenic sources of PAHs in all samples where asphalt and automobile fuel exhaust were the major contributors of PAHs in Alexandria, Port Said, Cairo and Sharm El Sheikh cities. These ratios also indicated the predominance of diesel-operated vehicles to the PAHs signatures of Alexandria, Port Said and Cairo while gasoline emissions influence more strongly the PAH distributions in the SDs from Shebeen, Kafr El Sheikh and Sharkea. The PAH fingerprints excluded fresh oil and tire particles as major contributors. Both SDs and petrogenic sources significantly contributed to the hydrocarbon signature of the marine sediment from the Western Harbor of Alexandria.

Molecular geochemical properties of crude oils and surface petroleum seeps from the southern part of the Gulf of Suez were evaluated. The characterizations of individual aliphatic, aromatic, and biomarker compounds were based on gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) analyses. The results provided strong evidence for a close genetic association of these samples. The geochemical characteristics suggest an origin from Tertiary source rocks deposited in a normal marine environment that received continental runoff. The molecular signatures of the investigated samples were very similar to those of the Lower Miocene Rudeis Formation source rock in the southern Gulf of Suez. Further, biomarker fingerprints of the investigated oil seeps were compared with those of the Dead Sea asphalt, as well as the bitumen from some Egyptian mummies reported in the literature. The results demonstrate that oil seeps from the southern end of Gebel El Zeit were used by ancient Egyptians for embalming. © 2005 Wiley Periodicals, Inc.

Little data are available on the levels of polycyclic aromatic hydrocarbons (PAHs) in the sediments of the Mediterranean Sea Coast of Egypt in general and the Alexandria coastal zone in particular. It was therefore deemed necessary to set up a monitoring programme to determine the current concentrations of PAHs in bottom sediments, and to identify any area where high concentrations of these potential hazardous contaminants were present in the Western Harbour of Alexandria. The composition, distribution and the source of PAHs in surficial sediments of the harbour were investigated. To document the spatial PAH input, surficial sediment samples from 23 locations throughout the harbour were analysed. as]Results and Discussion The total PAH load determined in the surficial sediment samples ranged from 8 to 131150 ng g1 dry wt, generally with most of the samples having total concentrations of PAHs greater than 5000 ng g1 dry weight. The highest concentration of total PAHs was recorded in sediments of the inner harbour. Ratio values of specific compounds such as phenanthrene to anthracene, fluoranthrene to pyrene, methyl-phen-anthrene to phenanthrene, methyl-dibenzothiophenes to dibenzothiophenes, alkylated to non-alkylated and high molecular weight to low molecular weight PAH, were calculated to evaluate the possible source of PAH contamination in the harbour sediments. Two main sources of PAH in the study area have been found: pyrolytic and petrogenic. Interferences of rather petrogenic and pyrolytic PAH contaminations were noticed for most samples. The dominant sources of PAH appear to be the combustion processes through run-off, industrial and sewage discharges, and atmospheric input. The concentrations of PAHs were generally above levels expected to cause adverse biological effects. Information from this study and any other relevant studies should be useful in designing future strategies for environmental protection and management of the harbour.

In an attempt to examine the suitability of chemical fingerprinting methods in oil spill investigations, multiple parameters sensitive to both sources and degree of weathering were used to characterize spilled oil samples and to distinguish spilled hydrocarbons from sources unrelated to the spill in shoreline of the Gulf of Suez, Egypt. The characterizations of individual aliphatic and aromatic compounds were based on gas chromatography and gas chromatography/mass spectrometry analyses. The distribution of n-alkanes, polynuclear aromatic hydrocarbons (PAHs) and alkyl PAHs in the source oil and an oil slick collected 72 h after the spill were very similar. Major compositional changes observed in a weathered oiled sediment collected nine months after the spill from the shoreline at the spill location were consistent with previous studies. Molecular parameters of hopane and sterane biomarkers were very similar in the source oil, the spilled oil and the highly weathered oiled sediment. The similarity in biomarker compositions provided a strong evidence for a close genetic association of these samples. Ratios of C2-chrysenes/C2-phenanthrenes and C2-chrysenes/C2-dibenzothiophenes, the pregnane index (sum of the concentrations of C21 and C22 steranes over total concentration of steranes×100), and the tricyclic terpane index (sum of the concentrations of C19 and C30 tricyclic terpanes over total concentration of terpanes×100) clearly differentiated the refined oil products from crude oils. The composition of bilge oil indicated enrichment of late eluting steranes and terpanes and showed biomarker distributions similar to natural petroleum. The results further support that sterane and terpane biomarker analyses could differentiate oil samples of different sources even though they were sometimes indistinguishable in PAH and alkane compositions.

Seven crude oils representing the different petroleum-bearing basins in the Western Desert were characterized by a variety of biomarker and nonbiomarker parameters. For comparison, one crude oil from the Gulf of Suez region has also been studied. The oils have been analyzed for geochemical biomarkers using GC and GC-MS techniques. The results reveal significant differences within the oils that suggest five oil types. Type 1 oils from the Gulf of Suez show C 29 /C 30 17α(H) hopane ratio >1, high C 35 homohopane index, and the presence of considerable amounts of gammacerane indicating a marine saline carbonate or evaporite source rock and highly reducing (low Eh) conditions. Type 2 oils from Matruh basin and type 3 oils from Shushan basin are very similar and show relatively high Pr/Ph ratios, low sulfur and metal contents, paucity of C 30 steranes and the presence of high relative abundance of 17α(H) diahopane (C 30 *) suggesting that they probably originated from source rocks containing a significant proportion of higher plant material. Another related feature of these oils is the absence of 18α(H)-oleanane which suggests a source age older than Cretaceous. Type 4 oils from Abu-Elgharadig basin show terpane distribution dominated by C 24 tricyclic, absence of C 30 *-diahopane and medium diasterane/sterane ratios which reflect generation from marine siliciclastic source rocks. Type 5 oils from Alamein basin possess source biomarkers indicating a mixed contribution of terrestrial and marine sources. The presence of measurable amounts of oleanane in this type of oils suggests source rocks deposited in deltaic or near shore environment in Post-Cretaceous basin.

Five coal and shale core samples of the Middle Jurassic Safa Formation were taken from a newly drilled water well at the depth interval from 191 to 208 m, and have been investigated in this study. Detailed organic and inorganic geochemical analyses of the Safa Formation reveal no significant differences between the upper seams and the main seam. The extracts of the coal samples have an unusual n-alkane distribution; the GC traces are dominated by unusual compounds eluting between n-C19 and n-C21. These compounds are thought to be diterpanes, which suggest significant conifer contributions to the coals. Higher amounts of hopanes and higher carbon preference index (CPI) values (n-C22 to n-C30) show significant bacterial contributions in samples characterized by high values of tissue preservation index (TPI). The C31 αβ (22S/22S+22R) hopane and C29 ααα (20S/20S+20R) sterane ratios show least variation through the shale–coal sequence. Shale and coal samples from the upper and main seams are characterized by high relative abundance of 17β (H)-hopanes, which could be derived from non-microbial organisms such as ferns. The petrographic and geochemical evidences suggest that the Maghara coal was formed in a “wet forest–swamp” environment situated in a marine-influenced lower delta plain.

The acid fraction of crude oils and related source rocks of different stratigraphic units from the Gulf of Suez and Western Desert, Egypt were analyzed by GC and GC/MS. Normal alkanoic acids (n-C9−n-C30) were the dominant series (with the predominance of even-carbon numbers maximizing at n-C16, n-C18 or n-C22while iso- and anteiso- branched acids were minor constituents. All samples showed a preference of short chain acids (n-C10−n-C19 with respect to long chain acids (n-C20+) typical of marine oils and source rocks. The n-alkanoic acids distribution suggests a predominant algal and/or bacterial contribution. The presence of high relative abundance of mono and di-unsaturated carboxylic acids in a number of samples point to recent microbial activity. Distributions of n-alkanoic acids in the range (C12−C22) show striking similarities with the n-alkane distributions, indicating that both series may, at least in part, be diagenetically related by decarboxylation of the acids. Dehydroabietic acid has ...

In an attempt to investigate the suitability of a multibiological marker approach for defining the origin of petroleum pollution in marine systems, the aliphatic hydrocarbon compositions of tar ball samples collected from the beaches of a small island impacted by heavy tar loads were determined by gas chromatography and gas chromatography/mass spectrometry. The tar ball samples, as collected, were at low stages of biodegradation and had diverse physical appearance. The majority of the samples (as many as 7 of the 10) appeared to be heavy fuel oils—possibly Bunker C. The GC traces for the other three tar balls, however, indicated that they were crude oils probably from tanker ballast washings or other non-point sources like the oil entering from the adjacent North Mediterranean. The biomarkers of the sterane and hopane series in these samples, however, had remained unaffected by weathering, and their distributions revealed significant differences among the samples suggesting multiple sources of the tar balls. The tar ball samples could be genetically subdivided into four groups on the basis of their biomarker fingerprints. A marine carbonate or evaporite, hypersaline, anoxic depositional environment of the petroleum source rock for Type I residues could be inferred from the even-carbon-number predominance of n-alkanes, the high relative abundance of gammacerane and the predominance of C35 relative to C34 17α(H)-homohopanes. Higher plant contribution and a deltaic environment of source rock deposition could be concluded for Type II residues from the high concentrations of oleanane and diasteranes. On the other hand, Type III residues possessed geochemical characteristics consistent with a normal marine carbonate or evaporite source depositional environment under normal saline, reducing conditions. Finally, type IV residues had biomarker signatures intermediate between Types II and III.

The Cenomanian-Turonian transgression has been studied in a 220 m cored section using common source rock data, elemental data and conventional biomarker parameters. Differences in the type of organic matter found in these regressive and transgressive offshore marine sediments have been documented and assessed within a sequence stratigraphic framework. The interval of maximum flooding of the Cretaceous seaway shoreline is delineated by discontinuities in the total organic carbon content and Hydrogen Index. The overall transgressive event is also accompanied by (a) an increase in the concentrations of elements such as thorium, vanadium, potassium, barium, sodium...etc., (b) changes in the relative concentrations and the characteristics of the biomarker parameters and (c) changes in the characteristic features of the kerogen. All of these data are consistent with a simultaneous decrease in terrigenous organic matter and increase in marine algal input.

Crude oils from the Gulf of Suez and the North Western Desert of Egypt have been analyzed for geochemical biomarkers using GC and GC-MS techniques. The biomarker compositions of the crude oils have been used to differentiate crude oils of non-marine, normal marine and marine carbonate sources. The geochemical features of Zaafarana crude oil from the Gulf of Suez Basin indicate a marine carbonate depositional setting. One crude oil from Budran however, possesses geochemical characteristics consistent with an origin from source rock deposited in normal marine conditions. Bahar and Morgan show normal marine source rock deposition environment with terrigenous organic matter input. On the other hand, the crude oils from the North Western Desert have bulk and biomarker characteristics cosistent with non-marine depositional setting, with the exception of one oil sample which appears to have a mixed marine/terrestrial sources. The presence of oleanane in some of these oils suggests source rocks deposited...

The distribution patterns of methylhomologs of naphthalene and phenanthrene in five crude oils from the southern part of the Gulf of Suez, Egypt, have been examined by quantitative capillary gas chromatography (GC) and computerized gas chromatography/mass spectrometry (GC/MS). In general, the relative abundance of individual naphthalenes and phenanthrenes were not significantly different in the five oil samples. Correlation between the source rock deposition and the abundance of specific methylnaphthalene and melhylphenanthrene isomers are consistent with a marine type source materials for the analyzed Gulf of Suez oils. Maturity parameters based on methylnaphthalene and methylphenanthrene isomers were almost identical and are consistent with an advanced stage of maturity. Further, calculated vitrinite reflectance (Re) confirmed that the sediments have a range of maturity within the “oil window”.

Five crude oils from some producing wells in the southern part of the Gulf of Suez were characterized using a variety of organic geochemical parameters. The results reveal significant differences within the oils from the Gulf of Suez basin that suggest two oil types and one mixed type. Type 1 oils from Ras Fanar and East-Zeit fields show a high relative abundance of gammacerane indicating a marine saline-source depositional environment. Another related feature of these oils is the predominance of C 35 over C 34 17α( H )-homohopanes. Type 2 oils from Gama and Amal-9 wells show oleanane indices over 20%, indicating that they originated from an angiosperm-rich, Tertiary source rock. Type 3 oil from Amal-10 well has geochemical characteristics intermediate between those of types 1 and 2. This may reflect mixing of oils from the sources of both types 1 and 2. The geochemical characteristics of the oils vary sufficiently to suggest multiple sources. The type 1 oils possess geochemical characteristics consistent with Upper Cretaceous Brown Limestone or Lower Eocene Thebes Formation carbonate source rocks. Type 2 oils are very similar in geochemical character to the Lower Miocene Rudeis Formation source rocks.

Conventional organic geochemical and biomarker parameters are used together to provide information on source organic matter input, depositional environment, and the correlation between crude oils from different pay zones and geographical locations in Egypt. The method of biomarker characterization is based on the fractionation of crude oils by liquid chromatography into three main compound classes: saturated hydrocarbons, aromatics and N, S, O components. The identities of specific compounds and the carbon number distribution of n -alkanes and acyclic isoprenoids were determined by capillary column gas chromatography. On the basis of correlation plots between biomarker and nonbiomarker parameters, the oil samples are classified into three main groups. The first group includes oil samples from the central part of the Gulf of Suez (Balayem Land, Bakr, Gharib and July fields) and is typical of crude oils generated in a strongly reducing environment. The second group comprises oils generated from sediments deposited in suboxic conditions and includes oils from the south central and southern part of the Gulf (Ras Fanar, Shark El-Zeit, Amal 9, Amal 10 and Gamma) and Yidma crude from the Western Desert. The third group includes oil samples of the Western Desert from the Umbaraka, Khalda and Meleiha fields, which are typical of oils accumulated under oxic palaeoenvironmental conditions.

To assess the contamination of polycyclic aromatic hydrocarbons (PAHs) in the Mediterranean coastal environment of Egypt, 26 sediment samples from the coastline, harbours, estuaries and coastal lakes were collected and analyzed. The sediment PAH concentrations of thirty-nine 2–6 ring PAHs ranged from 13.5 to 22,600 ng/g. PAH profiles varied according to the nature of the site and its proximity to sources. Industrialized and urbanized region showed high level of PAHs contamination. In general, the contamination levels of PAHs were similar to those observed in contaminated and slightly contaminated sediments of the Mediterranean Sea. Molecular indices based on ratios of selected PAH concentrations were used to differentiate PAHs from pyrogenic and petrogenic and mixed origins. Good correlations were observed between the petrogenic index, MP/P, A-PAHs/P-PAHs and HMW/LMW. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (ERM–ERL) for evaluation of probable toxic effects on organism.

In the last three decades, the industrial and human activities in the coastal area of Saudi Arabia have increased dramatically and resulted in the continuous invasion of different types of pollutants including heavy metals. Seven sediment cores were collected from three major industrialized areas; Jeddah, Rabigh and Yanbu, along the coast of Saudi Arabia to determine the spatial and temporal distribution of metals and to assess the magnitude of pollution and their potential biological effects. Sediments were analyzed for texture, calcium carbonate contents, organic matter and metals (Al, Fe, Mn, Cd, Cr, Cu, Ni, Pb and Zn). Some metals like, Cr, Mn, Ni and Zn, were enriched in the upper 15 cm of core samples (recent deposition of sediments). Cadmium concentrations showed high fluctuations with depth and reverse pattern to that for Al, Fe and Mn which indicated land based sources of this element to the studied areas. Elevated concentrations of lead were recorded in the bottom layers of cores in Jeddah that indicated the most dramatic increase in usage of gasoline in early 1970s. The calculated contamination factors (CF's) were found in the following sequences: Cd > Pb > Ni > Cu > Zn > Cr > Mn for all studied areas. Results of Pollution Load Index (PLI) revealed that Jeddah is the most polluted area, followed by Rabigh while Yanbu is the least contaminated area. Except for Ni, the concentrations of most metals in the majority of sediment samples were believed to be safe for living organisms. As no data were available on the concentration of metals in core sediments in the coastal area of Saudi Arabia, the results of this study would serve as a baseline against which future anthropogenic effects can be assessed.

Four groups of rocks, having more than 0.5% of organic carbon are defined within the subsurface section of Rahmi area, Gulf of Suez. The deduced types of indigenous kerogen are: algal-amorphous, inertinite-woody, and herbaceous. The algal-amorphous kerogen of Rudeis/Nukhul Formations (Lower Miocene), Eocene and pre-Eocene rocks is recognized as being oil prone, that is having high capacity for generating oil. The application of hydrocarbon liquid window concept shows that the LOM values fall within the range from 8.6 to 10.8, and the thermal alteration index for the different units is not extended into oil generation window, where it ranges from immature (Kareem Formation-Lower Miocene), to moderately mature (Paleocene), to the beginning of the thermal phase of oil generation (Senonian). The vitrinite reflectance values indicate a low level of thermal maturity. The formational temperatures increase towards the depocentral part of the basin and eastwards to the present Gulf of Suez. The thermal maturity index increases towards ancient stratigraphic units. The study of organic richness, quality and maturity revealed that, where the Nukhul, Eocene and Senonian rocks are buried deeper in the study area, would have been excellent source rocks for oil.