Chemical Characterization and Source Identification of Beached Oil from Two Areas Along the North-Western Coast of Qatar

Over the years there have been several reports of oil spills affecting particularly the northern coast of Qatar. In most cases, the source of oil spills is not identified. The spilled oils are very resistant to degradation and can affect the coastal ecosystem over many years. Even today, after 24 years, some of the oil that was spilled during the 1991 Gulf War can be found in sand, close to the Al Zubahra UNESCO site. The Maersk Oil Research and Technology Center in Doha (MO-RTC) has established the Oil Fingerprint project in collaboration with the University of Qatar and the University of Copenhagen. One of the objectives of the collaboration is to identify the potential source and origin of oil spills based on their chemical composition. A total of 38 samples were collected. During the sampling campaign it was discovered that the coast was contaminated with highly weathered oil that could originate from the Gulf War era but also with more fresh oil that most likely originates from recent oil spills in the Arabian Gulf. We therefore collected polluted soil samples and contaminated sediments from two main areas along the beach in North-western Qatar. The samples were analysed using gas chromatography - mass spectrometry in selected ion monitoring mode (GC-MS/SIM) and the oil composition was characterized. The likely source of the beached oil was identified by a comparison of diagnostic source ratios by comparing petroleum hydrocarbon fingerprints of steranes and hopanes of the spills against an oil database. The initial chemical fingerprinting based on selected ion chromatograms (SICs) of steranes (m/z 217) and hopanes (m/z 191), were remarkable similar as were the C29-/C30-Hopane ratios between sampling sites. However, a more detailed pixel-based analysis showed significant differences between samples. The process also included an assessment of the physical and biological weathering effects on the oil spills. Petroleum biomarker patterns (steranes and hopanes) are identical for all 14 samples included in this pilot study. The only differences observed were in the relative concentration of LMW and HMW steranes. This could be due to real source oil differences, however, the general weathering patterns indicate that these differences are more likely due to extensive weathering of especially two samples (9-02, 3-02) but also 8-01 and 10-01 shows severe weathering effects. Analysis of alkyl-PAHs provided an overall evaporative weathering degree for the samples. Distinct differences in the isomer patterns were observed for 3- to 4-ring alkyl-PAHs and this cannot be immediately explained as biodegradation. The largest fraction of the samples seems to originate from the same source but other sources are clearly present. A more detailed analysis with normalization to Euclidean norms within six selected SICs revealed more source specific information. In conclusion, the results indicate at least 2-3 different sources on the basis of differences in PAH isomer patterns. This was confirmed by visual inspection of SICs of C1-C3 alkyl-substituted phenanthrene, dibenzothophene, chrysene and pyrene isomers. Apart from the finding that the spills originate from several sources, the evaporation profiles indicated that not all of the spills are crude oils but that some are also heavy fuels. This suggests ongoing bunker flush off the coast of Qatar. These findings are of importance in further bioremediation processes in which, different approaches should be investigated to achieve high efficiency strategies if removal of oil pollutants from AlZubaraa area.qscienc

Investigation of Spatiotemporal Variability of Microplastics in Qatar's Cstal Environment

There has been a tremendous proliferation in plastic production in the last five decades due to its low cost and versatile applications. Plastic debris dominates the marine litter globally and has been found in the most pristine environment including the abysmal region of the world ocean. Studies show that over 8 million tons of plastics are dumped in the ocean annually (Gregory, 2009). Plastics are persistent in the environment and take several decades to degrade especially in the ocean. Large plastic debris can heavily damage the coral reefs and may cause entanglement, choking, blockage of digestive tracts when ingested by turtles, whales, sharks etc, causing several thousand deaths annually among these organisms. Microplastics are tiny plastic particles that seldom originate from fragmentation of large plastic debris or are produced to serve some specific purposes. Microplastics pose greater threats as they can be mistaken for food by filter-feeders and planktivorous fish, and can also adsorb large quantities of recalcitrant organic pollutants (OPs). Impacts on marine biota may include endocrine disruption, carcinogenesis, and sexual disruption, etc. These impacts may not always be obvious but OPs surely affect marine biota once they enter the food web even at low concentrations (Mato et al., 2001) which biomagnify up the marine food web, hence, explains the need for their investigation. In this study, the spatial and temporal distribution of microplastics was investigated for the first time in Qatar; both in sediments and seawater. Eight beaches across Qatar and four sea surface stations were surveyed between the months of December 2014 and March 2015. The objectives of this study were: 1.To analyze the spatial and temporal variability of microplastics in seawater and sediments, in sea surface and intertidal sandy beach environments, respectively. 2.To characterize the isolated microplastics based on size, shape, colour, and type of polymer. 3.To describe macroplastics collected from beaches based on polymer type and quantify the concentration of OPs adsorbed on their surfaces. 4.?To investigate the rate of adsorption of OPs on virgin plastic pellets in a field experiment. A general overview of the followed methodologies is given in Appendix 1. In the first phase of this study, the spatial and temporal distribution of microplastics was investigated in seawater and sediments respectively. Four sea surface stations (Appendix 2) and eight beaches (Appendix 3) across Qatar were surveyed between the months of December 2014 and March 2015. Seawater was sampled respectively with a surface neuston net (300 ?m mesh size) towed off the side of the speedboat in undisturbed water for 5 minutes at 1.5 knots (Doyle et al., 2011). Next, collected materials in the cod were transferred into labeled, acid-treated insulated glass containers to prevent contamination. Concentrations of microplastics were given in square meters as sampling was done in two-dimensional air-sea interface. Physicochemical parameters (temperature, salinity, pH and dissolved oxygen) were measured in-situ and recorded at each sampling site. Additionally, eight coastal stations (Al Dhakhira, Ras-Laffan, The Pearl, Doha Bay, Al Ruwais, Dukhan, Umm Bab, and Mesaieed) were chosen on the basis of their accessibility and being evenly distributed along Qatar coastline. For each sampling, sediments from the top 2 cm were collected at the most recent high tidal mark on shore from a square area (0.5 0.5 m) along the shore line. Three replicate quadrats (5 meters apart) were sampled in each beach. The samples were homogenized and transferred into acid-treated glass containers to prevent contamination and transported to the laboratory for analyses. Microplastics (Appendix 4) were discovered in all samples and their abundance varied both in intertidal sandy beaches and sea surface. Two-factor ANOVA revealed that the spatial variability of microplastics in sea surface stations was statistically significant however, there was no observable temporal variability (Appendix 5). The average concentration of microplastics in all 8 beaches was not significantly different (Appendix 6). Chemical analysis revealed the occurrence of OPs with endocrine effects on all obtained macroplastics, and concentration of pollutants was consistent in all sites. Large piece-to-piece variations of contamination up to two orders of magnitude were discovered within sites (2 to 1,005 ng/g), although there was no significant difference in contaminant concentration among all sites for PCBs and PAHs respectively. Since plastic debris are hydrophobic and easily adsorb organic pollutants the second phase of this study was targeted at investigating the concentration of PCBs and PAHs adsorbed on macroplastics in situ. Field adsorption/desorption experiment was performed to investigate how pellets of different polymers and contaminated with POPs behave when placed in ambient seawater. Pellets were deployed and later retrieved at 48h, 96 h, 192 h, and 312 h respectively. The pellets were analyzed for PCBs and PAHs and undeployed pellets were also analyzed at time 0. Adsorbed PCBs and PAHs concentration showed a steady decrease with time, suggesting that contaminated pellets ending in the marine environment release their adsorbed contaminants in less contaminated seawaters revealing a complex OPs dynamic between plastics an seawater as a function of differential concentrations of pollutants and environmental conditions. This study is the first of its kind in Qatar and seemingly in the entire Arabian Gulf region. Marine pollution is a growing concern in Qatar coastal and offshore environment. Marine debris is of major concern due to the fact that plastic can take several decades to be fully degraded. Results from this study indicate that microplastics are ubiquitous in Qatar coastal environment and the fact that they are easily mistaken for food and ingested by zooplankton and smaller fishes makes them a serious threat to the marine food web. Hence, regular monitoring of the occurrence of microplastics and studying how they may affect the foodweb and potential contaminations of exploited (seafood) species are needed to give policy makers an insight of the sources of the debris and proffer suggestions on how to tackle the menace using a holistic approach.Qscienc

تقييم التناضح الأمامي كتقنية محتملة في تحلية مياه البحر

Abstract All researches and studies trending to seawater desalination technology, reverse osmosis or nanofiltration, but in this research I tended towards a new technique which is forward osmosis. Forward osmosis (FO) is one of the emerging membrane technologies which has gained renewed interest recently in desalination process, due to its advantages which is less consumption of energy because of low pressure used. The aim of this research makes an effort to investigate the efficiency performance of (FO) technology for extracting water from types of saline waters using as feed solution (FS) and using ammonium bicarbonate (NH4HCO3) as draw solution (DS). Two types of saline water were used: Aqueous solution and real water. The performance of tested membrane was measured in terms of flux rate and salt rejection under different operation conditions: feed solution (FS) concentration (2500-37000) mg/l, draw solution (DS) concentration (39,530-197,650) mg/l and applied pressure (0.5) bar. Experimental results showed that, increasing DS concentration reflect positive effects on both water flux and rejection rate because of increase of DS osmotic pressure. In other hand, increasing of the feed concentration reduced the water flux and rejection rate due to less difference in osmotic pressure. The results demonstrated the performance of FO for synthetic and real water in flux and salt, maximum water flux was 6.6 L/m2.h for synthetic seawater. In the other hand, for real seawater, results showed that maximum water flux was 4.7 L/m2.h, salt rejection was decreased by time from 97 to 94 %. In this study, heating process performed to removal and recovery ammonium bicarbonate from water. In conclusion, the results indicated that FO performance was encouraging and proved that FO system could be a powerful desalination unit for desalting different sources of saline waters at different concentration levels.جميع البحوث والدراسات تتجه إلى تحلية مياه البحر باستخدام تكنولوجيا التناضح العكسي أو أغشية النانو، ولكن في هذا البحث اتجهت نحو تقنية جديدة وهي التناضح الأمامي. التناضح الأمامي هي واحدة من التقنيات الناشئة والواعدة التي اكتسبت اهتماما متجددا مؤخرا في عملية تحلية مياه البحر لما لها من مزايا من أهمها قلة استهلاك للطاقة وذلك لقلة الضغط المستخدم. والهدف من هذا البحث هو تقييم أداء تقنية التناضح الأمامي باعتبارها تقنية محتملة في تحلية المياه (المياه الجوفية ومياه البحر). استخدمت نوعين من المياه المالحة: محلول مائي وماء حقيقي. وقد تم قياس الأداء للغشاء من حيث معدل التدفق واسترجاع الأملاح في ظل ظروف تشغيل مختلفة: تراكيز مياه مالحة (2500- 37000 ) ملغم / لتر، و بيكربونات الأمونيوم بتركيز من ( 39530- 197650) ملغم / لتر و الضغط (0.5) بار. أظهرت النتائج أن زيادة تركيز بيكربونات الأمونيوم تعكس آثارا إيجابية على كل من تدفق المياه و واسترجاع الأملاح وذلك بسبب زيادة الضغط الاسموزي. من جهة أخرى، زيادة تركيز المياه المالحة تؤدي إلى انخفاض تدفق المياه واسترجاع الأملاح بسبب قلة الفرق في الضغط الاسموزي. وكذلك أظهرت النتائج أداء الغشاء بالنسبة لمياه البحر الاصطناعية والحقيقية ، فكان أقصى تدفق المياه 6.6 لتر / لكل متر مربع في الساعة وذلك مع مياه البحر الاصطناعية. في المقابل، مع مياه البحر الحقيقية، أظهرت النتائج أن الحد الأقصى لتدفق المياه كانت 4.7 لتر / لكل متر مربع في الساعة ، وقد انخفضت نسبة الاسترجاع للأملاح ما بين 97 - 94٪. وتم في هذه الدراسة، استخدام عملية التسخين من أجل إزالة واستنقاذ بيكربونات الأمونيوم من المياه مرة أخرى. وفي الختام، أشارت النتائج إلى أن أداء التناضح الأمامي مشجع وأثبتت أن هذه التقنية يمكن أن تكون وحدة تحلية قوية لتحلية مصادر مختلفة من المياه المالحة في مستويات تركيز مختلفة

Approaches to achieve sustainable use and management of groundwater resources in Qatar

This paper reviews the hydro-geochemical characterization of Qatar's aquifer. In addition, it highlights the opportunities in the current groundwater management practices to achieve a sustainable groundwater use in Qatar such as assessing and monitoring the groundwater quantity and quality. In this review article, the Driver-Pressure-State-Impact-Response framework is used to analyze the water resource system in Qatar; begins by describing the causal chain from driving forces of impacts and finally state the responses. As the main driver is the intensive use of groundwater for agriculture irrigation, this causes high pressure on groundwater abstraction and deteriorate the state of the groundwater environment in term of quantity and quality, which has an impact on the food and water supply demands. Therefore, the final response highlights the need for the enhancing the rainfall infiltration to the aquifers, recharging the groundwater aquifers using treated sewage effluent or desalinated water development of groundwater treatment techniques, the use of efficient water irrigation practices, the reuse of treated wastewater for irrigation and the development of certain water-use tariff structures and awareness campaigns for farmers

Investigating the concomitant removal of hydrocarbons and heavy metals by highly adapted Bacillus and Pseudomonas strains

This study investigates the concomitant removal of hydrocarbons and heavy metals by highly adapted Bacillus and Pseudomonas strains. In regions characterized by harsh conditions such as Qatar, the weathering processes would affect the content, status, and distribution of these contaminants. It was shown in the weathered soil from Dukhan oil wastes dumpsite that 14 heavy metals exceeded the EPA limits. Moreover, it was demonstrated that soil organics did not affect the distribution of the metals in the soil. However, most of the heavy metals were strongly bonded to the residual and the iron-manganese oxide fractions. Eighteen bacterial strains isolated from highly weathered oily soils were able to grow with heavy metal concentrations up to 3 mM and above for some. Seven selected strains (4 Bacillus and 3 Pseudomonas) showed the ability to remove almost 60 to 70% of most of the heavy metals when used at 1 mM. Moreover, they removed up to 75% of the diesel range organics. These results are of interest for selecting bacterial strains, which can overcome the toxicity of hydrocarbons and heavy metals and remove them concomitantly

Solvent Extraction Of Total Petroleum Hydrocarbons From Contaminated Soils In Qatar

The increase of soil and water contamination, caused by oil leakages during transportation and storage of petroleum components, present serious threat to human health and the environment. Total petroleum hydrocarbons (TPH) is a commonly used gross parameter for quantifying environmental contamination that is originated by various petroleum hydrocarbons. The characterization of the petroleum contaminated soils will enable the selection of the most appropriate methods for bioremediation and rehabilitation of theses soils. Qatar's economic boom, based on the hydrocarbon industry, is putting a strain on other scarce resources. Due to the increase of industrial activates; several environmental issues arose in the recent years, putting at risk the natural and cultural resources of Qatar. Soil in Qatar is in general shallow sandy calcareous, overlying rocky bedrock. The available nutrition is poor with salty soil; they are adapted and tolerate different physical and chemical factors. In areas with long history of oil spells, it's important to conduct large-scale study in which oil weathering in the sediments is evaluated in terms of toxicity to the environment. Rehabilitation of lands should be further developed to preserve agricultural soils, and to prevent the spread of harmful molecules and their infiltration into the groundwater and in the food chain. Solvent extraction is a promising technology for degrading polluted soil. Consequently, several solvent has been researched; namely methanol, hexane, dichloromethane and acetone. The solvent mixture [hexane: dichloromethane (50:50)] efficiently extracts the polycyclic aromatic hydrocarbons (PAHs) compounds. The solvent extraction methods are useful to identify the composition of soil contamination which would assist in the treatment and remediation. Accelerated solvent extraction has been applied to extract of wide range of petroleum hydrocarbons, including aliphatic, polycyclic aromatic hydrocarbons (PAHs), phenols, and polychlorinated biphenyls (PCBs), while gas chromatography-mass spectrometry (GC-MS) is used to quantify the hydrocarbon compound in environmental samples. In this study, Total petroleum hydrocarbons was extracted and quantified in several samples collected from aged contaminated sites. The analytical results, indicated that the quantitative determination of the PAH was depended strongly on the sample preparation, and solvents The data collected in this baseline study should be further validated and incorporated with other studies that would guide the future remediation strategies.qscienc

The Influences of Produced Water Irrigation on Soil microbial succession and Turfgrass Grass Establishment in Qatar

The Influences of Produced Water Irrigation on Soil microbial succession and Turfgrass Grass Establishment in Qatar Sameera S. Shaikh, Mohammed H. Abu-Dieyeh*, Fatima A. Al Naemi, Talaat Ahmed, and Mohammad A. Alghouti Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University. *Corresponding author: [email protected] Abstract: Water scarcity around the world has necessitated the use of alternative water resources such as wastewaters, for irrigation purposes. Landscaped areas and turf grass systems provide varied environmental benefits including phytoremediation, erosion control and mitigation of heat island effects. They also provide safe, shady and cool places for athletic activities, exercise, and provide area for outdoor gatherings. Use of wastewater for turfgrasses has been conceptualized in the last decades and applied in various parts of the world. In this study, we attempted to use produced water (PW) to irrigate two turfgrass species, Cynodon dactylon and Paspalum sp., which are grown in local parks, green spaces and roadsides in Doha, Qatar. Effect of PW irrigation on established grasses, microbial succession, heavy metal accumulation and germination tests for weeds and turf grass seeds were investigated in greenhouse and field experiments. The two species of grass tested - C. dactylon and Paspalum sp. depicted different tolerance capacities towards PW. C. dactylon showed lower tolerance while Paspalum sp. depicted better tolerance capacity towards PW. C. dactylon grown from seeds under greenhouse conditions were not able to tolerate more than 30% concentration of PW. In comparison to tap water irrigated turfgrass, Paspalum sp. was found to accumulate higher concentrations of V and Pb in shoots and Cr, Ni and As in roots. For soil microbial succession studies, results from greenhouse experiment, using Cynodon dactylon turfgrass and after 14-weeks of produced water irrigation regimes, showed a significant reduction in bacterial colony forming units (CFU) at all produced water treatments compared with tap water irrigation. However, a significant increase through time in CFU occurred in all treatments. It was observed that PW irrigation caused changes in fungal species present in PW irrigated soil. The study of fungal succession in soil showed presence of certain species in 10%PW-30%PW treated soil that were absent in soil treated with tap water. Based on germination tests it was recommended that irrigation with PW be performed after turf grass establishment. Studies on weed germination suggested that PW could discourage growth of weeds - Amaranthus viridis and Launaea mucronata while promote growth of Chloris virgata. Based on the study conducted, it is suggested that PW could be used as alternative water resource to grow some species, but only after further research is conducted on the long term to assess any environmental toxicity.qscienc

Removal of Carbamazepine from Water by a Novel TiO 2

A novel TiO(2)–coconut shell powder (TCNSP) composite, prepared by the controlled sol-gel method with a subsequent heat treatment, was investigated as an innovative photocatalytic absorbent for the removal of carbamazepine (CBZ). CBZ is used worldwide as an antiepileptic drug, which has recently been recognized as an important organic pollutant increasingly found in wastewaters from urban areas and other aquatic environments. The granulation process was performed by using a semiautomated mass production line to produce sufficient quantities of TCNSP composites, possessing sufficient crush strength for commercialization. Physical properties of the TCNSP composite such as crystallinity, morphology, crush strength, and the Brunauer-Emmett-Teller (BET)–specific surface area were controlled by the mass ratio of titanium dioxide sol and coconut shell powder (CNSP). Calcination at 700°C produced anatase phase TiO(2) in the TCNSP composites with a BET high surface area of 454 m(2)/g. Anatase crystallite size of the TCNSP composite increased from 2.37 to 15.11 nm with increasing calcination temperature from 500°C to 800°C. Calcinated TCNSP composites had higher CBZ removal efficiency (98%) than pure TiO(2) (23%) and CNSP (34%) within a 40-min reaction time. Optimization of this innovative adsorption/photocatalytic process was obtained by a response surface methodology and a central composite design model, which indicated that this novel and sustainable technology was successful in removing CBZ from a solution