Prevalence of microplastics in the marine waters of Qatar

The issue of plastic pollution in the marine environment is of increasing global concern. As plastics typically have an intrinsic durability, water insolubility and slow degradation rates, debris has now become both ubiquitous and persistent in the marine environment. Overtime, plastic ultimately result in the generation of microplastics via photolytic, thermal and biological degradation processes. Although the potential threat of microplastics on marine ecosystems is well recognized, there is no baseline data available for the Arabian Gulf. The Environmental Science Center of Qatar University has now documented the first evidence for the prevalence of microplastics within the Arabian Gulf, specifically in the marine waters of Qatar Exclusive Economic Zone (EEZ). Qatar has an arid climate and is situated midway along the western coast of the semi-enclosed Arabian Gulf. Qatar's coastline is particularly susceptible to marine debris due to the county's rapid urbanization and economic development. Surface seawater samples were collected from 12 stations during May 2015 research cruise of the RV Janan. An optimized and validated protocol was developed for the extraction of microplastics from plankton-rich samples without loss of microplastics present. Plankton present in seawater samples may readily mask the identification of microplastics and lead to an underestimation of the quantity of microplastics present. The protocol involved sample digestion using solutions of 1M NaOH, 10M NaOH, and 16M HNO3 in conjunction at different temperatures. Twenty mL of each solution was spiked with known quantities of reference polymer pellets, of varying diameters (63 μm to 4.70 mm) and used to digest the plankton biomass. The use of 1M NaOH proved to be a more efficient digestion treatment than 10M NaOH and 16M HNO3 solutions. Although 10M NaOH, and 16M HNO3 have been proven effective to mineralize plankton biomass, these solutions also resulted in some structural damage and discoloration of reference polymers with a low pH tolerance: polyvinyl alcohol, polyvinyl chloride, polystyrene, polyethylene, and nylon. After extraction, the microplastics were characterized using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. In total 30 microplastics were isolated from the mineralized samples, with an average concentration of 0.71 particles m− 3 (range 0–3 particles m− 3). Nine out of 30 were identified as polypropylene, with the majority either granular, sizes ranging from 125 μm to 1.82 mm, or fibrous, sizes from 150 μm to 15.98 mm. Microplastics were more prevalent in areas where nearby anthropogenic activities, including oil-rig installations and shipping operations, are present.qscienc

Ecological indicators and source diagnostic ratios of aliphatic and polyaromatic hydrocarbons in marine sediments of Qatar

The marine ecosystems surrounding oil and gas production sites are particularly vulnerable to ecological harm that may be affected by its operations. In this study, we examined the composition, contaminant sources, and the potential ecological risk of aliphatic hydrocarbons (AH) and polyaromatic hydrocarbons (PAH) in the marine sediments along the western coast of Qatar. The ΣAHs concentration ranged from <0.10 to 246 ng·g-1 (site SD2) while the ΣPAH concentration ranged from <0.10 to 44 ng·g-1 (site SD10). Pollution concentration profile was site specific where AH and PAH concentrations were relatively higher within close proximity to the oil and gas production. TOC appeared to be positively correlated with PAH and therefore a good indicator for PAH but not for AH. Low molecular weight even-carbon numbered alkanes (n-C10-18) were more abundant than the higher molecular weight (n-C20-34) AHs. The Ʃ16PAHs compositional analysis mean concentrations were composed of 2-ring (6%), 3-ring (18%), 4-ring (48%), 5-ring (28%), and 6-ring (0.14%), respectively. Fluoranthene obtained the highest concentration of 11 ng·g-1 (site SD10). Diagnostic ratios and hydrocarbon parameters suggested mixed sources of petrogenic, pyrolytic, and biomass except for vehicular traffic. The overall results for AH and PAH indicated low pollution based on pollution criteria and were below the threshold limit set by the National Oceanic and Atmospheric Administration (NOAA) and the Canadian Sediment Quality Guidelines (CSQG). This suggests low probability of a negative toxic effect caused by these contaminants however, continuous long term-monitoring is needed to ensure these pollutants do not exceed the current levels

Prevalence of microplastics in the marine waters of Qatar

Microplastics are firmly recognized as a ubiquitous and growing threat to marine biota and their associated marine habitats worldwide. The evidence of the prevalence of microplastics was documented for the first time in the marine waters of Qatar's Exclusive Economic Zone (EEZ). An optimized and validated protocol was developed for the extraction of microplastics from plankton-rich seawater samples without loss of microplastic debris present and characterized using Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy. In total 30 microplastic polymers have been identified with an average concentration of 0.71 particles m− 3 (range 0–3 particles m− 3). Polypropylene, low density polyethylene, polyethylene, polystyrene, polyamide, polymethyl methacrylate, cellophane, and acrylonitrile butadiene styrene polymers were characterized with majority of the microplastics either granular shape, sizes ranging from 125 μm to 1.82 mm or fibrous with sizes from 150 μm to 15.98 mm. The microplastics are evident in areas where nearby anthropogenic activities, including oil-rig installations and shipping operations are present.Scopu

Field and laboratory investigation of tarmat deposits found on Ras Rakan Island and northern beaches of Qatar

© 2018 Elsevier B.V. Beaches of Ras Rakan Island, located off the northern tip of Qatar, are extensively contaminated by highly weathered tarmat deposits. The focus of this study is to determine the possible source of the contamination and complete a preliminary assessment of its potential environmental impacts. The field data collected at this site indicated that the tarmat residues contained highly weathered, black, asphalt-like material and the contamination problem was widespread. Based on these field observations, the following two hypotheses were formulated: (1) the tarmats must have formed from the residual oil deposited by a relatively large, regional-scale oil spill event, and (2) the oil spill must be relatively old. As part of this study, we collected tarmat residues from several beaches located along the northern region of Qatar Peninsula. We found the hopane fingerprints of these tarmat samples were identical to the fingerprints of the samples collected from Ras Rakan Island. These results together with our physical field observational data validated our hypothesis that the oil spill should have been a regional-scale event. Furthermore, we compared the measured hopane fingerprints of our field samples with fingerprints of reference crude oils from Qatar, Saudi Arabia, and Basrah (located close to Kuwait border), and with the literature-derived hopane fingerprints of Kuwaiti and Iranian crude oils. This analysis indicated that the hopane fingerprints of the tarmat samples closely matched the Kuwaiti and Basrah crude oil fingerprints. Since there were no known oil spills of Basrah crude in this region, the highly weathered, asphalt-looking tarmats should have most likely formed from the 1991 Gulf War oil spill, an old oil spill. The concentrations of parent and alkylated PAHs in the tarmat samples were also quantified to provide a preliminary assessment of potential environmental risks posed by these tarmats to Qatar's coastal ecosystem

Baseline concentrations and distributions of Polycyclic Aromatic Hydrocarbons in surface sediments from the Qatar marine environment

Coastal sediments in marine waters of Qatar have the potential of being contaminated by Polycyclic Aromatic Hydrocarbons (PAHs) due to extensive petroleum exploration and transportation activities within Qatar's Marine Exclusive Economic Zone. In this study, the concentration and distribution of sixteen PAHs classed as USEPA priority pollutants were measured in sediments from the eastern Qatari coast. PAHs were recovered from sediments via accelerated solvent extraction and then analyzed using Gas Chromatography–Mass Spectrometry. Total concentrations of the PAHs were in the range of 3.15–14.35 μg/kg, and the spatial distribution of PAHs is evaluated in the context of sediment total organic content, depth and the grain size together with and the proximity of petroleum exploration and transportation activities. The data show that the concentrations of PAHs within the study area were in the low-range, suggesting a low risk to marine organisms and limited transfer of PAHs into the food web

Bioethanol Production from Waste and Nonsalable Date Palm (<i>Phoenix dactylifera</i> L.) Fruits: Potentials and Challenges

Balancing the needs of current and future generations stimulates investment for sustainable development such as converting waste biomass into biorenewables. Sugar-based ethanol production is a well-investigated and established process, and researchers are now focusing on the transformation of cellulosic biomass to sugar and the application of non-conventional methods for ethanol production. The State of Qatar generates date palm fruit waste of approximately 4505 tons annually, excluding ornamental palms and palms outside the farms that bear nonmarketable date fruits. Date fruit molasses contains fermentable sugars, representing 75% of the total fruit mass, which can offer a good source for bioethanol production through anaerobic fermentation and distillation. On this basis, the valorization of waste date fruits can be an effective zero-waste strategy via biotransformation into bio-renewable materials, hence, contributing to the achievement of sustainable development goals. This paper reviews the potentials and challenges for the utilization of waste date fruits as a bioethanol source and assesses the abundance of waste date fruits as raw material for the conventional bioethanol conversion process. The review also identified conventional and nonconventional processes for bioethanol production and their applicability to Qatar. Finally, this confirmed ample demand for bioethanol ranging from fuel and industrial chemicals to pharmaceutical alcohol