Co-Pyrolysis of Date Palm Waste and Salicornia Bigelovii: Insights for Bioenergy Development in Arid and Semi-Arid Regions.

Bioenergy is predicted to significantly contribute to the global energy needs of both developed and developing economies. Co-pyrolysis of halophytes offers a solution for a sustainable supply of feedstock in coastal and water-scarce regions. This novel research introduces an experimental investigation of co-pyrolysis of saline-tolerant flora (date palm waste and Salicornia bigelovii) to address sustainable waste management, bioenergy production, and efficient resource utilization in xeric regions. To examine the impact of the thermic condition on the pyrolysis products (bio-oil, biochar, and gas), the experiments have been conducted at three different temperatures (400, 500, and 600 °C). This pioneering study revealed that the co-feed bio-oil is acidic (pH 3.76-4.39) and has a high energy content (HHV 32.29-36.29 MJ/kg) that surpasses most woody biomass. The produced biochar was chemically stable, high in ash (40.09-47.62 wt %), high in fixed carbon (30.12-38.12 wt %), highly alkaline (pH 9.37-10.69), and low in HHV (16.30-17.2 MJ/kg). Increased pyrolysis temperature enhances biochar stability and fixed carbon, thus benefiting long-term carbon sequestration if applied in the soil. However, due to its high alkalinity, the application of this biochar in naturally alkaline sandy soils, such as in coastal deserts, requires careful monitoring. The hydrogen content in the gaseous phase significantly improves with rising temperature, reaching HHV = 24.12 MJ/kg at 600 °C, due to the enhanced ash catalytic effect. Overall, this study constitutes an important contribution to advancing bioenergy, sustainable feedstock, carbon capture, and waste management strategies in drought-prone areas.

A literature review addressing midwakh and e-cigarette use in the Gulf region.

A notable decrease in conventional cigarette smoking has been witnessed on a global scale. However, this decrease has been accompanied by an equally striking global increase in the consumption of alternative tobacco products (ATPs), namely e-cigarettes and midwakh in the Arabian Gulf region. A literature review was used to outline the chemical composition of these two ATPs and review their impacts on health. The study was conducted using databases like PubMed, Google Scholar, MDPI, and WorldCat. The literature search included terms such as "e-cigarettes," "midwakh," "dokha," "heath impacts," "psychological effects," "social influences," and "cigarette smoking" with emphasis on literature from the Arabian Gulf region. Data shows that midwakh contains markedly high levels of tar, nicotine, and various compounds of notable effects on the human body. Similarly, it was found that e-cigarettes contain non-negligible amounts of nicotine and other chemical compounds that may not have been extensively investigated. Alarming reports of system-specific effects brought about by midwakh, and e-cigarette consumption, have been reported, although further research is needed to deduce the mechanism. We also discussed some of the social and psychological factors leading to their consumption within this population. Hence, this review raises questions around the safety of these two types of ATPs and encourages comprehensive studies globally and regionally.

Applicability of Titanium-Based Catalysts in the Photocatalytic Degradation of 2,3,7,8-Tetrachlorodibenzofuran.

Polychlorinated dibenzofurans (PCDFs) are persistent toxic compounds that are ubiquitous in the environment. Nanocomposites of titanium(IV) oxide-vanadium(III) oxide (Ti3V2O7) and titanium(IV) oxide-silicon dioxide (Ti2Si7O30) were prepared and spectroscopically analyzed as potential decontaminants for dioxin-like materials. The analysis confirmed a homogeneous morphology with nanoscale particle size. The Ti-Si sample was found to have a high surface area compared to the Ti-V composite. Vanadium(III) oxide (V2O5) and silicon dioxide (SiO2) were chosen as materials for the formation of heterogeneous compounds with titanium(IV) oxide (TiO2) because they possess a suitable band alignment with TiO2, thus forming effective photocatalysts. This study evaluated the photodegradation of 2,3,7,8-tetrachlorodibenzo-furan (TCDF) in the presence of Ti-Si and Ti-V oxide composites, which was tested using high- (254 nm) and midenergy (302 nm) UV irradiation sources. While Ti-Si showed success in the photodegradation of 2,3,7,8-TCDF dissolved in a (1:1) methanol-tetrahydrofuran (MeOH-THF) solution, the Ti-V composite proved to be a powerful material in adsorbing TCDF with a high capacity immediately upon mixing. Ti-Si oxide was found to decompose TCDF under the two irradiation sources with 98-99% degradation occurring after 70 min. The use of 254 nm as an irradiation source in the presence of Ti-Si was 4.3 times faster than the analogue reaction irradiated without a catalyst. Byproducts of the degradation were evaluated using gas chromatography-mass spectrometry (GC-MS), resulting in a lower chlorinated congener and less toxicity, as the main degradation product.

Environmental assessment of oyster beds in the northern Arabian Gulf Coast of the United Arab Emirates.

The United Arab of Emirates (UAE) hosts valuable coastal and marine biodiversity, and oysters are one of the habitants of its marine ecosystem. Oysters play an essential role in the nearshore coasts where they work as an active filter. They filter nutrients, phytoplankton, sediments, heavy metals, and toxins out of the water, which improves the water quality. This is the first study that characterizes oyster bed habitats in the UAE by analyzing water quality parameters, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs)and heavy metals in water, sediments and oyster samples collected from five locations along the coasts of Sharjah, Ajman, and Umm al Quwain. Oyster bed areas supported a diverse assemblage of benthic life including oysters, scallops, pen shells, hard corals, and macroalgae. Mobile species in these habitats included groupers, emperors, snappers, sea snakes, among others. The phytoplankton assemblages were dominated by diatoms, dinoflagellates, and small cryptophytes. Harmful diatom Pseudonitzschia was found in all locations. No detectable concentrations of PAHs and OCPs were reported in this study, and water quality parameters were within the acceptable levels for the region. On the other hand, water quality index was reported marginal, mostly due to the presence of higher than acceptable concentrations of chromium and mercury in all sites studied. Bioconcentration factors concluded that oysters were able to bioconcentrate metals such as arsenic, cadmium, chromium, and zinc, when compared to water. No detectable concentrations of lead and mercury were reported in oysters, suggesting higher depuration rates for those metals.

Changing particle content of the modern desert dust storm: a climate × health problem.

Climate and land use changes together are altering the particle content of desert dust storms on regional and local scales. These storms now carry a wide variety of pollutants and pathogens arising from urbanization, industrialization, mass transportation, warfare, or aerosolized waste in locations worldwide where deserts are intertwined with built infrastructure, transportation centers, and high-density human habitation. Accordingly, the modern desert dust storm has an anthropogenic particle load which presumably sets it apart from pre-industrial dust storms. Evidence for how particle content for modern dust storms is changing over the Arabian Peninsula holds relevance because dust storms are now more frequent and more severe. Furthermore, the Arabian Peninsula has asthma rates which are the highest worldwide. How the modern desert dust storm contributes to asthma and human health is a nascent issue. Meanwhile, public health decisions can benefit from a climate × health framework for dust storms, as proposed here. An imperative is testing each dust storm's particle content type, and for this, we propose the A-B-C-X model. Sampling a dust storm for its particle content data and then archiving samples for future analyses is advised. A storm's particle content data, once combined with its atmospheric data, allows a particle's source, transport, and deposition to be determined. In closing, the modern desert dust storm's changing particle content has far-reaching consequences for public health, transboundary issues, and international climate dialog. SIGNIFICANCE : Locally and regionally sourced particle pollution is a growing problem in deserts worldwide. Proposed here is a climate × health framework for studying how dust storm particles, entrained from both natural and engineered systems, may be contributing to declining human respiratory health.

Oyster beds in the United Arab Emirates: Important fishing grounds in need of protection.

There is scarce information on the current importance of oyster beds as fishing grounds in the United Arab Emirates (UAE). This study aims to understand the socio-economic value of oyster bed fisheries through questionnaire-based surveys with fishers. Of 106 Emirati fishers interviewed, 67 % use oyster beds due to the proximity to shore, better catch quality, and species abundance. Oyster bed fisheries are recreational and commercial, with handline and fish traps the most common used gears. They provide food for local consumption and cash income. All respondents noticed a fish abundance and size decrease throughout the last decade. Fishers suggest establishing marine protected areas and updating fishing regulations to improve fishing stock status. During the Covid-19 pandemic, oyster fisheries increased, highlighting the value of these fishing grounds for food availability. These fisheries support the local economy and heritage, and urgently need management to ensure the protection of these often-overlooked habitats.

Factors influencing the prevalence of polycystic ovary syndrome (PCOS) in the United Arab Emirates.

Statistics indicate that at least 20-25% of women suffer from PCOS in the Gulf region. Despite its prevalence and negative implications on reproductive, metabolic, and physiological heath the exact cause of PCOS is unknown, in part due to the diversity of symptoms manifested by this disorder. In this review, we investigate causes of PCOS globally and draw on these studies, to determine the potential contributing factors for PCOS pathogenesis in the UAE population. The most frequently identified factors promoting PCOS pathogenesis that may be pertinent to this population include physiological factors such as insulin resistance, vitamin D deficiency, genetic factors, obesity, and anti-mullerian hormone (AMH) levels in the body as well as environmental factors such as air pollution, endocrine disrupting chemicals, and pesticide use. This evidence will help inform healthcare workers and government agencies to set up optimal guidelines for control and awareness of PCOS in the UAE.

Junk food: Polymer composition of macroplastic marine debris ingested by green and loggerhead sea turtles from the Gulf of Oman.

Pollution of the marine environment by plastic marine debris has become one of the most pervasive threats impacting marine environments. In this study, for the first time, we evaluate the polymer types of the plastic marine debris ingested by 49 green and 14 loggerhead sea turtle strandings in the Gulf of Oman. Plastic marine debris was ingested by 73.5% of green and 42.9% of loggerhead sea turtles in this study. Overall, evidence suggested that green sea turtles from the Gulf of Oman coast of the United Arab Emirates ingested high levels of plastic marine debris, predominantly Polypropylene (PP) & Polyethylene (PE), followed by Nylon, PP-PE mixture, Polystyrene (PS), Poly vinyl chloride (PVC) and Ethylene vinyl acetate (EVA), respectively. Loggerhead sea turtles also ingested high levels of plastic marine debris, which also predominantly consisted of PP & PE, followed by PP-PE mixture, Nylon and PS. While recent studies were directed into polymer characterization of micro-plastics in aquatic life, our study focuses on macro-plastics which impose significantly greater risks.

Oil spill causes mass mortality of sea snakes in the Gulf of Oman.

Oil spills in the marine environment inflict significant impacts on a wide diversity of marine fauna. Despite the abundance of literature describing these impacts on numerous species, no studies describe the impacts on sea snakes. In this study we report, for the first time, details of an oil spill which caused mass mortality of sea snakes. In this study, 39 sea snake mortalities from the Gulf of Oman, in particular, the coast of Kalba, Sharjah, UAE, were examined. The investigated sea snakes belong to four different species (Hydrophis platurus, H. lapemoides, H. spiralis and H. ornatus). The majority (84.6%) of sea snakes were observed to have oil covering 75-100% of their bodies. The majority (91.4%) of sea snakes were also observed with oil covering their snouts and eyes. A large proportion (25.8, 41.4 and 34.5%) of sea snakes were observed with oil in their mouth, esophagus and stomach.

Midwakh: Assessment of Levels of Carcinogenic Polycyclic Aromatic Hydrocarbons and Nicotine in Dokha Tobacco Smoke.

Midwakh, which originated in the Middle East, has started to spread globally with different brands commercialized online and in local stores across Europe and the USA. Dokha is the tobacco used in midwakh. To this day, risk of midwakh smoking is poorly understood. Three different types of dokha were evaluated in this study, classified as cold, medium, and hot using gas chromatography-mass spectrometry (GC-MS). The concentrations of nicotine and polycyclic aromatic hydrocarbons (PAHs) in raw and smoked dokha samples were measured, and the results were compared to data in the literature on different types of tobacco products. PAH concentrations were used to estimate the toxic equivalency quotient, daily exposures, incremental lifetime cancer risk, and hazard quotient. The level of nicotine in raw dokha exceeded by far the levels reported in cigarettes, cigar, waterpipe, and chewing tobacco. Although only a portion of the nicotine is released into the smoke, the amount of nicotine in dokha smoke exceeded those reported for cigarettes. Two PAHs were found in raw dokha at trace amounts and 12 PAHs were detected in dokha smoke in amounts that exceeded those reported for cigarette smoke. The PAHs distribution showed a specific pattern in the smoke and a higher risk factor than that obtained for cigarettes and other tobacco products. Dokha products present a potential higher risk and immediate action should be taken to avoid its global consumption.

Junk food: A preliminary analysis of ingested marine debris by hawksbill Eretmochelys imbricata and olive ridley Lepidochelys olivacea sea turtles (Testudines: Cheloniidae) from the eastern coast of the United Arab Emirates.

For the first time, the qualitative and quantitative characteristics of marine debris ingested by six hawksbill (Eretmochelys imbricata) and seven olive ridley (Lepidochelys olivacea) sea turtles from the Gulf of Oman coast of the United Arab Emirates were investigated. The numeric and gravimetric proportions of ingested marine debris obtained from the esophagus, stomach and intestines were quantified following categories of presumed sources, Marine Strategy Framework Directive (MSFD), rigidity, color and plastic polymer types. Marine debris was observed in 28.6% of olive ridley (x̅: 2.00 items; 4.83 g) and 83.3% of hawksbill specimens (x̅: 6.00 ± 2.32 items; 0.32 ± 0.24 g). Overall, the results of this preliminary study suggest that hawksbill sea turtles were ingesting marine debris at higher frequencies and that plastics were observed to be the most predominant debris ingested. However, non-plastic rubbish, particularly metallic fishing gear (fish hooks and fish traps), were observed to present lethal hazards for both species.

Analysis of polychlorinated biphenyls, polycyclic aromatic hydrocarbons and organochlorine pesticides in the tissues of green sea turtles, Chelonia mydas, (Linnaeus, 1758) from the eastern coast of the United Arab Emirates.

The level of contamination of selected priority pollutants consisting of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) were investigated from the tissues of stranded green sea turtles, Chelonia mydas, from the Gulf of Oman coast of the United Arab Emirates. Tissue samples - muscle and liver - were collected from 22 stranded green sea turtles from the coasts of Kalba and Khorfakkan from 2016 to 2018. Overall, we detected persistent organic pollutants (POPs) in 77% of the turtles. PAH's were the most frequently detected followed by high concentrations of OCP's (71% and 25% of the turtles, respectively). PCB's were not detected in any samples. Factors such as specimen size, mass of debris ingested and toxin hydrophobicity were not important factors affecting the concentrations of these compounds.

Potential causes of asthma in the United Arab Emirates: drawing insights from the Arabian Gulf.

There is considerable concern on the rise in the incidence of asthma worldwide with statistics in the United Arab Emirates (UAE) indicating that at least 13% of schoolchildren, particularly of Emirati descent, suffer from asthma. With its high rates of hospital admissions, negative socioeconomic impact and significant morbidity, this is a disease that requires optimal guidelines for control and awareness. In this article, we review the current knowledge of asthma in the UAE and draw on studies, especially from the surrounding region, to identify its contributing factors within this population. The most frequently identified agents pertinent to the UAE include outdoor and indoor environmental causes exacerbated by the country's rapid urbanization, genetic factors aided in transmission by consanguineous marriage, the patient's socioeconomic status and a rise in vitamin D deficiencies. This evidence aims to inform healthcare professionals and governmental agencies in order to best create guidelines for controlling the burden of this debilitating disease.

Chemical and biological assessment of sediments and water of Khalid Khor, Sharjah, United Arab Emirates.

Water and sediments were collected on March 2013 and April 2014 from Khalid Khor creek area in United Arab Emirates to assess their quality parameters. The pH and alkalinity of the water samples were measured and their values were similar to those of shallow saltwater ecosystems. In addition, elemental analyses and organic compounds were done using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) and Gas Chromatography-Mass Spectroscopy (GC-MS), respectively. The concentration of heavy and trace metals in the water samples were within the acceptable limits except for lead which showed high values, while the concentrations of metals in the sediment samples were relatively high and ranged from 6517 to 13,768mg/kg. GC-MS analysis showed the presence of polyaromatic heterocyclic (PAHs) compounds in sediments near the shipping area and in amounts classified as highly carcinogenic; however, no polychlorinated biphenyls (PCB) were identified. Moreover, fecal bacterial contamination in water was detected in concentrations that range between 300 and 10,140 organisms/100mL.

Trace metals, PAHs, and PCBs in sediments from the Jobos Bay area in Puerto Rico.

This study provides baseline information on the extent of contamination in sediments of the Jobos Bay estuary and surrounding areas in Puerto Rico. Sediments from Jobos Bay area (n=14) had higher overall average concentrations than those from La Parguera area (n=5, used as reference site), in microg/g dw, for As (17 vs 9), Cu (29 vs 14), Pb (11 vs 4), and Zn (64 vs 28); and in %, for Fe (2.6 vs 0.6). Sediments (n=8) screened for PAHs and PCBs exhibited total concentrations (ng/g dw) that ranged from 40.4 to 1912, and from not detected to 11.21, respectively. The quality of sediments of Jobos Bay could be classified as low to moderate pollution. The proximity to anthropogenic sources of contamination warrants a monitoring program for inorganic and organic pollutants in Jobos Bay area for an effective coastal management program of this tropical ecosystem.

PCB and PBDE levels in wild common carp (Cyprinus carpio) from eastern Lake Erie.

Male common carp (Cyprinus carpio) from eastern Lake Erie, which is greatly effected by urbanization, agriculture, and industry, were analyzed for PCB and PBDE concentrations in plasma, muscle, and liver to evaluate exposure to these chemicals through habitat interactions. Additional male carp from two nearby relatively clean lakes (Bear Lake and Hemlock Lake, NY) were also sampled as controls. While PCBs were detected in muscle, liver, and plasma of Lake Erie carp, the largest concentrations were found in muscle, which also had the most number of congeners. The dominant congeners were PCB 138 and PCB 153. Concentrations of PCB 153 in the muscle were correlated with fish length, total weight, and age. Therefore, larger (and generally older) carp had the highest concentrations of PCB 153. In contrast, PBDEs were found only in muscle with the predominant congener being PBDE 47. The total PCB concentrations in muscle of male carp from eastern Lake Erie (ranging from nd to 15,000 ng g(-1) lipid) were 100-fold higher than the total PBDE observed (1.5-100 ng g(-1) lipid), indicating a higher level of contamination of PCBs in Lake Erie. The high PCB levels in carp points to PCB resistance to metabolic degradation.

Toxicity comparison of chlorinated and brominated dibenzo-p-dioxins and dibenzofurans in industrial source samples by HRGC/HRMS and enzyme immunoassay.

Limited information is available on the applicability of polychlorinated dibenzo-p-dioxin/furan (PCDD/F) toxicity assays to their brominated counterparts: polybrominated dibenzo-p-dioxins/furans (PBDDs/Fs). We estimated the toxicity of mixtures of chlorinated, brominated, and mixed bromochloro-dioxins and -furan (PBCDDs/Fs) laboratory standards using a chemically-activated luciferase gene expression cell bioassay (CALUX). The relative effects potency (REP) values obtained were comparable to the World Health Organization (WHO) toxic equivalency factors (TEFs) and in agreement with the concept of additive congener toxicity of mixtures of dioxins and furans. Enzyme immunoassay (EIA)-based toxic equivalents (TEQs), however, showed overestimation for PCDDs/Fs (0-4 orders of magnitudes higher) and underestimation for PBDDs/Fs (0-1 orders of magnitude lower) when compared to high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS)-based TEQ calculation (using WHO TEFs) in samples from an industrial source line. No correlation was found between the EIA and the HRGC/HRMS data, which could be attributed to differences in homologue-specific cross-reactivity responses, sample matrix type, and presence of other compounds competing for antibody binding in the immunoassay.

Determination of relative assay response factors for toxic chlorinated and brominated dioxins/furans using an enzyme immunoassay (EIA) and a chemically-activated luciferase gene expression cell bioassay (CALUX).

Determination of toxic activity requires knowledge of both the concentration and toxicity to evaluate the risk for adverse human health and environmental effects. A chemically-activated luciferase gene expression cell bioassay system (CALUX) and an antibody-based method enzyme immunoassay (EIA) were used to detect the dioxin-like response of several polybrominated, polychlorinated, and polybrominated/chlorinated dibenzo-p-dioxins/furans (PBDDs/Fs, PCDDs/Fs, and PBCDDs/Fs, respectively). It has been suggested that the biological activity of the brominated and mixed bromo/chloro compounds is similar to their chlorinated analogues (measured by binding to the Ah receptor). PBDD/F, PCDD/F, and PBCDD/F laboratory standards exhibited biological activity ranging over three orders of magnitude. The highest relative potency (REP) values from CALUX analysis, when compared to 2,3,7,8-TCDD, were 2,3,7,8-TBDD at 0.99 (+/-0.07), 1,2,3,7,8-PeCDD at 0.69, and 2-Br-3,7,8-TriCDD at 0.72 (+/-0.02). Cross-reactivities were calculated using EIA for several PBDDs/Fs and PBCDDs. The highest percent cross-reactivity was found for 2,3,7,8-TBDD at 138 (+/-34%), and 2,3,7-TriBDD at 84 (+/-36%).

Determination of potential sources of PCBs and PBDEs in sediments of the Niagara River.

Sediments from Niagara River, an important waterway connecting two of the Great Lakes (Lake Erie to Lake Ontario), were analyzed for 14 congeners of polychlorinated biphenyls (PCBs) and 9 congeners of polybrominated diphenyl ethers (PBDEs) using accelerated solvent extraction and gas chromatography/mass spectrometry. Total concentrations of PCBs ranged from 1.7 to 124.6 ng/g were PCBs 138 and 153 were found in all samples. All sites but one showed PBDE in sediments with total concentrations as high as 148 ng/g, suggesting that PBDE is becoming an important class of POP. A land-use and coverage map was used to trace potential localized sources of PCB and PBDE contamination. Results indicate that the highest levels of PCBs and PBDEs were found in sediments collected from areas closest to the discharge locations of municipal wastewater treatment plants (WWTP) and local industries. This is the first study that suggests the importance of WWTP discharges as a potential source of PBDE contamination in the Great Lakes.