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Detection of R-plasmids in Salmonella isolated from clams and marine waters of Kuwait.
1985
Chugh T.D. | Kadri M.H.
Health risks associated with the polycyclic aromatic hydrocarbons in indoor dust collected from houses in Kuwait Полный текст
2020
Al-Harbi, Meshari | Alhajri, Ibrahim | Whalen, Joann K.
Polycyclic aromatic hydrocarbons (PAHs) are a byproduct of combustion processes. They are common pollutants in oil-producing countries because fossil fuel processing generates PAHs that associate with dust. Airborne particles containing PAHs are transported into houses during dust storms, which are common in the arid oil-producing countries, and consequently the children and adults in the household are exposed to PAHs in indoor house dust. The goal of this study was to present a systematic survey of PAHs in indoor house dust in Kuwait. The PAHs concentrations and composition of indoor house dust was determined, along with their probable source and the potential carcinogenic risks. Total PAHs concentrations (ƩPAH) were, on average (±standard deviation) 1112 ± 347 μg/kg and ranged from 450 to 2242 μg/kg. Heavier congeners (4–6 ring PAHs) represented 61% of the ƩPAH. Petroleum combustion and traffic emissions were the major source of PAHs, based on the isomeric ratios of PAHs in indoor house dust. The incremental lifetime cancer risks (ILCRs) of exposure to PAHs in indoor house dust was 2.23 × 10⁻³ (95% CI: 1.99 × 10⁻³ – 2.48 × 10⁻³) for children and 2.15 × 10⁻³ (95% CI: 1.94 × 10⁻³ – 2.37 × 10⁻³) for adults, exceeding the US EPA safe limit of 1 × 10⁻⁶. Therefore, exposure to PAHs present in indoor house dust increases the cancer risk for children and adults in Kuwait.
Показать больше [+] Меньше [-]The impact of COVID-19 lockdowns on surface urban heat island changes and air-quality improvements across 21 major cities in the Middle East Полный текст
2021
El Kenawy, Ahmed M. | Lopez-Moreno, Juan I. | McCabe, Matthew F. | Domínguez-Castro, Fernando | Peña-Angulo, Dhais | Gaber, Islam M. | Alqasemi, Abduldaem S. | Al Kindi, Khalifa M. | Al-Awadhi, Talal | Hereher, Mohammed E. | Robaa, Sayed M. | Al Nasiri, Noura | Vicente-Serrano, Sergio M.
This study investigates changes in air quality conditions during the restricted COVID-19 lockdown period in 2020 across 21 metropolitan areas in the Middle East and how these relate to surface urban heat island (SUHI) characteristics. Based on satellite observations of atmospheric gases from Sentinel-5, results indicate significant reductions in the levels of atmospheric pollutants, particularly nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO). Air quality improved significantly during the middle phases of the lockdown (April and May), especially in small metropolitan cities like Amman, Beirut, and Jeddah, while it was less significant in “mega” cities like Cairo, Tehran, and Istanbul. For example, the concentrations of NO₂ in Amman, Beirut, and Jeddah decreased by −56.6%, −43.4%, and −32.3%, respectively, during April 2020, compared to April 2019. Rather, there was a small decrease in NO₂ levels in megacities like Tehran (−0.9%) and Cairo (−3.1%). Notably, during the lockdown period, there was a decrease in the mean intensity of nighttime SUHI, while the mean intensity of daytime SUHI experienced either an increase or a slight decrease across these locations. Together with the Gulf metropolitans (e.g. Kuwait, Dubai, and Muscat), the megacities (e.g. Tehran, Ankara, and Istanbul) exhibited anomalous increases in the intensity of daytime SUHI, which may exceed 2 °C. Statistical relationships were established to explore the association between changes in the mean intensity and the hotspot area in each metropolitan location during the lockdown. The findings indicate that the mean intensity of SUHI and the spatial extension of hotspot areas within each metropolitan had a statistically significant negative relationship, with Pearson's r values generally exceeding - 0.55, especially for daytime SUHI. This negative dependency was evident for both daytime and nighttime SUHI during all months of the lockdown. Our findings demonstrate that the decrease in primary pollutant levels during the lockdown contributed to the decrease in the intensity of nighttime SUHIs in the Middle East, especially in April and May. Changes in the characteristics of SUHIs during the lockdown period should be interpreted in the context of long-term climate change, rather than just the consequence of restrictive measures. This is simply because short-term air quality improvements were insufficient to generate meaningful changes in the region's urban climate.
Показать больше [+] Меньше [-]Polybrominated diphenyl ethers (PBDEs) in soils along a rural-urban-rural transect: Sources, concentration gradients, and profiles Полный текст
2011
Gevao, Bondi | Ghadban, Abdul Nabi | Uddin, Saif | Jaward, Foday M. | Bahloul, Majed | Zafar, Jamal
This study reports concentrations of PBDEs in surface soil samples collected along a 140km transect across Kuwait to assess the role of urban centers as sources of persistent organic pollutants to the surrounding environment. The ΣPBDE concentrations varied by a factor of ∼250 and ranged from 289 to 80,078pgg⁻¹d.w. The concentrations of PBDEs in Kuwait City were significantly higher (p<0.01) than those collected from sites outside the city supporting the hypothesis that urban centers are sources of PBDEs. The congener profiles were dominated by BDE-209, accounting for 93% of the PBDEs in the soil samples. The concentrations of all congeners (except BDE-209) were highly correlated with percent organic carbon (%OC) (p>0.05) when the data from Kuwait City was omitted from the analysis. These findings suggest that soil concentrations outside the urban centers were close to equilibrium with the atmosphere.
Показать больше [+] Меньше [-]Dynamic hydrographic and water-quality variations in the northwestern Arabian Gulf, a sinking zone of reverse estuarine circulation Полный текст
2022
Yamamoto, Takahiro | Madhusoodhanan, Rakhesh | Al-Said, Turki | Ahmed, Ayaz | Fernandes, Loreta | Nithyanandan, Manickam | Thuslim, Fathima | Alghunaim, Aws | Al-Zekri, Waleed | Naqvi, S. Wajih A. | Al-Yamani, Faiza
Continuous measurements of hydrographic, hydrodynamic, and water quality showed marked diurnal, tidal, and seasonal variabilities in Kuwait Bay, a stressed coastal system in the northwestern Arabian/Persian Gulf. Advection of water masses and seasonality in vertical mixing regulated the Bay's hydrographic and water quality properties. Intensive stratification in summer had substantial implications on the Bay environment. Kuwait Bay constantly exports dense bottom water laden with dissolved inorganic nutrients and organic matter to the central basin of the Gulf. The export was largest in August under strong water column stratification. These in-situ findings agreed well with earlier studies that corroborated Kuwait Bay as an important area where the phenomenon of reverse estuarine circulation originates in the Gulf. Thus, Kuwait Bay is a significant source of nutrients and organic matter to the Gulf Deep Water that flows into the core of the oxygen minimum zone in the northwestern Indian Ocean.
Показать больше [+] Меньше [-]Temporal trend of polychlorinated biphenyls contamination in the northwestern Arabian Gulf – Evidence from sediment records Полный текст
2022
Gevao, Bondi | Uddin, Saif | Behbehani, Montaha | Fowler, Scott W.
This study provides an insight into the polychlorinated biphenyls (PCBs) inventories in the sediments of the northwestern Arabian/Persian Gulf. PCBs can be used as chemical markers that correlate with historical events in the region, to estimate the sedimentation rates in the northern Gulf, and to determine the sources of pollutants in the study area. The concentrations of PCBs were generally patchy in sediments. At Station 1 the ΣPCB concentrations generally fluctuated between 0.100 and 0.400 ng g⁻¹ dw throughout the depositional history measured in a sediment core. There were four peaks in the ΣPCB profile corresponding to 1969, 1979, 1983 and 1991. Station 2 showed a prominent peak at depth of 25 cm. The concentrations of the ΣPCBs and ΣICE congeners at this depth were 28 and 12 ng g⁻¹ dw respectively. Concentrations then dropped dramatically thereafter by a factor of 4. The ΣPCB concentrations at Station 3 were very low compared to the concentrations measured at Stations 1 and 2. The PCB concentration in Core 4 which was taken from open waters was 2–3 orders of magnitude lower than those in the other coastal cores. However, a 1990–91 peak was omnipresent in these cores. There is no record of PCB production within the Gulf region, and PCB releases into the Kuwait marine environment are likely to originate from their use in products. These maxima in early-1990s can be correlated to inputs from war-related activities, including the reported destruction of PCB-containing transformers and military equipment during the occupation of Kuwait. None of the recent sediment core sections at the four stations had a ΣPCB concentration near the effects range-median (ERM) concentration of 180 ng g⁻¹, or permissible exposure limits (PEL) of 189 ng g⁻¹, or were above the effect range-low (ERL) values of 22.7 ng g⁻¹.
Показать больше [+] Меньше [-]Kuwait's marine biodiversity: Qualitative assessment of indicator habitats and species Полный текст
2021
The tropical waters of the Northern Arabian Gulf have a long history of maritime resource richness. High levels of biodiversity result from the complex matrix of coastal habitats, coral reefs and sea grass beds that characterise the region. Insight into the ongoing health of such habitats and the broader Kuwait maritime environment can be gauged by the status of indicator species found within these habitats. Here we review information on the occurrence, distribution and threats to key marine habitats and associated indicator species to provide an updated assessment of the state of the Kuwait's marine biodiversity. Critical evaluation of historic data highlights knowledge gaps needed inform the focus of future monitoring and conservation efforts. This assessment is designed to evaluate performance against environmental policy commitments, while providing a solid foundation for the design of comprehensive marine ecosystem management strategies.
Показать больше [+] Меньше [-]Baseline concentrations of pharmaceuticals in Kuwait's coastal marine environment Полный текст
2021
Gevao, Bondi | Uddin, Saif | duPont, Sam
This study was carried out to provide baseline information on the concentrations of pharmaceuticals in Kuwait's coastal waters. Samples were collected over four sampling campaigns from various outfalls that occasionally discharged water into the marine environment and analyzed for a range of pharmaceuticals including analgesic/anti-inflammatories, antibiotics, anticoagulant, antidiabetic, antihelmintics, antihypertensives, antiplatelet agent, asthma medication, β-blocking agent, calcium channel blocker, diuretic, histamine H1 and H2 receptor antagonist, lipid regulators/cholesterol-lowering, prostatic hyperplasia, psychiatric drug, sedation and muscle relaxant, synthetic glucocorticoid, tranquilizer and x-ray contrast media. The levels varied between the detection limits of the method and a maximum of 28,183 ng/L for analgesics/anti-inflammatories. The highest pharmaceutical concentrations were in samples collected during the September campaign, possibly linked to the increased prescription of these medications to treat infectious diseases and flu prevalent in Kuwait during the winter months. The spatial variation is concentration is evident with KISR site being most polluted as hospital wastewater is discharged at the site. This study provides the first dataset on the concentrations of pharmaceuticals in the seawater in Kuwait and possibly the wider Arabian Gulf. Kuwait's coastal water pharmaceutical concentrations derived from this study exceed those reported from the Spanish coast, the Hong Kong harbour, the Bohai and the Yellow seas. More studies are needed to evaluate the environmental impact that these residues may have on non-target organisms.
Показать больше [+] Меньше [-]World record extreme sea surface temperatures in the northwestern Arabian/Persian Gulf verified by in situ measurements Полный текст
2020
The Arabian or Persian Gulf is recognized as one of the warmest estuaries globally. The sea surface temperature (SST) has been utilized in several studies to gauge the global warming associated with climate change. In the current investigation we present detailed in situ SST measurements for five consecutive years (2016, 2017, 2018, 2019, 2020) in the northwest of the Gulf, specifically in Kuwait Bay. Results of data analyses were compared with the historical records for the region, revealing that the SST reached an extreme level never previously recorded either in the Gulf. The extreme SST in Kuwait Bay reached 37.6 °C, recorded by the offshore station KISR01 located in the middle of the Bay. The event was associated with heatwave, neap tides, and an extended period of Kous winds which are characterized by high humidity levels and accompanied by large-scale intermittent fish kill incidents that extended the full length of the Kuwait coastline. Several fish kill incidents were reported also at the northern edge of the Gulf along Shatt Al Arab stretch in Iraq. The species found dead during the incident varied considerably, unlike those found in the frequent summer incidents. The records presented in this study may provide evidence to the effects of global warming, aid further research, and encourage the concerned international government bodies to deliver urgent environmental policies.
Показать больше [+] Меньше [-]Hydro-environmental processes governing the formation of hypoxic parcels in an inverse estuarine water body: Assessment of physical controls Полный текст
2020
Alosairi, Y. | Alsulaiman, N.
Hypoxia is often thought of as the key factor responsible for fish kill events in coastal areas but fish kill events are too complex to be governed by a single factor. The events are influenced by a combination of chemical, biological and physical processes. Hydrodynamics play a key role in understanding the formation of hypoxia in shallow waters. This study aims to identify the settings of the physical forces that lead to a large-scale depletion of dissolved oxygen in Kuwait Bay at the northwest of the Arabian Gulf. The assessment, made with a validated three-dimensional numerical model (Alosairi and Alsulaiman, 2019), revealed that the pollution from the outfalls leads to nearfield depletion of dissolved oxygen but has only a minor effect on the bay-scale dissolved oxygen. This is a result of the strong dynamics of Kuwait Bay, which mixes the pollutant rapidly before it is transported seawards. Offshore, a low dynamic region has been identified near Jahra Bay which is susceptible to occasional dissolved oxygen depletion. Assessment of the physical forces revealed that the density-driven current and, to a greater extent the wind regime, controlled the formation of a hypoxic parcel near Jahra Bay. The combination of neap tides and low mixed winds reduced mixing and enabled the longer residence times of Kuwait Bay. These are the most critical circumstances, as the average dissolved oxygen can be reduced by 50% during summer. The circumstance resulting in low dynamics near Jahra Bay were also found to be effective in explaining algal blooms.
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