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Decolorization of Textile Dyes by Extracellular Enzymes Produced from Trametes sanguinea and Perenniporia taephropora Immobilized on Natural Media
2024
Siriorn Boonyawanich, Nipon Pisutpaisal and Saowaluck Haosagul
The color of textile wastewater is still a main problem in wastewater treatment by biological processes. The colored effluents from textile factories usually exceed effluent standards. Therefore, various innovations were developed to treat textile wastewater for decolorization in the effluents. This research aims to decolorize textile wastewater by immobilizing white rot fungi degradation. At first, the 11 fungal stains were tested to find the decolorized efficiency then the high decolorized efficiency fungal stains were immobilized on four material media, namely water hyacinth stalks, coconut husk, corn cob, and loofah. After that, the immobilized fungi were cultivated in the culture media at 30, 60, and 120 C/N ratios, respectively. The results showed that Trametes sanguinea and Perenniporia tephropora were two stains with a high decolorized efficiency of 68.8% and 67.5% respectively, and the decolorized efficiency was increased when immobilized on loofahs and fed with 120 C/N ratio medium. In a comparison of two fungal stains, P. tephropora was found more suitable for the decolorization of textile wastewater than T. sanguinea because T. sanguinea could produce red-orange pigments that induced the colored enhancement in wastewater over time. Finally, immobilized P. tephropora was cultivated in a 120 C/N ratio medium within a 10 L continuous stirred tank reactor (8 L working volume) to investigate the decolorized efficiency, enzymatic activity, and repeated batch. It was found that three repeated cycles were carried out by reusing the immobilized P. tephropora and the highest decolorized efficiency was 63.4%. The enzymatic activity of laccase, manganese peroxidase, and lignin peroxidase was 15.5 U/L, 85.9 U/L, and 0 U/L, respectively
Mostrar más [+] Menos [-]Evaluating the Stages of Environmental Pollution and Vital Indicators in the Qayyarah Refinery Area, Mosul, Iraq
2024
Juomana Jabbar Saeed, Maryam Jasim Hasan, Estabraq Mohammed Ati, Reyam Naji Ajmi, Abdalkader Saeed Latif and Hala Ahmed Rasheed
Oil spills can have varying degrees of impact on the aquatic environment depending on factors such as the type of oil spilled, the volume released, and the ecosystem affected because crude oil and refined petroleum contain harmful substances such as hydrocarbons, heavy metals, and toxic chemicals. When released into the water, these substances can have immediate and long-term effects on marine life. This research aims to find the factors affecting the degree of pollution from oil spills on the aquatic environment and the areas adjacent to the Qayyarah refinery in northern Iraq. Combines the fuzzy comprehensive evaluation method and the analytical hierarchy process to evaluate the degree of pollution from oil spill incidents in the areas adjacent to the refinery. The statistical analysis showed that there were statistically significant differences and that the value of the correlation coefficient was positive between exchanged cadmium, residual cadmium, exchanged lead, where the lead exchange rate ranged correlation coefficient at a minimum R² 0.674 and a clear increase in the number of bacteria indicating contamination the total number of bacteria coli, fecal coliform bacteria, and fecal strep bacteria (where the numbers of coliform bacteria ranged 102 × 102- (cells/011 mL, and fecal coliform bacteria were between 160 × 102 cells/011 mL. These rates are environmental and vital indicators of the presence of significant levels of organic pollution and evidence of the presence of microorganisms dangerous to the health of residents and living organisms.
Mostrar más [+] Menos [-]Stabilization of Dredged Soil by Compensating the Sand Content in the Jhelum River
2024
Yasir Hamid, Owais Shafi Malik, Huma Khan, Gauhar Mehmood and Amina Zakiah
River dredging is crucial for mitigating the risk of floods by enhancing the water-carrying capacity of rivers. Nevertheless, the key difficulty lies in the appropriate disposal of dredged material, resulting in escalated costs. Predominantly consisting of silt, the dredged material demonstrates constrained bearing capacity and strength. Nonetheless, there is a prospect to derive value from excavated sediments, with potential applications in diverse public works projects. The processed product derived from dredged material can serve diverse purposes, such as filling railway and highway embankments, as well as the subgrade of pavements. The comprehensive study involved analyzing the fundamental properties of the dredged material collected from the Allochibagh flood channel of the Jhelum River. The analysis focused on determining the basic geotechnical properties of the soil mass. The tests unveiled the fine and cohesive nature of the dredged soil. To enhance its properties, sand was introduced as a stabilizing agent in varying proportions. The investigation revealed an initial augmentation in compressive strength as the proportion of sand increased, attaining an optimal mixture whereafter the strength declined. This study explores the utilization of sand as a stabilizing agent for dredged soil to enhance its strength and optimize its application. The process of stabilizing dredged soil with sand demands a thorough examination of hydrogeological processes, the specific characteristics of the dredged soil, and the intricate transport of contaminants. This formal and multidisciplinary effort seeks to elevate the overall stability of the soil.
Mostrar más [+] Menos [-]The Risks and Safety Practices of Waste Pickers at Selected Dumping Sites in Pretoria, South Africa, During the COVID-19 Pandemic
2024
L. L. Mugivhisa, M. P. Mphitshana and J. O. Olowoyo
Amid the COVID-19 outbreak, the accumulation of household waste continued to rise as the number of COVID-19 patients increased. COVID-19 can survive and be transmitted from contaminated surfaces, making waste pickers more vulnerable and at risk of contracting and spreading the virus through contact with infected household waste. The study assessed safety practices and risks related to waste picking during the COVID-19 pandemic at two selected dumping sites in the north of Pretoria. Structured questionnaires were used to collect data from 81 waste pickers at these landfill sites. Results showed that 100.0% of waste pickers at Site A and 86.7% at Site B collected plastics; 96.7% at Site A and 90.5% at Site B collected bottles; and 100% at Site B and 95.5% at Site A collected metals. The majority, 92.0% at Site A and 90.0% at Site B, were aware of the dangers and risks associated with waste handling if protective gear was not worn. From sites A and B, 97.0% and 90% of the waste pickers respectively had heard of COVID-19, although 51.9% from both sites believed they could not contract COVID-19 while handling waste. Only 18.0% of waste pickers from Site A and 82.0% from Site B faced challenges with purchasing their own PPE. All waste pickers at Site A wore facial masks, whereas 86.0% at Site B did so. Regarding testing for COVID-19, 22.0% from Site A and 19.0% from Site B were tested, with 2.0% from Site A and none (0.0%) from Site B testing positive. It is recommended that all waste pickers be educated about COVID-19 transmission and provided with PPE during the pandemic.
Mostrar más [+] Menos [-]Microbial Fuel Cell: Optimizing Graphene-Sponge Anode Thickness and Chamber pH Using Taguchi Experimental Method
2024
Emilio Steven C. Navarro and Melissa May M. Boado
The rapid consumption of fossil fuels has led to calls to switch from non-renewable to renewable energy sources. Microbial fuel cells are a promising technology that simultaneously treats wastewater and produces power. This study used the Taguchi Experimental method to optimize anode thickness and pH to obtain the maximum power density of an air-cathode microbial fuel cell (ACMFC). The graphene-sponge (G-S) anode thickness and chamber pH were selected as operating parameters, with their corresponding levels. The L9 orthogonal array was chosen for the experimental design. According to the Taguchi Method, the optimum G-S anode thickness and chamber pH were determined to be 1.0 cm and 8.0, respectively. A confirmatory run was performed under these optimum conditions, and the maximum power density observed was 707.75 mW·m−3. Analysis of variance (ANOVA) was conducted to identify the percentage contributions of the operating parameters to the process, which were found to be 30.66% for pH and 69.34% for anode thickness.
Mostrar más [+] Menos [-]Heavy Metal Concentration in Fish Species Clarias gariepinus (Catfish) and Oreochromis niloticus (Nile Tilapia) from Anambra River, Nigeria
2024
E. B. Ogbuene, A. M. Oroke, C. T. Eze, E. Etuk, O. G. Aloh, F. E. Achoru, J. C. Ogbuka, O. J. Okolo, A. V. Ozorme, C. J. Ibekwe, C. A. Eze and S. Akatakpo
Studies have emphasized that the presence of heavy metals in freshwater fish represents a global public health issue. Nigeria, being a developing nation with less emphasis on the quality of seafood consumed by the residents, ranks this study very vital. The policy implication of this study is the advancement of a healthy population in contemporary Nigeria. Hence, this study assessed heavy metal concentration in two fish species, Clarias gariepinus (Catfish) and Oreochromis niloticus (Nile Tilapia), in the Anambra River. The sample included twenty fishes, of which eighteen were collected from the three sampling locations (the fish ports of Anambra River), namely Otu-nsugbe, Otuocha, and Ikemivite) while two control samples were collected from a pond about 200 m away from the river. The levels of heavy metals were determined using Varian AA 240 atomic absorption spectrophotometer (AAS). The results showed that the concentrations of heavy metals (cadmium and arsenic) in the sampled fishes from Anambra River exceeded the joint World Health Organization and Food and Agriculture Organization (FAO/WHO) standard for fish and fish product consumption, while the concentration of chromium, mercury, and lead are within the permissible limit. The study also showed the distribution of the heavy metals in the fish organ varies among fish species. Heavy metals occur higher in Clarias garepinus than in Oreochromis niloticus, while tissue preference for heavy metal accumulation is in the order of gill > liver > muscle. It was recorded from this study that the heavy metal concentration in the fish from the pond is generally higher than the fish from the river for some metals. The high level of heavy metals in the sampled fish was attributed to heavy metals contamination of the river as a result of various anthropogenic activities such as mining, burning of fossil fuel and emission from the exhaust of boats/vehicles, overuse of fertilizers and pesticides, discharge of effluent, sewage, and hospital waste. This study concluded that long-term consumption of fish from the river may pose health risks to the consumers due to the possible bioaccumulation of heavy metals, especially cadmium and arsenic. It was recommended that continuous monitoring of heavy metal levels in the fish and water, public awareness, and appropriate legislative provisions should be put in place to ensure that harvested fish and fish products may be safe for human consumption.
Mostrar más [+] Menos [-]A Comparative Review on Bisphenol A Sources, Environmental Levels, Migration, and Health Impacts in India and Global Context
2024
Sugata Datta, Abhishek Chauhan, Anuj Ranjan, Abul Hasan Sardar, Hardeep Singh Tuli, Seema Ramniwas, Moyad Shahwan, Ujjawal Sharma and Tanu Jindal
Bisphenol A (BPA) is a widely utilized chemical found in numerous everyday products, including plastic containers, food packaging, and thermal paper. Research has linked BPA exposure to a range of health concerns, encompassing developmental and reproductive issues, cancer, and obesity. Given India's status as one of the world's largest producers and consumers of plastic goods, understanding the potential risks associated with BPA exposure and its health impacts on the Indian population is of paramount importance. This paper conducts a comparative analysis of BPA sources, environmental levels, migration, and health impacts in India in comparison to other countries. By examining data from various nations, we aim to discern overarching trends and patterns in BPA exposure and its associated health effects. This analysis serves as a foundation for the development of policies and regulations designed to safeguard public health. While the Indian government has taken some regulatory steps, such as banning the production, import, and sale of BPA-containing polycarbonate baby bottles, there is a notable absence of specific regulations or bans on BPA in other food-contact materials (FCMs). Studies conducted in India have detected BPA in various food items, underscoring the potential risk of BPA exposure through food consumption. This emphasizes the urgent need for effective monitoring and control of BPA migration in FCMs within India. In conclusion, this comparative review underscores the imperative for ongoing research and rigorous monitoring of BPA exposure and its health impacts in India, as well as in other nations. Safeguarding the health of the general public necessitates a comprehensive understanding of BPA's prevalence, sources, and consequences. By implementing and refining regulations, such as extending bans on BPA in additional FCMs, policymakers can work towards mitigating the risks associated with BPA exposure and ensuring the safety of populations worldwide.
Mostrar más [+] Menos [-]The Effect of Senegal River Irrigation Water Quality on Soil Salinization: A Study of the Main Canal of the M’Pourie Plain in Mauritania
2024
Mewgef El Ezza dite Hanane Djieh Cheikh Med Fadel, B. A. Dick, E. C. S’Id, M. B. Ammar, Ould Sidi Y. M., L. S. Mohamed, Mohamed lemine Yehdhih and Mohamed Fekhaoui
In this study, the Senegal River, being the main source of water, plays a crucial role in the area’s agricultural development. Irrigation on the M’Pourie plain using water from the Senegal River is carried out without any prior sanitation control. An evaluation of the quality of irrigation water and its impact on soil salinization in different agricultural plots soil salinity is crucial for the effective utilization of traditional irrigation water over extended periods. Comprehensive physico-chemical analyses were conducted across nine locations on the M’Pourie plain in Rosso during the dynamic seasons of 2021-2023. Nevertheless, a relatively small number of studies have employed soil salinity indexing methods to examine the consequences of river irrigation on soil salinity. The analysis and interpretation of the results obtained were based both on classic methods (average and correlations) and more advanced techniques such as principal component analysis (PCA) and the Piper diagram which allow characterization and a spatial typology of water. Analysis of the Piper diagram highlights the distinction between two groups of water, weakly and moderately mineralized, ranging from 52.22 μS.cm-1 in the dry season to 72.22 μS.cm-1 in the rainy season, presenting a sodium-potassium bicarbonate facies The variability of irrigation water supplies, proves to be important in the functioning of an agro-systems. Two modes of operation have become individualized: the dry phase mode, characterized by very strong mineralization of the water linked to a significant load of dissolved elements, and the wet phase mode, whose water quality is poorly mineralized but shows the impact that its irrigation water can represent in the loading of organic and mineral pollution and the need for strict control of these waters upstream before their agricultural use. The results of this study show the absence of risks of soil salinization in relation to the chemical nature of irrigation water and the impact of agriculture on the M’Pourie plain.
Mostrar más [+] Menos [-]Study of Temporal Dynamics of Urban Heat Island Surface in Padang West Sumatra, Indonesia
2024
Rery Novio, Sri Mariya, Widya Prarikeslan and Sophia Aulia Ramon
Padang as the capital of the province, is a strategic area and also the center of the economy. Annual population growth affects changes in land use from vegetated land to built-up areas. An increase in barren land will trigger an increase in temperature. SUHI is a temperature phenomenon that occurs on the surface resulting from the increase in temperature. SUHI can be observed through surface temperature data or Land Surface Temperature. This study aims to identify changes in land surface temperature that are affected by changes in land use in the form of building density conditions. In analyzing this using Landsat 7 ETM+ imagery in 2001, 2006, 2011, 2016, and 2020. The building density measurement method LST transformations to measure surface temperature and helps the Surface Urban Heat Island phenomenon. The results of the analysis showed that there was an increase in the building density of the city of Padang over a period of 20 years. This phenomenon affects the surface temperature, indicating that the surface temperature has increased by around 0.47°C. The highest temperature from 2001-2020 occurred in 2016, with the highest temperature of 36°C.
Mostrar más [+] Menos [-]An Appraisal of the Legal Frameworks and Policy Shift in the Nigerian Energy Sector
2024
Michael Otu, Brian F. I. Anyatang, Bassey Kooffreh and Rose Ohiama Ugbe
This paper will explore policy shifts in Nigeria’s oil and gas, solar, nuclear, and mineral energy sectors. This policy shift by way of a transition, indigenization, and Nigerianization, has given way to deregulation, decentralization, and de-indigenization of many industries, most notably in the oil and gas sector, through the Petroleum Industry Act (PIA) of 2021 and the Local Content Act of 2010 (LCA). The paper recommends, amongst others, the establishment of a new legal regime that grants resource-based and property rights to resource-bearing communities and incorporates principles of international law, energy diplomacies, International Environmental Law, and international best practices.
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