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Brick Kilns Air Pollution and its Impact on the Peshawar City Full text
2022
Hussain, Amjad | Khan, Naseer | Ullah, Munzer | Imran, Muhammad | Ibrahim, Muhammad | Hussain, Javid | Ullah, Hussain | Ullah, Irfan | Ahmad, Ikram | Khan, Muhammad | Ali, Meher | Attique, Faisal
In recent times, the brick kiln contributes to air pollution is one of the most emerging issues worldwide. In this research work, the Peshawar city, ambient air quality was measured, using a fixed air monitoring station to evaluate the impact of gaseous emission from brick kilns on ground level. In this study, the portable gas analyzer (PG-250) was used to quantify brick-based emitting carbon monoxide (CO), sulfur dioxide (SO2) and nitrogen oxide (NOx) from 3 brick kilns in the city of Peshawar. It was noticed that the average concentration of SO2 and NOx exceeds the National Environmental Quality Standards (NEQS) of Pakistan specifically, in terms of air quality. The brick kilns in District Peshawar have shown negative effects on the environment. It is necessary to take various measures to monitor the brick kiln embosom regularly before it becomes a significant risk for individuals. In conclusion, the impact of air pollution on physical activity and sedentary behavior at a specific time may be different.
Show more [+] Less [-]Extractive Treatment of Arsenic Contaminated Clay Soils (Vermiculite) Full text
2022
Abbaslou, Hanie | Ghofran Makshuf, Saeedeh | Bakhtiari, Somayeh | Ghanizadeh, Ali Reza | Shahrashoub, Meysam
In this research, the capability of vermiculite in arsenic extraction, associated with characterizing its main properties was evaluated. To address this purpose, vermiculite was artificially contaminated with arsenic at 7 and 28-day intervals. Then, arsenic was extracted from contaminated soils by different extractants. Various physical and mechanical tests were performed to investigate the effect of arsenic as an anionic contaminant on the properties of the vermiculite, as well as to evaluate how the properties of the contaminated soil were altered by the extraction process. The carbonate bonding phase was probably mainly responsible for the adsorption and fixation of arsenic with more than 50% portion among measured fractions at different curing times. Based on the vermiculite condition, hydrochloric acid was the best extractant for removing arsenic in all studied samples (around 3 -18 % more than other extractants). The clay soil demonstrated few changes due to arsenic contamination and modification. In general, the most promising characteristics of vermiculite as clay liner are its stability after contamination due to high CEC and SSA; however, its workability and strength (UCS between 110 to 220 kPa at different soil conditions) is a challenge and must be improved by adding coarser fractions like silt particles. In general, the results of this study regarding the effects of arsenic contamination and extraction onto vermiculite’s physical properties can provide appropriate information for researchers and geo-environmental engineers.
Show more [+] Less [-]The Optimal Performances of Starches from two Cassava varieties as Bioflocculants for the Treatment of Textile Wastewater Full text
2022
Ogbeh, Gabriel | Ominiyi, Daniel
The optimal performances of starches produced from two cassava varieties–Manihot aipi (SMA) and Manihot palmate (SMP) as bioflocculants for the treatment of textile wastewater were investigated in this study. The central composite rotatable design was used to investigate the effects of varying dosages of each cassava starch, wastewater-pH, and settling time on the turbidity removal from the wastewater with alum as the primary coagulant. Highly significant second-order multilinear quadratic regression models were developed from the experimental data, resulting in a very high coefficient of determination (r2) values of 0.999 for the SMA and 1.000 for the SMP models. The optimum cassava doses of 50 and 150 mg/L, pH-values of 6.5 and 8.0, and settling times of 95 and 77 minutes led to predictive maximum turbidity removals of 98.35 and 88.87%% with desirability functions of 0.95 and 0.63 for the SMA and SMP, respectively. The corresponding observed turbidity removal recorded at these optimum conditions were 88.72% and 88.52% for the SMA and SMP, respectively. At these optimum conditions, there was no significant difference between the predicted and observed turbidity removed from the wastewater at a p≤0.05 significance level. Verification of the Jar tests showed a good agreement between the experimental data and the models and confirmed that the SMA was superior to the SMP in supporting the alum to remove turbidity from the textile wastewater. As a result, the study revealed that Manihot aipi starch has more flocculating capability than Manihot palmate for the treatment of textile wastewater.
Show more [+] Less [-]Biological Treatment of Textile Wastewater by Total Aerobic Mixed Bacteria and Comparison with Chemical Fenton Process Full text
2022
Hossain, MD Sabbir | Sarker, Protima | Rahaman, Md. | Ahmed, Fee Faysal | Molla Rahman, Shaibur | Uddin, Md Khabir
Textile effluents are highly colored for synthetic dyes, cause significant water pollution due to high pH, TDS, EC, BOD, and COD content, and are harmful to aquatic species. Among different treatment processes, biological treatment process is considered as a promising approach. In this investigation, a mixed aerobic bacterial consortium was used for the treatment of wastewater. In addition, the fenton process with a normal sand filter was used for treatment and compared with the biological method. The mean values of BOD, COD, TDS, EC, DO, and pH in the raw wastewater indicated that the effluent was highly contaminated according to Bangladesh standard (ECR, 1997). Both the biological treatment process and fenton process separately showed promising removal of pollution load. The aerobic mixed bacterial consortium reduced TDS (66.67%), EC (60%), BOD (91.67%), and COD (85.45%) and fenton process reduced TDS (74.71%), EC (55.11%), BOD (88.33%), and COD (83.63%) compared to the raw effluent bacterial consortium simultaneously degraded dyes and decolorized the wastewater from dark deep green to transparent. Color removal for the mixed aerobic bacterial process after 72 hours of aeration was 58.57% and for the fenton process with a normal sand filter was 80%. BOD and COD removal percentages for aerobic mixed bacterial consortium showed higher removal efficiency than the fenton process with a normal sand filter. Though 92 hours of aeration showed the maximum satisfactory result, aeration time could be reduced to 72 hours which also satisfied the Bangladeshi standard (ECR, 1997).
Show more [+] Less [-]Determination of Dioxins and Polychlorinated Biphenyls Levels in Milk Samples from Capital and North of Iran Full text
2022
Azarchehry, Seyede Pegah | Ataie, Farangis | Hosseinkhani, Saman
High levels of dioxins and dioxin-like compounds in the food and their adverse effects on human health are of increasing concern. Since milk is one of the most essential human nutritional resources, the present study aims at determining dioxins and PCBs in raw milk samples from four farms in North of Iran and raw and pasteurized samples from three farms and five dairy factories in Vicinity of Tehran (capital of Iran). Total toxic equivalence (TEQ) of dioxin and PCBs have been determined, using the DR-CALUX® bioassay. Results reveal that all samples are contaminated with dioxins and PCBs, comparatively. The total dioxins and PCBs levels in raw milk samples from the north range from 4.08 to 0.97 pg/gfat and for the raw samples and pasteurized samples from Tehran Province from 1.89 to 0.63 pg/gfat and 0.1 to 0.03 pg/gfat, respectively. The mean concentration of dioxins/PCBs is higher in samples from the north of Iran. This may be because of the common method of removing domestic and agricultural disposal in this area.
Show more [+] Less [-]Assessment of Indoor Air Quality in Schools from Anatolia, Turkey Full text
2022
Babaoglu, Ulken Tunga | Ogutcu, Hatice | Erdogdu, Makbule | Taskiran, Funda | Gullu, Gulen | Oymak, Sibel
Air pollution damages children’s health in many different ways, through both chronic and acute effects. The aims of our research are to reveal the indoor air quality levels in schools. Subject and indoor air measurements were performed in 34 primary schools located in the Central Anatolia region. PM10, PM2.5, CO2, CO, CH2O, relative humidity, temperature, and total bacteria and fungus levels were measured. In the urban region, mean PM1 was higher than the other regions(p=0.029). PM10 and PM2.5 were higher in schools in rural areas. According to CO2 measurements, only one school was identified to be below the upper limit recommended by the WHO. Total microorganism concentration was exceeded in 44.1% of classrooms. Indoor PM1, PM2.5, PM10, CO2, total bacteria and fungus levels were high and above recommended limits. Human activities, movements of students could be considered the most important indoor factors for particle matter increase. Indoor parameters could be lowered by organizing the school environment.
Show more [+] Less [-]Presence of Microplastics in Freshwater Ecosystems: An Unheeded Emerging Concern – A Global Review Full text
2022
Mukhopadhyay, Patralika | Arkkakadavil Valsalan, Shibu
Plastic production has inevitably increased in the past few decades and is one of the diverse material used in today’s world. With this increasing production and wider use, the aquatic ecosystems have become the trash barrel for all kinds of plastic resulting in it becoming a looming spectre to the habitat and functions of both inland and offshore ecosystems. Plastic pollution is considered as an emerging global environmental concern which could significantly affect the biological diversity and may have potential to cause inimical effects on human health. These plastics have shown to gradually degrade into micro fragments and are reported to cause toxic effects on the aquatic organisms. In comparison to the studies on presence of microplastic in marine ecosystems, the studies on the presence of it in freshwater ecosystems have received relatively lesser attention although some studies have shown that the contamination is as grievous as that of in marine environment. This review article focuses on the literature available on the reports of microplastic occurrence, its distribution in freshwater ecosystems across the world and its insidious effects which are of emerging concern. The effect of such microplastic ingestion in both aquatic organisms and the potential health hazards due to such plastic consumption in humans have also been examined. The paper also discusses the existing knowledge gaps so that future research directions can be taken accordingly and the findings in this paper would significantly help all the countries across the world to understand the present plastic pollution scenario and work towards the mitigation of the same.
Show more [+] Less [-]The Effects of Occupational Noise Pollution and Shift Work on Oxidative Stress Markers in Cement Workers, Iran Full text
2022
Khavanin, Ali | Khajehnasiri, Farahnaz | Shahhoseini, Sara
Both noise and shift work generate oxidative stress, independently; however, in some work places workers are exposed to both at the same time, where their combined effect might increase the oxidative damage. This research is based on the question whether noise and shift work have a synergistic effect on oxidative stress or not. It tries to investigate the effects of these two factors simultaneously, at the biggest cement factory of Iran. For so doing, it enrols 88 male workers, equally in four groups, with one group serving as the control (i.e., Group 1 with 8 hours of fixed shift, exposed to less than 85 dB sound level) and three groups as the cases (Group 2 with 12 hours of rotational shifts, exposed to less than 85 dB sound level; Group 3 with 8 hours of fixed shift, exposed to more than 85 dB sound level; and Group 4 with 12 hours of rotational shifts, exposed to more than 85 dB sound level). Stress oxidative is evaluated by Malondialdehyde (MDA) and Superoxide dismutase (SOD). Finally, the results show that SOD levels (p<0.001) are significantly decreased in Group 4 and Group 3, compared to the control. Also, MDA levels are significantly increased in Group 4 (in which, the workers are exposed to noise and shift work simultaneously) compared to the control (p < 0.001). The current study shows that co-exposure to noise and shift work has a combined effect (a synergistic role) in MDA. Thereore, more attention should be paid to shift workers, who are exposure to noise simultaneously.
Show more [+] Less [-]Radiological Hazards Associated with 238U, 232Th, and 40K in some selected Packaged Drinking Water in Ilorin and Ogbomoso, Nigeria Full text
2022
Ajibola, Taiye Benjamine | Orosun, Muyiwa Michael | Ehinlafa, Olusegun Emmanuel | Sharafudeen, Fatimah Anike | Salawu, Banji Naheem | Ige, Simon Olatunji | Akoshile, Clement O.
In order to ensure radiation monitoring and protection, investigation and assessment of radiological risks that may be associated with the consumption of packaged table waters commonly consumed in Ogbomoso and Ilorin metropolis, Nigeria, was carried out. The measurements were carried out using a ‘3 x 3’ inch lead-shielded NaI (Tl) detector coupled through coaxial cable to a multichannel analyser. The measured activity concentrations of the natural radionuclides in the packaged drinking water sample are mostly within the recommended limits. The estimated mean Annual Effective Dose was found to be within the acceptable limits of 1 mSv/y for the general populace except for the infants which is slightly higher for some of the samples. The estimated Excess Lifetime Cancer Risk were found to be lower than the world average value of 0.2 x 10-3 in only two of the selected packaged drinking water. This implies the possibility of developing cancer over a lifetime considering seventy years as the average life span is considerably high.
Show more [+] Less [-]Nanocomposites for Packaging Applications: Synthesis, Characterization, Thermal and Microbial Degradation of Its Residues for Plant Growth Full text
2022
Abbasi, Zahra | Motamedi, Hossein | Zirrahi, Zinat | Taghavi, Mehdi | Farrokhnia, Abdolhadi | Aghaie, Ermia | Behnamian, Yashar
Environmental pollution, caused by traditional plastic packaging, has recently become more severe due to non-biodegradable nature of petroleum-based plastics. The present research studies the preparation of polyvinyl alcohol (PVOH)/Starch (ST)/Humic Acid (HA) contained sodium montmorillonite clay (MMT) as a plastic packaging method. It also investigates biodegradability of films in terms of microbial and thermal degradation and their residual effect on plant growth. For doing so, the research utilizes Broido Technique to obtain the activation energy of the films’ thermal degradation. The influence of HA/MMT ratio on the surface morphology and physical characteristics has also been assessed, using the Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscope (SEM), and thermogravimetric analysis (TA). After 12 days of microbial degradation, the total remaining solids are 32.12 wt% (PVOH/ST/HA (3%)/MMT (1%)); 48.17 wt% (PVOH/ST/HA (3%)/MMT (3%)), and 58.82 wt% (PVOH/ST/HA (1%)/MMT (3%)). The research shows that the highest activation energy for PVOH/ST/HA (3%)/MMT (3%) is 75 kJ/mol.
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