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Human Health Risks Associated with Potentially Harmful Elements from Urban Soils of Hamedan City, Iran Full text
2021
Tashakor, Mahsa | Modabberi, Soroush
Previous studies have shown that certain urban elements and arsenic are significantly concentrated in the surface soils of Hamedan, the largest city in western Iran. This study was carried out to assess the non-cancer and cancer risks from exposure to these potentially harmful elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) for Hamedan residence. In so doing, thirty-one urban and three background soil samples were analyzed by ICP-MS and the Risk Assessment Model established by the USEPA was applied to assess the health risk. It was found that the hazard index values for all the concerned elements are below 1, which indicates negligible to low non-carcinogenic risk for the exposed population. Nevertheless, some close to threshold values were recognized for As, Cr, and Pb implying that these elements have the potential to cause non-cancer risk for Hamedan citizens in case of long-term overexposure. The contribution of HQ-ingestion to total HI was the highest while the health effect associated with the inhalation exposure was trivial. Children were found to be more susceptible to potentially harmful elements than adults. The cancer risk calculation revealed that both children and adults are at increasing risk of developing cancer over a lifetime through ingestion, inhalation, and skin contact. All of the verified elements exceeded the tolerable level (1×10-6) of cancer risk however arsenic and chromium were found to be the most carcinogenic elements followed by Pb, Ni, and Cd. The carcinogenic risks were moderate for adults and high for children. This study indicates the necessity of designing effective strategies to reduce elemental pollution and to mitigate adverse human health effects of PHEs in Hamedan.
Show more [+] Less [-]Environmental Pollution and Disaggregated Economic Policy Uncertainty: Evidence from Japan Full text
2021
Odugbesan, Jamiu Adetola | Aghazadeh, Sarah
Though, the attention of researchers on exploring the impact of economic policy uncertainty on carbon emissions is on increase, however, the impact of different types of economic policy uncertainty remains unexplored. Thus, this study investigates the impact of different types of economic policy uncertainty on carbon emissions in Japan. A monthly data from 1987M1 to 2019M12 was used, while the FMOLS, DOLS, CCR and ARDL estimators were employed for examining the cointegration among the variables, as well as the long- and short-run relationship between types of economic policy uncertainty and carbon emissions. The study findings revealed a long-run cointegration among energy consumption, per capita income, fiscal, exchange rate, monetary, and trade policy uncertainties and carbon emissions. Moreover, this study found energy consumption, exchange rate, monetary, and trade policy uncertainties to contribute significantly to the increase of carbon emissions in Japan. Finally, this study suggests that environmental policy makers in Japan should take into account the economic policy uncertainty so as to promote robust information for climate policy that will be targeted at ameliorating the carbon emissions in Japan.
Show more [+] Less [-]Particulate Matter and Adverse Respiratory Health Outcome: Exposure of Street Vendors in Kolkata city in India Full text
2021
Ghosh, Nabanita | Das, Biplob | Das, Nandini | Chatterjee, Souran | Debsarkar, Anupam | Dutta, Amit | Chakrabarty, Shibnath | Roy, Joyashree
Exposure to airborne particulates is a major occupational hazard especially for outdoor workers who spending time outdoors at ground level getting exposed to traffic fumes and roadside dust. Aim of this study was to assess respiratory health symptoms and determine the change of lung functions of the roadside vendors and its association with traffic-related exposures and their working experience. A cross-sectional study was conducted in key market places of Kolkata – Gariahat (GH), Esplanade-Park Street (EP), Shyambazar-Hatibagan (SH) and Behala (BE). Particulate (PM10 and PM2.5) levels and meteorological parameters (wind speed, temperature and relative humidity) were monitored in the morning, afternoon and night over the period of October 2019 to February 2020. Lung function status (FEV1, FVC, FEV1/FVC ratio and PEF) was measured for 111 purposively selected participants. PM concentration was observed higher in the morning and night peak hours for all sites. At SH area the average occupational exposure level for PM10 and PM2.5 were observed as 1502.22 μg/m3h and 684.01 μg/m3h. Percentage predicted FEV1 (%FEV1) of street vendors was found decreasing with their work experience and the worst-case scenario was observed in the EP area, with the corresponding value being 70.75%, 49.15% and 47.3% for less than 10 years, 10 to 20 years and more than 20 years participation respectively. The higher particulate burden was observed to have declining lung function status of the street vendors. A strong policy framework should be adopted to improve outdoor working environment for outdoor workers.
Show more [+] Less [-]Treatment Oilfield Produced Water using Coagulation/Flocculation Process (case study: Alahdab Oilfield) Full text
2021
Jabbar, Hussein Ali | Alatabe, Mohammed jaafar Ali
Produced water is a large amount of water wasted throughout the crude oil extraction process, it's a mixture of the well's deposition water and the water of oil wells extraction water. Produced water contains oil, suspended solids and dissolves solid. This study tested produced water collected from Alahdab oilfield/middle oil company for oil content and suspended solid contamination using chemical precipitation and coagulation-flocculation for reinjection and environmental considerations. Coagulation/flocculation is a common method used as primary purification to oily wastewater treatment due to its usability, performance, and low cost. Coagulant experimental was completed by A jar test device, additives of ferric sulfate and aluminium sulfate were in a range about (10 ـ 40) ppm, as well as polyelectrolyte- (polyacrylamide) as an additional flocculent in the range (1.5-3) ppm. The results show that ferric sulfate was more efficient at removing turbidity than aluminium sulfate under the same conditions, with the best removal of turbidity at dose concentration 30 ppm of Ferric sulfate and a flocculent dose concentration of 2.5 ppm of polyacrylamide, also with oil content decreasing from 396.71 ppm to 53.56 ppm.
Show more [+] Less [-]Exploring the use of Macrophytes as Biological Indicators for Organic Pollution of Chanchaga River in North Central Nigeria Full text
2021
Ali, Andrew | Obi-Iyeke, Grace | Keke, Unique | Arimoro, Francis
Macrophytes are creatures with low versatility and cannot stay away from any mix of streamflow, nutrient accessibility, and other physical and chemical attributes that impact their survival in the aquatic system. Sampling for macrophytes in Chanchaga River was conducted monthly for a 6-month period (May - October 2019). Sampling stations were selected at approximately equal distance along the streamline, the aquatic vegetation were surveyed, and some environmental variables were analysed using standard methods. Results obtained indicated that temperature ranged from 24.6-28.4°C; pH 6.4 -9.7; Electrical conductivity 28.0-79.0μS cm-1; Total dissolved solids 16-75 mg L-1; Dissolved oxygen(DO) 1.3-5.2 mg L-1; Nitrate 0.217-0.654 mg L-1; Phosphate 0.084-0.211 mg L-1; Biological oxygen demand (BOD) 0.89-5.4 mg L-1 and total alkalinity 8.00-11.00 mgL-1 for the study period. A total of eleven (11) macrophyte species belonging to ten genera and eight families were identified during the entire study. Variations in terms of families showed that Araliaceae was the most abundant followed by Poaceae, while Cyperaceae had more species throughout the study period. The high frequency of Araliaceae, Cyperaceae, and Poaceae families suggests that the environmental characteristics favour these species. We propose the use of Cyperus digitatus, Cyperus papyrus and Mimosa spp. as macrophytes indicators of organic pollution in Chanchaga River.
Show more [+] Less [-]Analysis of Water Quality Trends Using the Mann-Kendall Test and Sen’s Estimator of Slope in a Tropical River Basin Full text
2021
Hashim, Mohmadisa | Nayan, Nasir | Setyowati, Dewi Liesnoor | Said, Zahid Mat | Mahat, Hanifah | Saleh, Yazid
Trends in water quality, either increasing or decreasing over the long term, are becoming an essential guide to understanding water quality. This study aims to analyse the trends in water quality in the upstream part of the Bernam River Basin, Malaysia from 1998 to 2018. This study involved the collection of data on water quality from the Department of Environment, Malaysia. Six main parameters of the water quality index (WQI) were chosen, including the dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammoniacal nitrogen (NH3-N), total suspended solids (TSS) and pH. The analysis methods applied are the Mann-Kendall test and Sen’s estimator of slope. The results of the WQI value trend analysis revealed that most stations have decreasing trends. A trend analysis of the parameters found that most stations had increasing trends for the DO, BOD, NH3-N and pH parameters, while decreasing trends for the COD and TSS parameters were observed. An increasing trend indicated that the water quality parameters were getting better, and a decreasing trend indicated the opposite. This study will benefit the parties responsible for planning and monitoring developments to reduce water pollution around the upstream Bernam River Basin. In the upstream of Bernam River Basin, land use changes have occurred rapidly, especially forest areas have been explored for human settlements, agricultural and industrial activities. Thus, the sustainability of the river basin can be maintained and valued by the various parties in the future. The river basin is also important as a domestic water supply for the residents of Selangor and Perak.
Show more [+] Less [-]Production of Eco-Friendly Geopolymer Concrete by using Waste Wood Ash for a Sustainable Environment Full text
2021
Arunkumar, Kadarkarai | Muthukannan, Muthiah | Suresh Kumar, Arunachalam | Chithambar Ganesh, Arunasankar | Kanniga Devi, Rangaswamy
Climate change could be exacerbated by waste disposal problems, which destroy the ecosystem. Utilizing waste byproducts in creating eco-friendlier geopolymer concrete was hypothesised to be suitable and sustainable to overcome the negative impacts of wastes. The researchers had missed out on developing an alternate binder due to increasing demand for fly ash, high alkaline activators, and higher curing temperatures. This research used waste wood ash that is readily accessible in local restaurants and has an inherent potassium constituent. It has decided to replace the fly ash with waste wood ash obtained through nearby restaurants at intervals of 10 percent. The fresh and mechanical features have been discovered over long curing periods to assess the impact of waste wood ash. SEM and XRD have been used for characterising the microstructure of selected geopolymer mixes. In terms of setting properties and all mechanical parameters, replacing 30 percent waste wood ash produced enhanced results. The optimised mix could be used in geopolymer to replace fly ash and reduce the cost of alkaline activators while also reducing ecosystem damage.
Show more [+] Less [-]Effect of Co-existing Heavy Metals and Natural Organic Matter on Sorption/Desorption of Polycyclic Aromatic Hydrocarbons in Soil: A Review Full text
2020
Saeedi, M. | Li, Loretta Y. | Grace, John R.
Polycyclic aromatic hydrocarbons (PAHs), abundant in mixed contaminant sites, often coexist with heavy metals. The fate and remediation of PAHs depend heavily on the sorption and desorption behavior of these contaminants. The sorption behavior can in turn be highly affected by certain soil components and properties, such as soil organic matter (SOM) and the presence of heavy metals. Through review of the literature focused on research from 2006 to 2018, this paper discusses interactions, challenges, influencing factors and potential synergies in sorption/desorption of mixed PAHs and heavy metal contamination of soil. The presence of either natural organic matter or heavy metals can enhance the sorption capability of fine soil, retarding the PAHs in the solid matrix. The co-existence of SOM and heavy metals has been reported to have synergistic effect on PAHs sorption. Enhanced and surfactant desorption of PAHs are also affected by the presence of both SOM and metals. Remediation techniques for PAHs removal from soil, such as soil washing, soil flushing and electrokinetics, can be affected by the presence of SOM and heavy metals. More detailed studies on the simultaneous effects of soil components and properties on the sorption/desorption of PAHs are needed to enhance the effectiveness of PAHs remediation technologies.
Show more [+] Less [-]Emerging Pollutants in Aquatic Environment: Source, Effect, and Challenges in Biomonitoring and Bioremediation- A Review Full text
2020
Patel, N. | Khan, MD. Z. A. | Shahane, S. | Rai, D. | Chauhan, D. | Kant, C. | Chaudhary, V. K.
Emerging contaminants are distributed in to the environment from various anthropogenic activities. These Emerging contaminants (ECs) are mainly composed of products, such as pharmaceuticals, personal care products (PCPs), surfactants, plasticizers, pesticides etc. The present conventional system of waste treatment are not designed to treat these contaminants. Complex structure of these pollutants and their existence at low concentration makes them untraceable and hence found to be difficult in removal of these by present waste treatment. These chemicals are considered as threat to human health and environment. Therefore, disposal and treatment of these chemicals of emerging concern have been a key concern in the field of water treatment and its reuse. Biosensors can be used for biomonitoring of these contaminants with of biological system. Bioremediation plays an important role in the treatment of these pollutants of emerging concern. This review discusses about the sources, effects, and challenges in biomonitoring and bioremediation related to these emerging contaminants.
Show more [+] Less [-]Optimization of Crystal Violet Adsorption by Chemically Modified Potato Starch Using Response Surface Methodology Full text
2020
Bahrami, M. | Amiri, M. J. | Bagheri, F.
In this research, a response surface methodology (RSM) was used to investigate the effects of independent parameters (pH, contact time, temperature, adsorbent dosage, and initial concentration of pollutant), their simultaneous interactions, and quadratic effects on crystal violet adsorption onto two starch based materials in the form of batch experiments. The characterizing results indicated that there is no significant difference between the potato starch and synthesized starch phosphate, as phosphorylation has not changed the crystalline structure of starch inside the granules. The maximum removal efficiency of crystal violet ions was obtained 99 % at the optimum adsorption conditions of initial concentration 213.54 mg/L, adsorbent dosage 0.25 g, contact time 14.99 min, temperature 15 °C, and initial pH of solution 9. RSM outputs showed that the maximum adsorption of crystal violet ions by could be achieved by raising pH and adsorbent dosage, and decreasing the initial crystal violet concentration. While temperature and contact time are not effective parameters in crystal violet removal from aqueous solutions using synthesized starch phosphate. Generally, the RSM model is suitable to optimize the experiments for dye elimination by adsorption, where the modified starch phosphate would be an effective adsorbent for treating crystal violet solution.
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