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Health Risk Assessment of Heavy Metals in Soil from the Iron Mines of Itakpe and Agbaja, Kogi State, Nigeria
2018
Aluko, Tope | Njoku, Kelechi | Adesuyi, Adeola | Akinola, Modupe
The study evaluates associated health risks of heavy metals in the soil to inhabitants of two mining areas of Nigeria. For so doing, it collects and analyses nine homogenous soil samples for their lead, copper, cadmium, zinc, and chromium levels, using AAS. The samples are then used to calculate health risks to adults and children. For adult population in Agbaja community, the calculated hazard quotients fall below one in all considered pathways. Hazard index values for all the pathways are also less than one, taking the following order: Cu>Cr>Pb>Cd>Zn. It is shown that for all considered heavy metals, the adult population in Agbaja mining community was not at any risk of non-carcinogenic effects from these metals. As for the children in Agbaja, the calculated HQ values for Cd and Zn have been less than one in all the pathways, while the HQ values for Pb, Cr, and Cu have significantly surpassed 1, with the ingestion route being the main pathway. The HI values have been in the following order: Cu>Cr>Pb>Cd>Zn, which poses serious non-carcinogenic health risks to the children, living around this community. The carcinogenic risk has been calculated based on Pb, Cd, and Cr, with the former (Pb) proven to be the highest contributor to cancer risk. USEPA considers acceptable cancer risk within the range of 1×10−6 to 1×10−4. Though insignificant in its values, carcinogenic risk for adults in Agbaja (2.95×10-4) and Itakpe (4.71×10-4) and for children in Itakpe (4.47×10-4) have been higher than the acceptable values. Hence, the adults are more at risk, for whom ingestion is the main contributor to excess lifetime cancer risk, followed by dermal pathways. Considering the health hazards, entailed by the accumulation of these heavy metals, on human health, mining sites and areas require to get monitored properly.
Show more [+] Less [-]Physiological Evaluation of Apricot (Prunus armeniaca L.) Leaves to Air Pollution for Biomonitoring of Atmospheric Quality
2018
zouari, M. | Elloumi, N. | Mezghani, I. | labrousse, P. | Ben Rouina, B. | Ben Abdallah, F. | Ben Ahmed, C.
Industrialization releases significant amounts of various air pollutants such as F, Cd, Pb, particulate matter, etc., which can in turn have a deleterious effect on a variety of biochemical and physiological processes as well as the structural organization within the cells. Responses from plants species to air pollutants is varied with certain species being very sensitive to such pollutants, ending up with well visible and measurable symptoms. Morphological damage is generally visible through lesions on the aerial parts, while biochemical and physiological changes which are invisible can be measured and quantified. This study has been designed to investigate the biochemical and physiological biomarkers of apricot (Prunus armeniaca L.) exposed to air pollution. It has been observed that, in comparison to unpolluted sites, lipid peroxidation level has increased in the leaves of apricot trees, grown in polluted areas, whereas photosynthetic capacity (Net photosynthesis, stomatal conductance, transpiration rate, total chlorophyll, and carotenoids) along with osmotic regulator (proline and soluble sugars) levels have declined. In P. armeniaca leaves, these symptoms can be used as indicators of air pollution stress for its early diagnosis, making them a reliable marker for a particular physiological disorder.
Show more [+] Less [-]Impact of Environmental Quality Variables and Socio-Economic Factors on Human Health: Empirical Evidence from China
2018
Ahmad, M. | Ur Rahman, Z. | Hong, L. | Khan, S. | Khan, Z. | Naeem Khan, M.
Carbon dioxide (CO2) is the foremost gas, emanated from human activities, and the best-known greenhouse gas, contributing to global warming, thus its negative effect on human health cannot be disregarded. The current paper investigates the relation between environmental quality variables, socio-economic factors, and human health from 1960 to 2014 in China, using Auto Regressive Distribution Lag (ARDL) Model. It selects three main environmental quality indicators (carbon emissions from coal, natural gas, and petrol) along with two representative socio-economic factors variables (per capita income and urban population) to explain the interaction mechanism. The results validate the long-term negative equilibrium impact of carbon emissions from the consumption of natural gas, coal, and petroleum on human health. The findings also reveal that migration from the countryside to cities and increase in per capita income improve quality of health. It is suggested that lowering emission of Carbon dioxide (CO2), which is the principal cause of greenhouse gas emissions, should be important in setting up the high quality of life for citizens.
Show more [+] Less [-]A Comparative Assessment of State of Environment Report in Tehran and Sydney, With an Emphasis on Sustainable Cities’ Criteria
2018
salehi, E. | ghorbani, S. | Rahimi, L. | salehi, R.
One of the most comprehensive tools to show the changing trend in urban ecosystems is by providing periodic State of Environment Report (SoER) for cities in national programs, wherein it is quite essential to have a truthful and realistic view of the current state of the environment as well as significant human impacts. Developing countries like Iran are faced with incoherent and deficient SoER; due to lack of data, which originates from neglecting environmental issues such as poverty, overpopulation, etc. The present study makes a comparative assessment of Tehran and Sydney's SoER in terms of sustainable urban environment indicators with the purpose of recognizing the weaknesses and strengths as well as finding the most important gaps in Tehran's SoER, which can be a useful resource for decision-makers. Results indicate the necessity of establishing integrated urban environmental management. On the whole, this paper recommends programs of environmental development and implementation as suggested strategies to reduce uncertainty and increase the reliability of SoER in the study area.
Show more [+] Less [-]Anthropogenic share of metal contents in soils of urban areas
2018
Fazeli, G. | Karbassi, A.R. | khoramnejadian, Sh. | Nasrabadi, T.
In the present investigation, 41 soil samples were subjected to single step chemical partitioning to assess the lithogenic and non-lithogenic portions of metals in Tehran's soils. The share of various studied metals in the anthropogenic portion ranges from as low as 0.2% to as high as 85% of bulk concentration. Geo-accumulation index (Igeo) showed that Cd falls within "heavily contaminated" soils. It might be inferred that Ni, Cu, Cr, Zn, Co and Ca fall within "Deficient to minimal" class in accordance with enrichment factor (EF) classification.. Enrichment factor values (to some extents) match with the chemical partition studies results (except for Ni and Cr). The very low Ca content of soil samples could be indicative of low biological productivity in the Tehran's soil. Also the very low concentrations of Mn could be indicative of reducing environment in soils of Tehran.
Show more [+] Less [-]Ecological risk assessment of heavy metals in Hurghada coastal sediment, Red Sea, Egypt
2018
Abdelkader, A. I. | Abuelregal, M. | El-Metwally, M.E. | Hassaan, M. A. | Sanad, E. F.
Twenty samples of Ø3, Ø4 and Ø5 (fine fractions) were collected from four coastal areas (Sheraton, Magawish, Marina and Al mina) in Hurghada, Egypt. Total organic matter (TOM), total organic carbon (TOC) and heavy metals were estimated in the recommended fractions. Results showed that Fe and Pb recorded the highest concentrations with 71.7 and 39 mg/kg respectively. Marina area fractions has the highest carbonate content varied between 50.7 and 65.7 while Magawish area fractions have the lowest organic matter content and carbonate between 10% and 9.40%. On the other hand, Sheraton area has the highest organic matter content. The Principal Component Analysis) PCA) indicate the anthropogenic sources of Zn and Pb at the Red Sea coast based on Sediment Quality Guidelines(SQGs).According to the Enrichment factor (EF) and the geo-accumulation factor (Igeo), Cu and Pb were the highest enriched elements due to anthropogenic contamination; consequently, the studied areas were classified as moderately to highly contaminate by Cu and Pb at Hurghada.
Show more [+] Less [-]Physico-chemical and bacteriological characterization of surface water in Djendjen River (North Eastern Algeria)
2017
Krika, Abderrezak | Krika, Fouad
Djendjen River is one of the largest rivers in the region of Jijel (Algeria). Human activities such as urban discharges, industrial, agricultural, and livestock have significant effects on the quality of water. The present study attempts to evaluate the quality of water along the banks of the Djendjen River at different sampling sites, using physico-chemical and bacteriological methods. The collected samples are analyzed per standard method parameters and measured in situ. The mean values of the physico-chemical parameters of the river water samples are consistently lower than the levels, certified by the Algerian standard (exept for pH and PO43-). The total and fecal coliform surpasses the Algerian standard limits (0 cfu/ 100 ml) at all sites, signifying that without treatment the water is unsuitable for human consumption. Results reveal that water quality of the Djendjen River is generally affected by the anthropogenic activities, taking place along its banks. The moderate organic pollution (OPI= 2-2.6) and high faecal contamination (MQI=3-3.25) of water in the study area has adverse impacts on the environment and public health, which requires a combined treatment (biological and physicochemical).
Show more [+] Less [-]Comparison between Water Quality Index (WQI) and biological indices, based on planktonic diatom for water quality assessment in the Dong Nai River, Vietnam
2017
Pham, Luu
The present study aims to have a comparative study of the results, from biological monitoring as well as conventional method, based on physico-chemical variables. Water quality index (WQI) and planktonic diatom metrics have been used to determine water quality and ecological conditions of the Dong Nai River (DNR) and Canonical Correspondence Analysis (CCA) to find out the main environmental variables that regulate the phytoplankton community. A total of 51 planktonic diatom species, belonging to 23 genera, have been identified during the study period. Fragillaria was the most dominant diatom in the upper course site, while the Aulacoseira was the most dominant species in the middle and lower ones. One-way ANOVA showed that the mean of turbidity, ammonium, nitrate, and phosphate were significantly different (P<0.05) among upper, middle, and lower course sites in both dry and wet seasons. The WQI showed that water quality in the Dong Nai River was classified in medium level at all sites, while water quality varied from good, moderate, to low level, based on the Biological Diatom Index (BDI) values. CCA indicated that nutrients (PO43-, NO3-, NH4+) and turbidity were the most important factors, regulating the variation in structure of the planktonic community. In this study, the BDI has been applied for the first time to bio-monitor water quality in Vietnam. The sensitivity of the BDI to environmental stressors, supported the use of this index to bio-monitor surface water in tropical regions.
Show more [+] Less [-]Evaluation of Faryab spring hydrochemistry in Hormozgan Province, Southern Iran
2017
Asadpour, Gholamabbas
With a mean precipitation rate, much lower than that of the world, Iran is among the countries that face severe water challenges. The present study has dealt with the evaluation of hydrochemistry of Faryab spring water in Hormozgan Province, Iran. Four different composite water samples have been analyzed to detect major anions, cations, total dissolved solids, electrical conductivity, pH, and sodium absorption ratio. The dominant water type was detected as sodium-chloride, with remarkable high concentration of sodium and chloride ions that makes it unfit for drinking purposes. Regarding irrigation use, high values of electrical conductivity (29989 to 31983 µS/cm) and sodium absorption ratio (SAR) (58.1 to 61) indicate a very high risk level for salinity and sodium alkali hazards, respectively. Abundance of secondary minerals such as halite and gypsum is considered to be the main reason for remarkably-high TDS values. Intensity of salt domes within the area would also facilitate solution/dissolution process of Na+ and Cl- into water column.
Show more [+] Less [-]Evaluation of seasonal variability in surface water quality of Shallow Valley Lake, Kashmir, India, using multivariate statistical techniques
2017
Najar, Ishtiyaq | Khan, Anisa | Hai, Abdul
Seasonal variation in water quality of Anchar Lake was evaluated using multivariate statistical techniques- principal component analysis (PCA) and cluster analysis (CA). Water quality data collected during 4 seasons was analyzed for 13 parameters. ANOVA showed significant variation in pH (F3 = 10.86, P < 0.05), temperature (F3 = 65, P <0.05), Electrical conductivity (F3 = 32.72, P <0.05), Calcium (F3 = 36.84, P <0.05), Magnesium (F3 = 16.52, P <0.05), nitrate-nitrogenSeasonal variation in water quality of Anchar Lake has been evaluated, using two multivariate statistical techniques, namely Principal Component Analysis (PCA) and Cluster Analysis (CA). Water quality data, collected during four seasons, have been analyzed for 13 parameters and ANOVA has shown that pH (F3= 10.86, P < 0.05), temperature (F3 = 65, P < 0.05), electrical conductivity (F3= 32.72, P < 0.05), Calcium (F3= 36.84, P < 0.05), Magnesium (F3= 16.52, P < 0.05), nitrate-nitrogen (F3= 48.06, P < 0.05), ammonical nitrogen (F3 =198.75, P < 0.05), and dissolved oxygen (F3= 4.96, P < 0.05) varied by season, whereas the substantial variations of sodium (F2= 7.18, P <0.05), phosphate-phosphorous (F2= 25.31, P < 0.05), biological oxygen demand (F2= 11.02, P < 0.05), and chemical oxygen demand (F2=37.73, P < 0.05) were based on different sites. CA has grouped the three sampling sites throughout the four seasons into three clusters of similar water quality as relatively Less-Polluted (LP), Medium-Polluted (MP), and Highly-Polluted (HP). In addition, PCA has been applied on the extract to recognize the factors, responsible for water quality variations in four seasons of the year, resulting in four principal components for winter, summer, and autumn, five ones for spring, accounting for 79.58%, 89.07%, 83.34%, and 93.13% of total variance respectively. Thus the factors, responsible for water quality variation, are mainly related to domestic wastewaters, seasonal variation, agricultural runoff, and catchment geology. These results will help decision-makers better understand the influence of various factors on water quality and manage pollution/eutrophication adaptively in Anchar Lake.
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