Health risk of arsenic in the alluvial aquifers of Lahore and Raiwind,Punjab Province,Pakistan: an investigation for safer well water

Environmental pollution has generated release of high amounts of arsenic (As) which ultimately are detected in the water of Indus Basin Punjab, Pakistan. The area is characterized by a semiarid climate, and alluvial deposits. This investigation, an extension of previously reported As-affected area in Lahore and Kasur, aimed to (1) assess the extent of water contamination in this area and (2) determine possible safer sites for future water use. In a comparative study, total As contamination of underground water from individual dwellings and community water supply of some villages located at the boundary of the Sheikhopura and Lahore districts, Pakistan were measured to compare with previously published data of villages located at the boundary of the Lahore and Kasur districts. The results showed variable levels of As in shallow drinking water wells and average concentration exceeding WHO guidelines value. As levels ranged from below 5.2 to 80 µg/L and mean 45.5 µg/L. The As concentrations were higher than WHO limits but lower than previous studied area. In addition, high salinity was found to be a serious concern for deteriorating groundwater quality rendering it unsuitable for drinking. Groundwater is predominantly of the Na–HCO₃ type with slightly alkaline pH. High pH values and competition of As with HCO₃ may serve as an important process for mobilization of As in the shallow groundwater of the region. Continuous monitoring and expansion of monitoring systems are necessary to establish safer wells within As-contaminated areas.     

Production and growth of microalgae in urine and wastewater: A review

Environmental Chemistry Letters - Issues of climate change, energy demand, and natural resources depletion are calling for circular methods to produce value-added products such as biomass, biofuel,...     

Synthesis of magnetite-based nanocomposites for effective removal of brilliant green dye from wastewater

Environmental Science and Pollution Research - The present study aims at evaluating the batch scale potential of cotton shell powder (CSP), Moringa oleifera leaves (ML), and magnetite-assisted...     

Revealing empirical association among ecological footprints,renewable energy consumption,real income,and financial development: a global perspective

Environmental Science and Pollution Research - This study quantifies the effect of real income, financial development, trade openness, and renewable energy consumption on the ecological footprint...     

Air quality modeling for effective environmental management in the mining region

Air quality in the mining sector is a serious environmental concern and associated with many health issues. Air quality management in mining regions has been facing many challenges due to lack of understanding of atmospheric factors and physical removal mechanisms. A modeling approach called the mining air dispersion model (MADM) is developed to predict air pollutants concentration in the mining region while considering the deposition effect. The model takes into account the planet’s boundary conditions and assumes that the eddy diffusivity depends on the downwind distance. The developed MADM is applied to a mining site in Canada. The model provides values for the predicted concentrations of PM₁₀, PM_2.5, TSP, NO₂, and six heavy metals (As, Pb, Hg, Cd, Zn, Cr) at various receptor locations. The model shows that neutral stability conditions are dominant for the study site. The maximum mixing height is achieved (1280 m) during the evening in summer, and the minimum mixing height (380 m) is attained during the evening in winter. The dust fall (PM coarse) deposition flux is maximum during February and March with a deposition velocity of 4.67 cm/sec. The results are evaluated with the monitoring field values, revealing a good agreement for the target air pollutants with R-squared ranging from 0.72 to 0.96 for PM_2.5, from 0.71 to 0.82 for PM₁₀, and from 0.71 to 0.89 for NO₂. The analyses illustrate that the presented algorithm in this model can be used to assess air quality for the mining site in a systematic way. Comparisons of MADM and CALPUFF modeling values are made for four different pollutants (PM_2.5, PM₁₀, TSP, and NO₂) under three different atmospheric stability classes (stable, neutral, and unstable). Further, MADM results are statistically tested against CALPUFF for the air pollutants and model performance is found satisfactory.

Implications: The mathematical model (MADM) is developed by extending the Gaussian equation particularly when examining the settling process of important pollutants for the industrial region. Physical removal effects of air pollutants with field data have been considerred for the MADM development and for an extensive field case study. The model is well validated in the field of an open pit mine to assess the regional air quality. The MADA model helps to facilitate the management of the mining industry in doing estimation of emission rate around mining activities and predicting the resulted concentration of air pollutants together in one integrated approach.     

Impact of storm water on groundwater quality below retention/detention basins

Groundwater from 33 monitoring of peripheral wells of Karachi, Pakistan were evaluated in terms of pre- and post-monsoon seasons to find out the impact of storm water infiltration, as storm water infiltration by retention basin receives urban runoff water from the nearby areas. This may increase the risk of groundwater contamination for heavy metals, where the soil is sandy and water table is shallow. Concentration of dissolved oxygen is significantly low in groundwater beneath detention basin during pre-monsoon season, which effected the concentration of zinc and iron. The models of trace metals shown in basin groundwater reflect the land use served by the basins, while it differed from background concentration as storm water releases high concentration of certain trace metals such as copper and cadmium. Recharge by storm water infiltration decreases the concentration and detection frequency of iron, lead, and zinc in background groundwater; however, the study does not point a considerable risk for groundwater contamination due to storm water infiltration.     

Effect of oxygenated liquid additives on the urea based SNCR process

An experimental investigation was performed to study the effect of oxygenated liquid additives, H₂O₂, C₂H₅OH, C₂H₄(OH)₂ and C₃H₅(OH)₃ on NO_x removal from flue gases by the selective non-catalytic reduction (SNCR) process using urea as a reducing agent. Experiments were performed with a 150 kW pilot scale reactor in which a simulated flue gas was generated by the combustion of methane operating with 6% excess oxygen in flue gases. The desired levels of initial NO_x (500 ppm) were achieved by doping the fuel gas with ammonia. Experiments were performed throughout the temperature range of interest, i.e. from 800 to 1200 °C for the investigation of the effects of the process additives on the performance of aqueous urea DeNO_x. With H₂O₂ addition a downward shift of 150 °C in the peak reduction temperature from 1130 to 980 °C was observed during the experimentation, however, the peak reduction efficiency was reduced from 81 to 63% when no additive was used. The gradual addition of C₂H₅OH up to a molar ratio of 2.0 further impairs the peak NO_x reduction efficiency by reducing it to 50% but this is accompanied by a downward shift of 180 °C in the peak reduction temperature. Further exploration using C₂H₄(OH)₂ suggested that a 50% reduction could be attained for all the temperatures higher than 940 °C. The use of C₃H₅(OH)₃ as a secondary additive has a significant effect on the peak reduction efficiency that decreased to 40% the reductions were achievable at a much lower temperature of 800 °C showing a downward shift of 330 °C.     

The mediating role of ICTs in the relationship between international tourism and environmental degradation: fit as a fiddle

Environmental Science and Pollution Research - The United Nations sustainable development goals (SDGs) proposed 17 effective plans linked with three principal aims, i.e., eradicating poverty,...     

Air pollution and its economic impacts at household level: willingness to pay for environmental services in Pakistan

Environmental Science and Pollution Research - Air pollution has become a major global problem. Thus, the goal of this study was to find out the economic impacts (treatment cost) of air pollution...     

Climate risk insurance in Pacific Small Island Developing States: possibilities,challenges and vulnerabilities—a comprehensive review

Climate change has become one of the most compelling fields of empirical research over the last couple of decades, partly due to its socio-economic impacts. Using a meta-analysis of 235 peer-reviewed articles published between January 2010 and July 2020, this paper appraises climate change adaptation (CCA) research in Nepal and draws lessons for future adaptation planning. The number of research is observed to have increased significantly in recent years (2015–2020) although there is no consistent pattern over the review period and at the thematic level. Findings submit that the agriculture and food security has the highest number of publications (37%) followed by gender equality and social inclusion (18%) and forest, biodiversity and watershed management (16%). There are no studies found in rural and urban settlement theme. Geographic distribution of CCA studies revealed that over 40% studies were carried out from central Nepal, while no study was conducted in ten districts of eastern and western Nepal. The study focus was also discrete, and the perception and attitude and impact assessment of climate change were common agendas; however, the drivers of change and options for adaptation were understudied. CCA with multipronged initiatives provide a broader understanding of dynamics and governance of climate change that not only affects rural livelihoods, but also influences regional and global environments and biodiversity.