Pollution
Volume:8 Issue: 1, Winter 2022

The present study aims at determining the geotechnical properties of the tailings and the natural bed at Iran Mineral Processing Company, Sites 1 and 5. It qualitatively studies the subsurface layers of the company’s tailings storage site. After drilling different boreholes and conducting in-situ tests, it has made laboratory analyses in the form of field exploration to determine the geotechnical parameters of the extracted samples. Results from the analyses show the permeability coefficient of the subsurface layer of Site No. 1 and 5 to be very small, in the range of 10-7 cm/sec. Considering the conformity of permeability coefficient, percentage of fine grains (98% to 99%), plasticity index (28.5-29.5), and clay content of different layers of Sites 1 and 5 (68%-80%), based on the compacted clay liner criteria, it can be concluded that by nature, the subsurface layers of the mentioned sites are sealed with no need for any compacted clay liner. The tailings for storage Site 5 are fine-grained (80-88<75mm), basically in ML range according to USCS system, with a permeability coefficient of about 10-6 cm/sec. Therefore, the tailings themselves act as a relatively primary sealing layer against the infiltration of hazardous leachates into the natural bed. The method, used in the process of site selection of tailings storage facilities (TSF), can cut the construction time as well as the expenditures, thus reducing the production costs in the long run.

The present study evaluates the water quality of Dez River, a river 23 km long, via QUAL2Kw model, based on simulation of DO and BOD5 p98arameters, through considering water quality standards during six months in three stations of Kashefieh, Pole-Panjom, and Hamidabad. To determine the model’s validity and compare the observational data, the paper uses the square mean square error (RMES) and the squared mean square error coefficient (CV). The achieved results of the model largely indicate the actual conditions of the river, which represent the ability of QUAL2Kw model to simulate qualitative parameters. The main contamination of Dez River comes from municipal wastewater, either directly imported by river residents or collected by urban canals. It, then, enters the river at a certain point. Based on the simulation and observational results of DO at two stations of 5th and Hamidabad Bridge in all months of sampling, it is below 5 mg/L, regarded a threat to aquatic life. In addition, BOD5 parameter goes beyond 6 mg/L in Hamidabad station, being a threatening factor for aquatic life in this station. Critical conditions of Dez River, low discharge, and high loading of pollutants have increased the concentration of water quality parameters. Given the results of RMSE and CV parameters, the model has had the best conformity for DO parameter, followed by BOD5.

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.

Aquatic environments, including wetlands, are one of the most threatened ecosystems worldwide. Considering their ecological importance, wetlands are rightly appraised as ‘natural kidneys’. In this current study, the city wetlands of Guwahati were viewed for the first time through the angle of lesser-explored bottom dwellers. Guwahati, a rapidly expanding metropolis, is the gateway to northeast India, part of an Indian biodiversity hot-spot region. This case study comprised the bridge between abiotic and biotic factors, thus directing the pave for characterization of wetlands through benthos analysis. The study, covering seasons, viz. winter, premonsoon and monsoon, revealed 15 definite taxa belonging to 10 orders. The dominance of Chironomidae and Culicidae in certain wetlands indicated high tolerance of Dipterans in a wide range of aquatic environments, including polluted water bodies. Similarly, the presence of Trichopterans, only in the wetland located distant from the mainland city, marked that with less anthropogenic impacts. The Shannon indices for benthos were in the range from 0.17 to 0.97. Density was found to have a significant positive correlation with dissolved oxygen (r = 0.567) and a negative correlation with free carbon dioxide (r = -0.377). In contrast to significant site- wise variation in density, there was no significant difference in benthic diversity across the sites and no significant seasonal variation of benthic density and diversity from the statistical point of view.

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.

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.

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.

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.

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.

The aim of this study is to determine the amount of quantitative and qualitative changes in groundwater in the Sarvestan plain in south of Fars province, which is one of the critical plains in Iran in terms of water resources. In this research, zoning maps of electrical conductivity of water in GIS were prepared and various hydrochemical diagrams were illustrated. Different quality parameters of water resources were compared according to the statistical data collected and the experiments performed at the beginning of the 8-year period of the research. Chemical analysis of water samples shows that the groundwater type of most of the studied wells at the beginning of the period (2013) has changed from Ca-Cl and Mg-Cl types to Na-Cl type at end of the time period (2020). Determining the trend of chemical changes shows that the diversity of water samples in terms of anions and cations in water with increasing salinity at the end of the period is less than the variety of samples at the beginning of the period. According to the results of chemical experiments, evaporation, crystallization, and weathering of rocks are the factors that control the composition of groundwater in the study area. This study shows increasing the salinity of groundwater in addition to decreasing precipitation and high water use for agricultural application, due to the type of geological formations, especially the presence of salt domes at groundwater inlets to the plain on the east side of the study area.

The ability of fungi to act as bio-sorbent had been extensively evaluated and has shown excellent metal sequestering ability for heavy metals such as cadmium, copper, zinc, lead, iron, nickel, radium, thorium, and uranium from aqueous solution. In the present study, tolerance, removal efficiency and adsorption capacity of hexavalent chromium using isolated fungal strains were analysed. Total nine fungal isolates were obtained from organic pollutants and metals contaminated Gujarat Industrial Development Cooperation sites. Filamentous fungi isolated belonged to Aspergillus spp., Rhizopus spp., Trichoderma spp., and Penicillium spp. Chromium sorption experiments using isolated fungal strains were carried out to check adsorption capacity and adsorption intensity. At higher chromium concentration, removal efficiency and adsorption capacity were observed in the order of Aspergills candidus > Aspergillus ochraceus > Aspergillus flavus > Rhizopus spp. > Trichoderma spp. A. candidus showed higher adsorption capacity, 5.49mg/g with 98.75% chromium removal efficiency at 150ppm of hexavalent chromium. The observed RL value for Langmuir isotherm for all the three concentrations was less than 1, depicting favourable sorption and in Freundlich isotherm, the value of 1/n exceeds more than 1 showing co-operative or similar type of adsorption.

Atmospheric models today represent all significant aerosol components. Atmospheric aerosols play an important role in the air, globally through their action on the Earth's radiation balance and locally through their effects on health in heavily polluted areas, they vary considerably in their properties that affect the way they absorb and disperse radiation, and they can thus have a cooling or warming effect, they impact on the formation and life of clouds is one example. Among the main sectors of activity releasing emissions of PM10 (fine particles with a diameter of less than 10 µm) and a diameter of less than 2.5 µm (PM2.5) is the industrial sector, in particular the extraction industry of building materials. The aerosols emitted by this type of industry are composed mainly of a mixture of dust, sulphates, carbon black and nitrates, is clearly perceptible in many continental regions of the northern hemisphere. Improvements in in situ, satellite and surface measurements are needed. However, the mechanisms by which aerosols interact with the environment are extremely complex and still poorly understood. This study is based on satellite atmospheric models to have spatiotemporal variability of concentrations of fine particles smaller than 10 µm in diameter (PM10) and smaller than 2.5 µm in diameter (PM2.5) at the level of the western Rif part of Morocco, home to a large number of extraction quarries and thus offering a high-resolution particle capture system (PM10 and PM2.5).

Mining activities are generally known to enhance the concentration of primordial radionuclides in the environment thereby contributing immensely to human exposure to ionizing radiation of terrestrial origin. Thus, the abandoned Tin and Cassiterite mining site in Oyun, Kwara State, Nigeria, is believed to cause radiological implications on local residents.  Assessment of radon concentration in surface water from the study area was carried out using RAD7-Active Electronic detector big bottle system. In order to ascertain the risk or hazard incurable in consuming such water, 12 samples were analysed and used in the estimation of annual effective dose of radon. The measured maximum and minimum radon concentrations were found to be 44.95 and 21.03 Bq/L with average of 35.86 Bq/L. These values are quite greater than the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) recommended limits of 11.1.Bq/L. The estimated total effective dose (AEDEtotal) was found to be within the range of 206.52 and 441.41 μSvy-1, and an average of 352.20 μSvy-1 for Adults, 283.30 and 605.47 μSvy-1, and average of 483.10 μSvy-1 for Children, and finally, 321.70 and 687.47 μSvy-1 with average of 548.64 μSvy-1 for Infants, respectively. These values were higher than the recommended limit of 100 µSvy-1 and 200 µSvy-1 for adult and children respectively. Furthermore, worries should be noted about the probabilistic cumulative effect on the consumers of such water if the ingestion is for an extended period of time.

Global fire cases in recent years and their vast damages are vivid reasons to study the wildfires more deeply. A 25-year period natural wildfire database and a wide array of environmental variables are used in this study to develop an artificial neural network model with the aim of predicting potential fire spots. This study focuses on non-human reasons of wildfires (natural) to compute global warming effects on wildfires. Among the environmental variables, this study shows the significance of temperature for predicting wildfire cases while other parameters are presented in a next study. The study area of this study includes all natural forest fire cases in United States from 1992 to 2015. The data of eight days including the day fire occurred and 7 previous days are used as input to the model to forecast fire occurrence probability of that day. The climatic inputs are extracted from ECMWF. The inputs of the model are temperature at 2 meter above surface, relative humidity, total pressure, evaporation, volumetric soil water layer, snow melt, Keetch–Byram drought index, total precipitation, wind speed, and NDVI. The results show there is a transient temperature span for each forest type which acts like a threshold to predict fire occurrence. In temperate forests, a 0.1-degree Celsius increase in temperature relative to 7-day average temperature before a fire occurrence results in prediction model output of greater than 0.8 for 4.75% of fire forest cases. In Boreal forests, the model output for temperature increase of less than 1 degree relative to past 7-day average temperature represents no chance of wildfire. But the non-zero fire forest starts at 2 degrees increase of temperature which ends to 2.62% of fire forest cases with model output of larger than 0.8. It is concluded that other variables except temperature are more determinant to predict wildfires in temperate forests rather than in boreal forests.

Atmospheric aerosols are very crucial from air pollution and health perspective as well as for regional and global climate. This paper attempts to summarize the aerosol loading and their properties such as Aerosol Optical Depth (AOD), Single Scattering Albedo (SSA), Angstrom exponent, and Radiative forcing, over India. All the above mentioned parameters have shown significant variability with change in the site and season. From various studies it was observed that AOD is relatively higher over Northern part of India as compared to Southern and Eastern part. Generally, lower values of SSA were observed over all sites during winter and post-monsoon seasons which indicates the dominance of absorbing type aerosol during these seasons. Also the ARF within atmosphere showed comparatively higher values during November-December and lower value during August and September all over the India. The current state of knowledge about aerosol sources, interactions and their effects on environment is limited because of its complexity. Therefore, more focused research in needed to understand the aerosol’s role in climatic phenomenon.

A large anthropogenic source of mercury pollution is mercury-dependent artisanal and small-scale gold mining (ASGM). Thabeikkyin Township is a small-scale gold mining township located in Pyin Oo Lwin District in the Mandalay Region, Myanmar. The villages of Thabeikkyin Township engage in gold ore crushing, screening, refining, and other mining activities for a living. Miners in this area commonly use mercury for gold recovery by heating amalgam at their homes, gold shops, on the street, and near the riverbank. The evaporated mercury is released into the atmosphere during the heating process and then transported and deposited in the surrounding environments, resulting in the mercury pollution of air, water, soil, etc. To assess atmospheric mercury pollution, a preliminary study on the environmental mercury contamination from ASGM was conducted in Thabeikkyin Township. High mercury concentrations were observed in plant samples collected near the refining sites, ranging 0.33–6.51 ug/g, compared with 0.02 ug/g in Wet Thay Village, where no mercury use was reported. Correlation coefficients between Hg and other heavy metals showed that no heavy metal concentration significantly correlated with that of Hg. The results indicated that the atmospheric environment in the ASGM area of Thabeikkyin Township was contaminated with mercury originating from ASGM, which could very likely deteriorate the health of surrounding residents.

The increased consumption of fossil fuels provokes high levels of carbon dioxide (CO2) emissions, which give rise to serious environmental issues. Accordingly, designing and utilizing new classes of materials, such as Schiff bases, to capture CO2 gained significant attention from researchers worldwide. In the present work, two Schiff bases were synthesized and examined as storage materials for carbon dioxide gas. The prepared compounds were obtained by reacting trimethoprim with two aldehydes severally (benzaldehyde and parabromobenzaldehyde) in boiling methanol. The surface morphology of the compounds was investigated via field emission scanning electron microscopy (FESEM). The Brunauer-Emmett-Teller (BET) test showed that Schiff bases 1 and 2 have surface areas of 17.993 and 2.732 m2/g, pore volumes of 0.008 and 0.005 cm3/g, and pore diameters of 17.02 and 74.89 nm, respectively. Reasonable uptake values of CO2 (31.36 cm3/g, 6.2 wt%) and (25.30 cm3/g, 5.0 wt%) were achieved by the prepared Schiff bases 1 and 2, respectively, at 313 K temperature and 40 bars pressure.

Saraca asoca bark has long been used in traditional Indian medicine. Considering its low cost and non-toxic nature, it can find application as a biosorbent. This article explores the application of Saraca asoca bark powder (SABP) for biosorption of hexavalent chromium. Various analytical techniques including Field emission scanning electron microscope (FESEM) attached with energy dispersive spectrometer (EDS), Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHpzc) were adopted in order to identify the physico-chemical features of SABP. Factors such as pH (2-8), contact time (for 3 hours), initial Cr (VI) concentration (10 – 250 mg/l) and temperature (15 - 35°C) were examined for their influence on Cr (VI) biosorption via batch studies. Biosorption data clearly followed Redlich-Peterson isotherm model as compared to Langmuir and Freundlich models. The Langmuir monolayer adsorption capacities (Qm) at 15, 25 and 35°C were 123.4, 125.0 and 175.4 mg/g respectively. Biosorption followed pseudo-second-order kinetics and the mechanism of diffusion was governed by both surface sorption and pore diffusion as demonstrated by the plot for Intraparticle diffusion model and the pore diffusion coefficient (Dp~10-9 cm2/s). The nature of biosorption was found to be spontaneous and endothermic as reflected through various thermodynamic parameters such as the free energy change (ΔG = -3.0 to -3.7 kJ/mol), entropy change (ΔS = 37.8 J/K/mol) and enthalpy change (ΔH = 7.9 kJ/mol). The study recommends that SABP may be utilized as a potential biosorbent for Cr(VI) ions.

In this work, we study  the short-term dynamics of the Surface  Air Temperature (SAT) using data obtained  from a  meteorological station in Bogotá from 2009 to 2019  and using  time series.  The data that we used correspond to the  monthly mean of the historical registers of SAT and three  pollutants. A descriptive analysis of  the data follows. Then, some predictions are obtained from two different approaches:  (i) a univariate analysis of SAT through a  SARIMA model, which shows a good fit; and  (ii) a multivariate analysis of SAT and  pollutants  using a SVAR model. Suitable transformations were first applied on the original dataset to work with stationary time series. Subsequently, A SARIMA model and a VAR(2) with its associated SVAR model are estimated. Furthermore, we obtain one-year forecasts for the logarithm of SAT in both models. Our forecasts simulate the natural fluctuation of SAT, presenting peaks and valleys in months when SAT is high and low, respectively. The SVAR model allows us to identify certain shocks that affect the instant relationships among variables. These relations were studied by the impulse-response function and the VAR model variance decomposition. Although the statistical methods used in this study are classical, they continue being widely used in the environmental field, presenting god fits, and the results obtained in this study are consistent with  environmental theories.

Organophosphates are one of the most common pesticides in the world. Among them, one can find malathion that is classified as carcinogenesis, and, as a result, should be appropriately removed since it is highly consumed and possesses a lot of pathogenicity. So far, several processes have been used to remove malathion from aqueous media. The present study investigates its removal by means of Fe3O4 iron oxide nanoparticles. Based on experimental-laboratory studies, using the Response Surface Methodology (RSM), the impact of independent variables such as pH, iron oxide nanoparticle concentration, and contact time on malathion removal efficiency have been investigated. Results show that the pH of the solution is the most important and effective parameter in the process. Optimal conditions of malathion removal based on the appropriate model, obtained from RSM, include 0.4 g/L iron oxide nanoparticles, pH of about 5 (acidic conditions), and contact time of about 1 h with ultraviolet radiation being equal to 82% malathion removal. The process, used in this study, can remove malathion from aqueous solutions according to the so-called conditions, and changing the laboratory conditions can effectively remove it. This process can also be recommended as an economic and scientific method to remove malathion from drinking water.

In this work, Fe3O4-SiO2 nanoparticles were synthesized, characterized, and applied as adsorbent material to remove methyl blue stain from an aqueous solution. The prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and Brunauer–Emmett–Teller (BET) to determine the physical surface properties and correlate them to the adsorption efficiency. In addition, this study investigated the influence of several parameters on the removal percentage and adsorption capacity. Specifically, this study investigated the impact of changing the following parameters: pH (1 – 8), agitation speed (Uspeed; 100 - 350 rpm), initial methyl blue (MB) concentration (1 - 100 mg/L), adsorbent dose (0.05 to 0.15 g), and contact time (10 - 100 min). The characterization study reveals that the prepared material has an excellent surface area (385 ± 5 m2/g) and pore volume (0.31 cm3/g) which enhances the adsorption capacity. In addition, the prepared material showed excellent efficiency where the removal percentage reached 99.0±1% at the optimal operating conditions and the maximum adsorption capacity was 40 mg/g. This study delivers a full elucidation of the adsorption of MB dye by Fe3O4-SiO2 NPs which considers a promising inexpensive adsorbent. It also delivers important insight information about the adsorption process and the influence of each parameter, which fill the lack in this field.

Cities in developing countries like Shiraz in Iran face significant challenges due to a lack of an integrated solid waste management system. Climate change, soil, and water pollution are examples of environmental issues caused by improper Municipal Solid Waste Management Systems (MSWMS) in developing countries. The aim of this study is to find solutions for these environmental problems based on the experiences of developed countries. The data was collected using several methods such as visual observations, studying accessible documents of the current situation of the MSWMS in Shiraz, and participating in an interview with engineers the 'Shiraz Municipality Waste Management Organization' (SMWMO).  Results present the current functional elements of MSWMS in Shiraz, Shiraz waste diversion rate (0.22), and its Zero Waste Index (.015). Moreover, the results present some recommendations to find a way to transform cities like Shiraz into zero-waste cities. Results indicate that establishing zero-waste policies, legal frameworks, and financial strategies as well as convincing private sector involvements in installing waste-to-energy facilities and a proper sanitary landfill to move the city toward optimum recycling and zero landfilling in addition to reducing consumption and maximizing diversion rate and finally sustainable development by the cooperation of government, NGOs and media programs would solve many problems of the MSWMS and would solve environmental issues in many cities.

Aerosols are tiny particles (liquid or solid) suspended in the atmosphere. They play a significant rolein climate dynamics directly or indirectly. Aerosol Optical Depth (AOD) and Angstrom Exponent(AE) are significant parameters to study the concentration and size or type of aerosol over an area,respectively. In this article, we utilized three years of AOD and AE parameters derived from moderateresolution imaging spectroradiometer (MODIS) satellite during the period January, 2013 to December,2015 over Ethiopia. In order to study the spatiotemporal pattern of aerosols, we choose three areas(Debretabour, Gojjam and Addis Ababa) over Ethiopian highlands, which are representative of nonindustrial, agricultural and industrial areas respectively. Further we compare continental aerosols withmarine aerosols from Djibouti. Our results clearly depicts the aerosol distribution over Ethiopia ishighly variable spatially and temporally. The results indicates that the urban and biomass aerosols aredominate over Addis Ababa, and Gojjam respectively, whereas dust and biomass aerosols are presentover Debretabour, while Djibouti is loaded by sea spray aerosols. The seasonal variability of AOD isfound to be maximum during the kiremt (summer) and minimum during bega (winter) over all areas(continental and marine).

Industrial sector is understood to be one of the major offenders in polluting environment particularlywater among others. Sugar industry is one among the agro-based industry releasing high organicpollutants rich in BOD. Though conventional treatment methods have been employed in treating sugarindustry effluents at varied degrees, they come with their own setbacks. In this direction naturalcoagulants are explored and evaluated for their potential and efficiency towards treating sugar industryeffluents. The process of coagulation and flocculation removes impurities precisely colloidalimpurities through the phenomenon of destabilization, bridging and sweep coagulation. In order tohave an effective treatment factors governing coagulation are to be optimized to determine the dose,pH, mixing time etc. The prime objective of the present study is to characterize the sugar industryeffluents, test the efficiency of both chemical and natural coagulants to treat these effluents and bringout a comparison and potential of natural coagulants with that of chemical coagulants. Jar testapparatus was employed all coagulation studies and the results were promising with reduction inparameters like colour (99.28%), electrical conductivity (60.39%), turbidity (97.67%), chloride(69.23%) and total dissolved solids (60.42%) highest by ferric chloride followed by the naturalcoagulants. The findings of the study suggest that the lowest dose of 0.25g/l was optimum to removethe physico-chemical parameters both by chemical and natural coagulants and since natural coagulantswere equally competent with chemical coagulants these can be substituted towards achieving greentreatment options.

Air pollution is a global issue and meteorological factors play an important role in its transportationand regional concentration. The current research is aimed to analyse the variations in meteorologicalparameters in a seasonal and geographical location context in the Jiangsu province of China, and itscorrelation with the six criteria air pollutants, and air quality index (AQI). The present analysis willsupplement the limited understanding on the relation between the regions prevalent climatic conditionsand atmospheric pollution. The meteorological data analysis showed Suzhou city located in thesouthern region of the Jiangsu province with high average temperature, relative humidity, and rainfall.Maximum values of temperature, UV index, sunshine, relative humidity, and rainfall occurred duringsummer, while air pressure in winter. High values of all meteorological parameters occurred in thenorthern and southern region of the province. The data correlation study revealed AQI to havenegative correlation with most meteorological parameters, and positive correlation with air pressure inall cities.