Influence of multi-industrial activities on trace metal contamination: an approach towards surface water body in the vicinity of Dhaka Export Processing Zone (DEPZ)

Industrial wastewater discharged into aquatic ecosystems either directly or because of inadequate treatment of process water can increase the concentrations of pollutants such as toxic metals and others, and subsequently deteriorate water quality, environmental ecology and human health in the Dhaka Export Processing Zone (DEPZ), the largest industrial belt of 6-EPZ in Bangladesh. Therefore, in order to monitor the contamination levels, this study collected water samples from composite effluent points inside DEPZ and the surrounding surface water body connected to effluent disposal sites and determined the environmental hazards by chemical analysis and statistical approach. The water samples were analysed by inductively coupled plasma mass spectrometry to determine 12 trace metals such as As, Ag, Cr, Co, Cu, Li, Ni, Pb, Se, Sr, V and Zn in order to assess the influence of multi-industrial activities on metal concentrations. The composite effluents and surface waters from lagoons were characterized by a strong colour and high concentrations of biochemical oxygen demand, chemical oxygen demand, electrical conductivity, pH, total alkalinity, total hardness, total organic carbon, Turb., Cl(-), total suspended solids and total dissolved solids, which were above the limit of Bangladesh industrial effluent standards, but dissolved oxygen concentration was lower than the standard value. The measurement of skewness and kurtosis values showed asymmetric and abnormal distribution of the elements in the respective phases. The mean trend of variation was found in a decreasing order: Zn > Cu > Sr > Pb > Ni > Cr > Li > Co > V > Se > As > Ag in composite industrial effluents and Zn > Cu > Sr > Pb > Ni > Cr > Li > V > As > Ag > Co > Se in surface waters near the DEPZ. The strong correlations between effluent and surface water metal contents indicate that industrial wastewaters discharged from DEPZ have a strong influence on the contamination of the surrounding water bodies by toxic metals. The average contamination factors were reported to be 0.70-96.57 and 2.85-1,462 for industrial effluents and surface waters, respectively. The results reveal that the surface water in the area is highly contaminated with very high concentrations of some heavy/toxic metals like Zn, Pb, Cu, Ni and Cr; their average contamination factors are 1,460, 860, 136, 74.71 and 4.9, respectively. The concentrations of the metals in effluent and surface water were much higher than the permissible limits for drinking water and the world average concentrations in surface water. Therefore, the discharged effluent and surface water may create health hazards especially for people working and living inside and in the surrounding area of DEPZ.     

Transformation of nitrogen dioxide into ozone and prediction of ozone concentrations using multiple linear regression techniques

Analysis and forecasting of air quality parameters are important topics of atmospheric and environmental research today due to the health impact caused by air pollution. This study examines transformation of nitrogen dioxide (NO₂) into ozone (O₃) at urban environment using time series plot. Data on the concentration of environmental pollutants and meteorological variables were employed to predict the concentration of O₃ in the atmosphere. Possibility of employing multiple linear regression models as a tool for prediction of O₃ concentration was tested. Results indicated that the presence of NO₂ and sunshine influence the concentration of O₃ in Malaysia. The influence of the previous hour ozone on the next hour concentrations was also demonstrated.     

Abundances, distribution, and sources of trace metals in Nakaumi–Honjo coastal lagoon sediments, Japan

Bottom sediments from Nakaumi Lagoon and the Honjo Area in southwest Japan were analyzed to determine their geochemical compositions and to assess potential impacts by comparison with sediment quality guidelines. Present-day water quality was also assessed. Results showed that the water quality of Nakaumi Lagoon and the Honjo area contrasts between their upper and lower parts. Average abundances of As, Pb, Zn, Cu, Ni, and Cr in the Nakaumi sediments were 12, 25, 135, 32, 21, and 46 ppm, respectively, compared to 10, 24, 110, 26, 20, and 38 ppm in the Honjo area. All averages are greater than those of the upper continental crust. The elevated metal concentrations are probably related to the fine-grained nature of the sediments, reducing bottom conditions produced by abundant organic matter and possibly minor non-point anthropogenic sources. Trace metal contents are strongly correlated with Fe₂O₃, suggesting that Fe oxides play a role in controlling abundances. Metal concentrations exceed the NYSDEC lowest effect level and CCME interim sediment quality guidelines that indicate moderate impact on aquatic organisms. Average abundances of As and Zn are comparable to the Coastal Ocean Sediment Database threshold, whereas maximum concentrations exceed that value, indicating that the concentrations of these metals are potentially toxic. These enrichments suggest that regular monitoring may be desirable even where no point sources of metal pollution exist.     

Determination of heavy metals in bee honey with connected and not connected metal wires using inductively coupled plasma atomic emission spectrometry (ICP–AES)

Two honey samples are taken from two parts of the same honeycomb: one that contacts to the surface of the wire and the other taken from the surface that does not contact the wires. Heavy metal contents of these two samples were determined by inductively coupled plasma atomic emission spectrometry). The Mo, Cd, Cr, Fe, Mn, Ni and Zn contents of the honey in contact with wire is higher when compared to the other. Especially, Fe and Zn contents of honey in contact with wire is much higher than the non-contact one. These values are, respectively, 190.21 and 112.76 ppm. Besides, Ni content of honey in contact with wire is approximately 50% higher.     

Switching behaviors toward green brands: evidence from emerging economy

The aim of the current research was to recognize consumer attitude gap toward green brand by studying role of green consumer value and green brand equity toward the switching intention and purchase intention of consumers toward green brands. The current research employed quantitative research design and collected data through questionnaire from 331 respondents. The PLS-structural equation modeling was employed to analyze the structured relationships. The findings suggest green customer value is product of the three important factors namely green brand experiential risk, green brand experiential quality and green brand experience. Hence, these act as the main drivers of switching consumer behavioral intention toward the green products through consumer green brand equity. The research attempts to study the attitude–behavior gap in the green marketing literature by investigating the role which includes, green brand experiential risk, green brand experiential quality and green brand experience on customer value leading to green brand equity. The research provide an in-depth understating of attitude–behavior gaps and role of green customer value and brand equity that plays vital role in marketing campaigns and policy making to increase purchase intention of green eco-conscious products.

     

Contaminant transport in groundwater in the presence of colloids and bacteria: Model development and verification

Colloids and bacteria (microorganisms) naturally exist in groundwater aquifers and can significantly impact contaminant migration rates. A conceptual model is first developed to account for the different physiochemical and biological processes, reaction kinetics, and different transport mechanisms of the combined system (contaminant–colloids–bacteria). All three constituents are assumed to be reactive with the reactions taking place between each constituent and the porous medium and also among the different constituents. A general linear kinetic reaction model is assumed for all reactive processes considered. The mathematical model is represented by fourteen coupled partial differential equations describing mass balance and reaction processes. Two of these equations describe colloid movement and reactions with the porous medium, four equations describe bacterial movement and reactions with colloids and the porous medium, and the remaining eight equations describe contaminant movement and its reactions with bacteria, colloids, and the porous medium. The mass balance equations are numerically solved for two-dimensional groundwater systems using a third-order, total variance-diminishing scheme (TVD) for the advection terms. Due to the complex coupling of the equations, they are solved iteratively each time step until a convergence criterion is met. The model is tested against experimental data and the results are favorable.     

Dual Function of Cellulose Triacetate–Graft–Polymethacrylic Acid Films for Dyes Removal and for High-Dose Radiation Dosimetry

Graft copolymerization of methacrylic acid (MAc) onto cellulose triacetate (CTA) films was conducted by gamma rays. The grafting conditions were optimized. The structure of grafted CTA films was characterized by Fourier transform infra red–attenuated total reflection, scanning electron microscopy, thermal gravimetric analysis, CHNS/O microanalyzer and, surface area and porosity analyzer. The grafted CTA films were exploited in adsorption of ethyl violet (EV) and phenol red (PR) dyes. The adsorption capacity of the grafted CTA films was investigated at various variables. The adsorption isotherms and kinetic study were examined. Further, the dyed grafted CTA films were used in measurements of high dose radiation. The results indicate that the useful dose range extents up to 440 and 300 kGy for EV and PR, respectively. The effects of relative humidity during irradiation, shelf-life, pre- and post-irradiation storage in dark and indirect daylight conditions on dosimeters performance were investigated.     

Machine learning and computational chemistry to improve biochar fertilizers: a review

Traditional fertilizers are highly inefficient, with a major loss of nutrients and associated pollution. Alternatively, biochar loaded with phosphorous is a sustainable fertilizer that improves soil structure, stores carbon in soils, and provides plant nutrients in the long run, yet most biochars are not optimal because mechanisms ruling biochar properties are poorly known. This issue can be solved by recent developments in machine learning and computational chemistry. Here we review phosphorus-loaded biochar with emphasis on computational chemistry, machine learning, organic acids, drawbacks of classical fertilizers, biochar production, phosphorus loading, and mechanisms of phosphorous release. Modeling techniques allow for deciphering the influence of individual variables on biochar, employing various supervised learning models tailored to different biochar types. Computational chemistry provides knowledge on factors that control phosphorus binding, e.g., the type of phosphorus compound, soil constituents, mineral surfaces, binding motifs, water, solution pH, and redox potential. Phosphorus release from biochar is controlled by coexisting anions, pH, adsorbent dosage, initial phosphorus concentration, and temperature. Pyrolysis temperatures below 600 °C enhance functional group retention, while temperatures below 450 °C increase plant-available phosphorus. Lower pH values promote phosphorus release, while higher pH values hinder it. Physical modifications, such as increasing surface area and pore volume, can maximize the adsorption capacity of phosphorus-loaded biochar. Furthermore, the type of organic acid affects phosphorus release, with low molecular weight organic acids being advantageous for soil utilization. Lastly, biochar-based fertilizers release nutrients 2–4 times slower than conventional fertilizers.

     

Impact assessment of urban development patterns on land surface temperature by using remote sensing techniques: a case study of Lahore,Faisalabad and Multan district

Environmental Science and Pollution Research - Urban Heat Island (UHI) is related to the theory of higher atmosphere and surface temperature taking place in the city area as compared to the nearby...     

Using GIS tools to detect the land use/land cover changes during forty years in Lodhran District of Pakistan

Environmental Science and Pollution Research - Land use/land cover (LULC) change has serious implications for environment as LULC is directly related to land degradation over a period of time and...