Pathways of photochemical degradation of a cardiovascular drug verapamil under conditions relevant to natural waters and the toxicity of the photoproducts to Daphnia magna were investigated. Photodegradation was shown to proceed via photocatalysed mechanism. Two main photodegradation pathways were recognised: the first leading to hydroxylation at the methylamino position followed by splitting of verapamil molecule into two fragments, and the second providing the main active metabolite of verapamil, norverapamil, and a series of norverapamil isomers, followed again by their splitting at the amino group position. Twenty-two products of photodegradation were identified. Toxicity assays in sublethal concentrations of the parental drug, of the photoproduct mixture, and of norverapamil revealed no direct negative response in Daphnia magna to verapamil. On the other hand, photochemical products significantly lowered the number of juveniles, number of clutches, and body size of Daphnia. The exposition of Daphnia to norverapamil showed the same but even more pronounced effects than its exposition to the mixture of photoproducts, which leads to the conclusion that norverapamil is mainly responsible for the toxicity of photoproduct mixture and represents a noteworthy threat to aquatic invertebrates.

Climate change issues and adaptation strategies have drawn much attention from many fields in recent years. Taiwan, an island state, is deeply threatened by the multiple threats posed by climate change. However, different urban and rural areas have numerous adaptation approaches due to their differences in vulnerability. In Taipei City (urban), its biophysical vulnerability is mainly affected by flooded areas and high flood depths caused by landslides and heavy rains. Its social vulnerability is affected by economic development, high household assets, and population concentration. In Yunlin County (rural), its biophysical vulnerability is also affected by flooded areas and high flood depths caused by heavy rains. Its social vulnerability is affected by the elderly living alone, low household assets, and low healthcare. In order to propose appropriate adaptation strategies of urban and rural areas under different vulnerabilities, this study uses an overlapping method to examine the relationship between the integrated vulnerability (biophysical and social) of Taipei and Yunlin along with the ecological footprint (EF), a measurement of human demands for resources and ecological services. This study reviews the literature and uses Taiwan’s NCDR (National Science and Technology Center for Disaster Reduction) data to analyze the biophysical vulnerability and the social vulnerability and further calculate the integrated vulnerability. In this study, questionnaire surveys were conducted. In Taipei, 446 valid questionnaires were collected, while 393 were collected in Yunlin. The results show that personal EF in Taipei is higher than that in Yunlin. In the end, this study elucidates the relationship between integrated vulnerability and personal EF of Taipei and Yunlin. Four types of risk areas in urban Taipei and rural Yunlin are sorted out (high vulnerability/high EF, high vulnerability/low EF, low vulnerability/high EF, and low vulnerability/low EF). The empirical results can be adopted by local governments, communities, and NGOs to establish appropriate strategies for mitigation and adaptation in the different risk areas.

Climate scenarios for future global warming expect the enhancement of the hydrological cycle during the twenty-first century. In particular, accurate simulation of water content in the soil depends not only on the correct determination of the percentages of each component in the water balance but also on the measured biophysical properties of the soil available. One of the greatest man-made environmental disasters in history is the destruction of the Aral Sea which is heavily polluted. Possible scenarios have been formulated, to transfer water from the Siberian rivers to Central Asia and to limit the unsustainable extension of irrigation in this region. A new scenario proposed in this paper is partly based on the use of Caspian water evaporators located on the eastern coast of the Caspian Sea. The implementation of this scenario allows the rescue of the Aral Sea and the normalization of water balance in Central Asia. The results of the calculations show that the Aral Sea can be restored over the next 90–240 years depending on these versions. If the anthropogenic outflow of river water is further reduced by 10%, the Aral Sea will be restored for about 90 years. Finally, possible versions of the water recovery scenario are discussed and evaluated and compared with other examples such as Lake Eyre in Australia, Lake Sevan in Armenia, and Lake Chad in central Africa.

Steelmaking slag, a by-product of the steel-refining process, could be used for removing boron excess from irrigation natural and waste waters, due to its strongly alkaline reaction. The objectives of this study were to: (a) establish the optimum conditions (external solution/adsorbent ratio, equilibration time) of boron adsorption by the slag, (b) assess the slag’s capacity to adsorb boron, and (c) study boron desorption from the slag with time. Boron adsorption increased with the increase of the external solution/adsorbent ratio up to the ratio of 200:1. Although, almost 40% of boron was adsorbed within the first hour of equilibration period, the adsorption gradually increased until the 72 h. The Langmuir adsorption maximum for boron was 145 mg g⁻¹, considerably higher than other adsorbents, like fly ash, calcite, and magnesia. At boron initial concentrations lower than 6 mg L⁻¹, slag removed 55% of boron and reduced it below the permissible levels for irrigation waters (< 4 mg L⁻¹) for most crops. The pH of the equilibrium solution was 10.3 ± 0.8 and dropped to acceptable levels for irrigation waters (< 8.5), after contact with atmosphere for 1 week. Almost 25% of boron was released from samples of boron-laden slag during the first hour of desorption. Consequently, steelmaking slag can be used effectively for removing boron excess from irrigation waters. However, attention should be given to the pH of the slag-treated waters. Furthermore, the disposal of boron-laden slag to soils should be practiced with caution to avoid possible boron phytotoxicity risk.

Post-combustion flue gas desulfurization and denitrification technologies are essential in achieving the full compliance of fine particulate matter (PM₂.₅, aerodynamic diameter less than 2.5 μm) air quality standards by 2030 in China as sulfur dioxide (SO₂) and nitrogen oxides (NOX) are the main precursors of PM₂.₅. Some studies have addressed the performance evaluation of desulfurization technology, but none included the water-soluble ions (sulfate (SO₄²⁻), nitrate (NO₃⁻), etc.) as an indicator nor accounted for uncertainty involved. In this study, we present a multilevel fuzzy method that integrates the analytic hierarchy process with fuzzy theory, defines SO₄²⁻concentration as a new environmental indicator, and is supplemented with an uncertainly analysis and apply the method for the techno-economic and environmental evaluation of desulfurization and denitrification technologies in six typical enterprises (including two power plants and three industrial production plants and a waste incineration plant) in Chengdu, China. The evaluation shows that first, the fluctuating desulfurization rate and the dosage leads to changed ranking of the economic and technical secondary evaluation results, with the overall comprehensive evaluation ranks unchanged. Second, from the perspective of environmental protection agency and the public, if the environmental indicators are empowered, the lower the SO₄²⁻concentration of an enterprise, the better its evaluation ranking will be and vice versa. Third, if we re-empower from the perspective of the enterprise, under the condition that the technical feasibility is met and the environmental indicators are basically up to standard, the low-cost removing process is more likely to be the tendency of the enterprise. In summary, the findings of the study have led to the conclusions that (1) for the power industry, the integration of desulfurization, denitrification, and dedusting technologies should be promoted rigorously; (2) the non-power industry should continue the end-of-pipe treatment and environmental protection regulatory policies of the power industry; and (3) the energy industry structure should be optimized with enhanced end-of-pipe control technologies to achieve deep reduction of air pollutants.

Mechanically robust Fe₃O₄/porous carbon/diatomite composite monolith was prepared from waste corrugated cardboard box and diatomite via slurrying in FeCl₃ solution, dewatering, molding, and carbonization at 600 °C. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (SEM), N₂-adsorption/desorption, Raman spectroscopy, and ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy. The water wettability, photothermal conversion property, and solar steam generation performance of the products were also evaluated. Results showed that the presence of FeCl₃ led to the formation of more pores and magnetic Fe₃O₄ crystallites, while diatomite provided good hydrophilicity for the composite. The product exhibited light absorption above 65% within the wavelength ranging from 200 to1974 nm, and its surface temperature eventually increased by 30 °C under 0.25 sun irradiation due to photothermal effect. Moreover, solar steam yield under 0.25 sun irradiation for 3600 s was improved by 67% with the presence of the monolithic composite because of the occurrence of interfacial solar steam generation and heat transfer from the composite acted as a heat island.

The broad purpose of this study is to empirically explore the impact of globalization and financial development on environmental pollution by carbon (CO₂) emissions in the six Middle East and North Africa (MENA) countries using balanced panel data from 1971 to 2015. We also aimed to test the legitimacy of the environmental Kuznets curve (EKC) hypothesis for this region. The fixed-effects approach preferred by the Hausman specification test is used to estimate the empirical model, and the feasible generalized least squares (F.G.L.S.) estimator is employed to cope with any issue of heteroscedasticity and serial correlation. This study found that globalization and financial development have adverse and significant effects on environmental degradation and affirm the legitimacy of the EKC hypothesis for these countries. The finding of this study suggests that the governments of MENA countries should design and implement appropriate policies for strengthening the renewable sources of energy like wind, solar, bio-fuel, and thermal to decrease CO₂ emissions and boost sustainable economic development. The policymakers should focus on the efficiency of institutions and enhancement of energy-saving projects in this region.

Worldwide, the requirement of electrical energy has increased with an increase in population. Thus, there is a need to develop an alternative source of sustainable energy, such as microbial fuel cell (MFC). MFC is a better option of energy generation and can provide a renewable resource which utilizes wastewater into power by the help of microorganisms. MFC is one of the advanced methods for treating wastewater and simultaneously producing current and voltage. Dual-chambered MFC was prepared using two plastic boxes (500 ml) by using wastewater as an anolyte. Different types of mediators are used in MFC including methylene blue, potassium ferricyanide, and EDTA to facilitate and higher the efficiency of electron transfer from the MFC to the electrode. Maximum OCV and current output of sample 1 (Budha Talab pond water) were 0.86 V and 75.1 mA and of sample 2 (Jaypee cement plant) were 1.42 V and 122 mA. The maximum current output of sample 3 (sugar industry, sewage waste, NIT canteen) was 1.3 V. Various physiochemical parameters such as dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) were analyzed which affect the power output. The obtained result concluded that wastewater should be feed at a certain time interval to avoid the loss of substrate for organisms in the anodic chamber which lead to the death of the microorganism. Among all, sugar industry wastewater has a high potential for power generation as their physiochemical results are suitable for better power output.

Mercury (Hg), the environmental toxicant, is present in the soil, water, and air as it is substantially distributed throughout the environment. Being extremely toxic even at low concentration, its remediation is utterly important. Therefore, it is necessary to detoxify the contaminant within the acceptable limits before threatening the environment. Although various conventional methods are being used, irrespective of high cost, it produces intermediate toxic by-product too. Biological methods are eco-friendly, clean, greener, and safer for the remediation of heavy metals corresponding to the conventional remediation due to their economic and high-tech constraints. Bioremediation is now being used for Hg (II) removal, which involves biosorption and bioaccumulation mechanisms or both, also mercuric ion reductase, exopolysaccharide play significant role in detoxification of mercury by acting a potential instrument for the remediation of heavy metals. In this review paper, we shed light on problems caused by mercury pollution, mercury cycle, and its global scenario and detoxification approaches by biological methods and result found in the literature.

The main objective of this study was to characterize the Giardia duodenalis isolates from Iranian patients in Fars Province, south of Iran by biochemical and molecular methods. Fifteen mass cultivated of G. duodenalis isolates in modified TYI-S-33 medium were analyzed using isoenzyme electrophoresis and PCR genotyping. Polyacrylamide gel electrophoresis (PAGE) of five different enzyme systems was used to characterize isolates: (i) glucose-6-phosphate dehydrogenase, (ii) glucose phosphate isomerase, (iii) malate dehydrogenase, (iv) malic enzyme, and (v) phosphoglucomutase. As well, a fragment of the SSU-rDNA (292 bp) gene was amplified by PCR using the primers RH11 and RH4. The sequencing of the PCR products and phylogenetic tree were performed. The isoenzyme electrophoretic profiles divided fifteen G. duodenalis isolates into four zymodemes. G6PD, GPI, MDH, ME, and PGM enzyme systems showed 1, 2, 2, 3, and 3 enzyme pattern, respectively. G6PD isoenzyme pattern had the most homogeneity, while isoenzyme patterns of ME and PGM had the most heterogeneity in our study. Genotyping results indicated that the zymodemes 1–4 were categorized in assemblage A based on the SSU-rDNA gene. Phylogenetic analysis showed that all four zymodemes were distributed within the cluster of assemblage A. Our results indicated that both isoenzyme and DNA analyses were useful to characterize the isolates of Giardia and distinguishing various zymodemes and assemblages. It could be suggested that the genetic diversity among isoenzymes profiles of G. duodenalis may explain the variable clinical manifestations, pathogenicity, host response, drug susceptibility, and treatment efficacy of human giardiasis.