Recent studies have shown that exposure to hydrothermal emissions has a negative impact on the respiratory system. Still, volcanogenic air pollution studies are still outnumbered when compared to anthropogenic studies which can result in an unknown risk to the human populations living near volcanically active areas. This study was carried out in São Miguel Island, with noneruptive volcanically active environments, such as the Furnas volcano caldera. Its noneruptive volcanism presents itself as hydrothermal emissions, mainly by the release of nearly 1000 T d⁻¹ of CO₂ along with H₂S, and the radioactive gas radon; metals [e.g., mercury (Hg), cadmium (Cd), copper (Cu), and zinc (Zn)] and particulate matter are also released in a daily basis. We test the hypothesis whether chronic exposure to hydrothermal emissions causes pulmonary oxidative stress, using Mus musculus as a surrogate species. Mus musculus was live-captured in two villages with hydrothermal emissions and one village without any type of volcanic activity. The level of pulmonary oxidative stress was immunohistochemically assessed by using an OxyIHCᵀᴹ Oxidative stress detection kit, and the detection of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) was used to evaluate apoptosis in lung tissues. Mice chronically exposed to hydrothermal emissions presented increased levels of oxidative stress and amount of apoptotic cells. We demonstrate, for the first time, the high oxidative stress potential in the lungs of mice chronically exposed to hydrothermal emissions. This study highlights the usefulness of M. musculus as a bioindicator species and enforces the necessity of regularly biomonitor the inhabitants of hydrothermal areas to prevent respiratory pathologies.

Global warming is one of the most serious environmental problems that the world faces today. Millions of human lives are at risk, hence the subject has gained enormous attention within academia and the research arena. Literature shows that the primary cause of global climate change or global warming is carbon (CO₂) emissions. In the literature, a number of studies have investigated the factors affecting the overall level of carbon emission. However, in recent years, consumption-based carbon emissions have occupied the center stage in research related to international trade and environmental concerns. The recently emerged idea of carbon emissions based on consumption differs from conventional accounting (i.e., carbon emissions based on production) in that it highlights the importance of international trade in national carbon emissions. Unlike the previous studies that examined the symmetric effect of international trade on consumption-based carbon emission, the present study examines the asymmetric effect of international trade on consumption-based carbon emissions of emerging economies. To get empirical estimates, the study applies a Nonlinear Panel Autoregressive Distributive Lag (NPARDL) approach. The estimates show that both in the short and long run, a positive shock in exports significantly reduces consumption-based carbon emissions in developing economies. Whereas, a negative shock in exports has an insignificant impact on carbon emissions. For imports, the results show that, over time, positive shocks in imports significantly increase consumption-based carbon emissions, while the impact of negative shocks is insignificant. Finally, it is recommended for the policymakers to target the export industries for relevant policy interventions, which are less polluting but crucial for economic growth.

The nanometer effect in the process of arsenic ions removal on α-MnO₂ nano-surface is studied by the first-principle method through microfacet models. Several parameters, such as adhesion energy, electrostatic potential, and Mulliken population were calculated to illuminate the internal mechanism. The results show that the adsorption energies of As(OH)₃ molecules on MnO₂[(100×110)] nanostructure are smaller than that on the bulk surface with the same concentration, which means the nanometer effect is beneficial to enhance the adsorption ability of MnO₂ nano-surface. In an aqueous solution, there exist two possible removal ways of As ions. One is the direct reaction of As(OH)₃→As(OH)₆⁻, which occurs both in bulk surface and nano-surface. However, to nanomaterials, there exists another removal way of As(OH)₃→As(OH)₄→As(OH)₆⁻ through an intermediate As(OH)₄ molecule produced by nanometer effect. Furthermore the smaller electrostatic potential of As ions on [(100×110)] nano-surface is beneficial to enhance the removal capability of As ions. Then the reason why MnO₂ nanomaterials have better catalytic activity than the bulk materials is originated from its much less adhesion energy, much more removal ways, and much smaller electrostatic potential. So this research provides a detailed understanding of the removal capability of toxic ions influenced by a nanometer effect.

We investigated the accumulation of Zn, Cu, Pb, and Cd in the soil and the leaves and bark of five common tree species (Eucalyptus occidentalis Endl., Acacia salicina Lindl., Cupressus sempervirens L., Casuarina equisetifolia L., and Tamarix aphylla (L.) Karst.) in the city of Gabès Tunisia to elucidate their bioaccumulation potential and determine their usefulness as biomonitors of metallic pollution in arid urban areas. Our results indicated that the bark had higher mean concentrations of Pb and Cd than leaves. In contrast, the leaves had higher mean concentrations of Zn and Cu than bark. No hyperaccumulation was detected for any of the analyzed metals in any of the studied species. E. occidentalis and T. aphylla had the highest mean concentrations of the investigated metals in leaves and bark. Based on the calculated metal accumulation index (MAI) values, these two species accumulated more metals than other studied tree species. Likewise, the concentrations of Zn, Cu, Pb, and Cd in soil had significant positive correlations with that in leaves and bark. Accordingly, E. occidentalis could be used for biomonitoring in arid areas subjected to industrial and traffic pollution. T. aphylla would be a good alternative when native species are a priority.

Chlorpyrifos (CPF) is an extensive environmental contaminant and disrupts the physiological status of living organisms. CPF is found to hinder the health of aquatic organisms and ecological function in aquatic systems. The current study aimed at evaluating the protective effects of vitamin C (VC) on the immune response, hematological parameters, and histopathological alterations in Nile tilapia exposed to CPF. Nile tilapia were exposed to waterborne CPF (15 μg/L) for 30 days. Fish were divided into control group: received basal diet; CPF group: received basal diet and exposed to waterborne CPF; VC group: received basal diet plus 0.8 mg VC/kg; and CPF/VC group: received basal diet plus 0.8 mg VC/kg and exposed to waterborne CPF. Blood samples were taken after 15 days and 30 days of the treatment. Liver, gills, and intestine tissues were collected on the 30th day of treatment. CPF showed a deleterious effect on fish’s growth performance; it decreased the weight gain by 6%, while VC increased it by 17–23% compared to the control group. CPF group recorded the lowest survival rate (83%), while VC achieved survivability of 96.7% and 93.3% in VC and CPF/VC groups, respectively. The blood picture revealed moderate changes in the CPF group, where the marked alteration was in the hemoglobin concentration and white blood cells. CPF disrupted the hepatic and renal function. Serum lysozyme activity, phagocytic activity, and phagocytic index displayed a dramatic decline in the CPF group but enhanced in VC and CPF/VC groups. An upregulation was observed in antioxidant genes (catalase and glutathione peroxidase), heat shock protein 70, caspase-3, and the cytokines interleukin 1β, interleukin 8, and interferon-gamma in the CPF group. Simultaneously, moderate or normal levels were shown in the VC and CPF/VC groups. CPF altered the histoarchitecture of gills, intestine, and hepatopancreas with apparent degenerative changes possibly resulted from the oxidative stress. At the same time, VC retained the normal structure of the studied tissues. This study raises concerns about the safety of CPF and its impact on the aquatic environment. VC has a high potential to restore the normal physiology of fish exposed to CPF.

Agroecological productivity of the Arganeraie Biosphere Reserve of Morocco is limited by the wide spread and dynamics of plant parasitic nematodes (PPN). Ecological studies of nematode communities are required to develop effective biological management of these bioagressors as conventional control methods of PPN are inadequate and have persistent harmful effects. Fifty-nine organic vegetable soils in Souss-Massa were nematologically sampled, and assessment of taxonomic proliferation was made in relation to host species, geographical origin, and climatic and microclimatic factors. Twenty-four nematode genera were identified as obligate and facultative plant feeders. Taxonomic diversity increased from Chtouka to Taroudant and Tiznit provinces. Soil texture, organic matter, pH, nitrogen, zinc, magnesium, copper, altitude, and humidity and temperature were seen to effect driving roles in the abundance, distribution, and community structures of nematodes. The most prevalent taxa posing a high risk to organic agriculture of Souss Massa were needle nematodes (Longidorus spp.) and root-knot nematodes (Meloidogyne spp.). Edaphic and climatic variables effected nematode populations greatly. A combination of biological treatments and appropriate agroecological practices restricting important economic PPN growth and enhancing soil quality are required to achieve sustainable management in the area.

Fe-bearing salt and minerals are common reagents used in activating peroxymonosulfate (PMS) for Fenton-like oxidation in wastewater treatment. Fe-bearing reagents are used in mass production, which generate abundant Fe-bearing waste sludge in the absence of a reductant for Fe³⁺/Fe²⁺ cycling. Herein, a novel Fe/S-bearing mineral, erdite, was synthesized with a one-step hydrothermal route. The material exerted an Fe/S synergetic effect for p-nitrophenol degradation upon PMS activation and showed a one-dimensional structure similar to that of (FeS₂)ₙⁿ⁻. It contained short rods with diameters of 100 nm and lengths ranging from 200 to 400 nm. It grew radically to 0.8–2 μm in length upon the addition of MnO₂. Ps-0.5, prepared by adding MnO₂ in an Mn/Fe molar ratio of 0.5, showed optimal efficiency in removing approximately 99.4% of p-nitrophenol upon PMS activation. Only 3.3% of p-nitrophenol was removed without MnO₂. The efficiency of p-nitrophenol removal through Ps-0.5 activation was higher than that through FeSO₄, nanoscale zero-valent iron (nZVI), CuFeS₂, and MnSO₄ activation. The formed erdite rods were spontaneously hydrolyzed to Fe/S-bearing flocs, in which an electron was used by structural S to reduce Fe³⁺ to Fe²⁺ upon PMS activation. The reduction resulted in a high p-nitrophenol removal rate. This study provided new insight into the development of an effective PMS activator in wastewater treatment.

Accumulation of heavy metals in the coastal ecosystem has become a prodigious problem in any developing countries like Bangladesh. The impact of human activities on some physicochemical parameters and heavy metals was studied in surface water of the Bengal coast, Bangladesh. For ease of description, the fourteen study stations were categorized into four regions of the coastal sites of Bangladesh to determine physicochemical parameters and nine heavy metals like chromium (Cr), nickel (Ni), copper (Cu), arsenic (As), cadmium (Cd), lead (Pb), iron (Fe), manganese (Mn), and zinc (Zn) in water samples. The mean concentrations for water physico-chemistry are temperature (27.7±1.2 °C), pH (7.4±0.27), electrical conductivity (EC) (41.8±6.6 mS/cm), dissolved oxygen (DO) (6.7±0.69 mg/L), turbidity (58.5±12.0 NTU), fluoride (1.4±1.2 mg/L), chloride (126±66.3 mg/L), sulfate (120±90.5 mg/L), nitrate (4.7±2.5 mg/L), and phosphate (4.7±2.5 mg/L). While the mean concentrations of Cr, Ni, Cu, As, Cd, Pb, Fe, Mn, and Zn were 150±58.3, 40.2±10.1, 186±114, 77.3±31.3, 32.7±20.7, 66.7±32.5, 871±268, 178±41.4, and 222±100 μg/L, respectively. As a whole, average concentration of studied metals in surface water followed the decreasing order of Fe > Zn > Cu > Mn > Cr > Pb > As > Ni > Cd. Heavy metals in water samples were much higher than the water quality guidelines for freshwater quality criteria for protection of aquatic life and drinking, indicated that the water of the study areas may create health hazard. The outcomes of the contamination factor (CF), pollution load index (PLI), Nemerow’s pollution index (NPI), degree of contamination (Cd), and modified degree of contamination (mCd) varied spatially and most of the water samples were moderately to heavily polluted.

Nowadays, the soil arsenic pollution is considered as a serious environmental issue, and the high toxicity of arsenic can seriously affect the quality and safety of agricultural products and human health. Biochar, as a solidifying/passivating agent, has been widely used in the treatment of soil heavy metal pollution. Pine biochar (BC) was used as a carrier in this study, and biochar-loaded nano-zirconia (N-ZrO₂-BC) was synthesized to investigate its adsorption and fixation characteristics on As (V) in soil and water. The adsorption experiment showed that the second-order kinetic equation had a good fitting effect on the adsorption curve of As (V) on the N-ZrO₂-BC surface, which indicated that chemical adsorption was the main factor controlling the reaction rate. FTIR and SEM results showed that ion exchange and surface complexation were the main mechanisms of As (V) adsorption by N-ZrO₂-BC. Soil culture experiments showed that the stabilization efficiency of arsenic in soil with 2% N-ZrO₂-BC reached 99.30% after 60 days, and the extractable arsenic content was reduced to 3.07 μg·L⁻¹, which reached the quality standard of class III groundwater (<0.01 mg·L⁻¹, GB/T 14848-2017). Comparing with the control, the content of acid extractable arsenic in soil decreased by 90.57%, and the residual arsenic increased by 51.46%, indicating that the addition of N-ZrO₂-BC could effectively promote the transformation of active arsenic to stable arsenic in soil.

This study presents an analytical strategy named silica nanoparticles (Si-NP) based pipette tip solid phase extraction (PT-SPE) method for the trace level determination of cadmium in mineral water samples. Slotted quartz tube flame atomic absorption spectrophotometry (SQT-FAAS) was used to determine the cadmium analyte. Si-NPs synthesized from rice husk were used to preconcentrate/extract the cadmium ions. Adsorbent properties of Si-NPs were examined by SEM analysis and the size of nanoparticles was found in nanoscale. The extraction/preconcentration and phase separation steps are carried out simultaneously which greatly reduces the extraction time by eliminating the need for centrifugation step before phase separation. The effect of all experimental parameters on the efficiency of the developed method was examined and optimized utilizing univariate optimization strategy. The linear calibration graph of the developed method showed a good linearity between 0.60 and 20 µg/L and the limit of detection was calculated as 0.16 µg/L. The presented method showed an approximately 194-fold enhancement in detection power compared to traditional FAAS. The developed method’s applicability to real samples was validated through spiking experiments in mineral water samples using the matrix matching strategy. The percent recoveries calculated were ranged between 92 and 98% with RSD values lower than 10%, confirming the applicability of the developed method for the precise determination of cadmium in mineral water samples. The developed method offers a simple and rapid extraction/preconcentration of the target analyte from the aqueous sample solution.