Several studies were carried out and drought coexistence technologies were developed to deal with the problem of drought in semiarid regions, such as the construction of underground dams, which became a tool for rural development, mainly for family agriculture. However, there are still scarce informations regarding technical studies on the water security level of underground dams, especially about trace metal contamination due to the use and agricultural occupation of the soils downstream of the dams. In this work, the level of contamination of trace metals in waters of underground dams, during two hydrological years, was evaluated around of the sub-basin of the Cobras river, in the Rio Grande do Norte state, Brazil. The analysis of the results indicated that the water samples stored in the Alexandre and Ginaldo underground dams are within the permitted drinking patterns and did not suffer, on the other hand, any alteration in their quality that requires treatment for human consumption, fitting into Class 1. Most of the samples from the waters of the Boa Vista and Ademar dams are above the maximum allowable value for iron (Fe), lead (Pb), chromium (Cr), and nickel (Ni), requiring a differentiated treatment for human consumption, and can be classified as Class 2. The probable contamination of the waters stored in the underground dams may be of geological origin, since the largest accumulation of trace metals occurred in the lower area of the river course greater drained area, leading to believe that the metals come from the rock weathering that make up the geological framework of the region.

In the present work, the interaction between temperature, relative humidity, wind speed, and wind direction was studied in the atmosphere of Patras port, and the following were found: The interaction between temperature and air particle concentration was synergistic in the absence of wind direction, this result being however false. The actual effect of temperature in the presence of wind direction was antagonistic in line with most of the authors of the international bibliography; i.e., increase of the temperature level resulted in a decrease of particle concentration per unit volume (cm³). On the other hand, increase of the relative humidity increased the particle concentration per cm³, while the interaction between temperature and relative humidity was also antagonistic; i.e., increase of temperature decreased accordingly the relative humidity, and vice versa. Similarly, the interaction between wind speed and relative humidity was also antagonistic and statistically significant. It is emphasized that the wind direction played an important role in determining the antagonistic or synergistic nature of the interactions between the meteorological factors, and especially, in controlling quantitatively the results (or outcomes), of the above interactions.

The impregnation process has successfully prepared a novel composite of iron oxide/carbon from black liquor (CA-BL/Fe) as an adsorbent for the removal of tripolyphosphate ions. Black liquor is a secondary product of the bioethanol pre-treatment process. X-ray diffraction results showed that the main iron oxide species present in the CA-BL/Fe was goethite (α-FeOOH). Interestingly, the specific surface area of CA-BL/Fe was 504 m²/g higher than that of commercial activated carbon of 356 m²/g. The adsorption performance showed that tripolyphosphate ion removal efficiency increased by increasing the adsorbent dosage, pH, and contact time. At the same time, it decreased with an increase in the initial concentration of tripolyphosphate. By controlling the environment pH value, the optimum removal efficiency of tripolyphosphate ions with CA-BL/Fe was 96.87%, with the adsorption capacity of 1.5922 mg/g for 1 h measurement. In this study, the dominant mechanisms of tripolyphosphate adsorption are electrostatic attraction and ion exchange. The result of this study is expected to be the basis for further promising adsorbent material for tripolyphosphate ion.

Many coastal communities rely on individual onsite wastewater treatment (i.e., septic) systems to treat and disperse wastewater. Proper wastewater treatment in these systems depends on sufficient volume of unsaturated soil below the drainfield’s infiltrative surface. This is governed by the vertical separation distance—the distance between the groundwater table and the drainfield infiltrative surface—which is specified in (regulatory jurisdictions’ onsite wastewater system) regulations. Groundwater tables along the southern New England coast are rising due to sea-level rise, as well as changes in precipitation and water use patterns, which may compromise the functioning of existing septic systems. We used long-term shallow groundwater monitoring wells and ground-penetrating radar surveys of 10 drainfields in the southern Rhode Island coastal zone to determine whether septic system drainfields have adequate separation distance from the water table. Our results indicate that only 20% of tested systems are not impaired by elevated groundwater tables, while 40% of systems experience compromised separation distance at least 50% of the time. Surprisingly, 30% of systems in this study do not meet separation distance requirements at any time of the year. Neither age of system nor a system’s geographical relationship to a tidal water body was correlated with compromised separation distance. The observed compromised separation distances may be a result of inaccurate methods, specified by the regulations, to determine the height of the seasonal high water table. Our preliminary results suggest that enacting changes in the regulatory permitting process for coastal zone systems may help protect coastal drinking and surface water resources.

This study examined behavioural intention to dispose of unused medicines using a comprehensive model integrating the theory of planned behaviour (TPB), with knowledge as a driver of personal norms; attitudes, personal norms, and perceived busyness as additional drivers of behavioural intention; and perceived convenience as a moderator. The model was tested with data collected from 204 respondents using the partial least squares technique. Knowledge about the proper disposal of unused medicines was recognized as a strong predictor of personal norms and attitudes towards proper disposal of waste medications. The results showed that attitudes, personal norms, perceived busyness, and perceived behavioural control have significant effects on intention to dispose of unused medicines. Furthermore, perceived convenience moderates the impacts of attitude, personal norms, and perceived behavioural control on intention to dispose of unused medicines. The extended TPB explained 55.7% of the variance of intention to dispose of unused medicines properly. Our results indicate the importance of integrating additional variables into the TPB to enhance its explanatory power in predicting behavioural intention. The results suggest to governments that in order to implement planned programs for proper collection and destruction of waste medication, a plan is needed to enhance public knowledge on the impacts of improper medication waste disposal on the environment, and also that collection points should become accessible for anyone.

Photocatalysis has emerged as a promising approach for treating environmental pollution. In this study, TiO₂/sponge composites with good photocatalytic activity in visible light were prepared via a simple and efficient low-temperature process and applied to the degradation of 2,4,6-trichlorophenol (2,4,6-TCP) present in papermaking wastewater. The process conditions for preparing TiO₂/sponge composites were optimized by varying the TiO₂ dosage, cellulose dosage, and surfactant concentration. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) results showed that TiO₂ successfully adhered to the sponge surface and that the composites achieved a good recycling effect. Degradation occurred under visible light, and a degradation rate of 81% for 2,4,6-TCP with initial concentration of 20 mg/L was achieved in 4 h. The fragments were analyzed using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS), which revealed the formation of 2-hydroxyvaleric acid (2-HVA) as a degradation product; a possible degradation mechanism is proposed to interpret these findings. Visible-light photocatalysis shows high potential for the rapid and environmentally friendly destruction of organic pollutants in papermaking wastewater.

The present study was designed to investigate the nephrotoxicity of silver nanoparticles (AgNPs; 80 mg/kg; > 100 nm) and to evaluate the protective effect exercised by Beta vulgaris (beetroot) juice (RBR; 200 mg/kg) on male rats’ kidney. Serum-specific parameters (urea, creatinine, electrolytes and histopathology of kidney tissue) were examined to assess the AgNPs nephrotoxicity effect. Moreover, this study analysed oxidative stress (lipid peroxidation, glutathione, superoxide dismutase and catalase) and anti-apoptotic markers (Bcl-2). AgNPs intoxication increased kidney function marker levels and lipid peroxidation and decreased the glutathione, superoxide dismutase and catalase activities in kidney tissue. Additionally, Bcl-2 expression was downregulated following AgNPs intoxication. Moreover, AgNPs induced a significant increase in renal DNA damage displayed as an elevation in tail length, tail DNA percentage and tail moment. Interestingly, RBR post-treatment restored the biochemical and histological alterations induced by AgNPs exposure, reflecting its nephroprotective effect. Collectively, the present data suggest that RBR could be used as a potential therapeutic intervention to prevent AgNPs-induced nephrotoxicity.

The possibility of superficial foot mycoses to spread through contaminated mosque carpets between worshipers imposes a great health burden and is never addressed in Riyadh, SA. We aimed to assess the prevalence of fungal infections, especially human dermatophytosis acquired from mosque carpets, in five different regions of Riyadh, Saudi Arabia and establish a means of contamination control. A cross-sectional study of 100 mosques in Riyadh, Saudi Arabia, was conducted, using a multistage random cluster sampling technique. The study included mosques that had an ablution area and regularly hosted five prayers a day. Sterile swabs were used for sampling, and the samples were transported to the laboratory for culture and analysis using a micro-scan system. A total of 199 (65%) samples contained several fungal species. Rhodotorula (74%), Cladosporium (47%), Bipolaris (46.6%), other yeasts (43.7%), Alternaria (40%), dematiaceous molds (34%), Curvularia (32.4%), and Candida (31%) were the most frequently isolated species. Species belonging to several other genera were also detected. This study revealed a relatively high prevalence of fungal organisms in mosque carpets in Riyadh, suggesting the need for implementing new strategies and laws to increase the level of hygiene awareness among worshipers and mosque caretakers to limit the spread of foot fungal infections.

The rapid and efficient determination of heavy metal content in food crops is essential for human health and environmental protection. The use of hyperspectral data has become a popular way to predict heavy metal content in plants; however, many challenges remain. One challenge is that lab conditions differ from actual agricultural production conditions. Another challenge is that spectral data characteristics are not universally applicable to all situations. Therefore, in this study, the field test method was adopted to conduct experiments during the full growth period of wheat, and the spectrum data of wheat canopy were processed by the first derivative method to screen-sensitive spectral bands as the basis for the prediction model of the copper content in wheat. The results showed that the copper content increased with an increase in the soil copper content, and there were dissimilar subtle differences in the spectral reflectance of wheat canopy under different stressed soil copper concentrations; sensitive spectral indices and wavelengths were screened based on good correlation with the copper content in the wheat canopy. Different optimal predicting models in different periods were built and verified. The established linear regression models, which were based on NDVI/SIPI and W728, were the most suitable predicting models during the tillering stage with R² = 0.669 and 0.818; Rg, W741, and multiple bands were the most suitable predicting models during the jointing stage with R² = 0.548, 0.830, and 0.868; the optimal model during the heading stage was based on W480 (R² = 0.625). This study demonstrated that the constructed models had good potential for estimating the copper content in wheat leaves during full growth periods, and this method had the potential to be applied to the actual agricultural production process.

The concern with the environment and the depletion of natural resources has aroused the interest for the rational use and recycling of water. Therefore, this study evaluated the capacity of the Trametes sp. M3 isolate in the bioremediation of Reactive Blue (RB) 268 dye and its potential for use as an adsorbent in the treatment of textile effluents. In a solid medium containing RB 268, the discoloration rate was 1.00 and the growth rate was 1.4 cm/day. When evaluated in the in vivo biodiscoloration process, 100% of the dye lost its color after 120 h. The oxidative enzyme laccase was found in cultures containing the dye with high activity, indicating that it underwent induction. The chromatogram after cultivation of the fungus showed that there was a change in the structure of RB 268. The mycelium of the culture with the dye was analyzed by FTIR, pointing to an adsorption of RB 268 or its metabolites despite the absence of the color. In the biosorption, the best results were obtained when the mycelium was treated with HCl. The toxicity of the medium decreased after the cultivation of the fungus allowing the survival of the microcrustaceans in the acute toxicity bioassay.