In this study, mature seeds of Zea mays (Malka 16) were irrigated with untreated and UASB-treated wastewater with combination of 50% textile and 50% sewage at hydraulic retention times (HRTs) of 0, 5, 10, and 15 h. Four other treatments diluted with distilled water (DW) were also evaluated. Eight-week analysis of irrigation revealed very small differences in the results of plant biomass and growth parameters of control and those irrigated with 15 h (HRT) treatments. The values of both types of water were observed as chlorophyll a and b contents, 5.9, 3.4, vs 5.5, 3.1 mg g⁻¹, total chlorophyll 9.4 vs 8.8 mg g⁻¹, carotenoids 9.5 vs 8.7 mg g⁻¹, spad values 61.4 vs 56.3, net photosynthetic rate (A) 15.6 vs 14.5 μmol m⁻² S⁻¹, transpiration rate (E) 3.98 vs 3.8 μmol m⁻² S⁻¹, stomatal conductance 5.9 vs 5.8 μmol m⁻² S⁻¹, water use efficiency 10.3 vs 9.7 mmol Cmm⁻¹ H₂O, electrolyte leakage 115 vs 98% and total soluble proteins 385 vs 354 in leaves and 260 vs 231 g⁻¹ FW in roots. While this stress enhanced H₂O₂ 92 vs 115 and 195 vs 224 Units g⁻¹, MDA 6.8 vs 9.1 and 5.9 vs 8.3 Units g⁻¹, activities of enzymatic antioxidants SOD 25 vs 63 and 54 vs 63 Units g⁻¹, POD 1170 vs 1310 and 570 vs 650 Units g⁻¹, CAT 570 vs 820 and 880 vs 1040 Units g⁻¹, and APX 235 vs 278 and 134 vs 187 Units g⁻¹ in leaves and roots, respectively. Heavy metals (Cd, Cr, Cu, and Zn) in such plants were mostly within or about permissible limits of NEQS. The results obtained were more close to that of control. This practice may lead to clean environment and its reuse shall also reduce the stress on fresh water. Early researches transpire a little work done on the reuse of UASB-treated textile wastewater with co substrate, for irrigation purpose.

This study investigates the relationship between climate change, the area under cultivation, fertilizer consumption, and cotton production in Pakistan from 1980 to 2018. The existence and nature of the short-term and long-term relationships are explored by using an autoregressive distributed lag (ARDL) model bounds testing approach. The estimated result of the ARDL bounds testing approach has shown the presence of cointegration between dependent and explanatory variables. The long-term estimates have revealed that the increasing average temperature has a positive insignificant effect, which implies that rising temperature is not increasing cotton yield in Pakistan. The findings of the area under cultivation and fertilizer consumption have revealed significant positive effects in both the long run and short run. This study urges Pakistan to reduce the pace of climate changes and increase water conservation by planting forests and constructing dams across major rivers along with the adoption of environmentally friendly production techniques and inputs.

The aim of the present study was to investigate changes in the locomotor activity of rainbow trout (Oncorhynchus mykiss) juveniles under the impact (2 h) of landfill leachate (as a multicomponent mixture) based on different endpoints such as average, maximum and angular velocities, movement duration, body mobility, and blood glucose level. Fish were exposed to five different sublethal leachate concentrations (0, 0.0625, 0.125, 0.25, and 0.5%). The locomotor activity of the leachate-exposed fish significantly decreased at 0.25 and 0.5% concentrations. Significant changes in fish behavior in response to sublethal leachate concentrations were determined during the first minutes of exposure. Angular velocity proved to be the most sensitive of all the endpoints tested. A positive correlation was observed among behavioral responses, but no correlation was established between the blood glucose level and behavioral endpoints. The blood glucose endpoint was found to be insensitive, and we suggest that it should be used only in combination with other endpoints to complement toxicity data. To enhance the understanding of rainbow trout behavioral characteristics in relation to time, and relations among behavioral endpoints of the fish under short-term exposure to a multicomponent mixture, in the current study, we investigated dynamics of the selected behavioral endpoints over time, relations among these endpoints and compared behavioral response rapidness and efficacy.

Water pollution by heavy metals has many human origins, such as the burning of fossil fuels, exhaust gases of vehicles, mining, agriculture, and incineration of solid and liquid wastes. Heavy metals also occur naturally, due to volcanoes, thermal springs activity, erosion, infiltration, etc. This water contamination is a threat for living beings because most heavy metals are toxic to humans and to aquatic life. Hence, it is important to find effective techniques for removing these contaminants in order to reduce the level of pollution of the natural waters. In this work, we have reviewed the toxicity of several heavy metals (mercury, lead, cadmium, chromium, nickel), their impact on the environment and human health, and the synthesis and characterization methods of conducting organic polymers (COPs) utilized for the removal of heavy metals from the environment. Therefore, this review was essentially aimed to present recent works and methods (2000–2020) on the environmental impact and toxicity of heavy metals and on the removal of toxic heavy metals, using chemically and/or electrochemically synthesized COPs. We have also stressed the great interest of COPs for the removal of toxic heavy metals from waters.

This manuscript communicates the use of cement-coated red bricks for augmenting the production of distilled water using a traditional single slope solar still by low cost energy storage. The exposure area of water is increased in modified solar still (MSS) by keeping the cement-coated red bricks in the absorber. Using the energy storage material in the absorber, the water temperature was higher in the case of MSS at 20 kg water mass which was the minimum mass used during the experiment in the basin. From the results, it was also found that there is an improvement of about 34% in the temperature of water which acts as the driving force for evaporation of water inside the closed chamber. Furthermore, with increase in water temperature the productivity was enhanced by 45% as compared to the CSS. Comparison of different solar still on productivity was also analysed, and it is seen that the yield is higher in the present study by 38.8% than double slope-double basin solar still with different energy storage. The daily yield from CSS for water depth of 20, 30, 40 and 50 was found as 3.2, 2.8, 2.7 and 2.6 kg, whereas the modified solar still produced 6.3, 6, 5. 8 and 5.6 kg, respectively. Due to the reduced daily yield at higher water masses, the cost per litre of water produced from both conventional and modified solar still is higher.

The original publication of this paper contains a mistake.

Agrochemicals are one the most significant sources of environmental pollution. Cytotoxicity and genotoxicity are the serious side effects of fungicide. In the current study, I have evaluated acute cytotoxicity and genotoxicity of triphenyltin (TPT) on human hepatic carcinoma (HepG2) cells and the ameliorating effect of ascorbic acid for 24 h. In this experiment, I have exposed HepG2 cells to ascorbic acids (50, 100, and 200 μM) simultaneously and 24 h prior triphenyltin (TPT, 400 ng/ml) exposure for 24 h to determine the protective effect of ascorbic acid by using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and NRU (neutral red uptake) assays. Oxidative stress, such as intracellular reactive oxygen species and glutathione levels, was measured in HepG2 cells. The intracellular reactive oxygen species was evaluated using fluorescent probe DCFDA (6-carboxy-2′,7′ dichloro-dihydrofluorescein diacetate). Apoptosis and genotoxicity effects of TPT in HepG2 cells were determined using flow cytometry and comet assay. The result of these experiments showed that the TPT compound (400 ng/ml) induced cytotoxicity, oxidative stress and apoptosis, and DNA damage in HepG2 cells.Ascorbic acid reduced cytotoxicity, oxidative stress, apoptosis, and genotoxicity induced by TPT. Thus, ascorbic acid is a potent antioxidant, and it showed a significant protective effect against toxicity induced by TPT in HepG2 cells.

Sludge pyrolysis is a complex process including complicated reaction chemistry, phase transition, and transportation phenomena. To better evaluate the use of syngas, the monitoring and prediction of a higher heating value (HHV) is necessary. This study developed an artificial neural network (ANN) model to predict the HHV of syngas, with the process variables (i.e., sludge type, catalyst type, catalyst amount, pyrolysis temperature, and moisture content) as the inputs. In the first step, through optimizing various sets of parameters, a three-layer network including 8 input neurons, 15 hidden neurons, and 1 output neuron was established. Then, in the second step, an ANN model has been successfully used to predict the HHV of syngas, with a fitting correlation coefficient of 0.97 and a root mean square error (MSE) value of 14.62. The relative influence of input variables showed that the pyrolysis temperature and moisture content were the determining factors that affected the HHV of syngas. The results of optimization experiments showed that when temperature was 895 °C and the moisture content was 45.63 wt%, the highest HHV can be obtained as 438.22 kcal/m³-N. Moreover, the ANN model showed a higher prediction accuracy than other models like multiple linear regression and principal component regression. The model developed in this work may be used to predict the HHV of syngas using conventional operational parameters measured from in situ experiments, thus further providing predictive information for the use of syngas as energy and fuel.

Pharmaceuticals are detected at trace levels in water. Their adverse effects on human health and aquatic ecosystems required novel pharmaceutical remediation methods for treating wastewater effluents. Layer double hydroxide (LDH) is abundantly available by simple preparation methods and with low costs. The extensive use of antibiotics nowadays leads to increasing the appearance of antibiotic resistance between bacteria and decreasing the effectiveness of antibiotics. In this work, the removal of one of these antibiotics named “oxytetracycline hydrochloride (OTC)” by Zn/Fe LDH was investigated. The Zn/Fe LDH before and after adsorption was characterized by X-ray diffraction, FT-IR analysis, zeta potential, particle size, BET surface area, HRTEM, FESEM, and XPS. The effects of different factors on the OTC adsorption performance were investigated. The removal percentage of OTC was 77.23% by Zn/Fe LDH. The isothermal and kinetic study of OTC adsorption was carried out at pH 6 at 25 °C using different models. The adsorption mechanism was investigated by Monte Carlo and molecular dynamic simulations.