ABSTRACT Reusing textile wastewater represents a promising solution for meeting agricultural needs while preserving the environment amid increasing water scarcity. However, wastewater contains various pollutants and chemicals, thus effective treatment is needed to mitigate their impact on water quality and public health. In this study, we evaluated the effectiveness of combined biological treatment and hydrocyclone separation in improving textile effluent quality by analyzing their physicochemical properties and assessing the potential health risks using an in vivo food‐chain toxicological model. Corn irrigated with biologically treated wastewater (BTW) or with BTW subjected to hydrocyclone treatment (BTW+HT) was administered to Swiss mice for 30 days. Our findings revealed that BTW+HT resulted in significant reductions of 60% in color, 40% in total suspended solids, and 40% in chromium concentration. Moreover, mice fed corn irrigated with BTW+HT showed a significant reduction of approximately 39% in DNA damage, particularly in brain cells. Biochemical analysis revealed lower aspartate transaminase and alanine transaminase levels along with a restoration of superoxide dismutase activity, whereas malondialdehyde and NF‐κB levels revealed no significant changes. In addition, histological analysis showed no alterations in tissue structure. These findings demonstrate that the combination of hydrocyclone and biological treatment improves effluent physicochemical quality, with a concomitant reduction in the observed toxicological effects, supporting the potential of treated textile wastewater as an alternative resource able to tackle water shortage. Further studies are required to validate the long‐term safety and large‐scale applicability of this combined treatment strategy for agricultural reuse of textile wastewater.
ABSTRACT Excessive and long‐term fertilizer application degrades soil quality and negatively affects rice productivity. Integrated use of mineral fertilizer and biochar is an effective strategy to improve soil fertility and promote sustainable agricultural productivity. In the current research, the effect of different biochar doses in combination with reduced fertilizer dose was assessed on two rice varieties V1 (Super Basmati) and V2 and Al‐Khalid Basmati). During the planting phase, four different treatment combinations including BF1 (0 t ha −1 biochar + 149: 89: 62 kg ha −1; NPK) and 5 t ha −1 (biochar F2), 10 t ha −1 (biochar F3), and 15 t ha −1 (biochar F4) biochar doses with + 80% of recommended fertilizer (119: 71: 50 kg ha −1 ; NPK) were added in the soil before conducting ongoing experiment. Plant height (cm), the number of tillers (m −2 ), panicle length (cm), harvest index (%), number of spikelets per panicle, grain yield (tons ha −1 ), biological yield (tons ha −1 ), and 1000‐grain weight (g) were increased with the application of biochar. In conclusion, the performance of BF2 followed by BF3, FB4, and BF1 improved yield irrespective of varietal differences. In addition, higher rice productivity was affirmed by V2 variety as compared with V1. Biochar coupling with fertilizer in reduced combinations increased the organic matter, and nutrient dynamics that ensured promoted growth and yield attributes of rice by minimizing fertilizer demands. Therefore, an integrated dose of 5 t ha − 1 combined with reduced fertilizer application is recommended to enhance the yield potential of rice while maintaining agroecosystem sustainability and ecological balance.
ABSTRACT Air pollution is a major threat to human health. The restriction policies adopted in response to the spread of COVID‐19 had a significant effect on air pollution. In this paper, we studied the changes in air pollution in Beijing from 2019 to 2023 and the associated impact on premature mortality. PM 2.5 , NO 2 , SO 2 , and CO concentrations have continued to decrease since the COVID‐19 outbreak. Notably, the decrease in “Traffic” stations in 2020 exceeded that of “Urban” and “Rural” stations. This reflects the significant suppression of anthropogenic emissions, especially traffic emissions, in Beijing during the COVID‐19 lockdown period. When the lockdown was eased in 2023, the concentrations of PM 2.5 , PM 10 , and NO 2 increased to varying degrees (approximately 10%–40%). The AQI reflects the same characteristics, with continuous improvement from 2019 to 2022 and deterioration in 2023. In summer, the AQI was affected mainly by the lockdown policy, whereas in winter, the effects of the policy were superimposed by atmospheric conditions. The AirQ+ results show that the COVID‐19 restrictions significantly reduced the attributable fraction of deaths due to air pollution. However, PM 10 , NO 2 , and O 3 still pose considerable threats to the respiratory and circulatory systems of Beijing residents. Even if the concentration of pollutants decreases, the estimated number of deaths may still increase in the context of the continued increase in the population at risk; thus, it is necessary for local authorities to focus on controlling air pollution.
ABSTRACT This study evaluated peanut shell‐derived biochars prepared via oxygen‐limited pyrolysis (PSA, 300°C–600°C) and nitrogen‐pyrolysis (PSN, 300°C–700°C) as adsorbents for SO 2 and toluene removal from dry flue gas. Increasing pyrolysis temperature enhanced textural properties, with surface areas reaching 281.6 m 2 ·g −1 (PSA600) and 222.73 m 2 ·g −1 (PSN700), while oxygen‐containing groups decreased and aromatic carbon and crystalline minerals (SiO 2 , CaCO 3 ) increased. XPS confirmed stabilized active sites (pyridinic N, C–O/C–N) at higher temperatures, facilitating pollutant capture. Adsorption performance improved with temperature: PSA600 achieved a toluene adsorption capacity of 50.6 mg·g −1 (2.37× PSA300), and PSN700 achieved an SO 2 adsorption capacity of 24.8 mg·g −1 (11.26 × PSN300). Kinetic modeling showed temperature‐dependent rate‐limiting steps, but high R 2 values for both pseudo‐first‐order and pseudo‐second‐order models indicated that kinetics alone cannot unambiguously reveal the mechanism, requiring complementary characterization. Overall, pyrolysis temperature and atmosphere jointly govern the trade‐off between pore development and surface chemistry, providing a basis for the rational design of low‐cost biochars for multi‐pollutant control and agricultural waste valorization.
ABSTRACT Phosphorus (P) loss to aquatic systems poses a dual challenge of eutrophication and depletion of finite phosphate‐rock resources. This study developed chitosan (CS) hydrogel beads containing CaFe layered double hydroxide (LDH) for phosphate removal and potential nutrient reuse. Incorporation of CaFe‐LDH increased the BET specific surface area from 6 to 28 m 2 g − 1 and enhanced phosphate adsorption. Among six formulations, CS/CaFe4 exhibited the highest phosphate adsorption capacity and was selected for further evaluation. Phosphate adsorption approached equilibrium within approximately 8 h. The maximum experimental adsorption capacity was approximately 42 mg P g − 1 , and the Langmuir‐estimated maximum capacity was 41.8 mg P g − 1 , although the Freundlich model provided a slightly better fit than the Langmuir model. Phosphate adsorption remained relatively stable from pH 4 to 11 but declined sharply at pH 3. Cl − , NO 3 − , and SO 4 2 − had limited effects, whereas HCO 3 − reduced adsorption and Ca 2 + and NH 4 + enhanced phosphate adsorption. Phosphate‐loaded hydrogel released 0.10–0.14 mg P L − 1 in each of five sequential 24‐h water‐extraction cycles. In a 14‐day wheat ( Triticum aestivum ) bioassay, observed seed germination was higher with phosphate‐loaded hydrogel than in unamended soil; however, fresh hydrogel produced a similar response, whereas superphosphate produced the highest germination. Seedling length was similar among treatments. Collectively, these results identify CS/CaFe4 as a promising material for P capture and demonstrate that a measurable fraction of adsorbed P can be released from the phosphate‐loaded hydrogel. Longer‐term soil and plant studies are needed to determine P bioavailability, fertilizer value, and the feasibility of agricultural reuse.
