The factors limiting micropollutant biodegradation in the environment and how to stimulate this process have often been investigated. However, little information is available on the capacity of microbial communities to retain micropollutant biodegradation capacity in the absence of micropollutants or to reactivate micropollutant biodegradation in systems with fluctuating micropollutant concentrations. This study investigated how a period of 2 months without the addition of micropollutants and other organic carbon affected micropollutant biodegradation by a micropollutant-degrading microbial community. Stimulation of micropollutant biodegradation was performed by adding different types of dissolved organic carbon (DOC)—extracted from natural sources and acetate—increasing 10 × the micropollutant concentration, and inoculating with activated sludge. The results show that the capacity to biodegrade 3 micropollutants was permanently lost. However, the biodegradation activity of 2,4-D, antipyrine, chloridazon, and its metabolites restarted when these micropollutants were re-added to the community. Threshold concentrations similar to those obtained before the period of no substrate addition were achieved, but biodegradation rates were lower for some compounds. Through the addition of high acetate concentrations (108 mg-C/L), gabapentin biodegradation activity was regained, but 2,4-D biodegradation capacity was lost. An increase of bentazon concentration from 50 to 500 µg/L was necessary for biodegradation to be reactivated. These results provide initial insights into the longevity of micropollutant biodegradation capacity in the absence of the substance and strategies for reactivating micropollutant biodegrading communities. Graphical abstract: (Figure presented.)

Water plays a crucial role in the environment and in the process of liquefaction, which can occur during moderate to major earthquakes and cause significant structural damage. Liquefaction is defined as the transformation of granular material from a solid state to a liquid state, a process driven by increased pore water pressure and reduced effective stress within the soil. When an earthquake strikes, the shaking causes the pore water pressure between the sand grains to rise, which in turn reduces the contact forces between the grains. As a result, the sand loses its effective shear strength and starts to behave more like a fluid, leading to instability and potential collapse of structures built on such ground. Liquefaction can occur in moderate to major earthquakes, resulting in severe damage to structures. The transformation of granular material from a solid state to a liquid state due to increased pore pressure and reduced effective stress is defined as liquefaction. When this happens, the sand grains lose their effective shear strength and will behave more like a fluid. This phenomenon of dissolution of soil damages trees’ stability and disturbs the formation of the earth’s surface. Liquefaction resistance of soil depends on the initial state of soil to the state corresponding to failure. The liquefaction resistance can be evaluated based on tests on laboratory and in situ tests. For this research, liquefaction resistance using in-field tests based on SPT N values is attempted. Cyclic resistance ratio (CRR) is found based on the corrected N value. About 16 bore logs have been selected for the factor of safety calculation. The factor of safety for soil was arrived at by taking into account of corresponding corrected SPT N values. The liquefaction hazard map is prepared for the moment magnitude of 7.5-7.6 M w. It is also found that the areas close to water bodies and streams have the factor of safety less than unity. The bore log of locations having a factor of safety less than one indicates that up to a depth of about 6 m, very loose silty sand with clay and sand is present, which are defined as medium to fine sand having low field N values.

This study was performed to determine the effect of synthesized iron oxide nanoparticles on the consortium of isolated bacterial strains from the crude oil-contaminated site. The iron oxide nanoparticle (FeNPs) was synthesized by chemical co-precipitation method and confirmed with its characterization results such as UV-spectroscopy, X-ray Diffraction (XRD), High-Resolution Scanning Electron Microscopy (HR-SEM), Zeta potential and Particle Size Analyser studies. The isolates were cultured in LBBH (Luria-Bertani and Bushnell Haas) medium containing crude oil as a carbon source with incubation for 7 days. This study was performed using FeNPs with four different concentrations (10, 50, 100 and 150mg) incorporated with the isolated microbes clubbed as a consortium. The rate of biodegradation was investigated by gas chromatography-mass spectrometry (GC-MS) analysis. By comparing the control sample (crude oil) there was a better degradation in FeNPs added bacterial culture than consortium degradation. The obtained results conclude that studying different concentrations of FeNPs with the consortium of isolated microbes showed degradation differences, whereas 150mg concentration has a better degradation effect compared to other variations. It should be carried out to avoid agglomeration of nanoparticles by improving their biocompatibility and quality to influence the biodegradation of crude oil.

This study investigates the relationship between green marketing practices and the sustainability performance of manufacturing firms in emerging markets. A self-administered questionnaire was used to collect data from 270 respondents, and the analysis was conducted using Smart PLS-SEM (version 4). The results demonstrate a significant positive relationship between green internal marketing and the overall sustainability performance of the firms. Specifically, green marketing communication was found to positively influence both environmental and social performance, although it did not have a significant effect on financial performance. Likewise, the adoption of green products substantially improved environmental performance but did not significantly impact financial or social performance. Additionally, the study supports a positive association between green strategy implementation and sustainability performance. These findings underscore the critical role of integrating green marketing practices into sustainability initiatives. The research provides valuable insights for managers and policymakers, emphasizing the need for a holistic approach to green marketing to enhance environmental and social outcomes, even if financial benefits are not immediately apparent. This study contributes to the growing body of knowledge on sustainable business practices and offers practical implications for achieving long-term sustainability in manufacturing firms.

Mycoremediation is classified as an inexpensive, environmentally friendly, and effective technique to reduce wastewater. Leiotrametes menziesii BRB 73 was one of the White Rot Fungi (WRF) that has the potential to degrade dyes. Suitable environmental conditions can optimize dye decolorization results. This study aims to investigate optimal environmental conditions such as time incubation, concentration of dyes, pH, CuSO4, and glucose concentration against decolorization of a mixture of direct dyes and enzyme activity (laccase and MnP). The mixture of commercial direct dyes used contains direct turquoise (DT), direct orange (DO), and direct yellow (DY) dyes. Decolorization was measured using a spectrophotometer at 400-700 nm. Laccase and MnP assay using ABTS and 2.6 DMP as substrate, respectively. The highest decolorization by Leiotrametes menziesii BRB 73 was produced at 54.3% at 96 hours and increased to 67% at a dye concentration of 500 mg.L-1. Meanwhile, the highest laccase and MnP activities were 215 U.L-1 and 39 U.L-1, respectively. pH range was quite wide, ranging from pH 5.5-9, supported by stable MnP activity from pH 3-7. CuSO4 inducers were not required for the decolorization of these dyes. Decolorization was optimal at the addition of 1% glucose, while enzyme activities were 0.5% glucose. Decolorization of dyes by Leiotrametes menziesii BRB 73 was indicated through degradation pathways involving laccase and MnP enzymes. This isolate has a high tolerance to dye concentrations, a wide pH range, and low carbon requirements. Thus, it was recommended as a mycoremediation agent.

Improper disposal of landfill leachate, a highly polluted wastewater, can harm living beings and the ecosystem. Of all the treatment technologies available, electrochemical techniques have the most advantages in terms of ease of use, affordability, and the ability to degrade various contaminants found in landfill leachate effectively. Though there are a sufficient number of research articles regarding the electrochemical treatment of leachate, it has many research gaps, such as a study on the mechanism of radicle generation, pollutant degradation, study on different electrodes with various pollutants concentrations, application of green catalysts, byproduct formation assessment, energy recovery, etc. This review article explores the applications of electrooxidation techniques for the treatment of landfill leachate. Key aspects discussed include the (i) fundamental concepts in electrochemical treatment and its mechanism, (ii) factors affecting the electrochemical treatment efficiency, (iii) the applicability of leachate treatment with different electrochemical methods, (iv) recent advances, (v) merits, and demerits and (vi) proposal of future scope and the studies needed. The integration of electrooxidation with other treatment processes and the challenges hindering widespread adoption are also addressed. Overall, electrooxidation demonstrates promise as an effective and sustainable method for managing landfill leachate. Consequently, this article directs chacurrent and future research efforts toward optimizing the leachate treatment through electrooxidation techniques.

Heavy metal (HM) pollution has been a significant issue for the environment and public health. Unmonitored industrial effluents are a major source of HM pollution. However, metallotolerant bacteria thriving in such environments could be potentially useful for bioremediation purposes. In this study, Bacillus cereus IEI-01 was isolated from water samples of Badshahpur Lake, Gurugram, showcasing resilience to HM exposure and thriving under optimal conditions at 37°C and pH 7.0. Morphological and biochemical characterization showed its Gram-positive rod shape and metabolic versatility, including glucose fermentation and nitrate reduction capabilities. Molecular analysis further affirmed its close relation to the Bacillus cereus strain. Dynamic bacterial growth patterns were observed, with typical sigmoidal curves indicating significant growth over 72 h. When exposed to various HMs, the strain IEI-01 exhibited differential tolerance and promoting patterns, with cadmium (Cd) and lead (Pb) compared to other metals. Over 72 h, the strain exhibited substantial removal rates ranging from 60.64% to 87.43% for Cd and 41.87% to 52.62% for Pb. The concentration-dependent bio-removal efficiency of IEI-01 in Cd-spiked cultures displayed a declining trend with increasing concentrations, with removal rates ranging from 80.23% to 60.72% over the same period. These findings highlight the potential of Bacillus cereus IEI-01 for HM bioremediation, particularly at lower concentrations. Its efficacy in removing Cd and Pb from contaminated environments suggests promising applications in environmental cleanup efforts.

Exploration of microbial flora in red mud ponds is a topic of economic importance. In this study, we report two bacterial strains isolated from red mud ponds of Utkal Alumina, Odisha India. These strains were identified to be Brevundimonas sp. and Pseudomonas sp. through 16S rDNA analysis which showed more than 99% similarities with their respective clades. The LD50 values showed metal resistance to As, Cr, Cu, and Pb in a range of 2-8 mM. Both the strains showed a high tolerance towards arsenic and lead but a low tolerance towards chromium and copper salts. The bioaccumulation of copper was found to be the maximum and that of arsenic was the minimum. To find out the underlying genetic mechanism of the metal tolerance, a degenerate PCR approach was made to find out the genes responsible for the metal efflux or transformation. Two putative arsB genes could be identified from these two strains. Phylogenetic analysis of deduced amino acid sequences showed similarities with the amino acid sequences of arsB genes of Pseudomonas strains and formed monophyletic clades with their arsB proteins. These strains thus harbor potential genetic mechanisms for metal tolerance. Determination of whole operons and their cloning is the future aspect of the study. Moreover, these bacterial strains have a high potential to accumulate copper and can be used in studies related to biomining of copper.

The rapid increase in heavy metal accumulation within soil ecosystems has become a significant concern due to various anthropogenic activities such as industrial processes, agricultural practices, and urbanization. These activities have led to elevated levels of heavy metals like lead, cadmium, mercury, and arsenic in the soil, which, when surpassing permissible limits, pose severe toxicological risks to both human health and plant life. Once heavy metals are introduced into the soil, they can be readily absorbed by plants, subsequently entering the food chain and affecting the metabolic activities of humans and animals consuming these contaminated plants. Although trace amounts of heavy metals are naturally present in the soil, their concentration beyond safe thresholds can lead to deleterious effects, including disruption of enzymatic functions, damage to cellular structures, and interference with essential biological processes. Studies have highlighted that children living in urban and industrial areas are particularly vulnerable to heavy metal exposure, which can result in cognitive impairments, developmental delays, and various other health issues. Furthermore, long-term exposure to these metals can lead to chronic diseases such as cancer, kidney dysfunction, and cardiovascular disorders. Given the escalating threat posed by soil metal contamination, it is imperative to implement stringent management practices aimed at maintaining soil chemistry within safe limits. These practices may include the remediation of contaminated sites, the adoption of sustainable agricultural methods, regular monitoring of soil quality, and the use of phytoremediation techniques to mitigate the impact of heavy metals. Ensuring the safe production of food requires a comprehensive understanding of soil dynamics and the integration of innovative strategies to prevent and control heavy metal pollution. Consequently, addressing this environmental challenge is crucial for safeguarding public health, preserving ecological balance, and promoting sustainable development.

This study aims to develop a comprehensive flood hazard map for effective hazard management in the Noa river basin, located in Assam, India, through the integration of Geographic Information System (GIS) tools and a Maximum Entropy (MaxEnt) model. The MaxEnt machine learning algorithm was employed, utilizing eight selected geographic and environmental parameters as predictors to generate the flood hazard map. The accuracy of the generated map was evaluated using the Area Under the Curve (AUC) metric. Key findings of the study identified elevation and slope as critical parameters in the assessment of flood risk. Results revealed that the flood hazard map produced by the MaxEnt model achieved an AUC value of 0.85, indicating high predictive accuracy. The research underscores the significance of flood hazard maps as essential tools for policymakers, enabling the identification of areas vulnerable to severe environmental and economic damage. By providing a reliable and precise assessment of flood-prone zones, this study contributes valuable insights for the formulation of effective flood management strategies and mitigation measures. The implementation of such hazard maps is crucial in enhancing preparedness and resilience against flooding events, ultimately safeguarding lives, property, and infrastructure in the Noa River basin.