Anaerobic digestion (AD) of industrial wastewater has drawn researchers’ attention due to biofuel’s recovery in the form of biomethane. This study introduced two anaerobic semi-continuous reactors (ASCR)- R1 and R2 for bioremediation of the rice mill wastewater (RMWW). The alkali treatment of the substrate in reactors R1 and R2 was done by dry NaOH and Ca(OH)2, respectively. Both reactors were loaded with 80% of the RMWW and 20% of the cow-dung-fed biogas plant sludge (BGPS) for 16 days of stabilization at mesophilic temperatures (18℃ to 42℃). A small amount of jaggery and white rot fungi (Phanerochaete chrysosporium) were also added into both reactors for the bacterial growth and removal of the biorefractory organics (lignin and phenol) present in RMWW, respectively. The impact of variations in the hydraulic retention time (HRT) and organic loading rate (OLR) upon the anaerobic biodegradation of RMWW was studied in three operating phases (OP) I, II, and III. The highest BOD, COD, lignin, and phenol removal achieved in reactors R1 and R2 were 94%, 92%, 84%, and 82%, as well as 93%, 91%, 82%, and 80%, respectively, in OP I. The highest biomethane yield in both reactors was 0.005 L.g-1 COD in OP II. The results of the three operating phases reveal that a high HRT and low OLR give the maximum pollutant removal efficiency and the highest biomethane yield. The novelty of this research paper is the significant removal of the biorefractory organics lignin and phenol from the RMWW with the help of white rot fungi and specific bacterial strains Bacillus sp., Pseudomonas sp., Enterobacter sp., Actinomycetes sp. and Streptomycetes sp. present in the inoculum. The digestates from reactors were rich in macro and micronutrients viz., N, P, K, Cu, Zn, Fe, etc., essential for plant growth.

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.

Water conservation and management are significant features of ancient Indian Vedic culture. However, India’s rapid industrialization, globalization, and urbanization have posed a serious threat to this practice. Many metropolitan cities and other cities will likely have groundwater depletion in the near future. As per the ‘United Nations University - Institute for Environment and Human Security (UNU-EHS)’ report titled “The 2023 Interconnected Disaster Risks Report”, India is close to reaching its tipping point of groundwater depletion. It also highlighted that 27 of 31 major global aquifers are depleting faster than they can be replenished. A combination of factors, including climate change, private land ownership, mechanical pumping, etc., led to the depletion of groundwater and water scarcity for farming and other purposes. Additionally, NITI Aayog and the Central Water Commission have released several reports that highlighted the plight of the country’s aquifers. India’s groundwater resources are not only a potential source for agricultural, domestic, and industrial needs in the country but also a threat to its sustainable development and equitable distribution. At present, there is no central law on the groundwater regulation. Although the Model Groundwater (Sustainable Management) Bill 2017 is an affirmative step, its effectiveness depends on implementation by state governments, the establishment of robust local institutions, and removing political incentives from groundwater management. Until now, landowners have enjoyed monopolistic access to groundwater due to common laws that recognize uncontrolled rights over the resources. These restrictions have perpetuated gross inequities in accessing groundwater, which makes a remarkable shift from previous laws. This paper evaluates India’s existing groundwater laws to achieve sustainability, equity, and the effective execution of water rights. It also delves into the lacunae in the existing laws and suggestive measures to control the challenges of groundwater in India.

The present paper reports the results of experimental investigations performed to examine the feasibility of using fly ash (FA) and ground-granulated blast furnace slag (GGBS) geopolymers as barrier materials for waste containment facilities. The alkaline geopolymer is a blend of FA and GGBS with sodium hydroxide in concentrations varying from 1 to 5. The important properties of most barrier materials include strength and hydraulic conductivity. While FA can develop compressive strength through pozzolanic reactions, polymerized FA develops tensile strength. For the construction of barriers for landfills with higher heights, tensile strength assumes importance. To further improve the strength, FA can be amended with GGBS. Results indicate that the FA-GGBS mixture in the ratio of 40:60, when cured, exhibited higher strength at any molar concentration. Further, the hydraulic conductivity of the material, which is predominant for barriers in waste containment facilities, is studied. To examine the impact of the presence of heavy metals in the leachates, batch adsorption studies were executed on a 40% FA- 60% GGBS mixture. Leachate with nickel and lead were adapted for their retention within the barrier. It has been observed that the geopolymerized FA and GGBS can retain ionic metals. The retention capacity of heavy metals is due to their precipitation in the voids of the barrier material enabling further reduction in the hydraulic conductivity making geopolymer a sustainable barrier material.

Aphids are important insect pests and are considered a major threat to various crops. In the laboratory experiment, our objective is to assess the toxicity level of some newer synthetic insecticides, viz. Imidacloprid, Flonicamid, and Spirotetramat against different species of aphids viz. maize leaf aphids (Rhopalosiphum maidis), green peach aphids (Myzus persicae), and mustard aphids (Liphaphis erysimi). The leaf dip bioassay was conducted to evaluate the LC50 and LT50 values. Among these novel molecules, Spirotetramat was the most toxic insecticide against R. maidis and M. persicae, with median lethal concentrations (LC50) of 0.68 and 3.99 ppm, and Flonicamid was the most toxic against L. erysimi with an LC50 value of 5.79 ppm. The median lethal concentrations for the Imidacloprid, Flonicamid, and Spirotetramat are different for each species of aphids. The LT50 values of the given insecticides revealed that the Imidacloprid has the potential for giving effective control of R. maidis, M. persicae, and L. erysimi species, as evidenced by the shorter time required for 50% mortality with LT50 values of 44.53, 49.19 and 44.90 hrs respectively with median lethal concentrations of 4.20, 5.14 and 10.86 ppm. The results indicated variations in toxicity among these different chemicals against different insect species.

Natural disasters are natural activities that can disrupt various aspects. Natural disasters cannot be avoided, but the impact of natural disasters can be minimized through mitigation. This can be known through event history to determine an area’s vulnerability to natural disasters. This research aims to determine regional natural disaster vulnerability by calculating the natural disaster index. The data used in this research refers to data from the 2021 PODES data collection, which contains the intensity of natural disasters and casualties according to the type of natural disaster in Indonesia in 2020. The method used for the calculation is the weighted index method. The results of this research produced 5 clusters based on the level of natural disaster vulnerability according to sub-district/village. The top five provinces in Indonesia that have the highest natural disaster-prone areas are Aceh, North Sumatra, West Java, East Java, and Central Sulawesi. Research shows that sub-districts/villages in Indonesia are known according to their level of vulnerability to natural disasters. These results can be used as a reference for the government to carry out mitigation so that accelerated development in the local area can continue.

The present study aimed to investigate the bio-oil from the blended citrus fruit peel by hydrothermal liquefaction process. Huge amounts of fruit peel waste are disposed of in the open environment without any proper management. Such fruit peels are considered a potential bio-resource to be converted into economically valuable products like bio-oil. Since the citrus fruit peel is a rich source of moisture content, a hydrothermal liquefaction process was introduced to produce bio-oil from cellulose, and lignocellulose. The experimental design against temperature, time, and biomass concentration optimization was carried out which was confirmed by the ANOVA f and p test that reveals time and temperature influenced the bio-oil yield drastically. As the time and temperature rise more than 60 min and 280°C, the volatile substance present in the biomass converts itself into solid residue which has a negative impact on bio-oil production, compared with biomass concentration. The maximum yield of bio-oil was recorded as 29.4% at 280°C at 60min reaction time and 80g/200mL concentration as optimized parameters. The GCMS reveals the presence of hydrocarbons and alkanethiol which are flammable and hold the standards of commercial transportation fuel but hold nitrogen and oxygen-containing compounds to pull down the fuel standards. Thus, the produced bio-oil can be blended with the transportation fuel after the upgradation process for efficient results.

Microplastic pollution has become a global concern with potentially severe environmental and health implications. This research explores the level of knowledge and awareness about microplastics among the urban population of Pune, a busy city in India. A mixed-methods approach was employed using a sequential explanatory design. In the first phase, qualitative data were gathered through semi-structured interviews with 18 participants selected via purposive sampling. In the second phase, quantitative data were collected from 100 participants using a survey and convenience sampling. By combining insights from surveys, interviews, and existing literature, the study analyzed the extent to which residents of Pune are informed about microplastic pollution and their willingness to take action. The findings highlight the need for increased awareness campaigns and educational initiatives to address the growing microplastic problem in urban areas. The study concludes that plastics have become an integral part of our lives, necessitating robust mechanisms to eliminate them from daily use.