Municipal Solid Waste Dumpsite Research Articles

Assessment of Ambient Water Quality Deterioration in Proximity to Municipal Solid Waste Dumpsites in Urban Areas of Chattogram, Bangladesh

This study aims to assess the impact of waste dumping on groundwater quality within the Chattogram City Corporation area. Monitoring eight groundwater sampling points over four years, various physical and chemical parameters were analyzed, utilizing the APHA method. Parameters assessed include pH, temperature, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDS), salinity, biological oxygen demand (BOD), chemical oxygen demand (COD), Turbidity, Total Hardness, Ca-Hardness, Alkalinity, TSS, Chloride, Phosphate, Sulphate, Nitrite, Nitrate, Fluoride, Iron, Arsenic, Zinc, Copper, and Chromium. The findings were compared to the Department of Environment's (DoE) recommended values, as well as the Bangladesh standard and World Health Organization (WHO) values. During sample collection, deep tube wells near the dumping site points were prioritized. According to the investigation CNB, Ananda Bazar Halishahar and Arefin Nagar, deep pump water carries too many irons in their groundwater. Iron levels exceed both WHO and Bangladesh standards across all samples. Specifically, Arefin Nagar and Ananda Bazar Halishahar area sampling points S6, S7, and S8 surpass standards in TDS, Total Hardness, Turbidity, TSS, Chloride, and Iron. Water Quality Index (WQI) calculations suggest unsuitability for drinking purposes in all sampled water, with S5 and S8 demonstrating particularly high values, indicating their unsuitability for human consumption. Heavy Metal Pollution Index (HPI) calculations reveal a decrease at CNB sampling points S1 and S2, where waste dumping ceased in 2017. However, HPI values at other points show an increasing trend, indicating the leaching of heavy metals from solid waste into groundwater. S5 and S8 exhibit notably high HPI values (Average 464.99 and 319.59), suggesting an accumulation of heavy metals in the groundwater. Carcinogenic Risk Analysis of Arsenic highlights the failure of most sampled water to meet Carcinogenic Risk (CR) standards, signalling a potential cancer risk with prolonged use of this water.

Arthropod Diversity of Municipal Solid Waste (MSW) in Ebonyi Waste to Wealth Company Abakaliki Ebonyi State, Nigeria

The study was designed to determine the diversity of arthropods in Ebonyi State waste to wealth Abakaliki, a municipal waste site (MWS) in Abakaliki where solid wastes of all sorts are deposited. The arthropod specimens were analysed using standard entomological technique of sweep net, pitfall traps and malaise trap respectively. Arthropod species identification was done morphologically at insect Museum Ahmed Bello University in Zaria. A total of 2000 arthropod specimens were collected comprising 8 orders, 18 families and 28 species. The most abundant species in diversity is Bengalia gallard 208 (10.4) followed by Musca domestica 205(10.2). Out of the 2000 individual species of arthropods collected from MSW dump site in Abakaliki, Diptera (48.30) and Hymenoptera (39.12) were the most prevalent while Dermaptera were the least in abundance. Four insect species were heterometabolic including medically important species, Blattela sp. (Blattodea). Insect Order Diversity in Respect to traps used for collection showed that pitfall trap with the total of 854 insects recorded the highest and Hymenoptera (43.2) recording the highest frequency. Shannon Weiner's Diversity Index of Insect Orders revealed that Diptera (0.48) had the highest diversity. Determination of the arthropod diversity in MSW will help in the control of possible vector borne disease epidemics especially in areas where there is no awareness of disease to its vector transmission.

Geoenvironmental Assessment of the Impacts of Ewu-Elepe Dumpsite on Soil and Groundwater Resources at Ikorodu, Lagos State, Nigeria

The environmental status of the municipal solid waste dumpsite at Ewu-Elepe, Ikorodu Local Government Area of Lagos State was  investigated. A total of seventeen (17) samples consisting of twelve (12) soils, three (3) groundwater and two (2) leachate samples were  collected and analyzed for different parameters using Atomic Absorption Spectrophotometer (AAS). The results revealed that in the  leachate samples, all the heavy metals, Cl- , COD, salinity, and conductivity contents showed significant increase. The physicochemical  results for the groundwater samples agreed with the international standards for drinking water, except for high cadmium content  (0.009mg/l) recorded in the groundwater sample W1 which exceeded the NSDWQ and WHO permissible limits of 0.003 and 0.005mg/l  respectively for drinking water, and high manganese content (0.09mg/l) recorded also in W1. The results of soil samples from the  dumpsite showed that the concentration of all the heavy metals, Zn (23.5mg/kg), Cu (10.8mg/kg), Cr (14.2mg/kg), Ni (3.47mg/kg) and Pb  (19.0mg/kg) fall below the Sediment Quality Criteria ISQG-Low level and the Lowest Effect Range of the New York Sediment Criteria  except for Cd (16.60mg/kg) which is even higher than the High Effect Range of both the New York sediment Criteria and the Sediment  Quality Criteria that the soil within the dumpsite have been moderately impacted is further demonstrated by the application of  environmentric parameters treatment such as Contamination Factor (CF), Geo-accumulation Index, Enrichment Factor (EF) and Ecological  Risk Factor Analyses. The results of the sediment quality assessment are good evidence to confirm that the soil of the  dumpsite is highly polluted with cadmium (Cd), and moderately contaminated with lead (Pb). This study reveals that the solid waste  dumpsite is affecting the natural quality of the ambient environment. Therefore, indiscriminate dumping of solid waste at the dumpsite   should be prohibited.

Human and Ecological Risk Assessment of Soil and Plants Metal Contamination in a Tropical Municipal Solid Waste Dumping Site

ABSTRACT The growing open waste dumpsite contributes to heavy metal leaching, harming public health and ecosystem services. Hence, the study’s novelty lies in its integrated assessment of heavy metal concentration (Cd, Cr, Cu, Fe, Ni, Pb, and Zn) in soil and plants, incorporating risk assessment using both single and combined indexes in the largest active waste dumpsite in Kelantan, Malaysia. Heavy metal in soil samples Cu (164.896 ± 205.096), Pb (122.177 ± 93.309), and Cr (32.74 ± 26.569) were recorded to exceed the standards, while in the studied plants (castor bean, papaya, pea eggplant, and water spinach), Pb concentrations in all plant parts have surpassed the Malaysia Food Regulation (1985) and FAO/WHO guidelines (2016). Translocation factor (TF) in Cu, Cr, and Pb in water spinach and Cr, Cu, and Cd in pea eggplant have TF > 1. Bioconcentration factor (BCF) was < 1 in pea eggplant and water spinach except for Pb in pea eggplant. Correlation analysis revealed a strong correlation between heavy metals in the soil while contrasts in the plants. The potential ecological risk index (PERI) reveals that the soil waste dumpsite is contaminated with heavy metals. The hazard index (HI) and lifetime cancer risk (LCR) values of heavy metals on the soil surface had negligible non-cancer risks posed to adults and indicate that soil ingestion and dermal absorption were the two primary carcinogenic risk exposure routes. These findings implied that Beris Lalang waste dumpsite is a potential source of toxic pollutants to the environment and the local population. It is recommended to conduct a comprehensive feasibility study and design an implementation plan for leachate treatment plant. Additionally, a comprehensive assessment of the specific contaminants present in the leachate and their potential impacts on the environment should be conducted to inform targeted and effective treatment strategies.

Isolation and characterization of Cr(VI) reducing Mammaliicoccus sciuri jv5 from municipal solid waste dumpsite soils

Cr(VI) is one of the most widely used elements in various industrial sectors and, hence, extensively found as a toxicant in the ecosystem. The biotransformation of Cr(VI) via microorganisms is considered an ecofriendly approach for its detoxification. The present study focused on the isolation of an indigenous bacterium from municipal solid waste dumpsite soils with relatively higher Cr(VI) resistance (>1000 mg L−1 in broth) and a 97% reduction of Cr(VI) (100 mg L−1) under conditions of 37 °C, pH 7, and 120 rpm in 48 h. The biochemical and 16 S rRNA gene sequencing showed that the isolate exhibits 99% similarity with Mammaliicoccus sciuri. Partial reductase gene sequences were retrieved, showing 96% similarity to NADPH-dependent FMN reductases. Fourier transform infrared spectroscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy showed the presence of Cr products on bacterial cells. X-ray photoelectron spectroscopic analysis confirmed the valence state of the residual Cr present as Cr(III). Furthermore, quantitative localization of reduced Cr products and transmission electron microscopic analysis confirmed the intracellular accumulation of the Cr(III). A multifaceted mechanism, including surface adsorption and bioaccumulation after biotransformation, confers a potential solid identity for the strain Mammaliicoccus sciuri jv5 toward Cr(VI) remediation in the Cr polluted environment niche.

Isotopic tracing of leachate percolation from municipal solid waste dump sites to groundwater in diverse climatic zones of India.

Groundwater resources in tropical regions are largely dependent on recharge by rainwater infiltration through soil layers with variable time. However, the rainwater infiltration through soil is a serious concern in urban tropics where it interacts with landfills at the dumpsites, potentially contaminating adjoining groundwater. In this study, the stable isotopic compositions of oxygen and hydrogen (δ18O and δ2H, respectively) in groundwater and leachates, adjoining municipal dumpsites in urban tropics (Bangalore, Kolkata and Durgapur located in diverse rainfall zonation of India), were analyzed to investigate their recharge sources and trace the possible mixing of leachate contaminants under three diverse climatology. The measured values of δ18O and δ2H suggested that the groundwater in these sites reflects higher recharge by rainwater. However, the d-excess values indicated secondary effects suggesting the groundwater has experienced significant modifications. The end member analysis using δ18O-d-excess relation pinpointed an additional leachate contribution from adjoining dumpsites. The critical fraction of leachate infiltration to groundwater quantified using two component mixing model ranged between (i) 1 and 33% in Bangalore, (ii) 5 and 13% in Kolkata and (iii) 18 and 76% in Durgapur, with its variability dependent on seasonality and aquifer connectivity. This information is crucial for groundwater management to secure water quality and to quantify potential hydrological contaminants particularly in drier seasons and drier regions, when and where the demand for groundwater is high, respectively.

Exploring genetic landscape of low-density polyethylene degradation for sustainable troubleshooting of plastic pollution at landfills

Plastic pollution increases globally due to the high volume of its production and inadequate mismanagement, leading to dumps in landfills affecting terrestrial and aquatic ecosystems. Landfills, as sink for plastics, leach various toxic chemicals and microplastics into the environment. We scrutinized the genetic expression for low-density polyethylene (LDPE) degradation via microorganisms to investigate cell viability and metabolic activities for biodegradation and genetic profiling. Samples were collected from the Pirana waste landfill at Ahmedabad, Gujarat, which is one of the largest and oldest municipal solid waste (MSW) dump sites in Asia. Results analyzed that isolated bacterial culture PN(A)1 (Bacillus cereus) is metabolically active on LDPE as carbon source during starvation conditions when incubated for up to 60 days, which was confirmed via 2,3,5-triphenyl-tetrazolium chloride (TTC) reduction test, reported cell viability and LDPE degradation. Abrasions, surface erosions, and cavity formations were analyzed via scanning electron microscopy (SEM), whereas the breakdown of high molecular polymers converted to low molecules, i.e., depolymerization, was also observed via Fourier-transform infrared (FTIR) spectroscopy over 90 days, along with changes in functional groups of carboxylic acids and aldehyde as well as the formation of polysulfide, aliphatic compounds, aromatic ethers, alcohols, and ether linkages. Further, transcriptomic analysis was performed via DESeq2 analysis to understand key gene expression patterns and pathways involved in LDPE degradation. During the initial phase of LDPE degradation, genes related to biological processes, like membrane transportation, ABC transporters, carbon and lipid metabolism, fatty acid degradation/oxidation, and TCA cycle, are likely to indicate pathways for stress response and molecular functions, like oxidoreductase, catalytic, lyase, transferase, and hydrolase activities were expressed. Interlinking between metabolic pathways indicates biodegradation process that mineralizes LDPE during subsequent incubation days. These pathways can be targeted for increasing the efficiency of LDPE degradation using microbes in future studies. Thus, considering microbial-mediated biodegradation as practical, eco-friendly, and low-cost alternatives, healthy biomes can degrade polymers in natural environments explored by understanding the genetic and enzymatic expression, connecting their role in the process to the likely metabolic pathways involved, thereby increasing the rate of their biodegradation.

Characterisation of Waste and Assessment of Surface Methane Emissions by Static Chamber Technique at a Major Dumping Site in Central India

Given the vast amount and higher organic content of waste generated by developing nations such as India, as well as the challenges related to waste management and global warming, controlling methane emissions from such municipal solid waste (MSW) dumpsites becomes a major concern. As a result, studying the characteristics of solid waste dumped and the subsequent emissions of methane (CH4) from a site lacking proper disposal and gas emission management facilities, as is common in developing countries, becomes more important for suggesting appropriate corrective measures. In this study, MSW samples were collected from the Bhandewadi dumping site, a prominent site in Nagpur city and subjected to proximate, ultimate, and biochemical analysis. The results showed that the waste had high moisture content due to the tropical climate of the region which, together with the greater carbon content and organic matter (OM), may be responsible for increased overall greenhouse gas emissions. Biochemical study, on the other hand, revealed lower lignin content when compared with cellulose and hemicellulose, which are key contributors to CH4 emissions. The actual on site measurements using static chamber technique at fresh dumping sites showed that the methane (CH4) flux was between 1 and 14.3 mg m-2 sec-2 and 0.9 to 7.11 g m-3 day-2 at old dumping areas. The study contributes to a better understanding of the amount and unpredictability of methane produced by solid waste in an unmanaged dumping site.

Groundwater quality in the vicinity of a dumpsite in Lagos metropolis, Nigeria

Inappropriate management of municipal solid waste dumpsites is a major cause of groundwater contamination in developing countries, but the extent of the problem is not known. This study investigated groundwater quality in the vicinity of Olusosun dumpsite in Lagos, Nigeria, the most populous city in sub-Saharan Africa. During 2020, monthly groundwater samples were collected in 17 wells and boreholes used as drinking water sources, and analysed for 20 physico-chemical parameters. Differences between sites and seasons were statistically assessed, together with changes in water quality index (WQI). The results indicated that heavy metals (Pb2+, Ni+, Mn2+, Fe2+, Cr6+), cations (Ca2+, Mg2+, K+), total hardness and pH were the main parameters impairing water quality. Drinking water quality standards from both the World Health Organization and Nigeria government were exceeded more often in the wet season than in the dry season. Some groundwater properties were negatively correlated with distance to dumpsite (e.g., Fe2+, Pb2+, NO3−). Significant differences between sites were identified, but with no clear spatial trend. WQI varied from excellent (6%–24% of the sites over the study period) to unsuitable for drinking water purposes (12%–18%), with good quality prevailing at most sites (35%–47%). Although groundwater quality declined at 24% of the sites over 2020, the results indicated improvements compared with previous decades. Remediation strategies must be implemented to safeguard public health and the sustainability of water resources.

Passive fungal spore release from fruit and vegetable solid waste

Food substrates in municipal solid wastes processing facilities and open dumpsites are a source for the release of fungal spores into air and can cause potential health and climate effects. Experiments were conducted in a laboratory scale flux chamber to measure the fungal growth and spore release from representative exposed cut fruit and vegetable substrates. The aerosolised spores were measured using an optical particle sizer. The results were compared to experiments conducted previously with a test species (Penicillium chrysogenum) on a synthetic media (czapek yeast extract agar). Significantly higher surface spore densities were observed for the fungi on the food substrates as compared to that on the synthetic media. The spore flux was high initially and then decreased on continued exposure to air. The spore emission flux normalised to the surface spore densities indicated that the emission from the food substrates was lower than the emissions from the synthetic media. A mathematical model was applied to the experimental data and the observed flux trends were explained in terms of the model parameters. A simple application of the data and the model to release from a municipal solid waste dumpsite was shown.

Environmental Impact of Wasteyard Leachate Pollution, It’s Health Risks with Some Microbial and Ecological Implications

The study was carried out to assess the public health risks from the consumption of farm crops and vegetables cultivated around active municipal solid waste dumpsites in Delta State. Using the experimental research method soil and vegetation (cassava leaves) samples were collected from ten spatial locations around municipal solid waste dumpsites (SWD), scrap metals yards (SMY) and agricultural farms and subjected to laboratory analysis of relevant physic-chemical parameters. Heavy metals like cadmium “Cd”, iron “Fe”, nickel “Ni” and lead “Pb” concentrations including, total variable bacteria (TVB) and Salmonella spp load in collected samples were determined in accordance with standard procedures. The results revealed a substantial spatial dispersion of the heavy metals, TVB and Salmonella spp concentrations within the two study areas. Remarkably, the bacteria level was higher in the SWD than in the SMY while the heavy metals concentration was higher in the SMYs when compared to the SWD. Spatially, soil and vegetation around the SMD area had higher HMs’ Hazard quotient, Hazard index and Carcinogenic risk values, when compared to the soil around the SMY region, but all their status were within safe limits for the human health. Salmonella spp population in the SWD and SMY soil ranged from 1.33 to 39.33 cfu/g of dry soil and 1.04 to 8.67 cfu/g of dry soil respectively while the TVB count ranged from 6233 cfu/g to 46500 cfu/g of dry soil. Although the heavy metal contamination levels in the soil samples were within safe limits, the presence of the pathogenic bacterium in the soil pose health threat to the inhabitants of the regions.

An investigation on mobility of heavy metals for assessing the reusability of soil-like material reclaimed from mining of municipal solid waste dumpsites

Landfill mining, often referred to as “bio-mining”, enables the recovery of resources, including combustible, compostable, and recyclable fractions from landfills. However, most of the materials mined from old landfills mainly consist of soil-like materials (SLM). The reuse of SLM depends on the concentration of contaminants, such as heavy metals, soluble salts, etc. A sound risk assessment requires sequential extraction to determine the bioavailability of heavy metals. This study focuses on the mobility and chemical speciation of heavy metals in SLM from four old municipal solid waste dumpsites in India by performing selective sequential extraction. Additionally, the study compares the results with those of four previous investigations to identify international similarities. It has been observed that Zn was mainly available in the reducible phase (average 41%), whereas Ni and Cr proved to have the highest distribution in the residual phase (64% and 71%, respectively). Pb analysis showed a large portion in the oxidizable phase (39%), while Cu was mainly present in the oxidizable (37%) and residual (39%) phases. Similarities with previous investigations were observed for Zn (primarily reducible 48%), Ni (residual 52%), and Cu (oxidizable 56%). Correlation analysis showed that Ni correlated with all heavy metals (ρ = 0.71–0.78), except with Cu. The present study suggested that Zn and Pb are associated with a high risk of pollution due to their maximum distribution in the bioavailable phase. The findings of the study can be used to assess the heavy metal contamination potential of SLM prior to its reuse in offsite applications.

Mathematical modeling and numerical simulation technique for selected heavy metal transport in MSW dumpsite

The study focused on development of mathematical modeling and numerical simulation technique for selected heavy metal transport in Uyo municipal solid waste dumpsite in Akwa Ibom State to investigate the level in depth to which leachate from the dumpsite extends and the quantity of leachate at various depth of the dumpsite soil. Uyo waste dumpsite is operating open dumping system where provisions are not made for preservation and conservation of soil and water quality, hence, the need for this study. Three monitoring pits within Uyo waste dumpsite were constructed and infiltration runs were measured, and soil samples were collected beside infiltration points from nine designated depths ranging from 0 to 0.9 m for modeling heavy metal transport in the soil. Data collected were subjected to descriptive and inferential statistics while the COMSOL Multiphysics software 6.0 was used to simulate the movement of pollutants in the soil. It was observed that heavy metal contaminant transport in soil of the study area is in the power functional form. The transport of heavy metals in the dumpsite can be described by a power model from linear regression and a numerical model based on finite element. Their validation equations showed that the predicted and the observed concentrations yielded a very high R2 value of over 95%. The power model and the COMSOL finite element model show very strong correlation for all selected heavy metals. Findings from the study has identified level in depth to which leachate from the dumpsite extends and the quantity of leachate at various depth of the dumpsite soil which can be accurately predicted using leachate transport model of this study.

Surface emission determination of selected trace gases from an active municipal solid waste dumpsite under the surface physicochemical heterogeneity.

Karadiyana municipal solid waste (MSW) dumpsite in Colombo, Sri Lanka, has been in operation for over 30years and was evaluated for its surface Volatile Organic Compounds (VOCs), Ammonia (NH3), and Hydrogen sulfide (H2S) emissions. Based on the surface conditions and waste characters, the dump surface was divided into eight cells, and multiple samplings were done using static flux chamber methods. The study observed that the average flux rates of VOCs, H2S, and NH3 were 137.2±243.8, 6.63±15.9, and 14.2±16.2mgm-2h-1 throughout the dump site. The highest average VOCs and H2S flux rates (828.6, 24.3mgm-2h-1) were reported from new organic waste with a considerable fraction (62.5, 35.6%) from the total emission (61.0, 3.1 Kg d-1). Leachate-flowing trenches produced the highest NH3 flux rate (36.0mgm-2h-1), while the highest emission fraction (47.5%) from the total (12.0 Kg d-1) was reported on old mixed waste with vegetation. The moisture content of the organic waste layers is positively correlated with these trace gas flux rates, and the NH3 flux rates depend on the pH of the surface. Results showed that the age of the waste determines the trace gas emission rate, and leachate provides an ideal pathway for landfill trace gas migration to the atmosphere. Gas collection and purification systems are essential for the initial waste dumping area and leachate treatment system. The arrangement of a proper drainage system on the dump would reduce trace gas emissions.

Effect of expansive soils on swelling behavior of encapsulated sodium bentonite of geosynthetic clay liner (GCL)

Due to the rapid urbanization of Indian cities, the generation of MSW is exponentially increasing. The confinement of the hazardous emission from a municipal solid waste (MSW) dumpsite is the major responsibility of management and engineers. Landfill gases and leachate generation are the results of chemical and biological activities in municipal solid waste and its decomposition process. The seepage control of leachate is a crucial aspect of MSW management. The flow of leachate to groundwater is one of the major causes of groundwater contamination resulting in human health risks nearby population. Geosynthetic clay liners (GCLs) are the most preferred options to restrict the flow of leachate from dumpsite to groundwater. GCL consists of sodium/ calcium bentonite as an encapsulated material between woven and non-woven carriers. The swelling behavior of sodium bentonite with low hydraulic conductivity makes it suitable to prevent the flow through it. In this study, the swelling nature of sodium bentonite was assessed in combination with expansive soils. The soils were collected from two different regions of Uttar Pradesh as Banda and Mahoba districts. The results showed that the swelling tendency of sodium bentonite can be enhanced by using specific proportions of expansive soils.

Isolation and screening of low-density polyethylene (LDPE) bags degrading bacteria from Addis Ababa municipal solid waste disposal site “Koshe”

PurposeThis study aims to screen bacterial isolates from the Addis Ababa municipal solid waste dumping site (Koshe) for the biodegradation of low-density polyethylene bags and analyzes their efficiency in degrading plastic bags.MethodsIn this study, low-density polyethylene bag-degrading bacteria were isolated from the Koshe municipal solid waste disposal area in Addis Ababa, Ethiopia. Screening of isolates for low-density polyethylene bag biodegradation was carried out using a clear zone method. Additionally, the efficiency of the isolates for low-density polyethylene biodegradation was evaluated using the weight loss method, scanning electron microscopy analysis, and Fourier transform infrared analysis. Finally, molecular identification of potential low-density polyethylene degrader bacterial isolates was done by 16S rDNA sequencing.ResultsIsolates KS35, KS14, and KS119 resulted in significant weight loss of low-density polyethylene film (42.87 ± 1.91%, 37.2 ± 3.06%, and 23.87 ± 0.11% weight loss, respectively). These isolates were selected for further biodegradation study using scanning electron microscopy and Fourier transform infrared analysis. Scanning electron microscopy analysis shows the formation of pores, pits, and distortion of the plastic surface. Fourier transform infrared analysis indicates the appearance of new peaks at the surface of low-density polyethylene films. Phylogenetic analysis of the three potential bacterial isolates was also carried out, and the result indicates that the sequence of isolate KS35 had 99% similarity with sequences of Methylobacterium radiotolerans MN525302. Isolate KS119 had 100% similarity with Methylobacterium fujisawaense KT720189, and the sequence of isolate KS14 had 99% similarity with species of Lysinibacillus fusiformis.ConclusionsWeight loss, scanning electron microscopy analysis, and Fourier transform infrared analysis results show that isolates KS35, KS14, and KS119 have high potential in degrading low-density polyethylene bags.

Decoding the PLFA profiling of microbial community structure in soils contaminated with municipal solid wastes

This study aimed to assess the influence of municipal solid waste (MSW) disposal on soil microbial communities. Soil samples from 20 different locations of an MSW dumping site contaminated with toxic heavy metals (HMs) and a native forest (as control) were collected for phospholipid fatty acid (PLFA) profiling to predict microbial community responses towards unsegregated disposal of MSW. PLFA biomarkers specific to arbuscular mycorrhizal fungi (AMF), Gram-negative and Gram-positive bacteria, fungi, eukaryotes, actinomycetes, anaerobes, and microbial stress markers-fungi: bacteria (F/B) ratio, Gram-positive/Gram-negative (GP/GN) ratio, Gram-negative stress (GNStr) ratio and predator/prey ratio along with AMF spore density and the total HM content (Cu, Cr, Cd, Mn, Zn, and Ni) were assessed.The results showed that all of the PLFA microbial biomarkers and the F/B ratio were positively correlated, while HMs and microbial stress markers were negatively correlated. The significant correlation of AMF biomass with all microbial groups, the F/B ratio, and T. PLFA confirmed its significance as a key predictor of microbial biomass. With AMF and T. PLFA, Cd and Cr had a weak or negative connection. Among the toxic HMs, Zn and Cd had the greatest impact on microbial populations. Vegetation did not have any significant effect on soil microbial communities. This research will aid in the development of bioinoculants for the bioremediation of MSW-polluted sites and will improve our understanding of the soil microbial community's ability to resist, recover, and adapt to toxic waste contamination.

Analysis of the Uptake and Distribution of Heavy Metals in Sweet Corn Grown on Municipal Solid Waste Dumpsite Soil in Delta State, Nigeria

Analysis of the Uptake and Distribution of Heavy Metals in Sweet Corn Grown on Municipal Solid Waste Dumpsite Soil in Delta State, Nigeria

Leachate Characterization Generated from Municipal Solid waste at Landfill Site Ghazipur, New Delhi

Abstract: The management of municipal solid waste (MSW) is one of the key environmental issues facing Indian cities, mostly as a result of the country's growing industrialisation and urbanisation. According to numerous studies, open dumps and landfills are used to dispose of around 90% of solid waste in an improper manner. Pollutants can escape a poorly constructed landfill in a number of ways. Leachate can escape from a landfill or dumpsite and contaminate groundwater and surface water if the soil above or below it is porous. Therefore, In this paper an attempt is made to characterize the leachate produced by municipal solid waste dumping site of Ghazipur, New Delhi which is located at Latitude: 28° 37' 30.8784". Longitude: 77° 19' 40.764" near the Delhi-UP border. In this investigation, about 12 leachate parameters were identified. Three sample sites at the bottom of the landfill, spaced 7 metres apart, were used to characterise the leachate samples. All of the leachate samples had an acidic pH value ranging from 6.24 to 6.88, it is discovered. All of the sample’s conductivity and total dissolved solids ranged from 567 to 1945 S/cm and 513 to 1289 ppm respectively. Similar dissolved ions such chloride, calcium, sodium, nitrate, and potassium were found in the leachate sample. The majority of the ions were discovered to be above the standards-permitted level. The present study concludes that characterization of landfill leachate is important to identify the most critical pollutants present in the leachate and thereby to introduce suitable and applicable technologies such as in-situ impermeable barriers etc.

Isolation and identification of promising antibiotic-producing bacteria

Abstract Multiple stresses in waste dumpsite soils can drive antibiotic production as one of the strategies for survival. Bacteria are the most prolific producers of antibiotics. This study investigated the antibiotic production potential of bacteria isolated from Bahir Dar city municipal solid waste dumpsite (MSWDS). Bacteria were isolated from soil collected from the dumpsite on starch casein or nutrient agar. The isolates were carefully screened for antimicrobial activity against six pathogenic bacterial test strains. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also determined from cell-free metabolites of the most promising isolates. Isolates showing antimicrobial activity were identified using cultural and biochemical methods. A total of 143 distinctive colonies were obtained and tentatively identified to 13 bacterial genera. Twenty-six (18.18%) of the isolates (six Bacillus and 20 actinobacteria related) demonstrated antimicrobial activities at least against one of the tested bacterial strains. These isolates were related to two actinobacterial and 11 other bacterial genera. Seven out of 26 isolates showed a broad-spectrum of antibiotic activities. Two isolates, which showed a wide spectrum, were selected for the MIC and MBC tests against Escherichia coli and Staphylococcus aureus. The MIC and MBC of the isolates were recorded to be 250–500 µg/mL against the test strains. Bahir Dar city MSWDS contained a high incidence of antibiotic-producing bacteria. Strain level identification of the isolates and detailed characterization of the metabolites will give a good insight into the antimicrobial production potential in the waste dumpsite.