Waste Dumpsite Research Articles

Determination of Some Physicochemical Parameters of Soil in an Abandoned Waste Dumpsite in Rumuolumeni, Port Harcourt

This research work studied the levels of some physicochemical parameters such as pH, electrical conductivity, moisture content, organic carbon, organic matter, total nitrogen, total phosphorus and alkalinity of soil in an abandoned waste dumpsite in Rumuolumeni, Port Harcourt. Soil samples were collected at three different points within the abandoned waste dumpsite for the determination of the levels of the studied physicochemical parameters. The different physicochemical parameters studied were analyzed appropriate laboratory methods. The average range of values recorded for the different physicochemical parameters studied within the period of investigation in the abandoned dumpsite were; pH; 6.38±0.13 to 6.82±0.12, electrical conductivity; 879.69±17.67 to 1062.77±16.77 µS/cm, moisture content; 20.84±0.50 to 23.33±1.00%, % organic carbon; 4.55±0.04 to 5.46±0.13%, %organic matter; 7.85±0.06 to 9.42±0.23%, total nitrogen; 0.13±0.01 to 0.18±0.00%, total phosphorus; 1.30±0.05 to 2.18±0.02% and alkalinity; 5.75±0.06 to 7.98±0.22mg/Kg. The degree of occurrence of the investigated parameter in the abandoned waste dumpsite were within limits acceptable by FAO/WHO for agricultural soil. The results recorded indicated that even at this stage that there should be proper monitoring of waste dumpsites and that planting of crops should be discouraged so that human health will be preserved.

Optimal Urban Waste Dumping Site Selection in Kalutara DS Division of Sri Lanka using GIS-based Multi-Criteria Decision Analysis

Improper waste dumping is an emerging issue in Sri Lanka because of the unsystematic urbanisation process. The main problem of the study is determining sites that are ideal for waste dumping. The use of improper waste disposal methods adversely affects the environment and human lifestyle. This study focuses on integrating a structured approach under multi-criteria decision analysis for waste dumping. The present study has been carried out in Kalutara DS Division, integrating Analytical Hierarchy Process (AHP)-based Multi-Criteria Decision Analysis (MCDA) and geospatial techniques to find suitable waste dumping sites. Ten different types of criteria were selected for the study in vector and raster format, namely, land use, population density, schools, religious places, government offices, coastal areas, hospitals, roads, railways, and environmentally sensitive areas. After finalising the criteria, the GIS-based AHP-MCDA methodology was used for weighting, standardisation, and normalisation by obtaining the opinions of experts and conducting literature surveys. The results of the study are sorted into not-suitable, less-suitable, and suitable dumping sites. Classified suitability maps revealed that 36.94% are not suitable, 53.06% are less suitable, and completely 9.9% are suitable for urban waste dumping sites. The spatial variance of suitable and not suitable waste disposal sites was found in the north, north-eastern, and western and central parts of the study area. Hence, based on the results indicated using such methods, it will be an effective manual for engineers, regional planners, and decision-makers to implement sustainable waste management in the study area in the future.

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.

Applied potential assisted biodegradation of amoxicillin (AMX) using bacterial consortium isolated from a waste dump site

Antibiotics have revolutionized modern day living with their ability to effectively treat infectious diseases in humans and animals. However, the release of antibiotic compounds into the environment has led to toxic consequences. To reduce this environmental impact, it is important to employ an inexpensive and rational technology to reduce the amount of antibiotics released into the ecosystem. This study aims to explore the potential of using a bio-electrochemical system (BES) to remove Amoxicillin (AMX) from artificially contaminated soil using a microbial consortium and pure culture isolates. Under desired conditions, including an initial AMX concentration of 150 mg/L, 5 mg/L tryptone as the nitrogen source, pH of 7, temperature of 29 °C, an applied potential of 0.8 V, and an inoculum dose of 1% w/v, the BES showed a maximum degradation of 97.9% of AMX with the microbial consortium (HP03, HP09, and HP10). High performance liquid chromatography-mass spectrometry was used to analyse the intermediates formed during the degradation process, and the pathway elucidated revealed complete degradation of AMX. Phytotoxicity studies and degradation efficiency against multiple antibiotics confirmed the environmental significance of the BES with microbial consortium. Overall, this study highlights the potential of BES as a cost-effective and efficient method for reducing the release of antibiotics into the environment and provides valuable insights into the mechanisms and pathways of antibiotic degradation.

Degradation and decolorization of textile azo dyes by effective fungal-bacterial consortium.

Synthetic dyes are one of the main pollutants in the textile industry and bioremediation is considered as an environmentally friendly method to degrade them. Soil microbial consortia (MCs) are reported having the potential of decolorizing most of textile dyes. This study aimed at evaluating dye-degrading ability of MCs developed from fungi and bacteria. Fungi and bacteria were isolated from the soil samples obtained from textile waste dumping site at Horana industrial zone, Sri Lanka and were screened for crystal violet (CV) and congo red (CR) dyes to develop MCs. Decolorization assay was performed for MCs along with individual isolates under variable pH levels. Metabolized products were characterized to confirm the biodegradation. A. tamari (F5) and P. putida (B3) significantly (P < 0.05) decolorized both dyes. All the MCs showed higher decolorization percentages over the individual microorganisms. Neutral pH (pH 7) was the optimum pH for the decolorization of both dyes by individual isolates and the percentages were significantly changed under the acidic and basic pH levels. However, decolorization ability by all MCs was not significantly changed with pH. Consortium with A. tamari - P. putida significantly (P < 0.05) decolourized both dyes under optimum pH 7. All MCs showed better pH tolerance in degrading CV and CR. Thus, it can be concluded that the selected MC with A. tamari - P. putida can degrade CV and CR textile dyes efficiently into non-toxic compounds against plants under neutral pH. Degradation and decolorization of textile azo dyes by effective fungal-bacterial consortium.

Challenges of Public Participation in Solid Waste Management at Nkanfoa Landfill Site in the Cape Coast Municipality of Ghana

Public participation in waste management is considered a sustainable approach to waste management as such it should be embraced. In municipalities of developing countries like Ghana, public outcry over the wrong location of waste dumpsites and poor public interest in waste management has called for this study to understand how public participation contributes to efficiency in solid waste management. For those living close to waste dump sites, conditions including odour and smoke pollution are believed to be avoidable when the public participates in decision making on the location of waste dump sites. This study investigated challenges facing Nkanfoa community regarding their involvement in waste management decision making. A mixed method approach was used to gain an in-depth understanding of the challenges associated with public participation in solid waste management. The findings showed that the community members feel their concerns are not factored into the decision making process of the assembly as such a lack of trust between them and the municipal assembly. Also, there is the perception that political office holders interfere in public meetings and are not accountable to citizens hence the public apathy towards collective waste management decision making and their unwillingness to pay for waste services. The study concludes that for community participation in waste management to be effective, there should be online platforms for verification of the extent to which assemblies engage the public in collective decision making and this should be one criteria for allocating more common funds to district assemblies that perform well on this indicator.

Investigate the potential of using fuzzy similarity in decision making under uncertainty for mining projects

Multi criteria decision-making methods are used in mining engineering, in which various aspects are involved, such as selecting mining methods, mineral processing sites, etc. Decisions in this field can be made using a variety of techniques. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method is one of the most widely used decision-making methods based on multi criteria to make a decision. As part of this research, an attempt was made to investigate how fuzzy measurements can be applied to mining projects to improve the TOPSIS methods' efficiency. A full investigation of the mining method selection process, the waste dump site selection process at Gol-e-Ghar mine Area 3, the location of Bahabad Pelletizing plant, the appropriate site selection for crusher machine Sarcheshmeh copper mine, and loading-haulage equipment selection for Sungun copper mine has been carried out in order to achieve this goal. Accordingly, an area north of the pit was selected as the best location for the waste dump, open-pit mining was selected as the best mining method for the Gol-e-Gohar mine, Cite Number 2 was selected as the best location for the Bahabad Pelletizing Plant, the East side of the Sarcheshmeh copper mine is presented as the most suitable one, and shovel-truck-belt conveyor selected as the transportation method for Sungun copper mine. For mining projects, fuzzy similarity logic in the TOPSIS method provides both accurate and efficient results, as well as reducing the number of calculations. It also provides accurate results based on linguistic, numeric, and fuzzy values and determines whether all alternatives are feasible. Finally, it is shown that the TOPSIS based on fuzzy similarity for considering uncertainty in mining projects that are involved the decision-making process can be practical and useful.

Screening and Isolation of Polypropylene Degrading Fungi from Waste Dumping Site, Kolhapur, India

Polypropylene (PP) and other plastic wastes are found to accumulate in the environment, creating significant ecological issues. They are determined to be considered non-biodegradable, It has been established that once it enters the environment, it stays there permanently. The present investigation aims to biodegrade PP without physical treatment and exposing it to UV light and sunlight exposed to potential fungi isolated from the soil of solid waste dumping site based on 18SrRNA analysis and the isolated strains were identified as 98.54% similar to Cladosporium sp. The fungal strain was submitted with Gene Bank accession number ON024632 and registered as a Cladosporium halotolerans strain SUK PRAKASH. The degradation was performed for 8 months of incubation in the aqueous medium. The biodegradation of polypropylene FTIR spectroscopy was performed to further examine the sheets, and the results indicated that perhaps the bonds between the sheets were weakening and breaking. The biodegraded samples of without treated PP sheets, UV-exposed PP sheets, and sunlight-exposed PP sheets exhibit weight loss of 4.2%, 6.1%, and 8.6% respectively.

Community Perceptions on Health and Environmental Implications of Poor Management of Solid Waste Materials around local Dump Sites in the Buea Municipality, Cameroon

Numerous urban areas are today faced with many challenges posed by poor waste management and disposal especially in the developing countries. Analogously, these challenges are faced by urban dwellers in the Buea Municipality. The study aims at assessing the health and environmental implications of poor waste management in the Buea Municipality. It is an observatory and interrogatory study with a cross-sectional research design and dealing with 250 household dwellers selected through the simple random sampling technique. Primary data were obtained through questionnaires, interview guides, and field observations, supplemented with secondary data from magazines and published articles. Data collected were added codes and themes and inputted on Excel Version 17 and SPSS Version 13. Descriptive and inferential statistical techniques were adopted to establish percentiles, frequencies and magnitudes. Findings revealed that the siege population in the Buea municipality lacks adequate waste management facilities and this has pushed a significant proportion of them to always dump their waste materials generated from their booming domestic and economic activities into drainage channels, roadsides, and pits. The poor management of these waste materials has resulted to the occurrence of water and airborne diseases such as diarrhea, dysentery, cholera and typhoid fever affecting the population. Portable water sources and homes are also polluted by effluence from these waste dump sites. Urban dwellers adapt by boiling water from contaminated sources and cleaning up of nearby dirty gutters but their efforts are unfruitful. The work concludes that the Buea Municipality offers perennial and inter-generational opportunities to its population and recommends that holistic and bottom-top approaches such as daily clean-up campaigns; provision of trash-cans as well as the sensitization of the general community must be implemented in order to provide a congenial environment for the population.

Determination of bio-accumulated Cd, Cr, Cu, Ni and Pb in a wild plant Lantana camara L. Verbenaceae, grown on waste dump site and assessment of its phyto-extraction potential for studied metals

The inputs of chemical fertilizers, street runoffs and regular use of heavy metal contaminated water to irrigate farm crops may result in elevated levels of heavy metals in agri-soil. The food crops growing on such soils may selectively bio-accumulate these metals, which usually depend on the concerned plant’s bio- accumulation potential for concerned metal and characteristics of the soil. This study was aimed to evaluate the bio-accumulation of Cd, Cr, Cu, Ni and Pb in the root, stem and leaves of the wild plant Lantana camara L., Verbenaceae, grown on waste dump site, by analyzing levels of studied metals in soil and plant parts. The bio-concentration factors (BCFs) and translocation factors (TFs) for metals under study were also evaluated, to find out the suitability of Lantana plant for phytoextration of the tested metals. The observed order of metal concentrations in soil samples was Pb (8.91± 0.54) &gt; Cr (6.42 ±0.43) &gt;Cu (1.91± 0.17) &gt; Ni (1.42± 0.13) &gt; Cd (0.86± 0.09, mg/Kg). The observed levels of studied metals in roots, stem and leaves of Lantana were, Pb(8.73±0.32)&gt; Cr (2.96± 0.18)&gt; Cu (2.16±0.15)&gt; Ni (1.38±0.12)&gt;Cd (0.54±0.03mg/kg); Pb(5.18±0.24)&gt;Cr (3.18±0.18)&gt;Cu (2.42±0.17) &gt;Ni (1.49±0.12) &gt;Cd (0.28±0.02, mg/Kg) and Pb (6.07±0.27)&gt; Cr (1.30±0.13) &gt;Cu (0.88±0.07) Ni (0.16±0.02) &gt;Cd (0.10 ±0.01, mg/Kg), respectively. The bio-concentration factors for Lantana from soil to roots (BCFRoot) and from roots to shoots (BCFShoot) for Cd, Cr, Cu, Ni and Pb were 0.63, 0.46, 1.13, 0.97 (~ 1.00) and 0.98 (~ 1.00) and 0.70, 1.51, 1.49, 1.20 and 1.29, respectively. The translocation factors from root to stem (TFStem) and from stem to leaves (TFLeaf) for tested metals in Lantana camara were, 0.52, 1.07, 1.12, 1.08, 0.59 and 0.36, 0.41, 0.36, 0.11, 1.17, respectively. Thus, the recorded BCF values, mostly being &gt;1, makes Lantana suitable for phyto-extraction of tested metals from agri-soil and medium to good translocation factors (TF) suggested the potential of the plant to translocate the tested metals into the stem and leaves.

Pre-treatment, Physicochemical Properties and Production of Bioethanol from Rice Husk using Fungi Isolated from Waste Dumpsite in Kaduna, Nigeria

This research is based on the pre-treatment and physicochemical characterization of rice husk and production of Bioethanol from rice husk using fungal isolates obtained from waste dump sites in Kaduna Nigeria. Standard procedures were followed. The results revealed a reduction in lignin (from 21.40 to 12.08%), hemicellulose (22.04-18.92%), protein (14.56-8.56%) and ash (1.31-1.04%) contents which resulted to an increase in the cellulosic fraction (49.55-58.29%) of the rice husk.. A significant difference (p&lt;0.05) was observed in the reducing sugar concentrations of the 50g substrate concentration using Aspergillus niger SIF2 (0.60±0.30mg/ml), Aspergillus flavus CMXY22565 (0.56±0.29mg/ml) and a consortium (1.17±0.82mg/ml) of both organisms after 120 hours of enzymatic hydrolysis. The results also revealed a significant yield (p&lt;0.05) in bioethanol production using Pichia kudriavzevii IPBCC.y.161552 (4.91±2.51%), Saccharomyces cerevisiae FJI (5.39±2.87%) and a consortium (9.02±4.83%) of both organisms. There was an increase in temperature and titratable acidity and a decrease in pH and specific gravity. The FTIR revealed a high ethanol content of 68% from the bioethanol produced from the 50g substrate concentration hydrolysed and fermented using a consortium of molds and yeasts. The results therefore suggest that bioethanol can be produced from rice husk with maximum yields obtained using a consortium of Aspergillus niger SIF2 and Aspergillus flavus CMXY22565 for hydrolysis as well as a consortium of Saccharomyces cerevisiae FJI and Pichia kudriavzevii IPBCC.y.161552 for fermentation.

A bioanalytical approach for assessing the effects of soil extracts from solid waste dumpsite in Calabar (Nigeria) on lipid and estrogenic signaling of fish Poeciliopsis lucida hepatocellular carcinoma-1 cells in vitro and in vivo African catfish (Clarias gariepinus)

ABSTRACT In applying bioanalytical approaches, the aim of this study was to determine the toxicity of contaminants derived from a solid waste dumpsite in Calabar (Nigeria), by investigating the alterations of lipid and estrogen signaling pathways in Poeciliopsis lucida hepatocellular carcinoma-1 (PLHC-1) cells and compared to in vivo African catfish (Clarias gariepinus), using polar, nonpolar and elutriate extraction methods. Cells were exposed for 48 hr period to different concentrations of the contaminant extracts. The PLHC-1 cells were evaluated for lipid responses as follows adipoRed assay, retinoid x receptor (rxr), peroxisome proliferator-activated receptor isoforms (ppar-α and γ), estrogen receptor (er-α) and vitellogenin (vtg) transcripts. The lipid signaling activation was also assessed in vivo using C. gariepinus, where hepatic levels of ppar-α were determined at both transcript and functional proteins levels. Data showed variable-, extract type and concentration-specific elevations in mRNA and protein levels for lipidomic and estrogenic effects. These effects were either biphasic at low and high concentrations, depending upon extract type, or concentration-dependent elevations. In general, these toxicological responses may be attributed to soil organic and inorganic contaminants burden previously derived from the dumpsite. Thus, our data demonstrate a unique lipid and endocrine-disruptive chemical (EDC) effects of each soil extract, suggesting multiple and complex contaminant interactions in the environment and biota. Analysis of numerous soil- or sediment-bound contaminants have numerous limitations and cost implications for developing countries. Our approach provides a bioanalytical protocol and endpoints for measuring the metabolic and EDC effects of complex environmental matrices for ecotoxicological assessment and monitoring.

Effect of Solid Waste Disposal on Chemical Quality of Groundwater in Ife North Local Government Area, Osun State, Nigeria: A GIS-Based Assessment

Indiscriminate waste disposal is a major environmental challenge in developing countries, especially as thewastes often end up downstream. The present study investigated the vulnerability of selected groundwatersources in semi-rural communities in Ife North Local Government Area of Osun State, Nigeria, tocontamination by adjacent waste dumpsites. The specific objective was to assess the chemical quality of thegroundwater in the area. Data used were results of the laboratory investigation of selected water samplesfrom sampled groundwater sources and information about the uses of the groundwater by the residents. Theparameters pH, conductivity, and TDS were assessed in situ and chemical parameters such as Lead, Iron,Copper and Sulphate were assessed in the laboratory. Results showed that the groundwater sources close tothe dumpsites were more contaminated than the sources farther from the dumpsites. At distances less than50m to the dumpsites, the concentration of the chemical metals did not meet the WHO standard, however, itdecreased with distance from the dumpsite. For instance, although sulphate concentration was below therecommended maximum, sulphate concentration decreased with distance from the dumpsite. The studyconcluded that groundwater sources around dumpsites were contaminated and unfit for potable use in thearea.

Losing Ground: Targeting Agricultural Land Take by Enabling a Circular Economy in Construction

Among the numerous causes of soil degradation, one of the most severe and difficult to reverse is land take. Land take results in the loss of valuable ecosystem services that negatively impact soil health, especially in agricultural areas. The main drivers of land take are increased provision of housing, schools, hospitals, industrial and commercial sites, transport networks and infrastructures, mines, quarries and waste dumpsites. Globally, the rate and scale of land take is increasing. Given the impact on soil ecosystem services such as the carbon, hydrological and nitrogen cycles, preventing agricultural land take is essential if the triple planetary ecological crises of climate change, biodiversity loss and pollution are to be addressed. Most countries use sustainable management techniques to limit land take by development projects. In this opinion paper, we argue that the circular economy concept could help to establish an alternative perspective on how to understand and address the agricultural land take problem. Law and policy need to foster a systemic transition to a circular economy throughout the entire construction sector’s multiple material life cycles if it is to significantly reduce land take. We use England as a case study to show how the UK government can revise and build on current policy to enable a transition to a more circular construction sector. The case study provides valuable lessons for other countries at a crossroad on land use policy on how fostering a circular construction economy can reduce land take and maintain agricultural soil’s ecological services.

Comprehensive assessment of heavy metal contaminations in agricultural soil through Pollution Indices from a rapidly developing city of India

This study has been conducted for the comprehensive evaluation of heavy metals (HMs) contamination such as Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb in agricultural soils via pollution indices i.e. geoaccumulation index (Igeo), contamination degree (CD), pollution load index (PLI), potential ecological risk (PRI) etc. Assessment for the determination of ecological damage was caused by these HMs in different agro-ecosystems around metropolitan city Lucknow. For this, data has been taken from our previous study8 depicting significant enrichment of above mentioned HMs in agricultural soil present near riparian areas, brick kilns, waste dump sites etc. Our results indicated that soil samples collected from Gaughat (GAF) and Sitapur (SAF) showed very high degree of contamination (CD&gt;24). Further, pollution load index also reflected “very high” and “moderate to high” contamination with values 6.9075 and 3.3214 in these two sites respectively. Overall, Igeo values indicated moderate contamination with Mn and Ni metals and low contamination with Cr, Cu, Zn and Cd metals. However, Igeo with value 4.923 indicated extremely high degree of contamination due to Cd in Gaughat (GAF) soil. In the view of potential ecological risk index, GAF site poses a “very high” potential ecological risk while maximum sites pose “moderate” ecological risk. The ecological risk factor in agricultural soil was in the following descending order: Cd &gt; Ni &gt; Cu &gt; Pb &gt; Cr &gt; Mn &gt; Zn &gt; Fe. Cadmium predominantly contributes significant amount to the PRI of soil while Ni, Cu, Pb, Cr, Mn and Zn showed low ecological risk.

Composition and characteristics of excavated materials from a legacy waste dumpsite: Potential of landfill biomining

Landfill biomining (LFBM) has been proposed as a viable method for the reclamation of legacy waste dumpsites as well as the subsequent recovery of valuable resources and land value spaces. Despite these advantages, the potential of LFBM faces a significant challenge due to the composition, characteristics and end-use of the excavated materials. This paper assesses the composition of the excavated waste obtained during the LFBM operation of the four legacy waste heaps at the Boragaon dumpsite in North-East India and determines the physicochemical characteristics crucial for the material and energy recovery from the key reclaimed fractions. The compositional analysis revealed that the proportion of combustible and non-combustible fractions decreases from the youngest heap HP4 to the oldest heap HP1 due to variations in the consumption habits of the local community and the inadequate recycling of recyclable materials. However, the proportion of fine fraction (FF) shows an increasing trend from HP4 to HP1, suggesting enhanced biodegradation of easily degradable waste over the years. The proximate and energy content analysis suggest that refuse-derived fuel (RDF) preparation is the most suitable valorization option for the combustible fractions since surface defilements are too high for good quality material recovery. The elevated amount of organic matter and leachable heavy metals indicate that unrestricted reuse of FF as earth-fill material can cause long-term settlements and groundwater contamination, respectively. Even though every dumpsite is different in characteristics, the findings of this case study can assist in developing new strategies for recycling excavated waste.

AMYLOLYTIC POTENTIAL OF Arthrobacter sp. AND Bacillus aerius FROM WASTE DUMP-SITES OF TWO BAKERIES LOCATED WITHIN KADUNA METROPOLIS, NIGERIA

Bakery waste dumpsites are believed to harbour a variety of bacteria due to the presence of organic materials like flour, sugar, and other food residues. The conditions in these environments support the growth of bacteria with the ability to degrade starch into simple sugars because they produce amylases, an enzyme pivotal to the food and beverage production. As Amylases progressively gain relevance in several other starch-based processes, their availability becomes insufficient, and the need for amylases with unique and superior efficiency increases. The focus of this study was to isolate and characterize bacteria with amylase activity from the soil of bakery waste dumpsites to provide valuable insight into cheap sources of amylolytic bacteria and their potential biotechnological applications. The starch-agar medium was used to isolate and screen amylase-producing bacteria by streak plate method. Two isolates, A2 and A4, showing the most hydrolytic activities of 21 + 0.1 mm and 25 + 0.1 mm, respectively, were identified by their cultural and cellular morphologies, biochemical characteristics, 16S rRNA gene sequence, and nearest phylogenetic neighbour as Arthrobacter sp. and Bacillus aerius. Based on their culture and amylolytic temperatures, Arthrobacter sp. (37 0C) and Bacillus aerius (45 0C) tend to produce amylases that can be explored in low to moderate and moderate to torrid industrial processes, respectively.

Isolation and Screening of Microorganisms from Waste Dumping Sites for Biosorption of Cadmium and Lead

Heavy metal poisoning of the environment poses a serious threat to ecosystems and human health. Landfills have been found to harbor diverse microbial communities capable of bioremediating such contaminants via biosorption. Unlike traditional methods of heavy metal remediation, which often involve costly and resource-intensive techniques, biosorption offers a promising alternative that harnesses the natural capabilities of microorganisms. The objective of this research was to identify and screen microorganisms from landfills for their ability to bio-sorb cadmium (Cd) and lead (Pb). The present study deals with the isolation and screening of the microorganisms capable of removing heavy metals from the area near Dehradun Municipal Solid Waste Management Pvt. Ltd. Among the 17 bacterial isolates and 2 fungal isolates, only 7 bacteria and one fungal strain were able to absorb the heavy metal concentration. Among the 7 bacterial strains, the percentage of microbes with the ability to absorb Pb ranged from 35% to 70%, while the percentage of microbes with the ability to absorb Cd ranged from 20% to 50%. On the other hand, the fungal strain had an absorption capacity of about 80% for both Pb and Cd. This study emphasizes the potential of microorganisms isolated from landfills as attractive candidates for Cd and Pb biosorption. These isolates show significant tolerance and efficient biosorption capacities, making them good candidates for further exploration and prospective application in the bioremediation of heavy metal-contaminated environments.

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.

Human health risks of metal contamination in Shallow Wells around waste dumpsites in Abeokuta Metropolis, Southwestern, Nigeria.

Metal contamination in shallow wells through solid waste leaching is a serious environmental problem with contribution to global cancer cases. This paper evaluated the health risks of metals in shallow wells around dumpsites in the Abeokuta metropolis, Nigeria. Five dumpsites were purposively selected to sample twenty-five shallow wells. In situ and laboratory analyses for physico-chemical parameters, copper, lead, cadmium, iron, and chromium were conducted following the APHA standard procedure. Carcinogenic and non-carcinogenic risks for oral and dermal routes were evaluated for adult males and females, children, and infants. Findings revealed that all wells were acidic (pH = 5.82-6.48), with Fe and Cd concentrations above the established limits. The wells around Obada, Obantoko, and Saje dumpsites had high EC (up to 1200 µS/cm), Cu, and Pb concentrations above the permissible limits. Non-carcinogenic risks for oral ingestion were significant for all age groups (hazard index: HI > 1), and the significance level across dumping areas increased in the order: Saje > Obantoko > Obada > Idi-aba > Lafenwa. All wells assessed in Saje and Obantoko recorded significant HI of dermal exposure for children and infants. Cancer risks were significant for all age groups (CR > 1.0E - 04), and metal contributions followed: Cd > Cr > Pb. The overall trend of significant risks for non-carcinogenic and carcinogenic via oral and dermal routes is in the order of infant > children > adult female > adult male. This suggests that groundwater users within the studied areas may experience diverse illnesses or cancer in their lifetime, particularly children and infants.