Waste Contamination Research Articles

Effect of leachate contamination in municipal solid waste on clay liner characteristics

Landfill leachate is generated as a consequence of water percolation through the solid waste, oxidation of the waste, and corrosion of the waste. Under-designed landfill sites allow the leachate to easily pass through the soil strata. To identify the effect of contaminants on the engineering properties of the clay liner, a pilot-scale lysimeter was developed. Experiments on two types of soils polluted with leachate were conducted which included silty clay and soil enhanced by chemical stabilization. Lime and silica fume are used as reactive barriers in landfill earthen liners. The leachate generated was monitored periodically and sampled for (pH, Electrical conductivity, Chemical oxygen demand, Chloride, Total dissolved solids, and total suspended solids). Lime (L), silica fume (SF), and lime-silica fume (L-SF) mix have been used for stabilizing soil. Three percentages were used for lime (2%, 4% and 6%) and three percentages were used for silica fume (3%, 5% and 7%) and the optimum percentage of silica fume (5%) was mixed with the proportions of lime. The optimum lime values are 4% from the research and 5% for silica fume. Soil samples were analyzed over a maturation period of 135 days for each run to identify the chemicals and their effect on the soil characteristics. The plasticity index of the stabilized soil continues to decline until it reaches 36% over the 135 days of the maturing period. Furthermore, an increase in silty clay soil hydraulic conductivity was observed from 3.3 × 10−6 cm/sec to 5 × 10−6 cm/sec at 135 days of maturation. Whereas there is a sharp decrease in hydraulic conductivity to achieve a maximum value in the stabilized soil (1.25 ×10−10 cm/sec). Based on laboratory test results, it can be concluded that soil stabilization can improve the geotechnical properties of landfill earthen liners due to pozzolanic reactions.

Counting and measuring the size and stomach fullness levels for an intelligent shrimp farming system

The penaeid shrimp farming industry is experiencing rapid growth. To reduce costs and labour, automation techniques such as counting and size estimation are increasingly being adopted. Feeding based on the degree of stomach fullness can significantly reduce food waste and water contamination. Therefore, we propose an intelligent shrimp farming system that includes shrimp detection, measurement of approximated shrimp length, shrimp quantity, and two methods for determining the degree of digestive tract fullness. We introduce AR-YOLOv5 (Angular Rotation YOLOv5) in the system to enhance both shrimp growth and the environmental sustainability of shrimp farming. Our experiments were conducted in a real shrimp farming environment. The length and quantity are estimated based on the bounding box, and the level of stomach fullness is approximated using the ratio of the shrimp´s digestive tract to its body size. In terms of detection performance, our proposed method achieves a precision rate of 97.70%, a recall rate of 91.42%, a mean average precision of 94.46%, and an F1-score of 95.42% using AR-YOLOv5. Furthermore, our stomach fullness determined method achieves an accuracy of 88.8%, a precision rate of 91.7%, a recall rate of 90.9%, and an F1-score of 91.3% in real shrimp farming environments.

A Comparative Assessment of High-Throughput Quantitative Polymerase Chain Reaction versus Shotgun Metagenomic Sequencing in Sediment Resistome Profiling

Prolonged and excessive use of antibiotics has resulted in the development of antimicrobial resistance (AMR), which is considered an emerging global challenge that warrants a deeper understanding of the antibiotic-resistant gene elements (ARGEs/resistomes) involved in its rapid dissemination. Currently, advanced molecular methods such as high-throughput quantitative polymerase chain reaction (HT-qPCR) and shotgun metagenomic sequencing (SMS) are commonly applied for the surveillance and monitoring of AMR in the environment. Although both methods are considered complementary to each other, there are some appreciable differences that we wish to highlight in this communication. We compared both these approaches to map the ARGEs in the coastal sediments of Kuwait. The study area represents an excellent model as it receives recurrent emergency waste and other anthropogenic contaminants. The HT-qPCR identified about 100 ARGs, 5 integrons, and 18 MGEs (total—122). These ARGs coded for resistance against the drug classes of beta-lactams > aminoglycoside > tetracycline, macrolide lincosamide streptogramin B (MLSB) > phenicol > trimethoprim, quinolone, and sulfonamide. The SMS picked a greater number of ARGs (402), plasmid sequences (1567), and integrons (168). Based on the evidence, we feel the SMS is a better method to undertake ARG assessment to fulfil the WHO mandate of “One Health Approach.” This manuscript is a useful resource for environmental scientists involved in AMR monitoring.

Coffee Silverskin Phytocompounds as a Novel Anti-Aging Functional Food: A Pharmacoinformatic Approach Combined with In Vitro Study.

Coffee became a beverage that was in demand in the world and consequently produced millions of tons of coffee byproducts namely coffee silverskin (CS). Unutilized CS will be waste and cause environmental pollution such as greenhouse gas emissions, landfill waste, and groundwater contamination. This is a research concern at this time, although many studies have been conducted to find newer applications of CS, exploration of its benefits in the health sector is still limited. Therefore, exploring the benefits of CS to prevent or delay aging will be very interesting to develop in functional food industry technology. Therefore, this study aims to report profiling metabolites or phytochemicals, biological activities in terms of antioxidant activity, and potential anti-aging of CS via molecular docking simulation and in vitro modulation of the mTOR/AMPK/SIRT1 pathway. Something new has been obtained from this work, the profile of phytocompounds, and biological activities both in molecular docking simulation and in vitro studies. Some of the compounds observed in Robusta CS extract (rCSE) such as Epicatechin, Kaempferol, and Quercitrin, and Arabica CS extract (aCSE) such as (+)-Catechin dan Naringin have promising potential as inhibitors of iNOS, mTOR, and HIF-1α via molecular docking simulation. Interestingly, the in vitro biological activity assay of antioxidant and anti-aging activity, rCSE showed the same promising potential as the results of a molecular docking simulation. More interestingly, AMPK/SIRT1/mTOR expressions are well modulated by rCSE compared to aCSE significantly (p < 0.05). This makes the rCSE have promising biological activity as a candidate for functional food development and/or treatment agent in combating free radicals that cause the aging process. In vivo studies and human trials are certainly needed to see the further efficacy of the rCSE in the future.

Food waste initiatives in the tertiary sector in Aotearoa New Zealand

Food waste is a global issue; 30 to 40% of all food is wasted. Despite a growing body of research, information on food waste in the tertiary education sector is lacking. The variety and size of foodservice operations at tertiary institutes provides an opportunity to address food waste and work towards Sustainable Development Goal Target 12.3. We investigated food waste initiatives at 13 tertiary institutes in Aotearoa and identified challenges to further initiative implementation. Semi-structured interviews were conducted with staff working in sustainability at each institute. The most common initiatives included worm farms (n=11), solutions for leftover foods (n=11), and composting (n=9). Challenges to the initiatives included: the Covid-19 pandemic; contamination of organic food waste destined for composting; attitudes of individuals and institutes; and funding and resources. Although a range of initiatives are in place, these approaches are near the bottom of the waste hierarchy. New initiatives should be developed to reduce the volume of excess food, focusing on prevention and avoidance rather than recycling and recovery. Tertiary institutes in Aotearoa should also adopt the “Target, Measure, Act” approach to tackle food waste, through setting formal goals, regularly measuring food waste, and acting by implementing a wide variety of initiatives.

TiO2 loaded on glycidol functionalized poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) nanobiocomposite film for photocatalytic and antibacterial activities

The rapid acceleration of industrialization and urbanization has exacerbated water pollution, which is primarily caused by the presence of highly toxic, non-biodegradable contaminants in industrial waste and effluents. In response to this urgent issue, a novel nanobiocomposite film with titanium dioxide (TiO2) loaded onto a poly(3-hydroxybutyrate-co-18 mol% 3-hydroxyhexanoate) (18PHBH) matrix was developed to serve as an effective dual-function material with photocatalytic and antibacterial properties. Through Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR), Diffuse reflectance ultraviolet-visible (DRUV-Vis), Scanning Electron Microscope (SEM), and X-ray diffraction (XRD) analyses, the physicochemical properties of the TiO2/Gly/18PHBH nanobiocomposite film were exhaustively characterized, revealing effective TiO2 loading and uniform distribution on the film's surface. The film exhibited extraordinary photocatalytic degradation of methylene blue (MB) dye, with the 5TiO2/Gly/18PHBH film demonstrating the greatest efficiency. In addition, antibacterial testing revealed that the film was effective against 99.8 % of Staphylococcus aureus and 96.9 % of Pseudomonas aeruginosa. These results demonstrate the potential of polyhydroxyalkanoate-based films as exceptional nanoparticle matrices and position the 5TiO2/Gly/18PHBH film as a versatile candidate for applications in photocatalysis and antibacterial interventions, providing innovative solutions to critical environmental challenges.

Seagrass sponge (Agelas conifera: Demospongia) potential of microplastic accumulation from Pramuka Island, Seribu Islands

Sponges is a benthic filter feeder, that potentially absorb and accumulate substances from the aquatic environment. Pramuka Island is a small island with tourism area, that could contribute contamination of domestic and anthropogenic waste in its waters, including microplastics. This study aimed to examine the potential for microplastic accumulation in the body tissues of the seagrass-sponge Agelas conifera in Pramuka Island, DKI Jakarta. Sponge samples were collected from two stations around the final disposal site and household liquid waste disposal. Microplastic observations were carried out by adding KOH solution to remove sponge organic matter and saturated NaCl to separate the density. Microplastic observations were carried out using a stereo microscope. The result showed that sponge tissue could accumulate 166.66-300 particles/g of microplastic at both sampling stations, with the highest abundance of fibre types at station 1. The abundance of microplastic in sediment samples is 0.76-0.97 particles/g, with fragment type was found dominantly, whilst microplastic found in the water samples is 1,550 -1,956.66 particles/m3, mostly by fibre type (1230 particles/m3 ). The abundance and types of microplastic found in sediment, water and sponges samples showed a significant difference between samples with a significant value of 0.01 (ANOVA, p values).

Managing Microplastics in the Kingston, Ontario, Community: A Novel One Health Innovation

The adverse impacts of microplastics on human health, non-human animals, and the environment are long-standing issues that affect communities across Canada and worldwide. The slow degradation of plastics and their bioaccumulation in plants, animals, and ecosystems can lead to poor growth outcomes and physiological side effects. Comprehensive initiatives that address the "Reduce, Reuse, Recycle" principles for plastic are urgently needed. To support Kingston City Council's mission to reduce plastic and waste contamination in waterways, this proposed initiative aims to redirect plastic bags from entering the environment and repurpose them into sleeping bags.

Comparison of antibiotic-resistant Escherichia coli and extra-intestinal pathogenic E. coli from main river basins under different levels of the sewer system development

Antimicrobial-resistant Escherichia coli in the aquatic environments is considered a strong indicator of sewage or animal waste contamination and antibiotic pollution. Sewer construction and wastewater treatment plant (WWTP) infrastructure may serve as concentrated point sources of contamination of antibiotic-resistant bacteria and antibiotic resistance genes. In this study, we focused on the distribution of antimicrobial-resistant E. coli in two rivers with large drainage areas and different urbanisation levels. E. coli from Kaoping River with drainage mainly from livestock farming had higher resistance to antibiotics (e.g. penicillins, tetracyclines, phenicols, aminoglycosides, and sulpha drugs) and presented more positive detection of antibiotic-resistance genes (e.g. ampC, blaTEM, tetA, and cmlA1) than that from Tamsui River. In Kaoping River with a lower percentage of sewer construction nearby (0–30%) in contrast to a higher percentage of sewer construction (55–92%) in Tamsui River, antimicrobial-resistant E. coli distribution was related to livestock farming waste. In Tamsui River, antimicrobial resistant E. coli isolates were found more frequently in the downstream drainage area of WWTPs with secondary water treatment than that of WWTPs with tertiary water treatment. The Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR showed that the fingerprinting group was significantly related to the sampling site (p < 0.01) and sampling date (p < 0.05). By utilising ERIC-PCR in conjunction with antibiotic susceptibility and antibiotic-resistance gene detection, the relationship among different strains of E. coli could be elucidated. Furthermore, we identified the presence of six extra-intestinal pathogenic E. coli isolates and antibiotic-resistant E. coli isolates near drinking water sources, posing a potential risk to public health through community transmission. In conclusion, this study identified environmental factors related to antibiotic-resistant bacteria and antibiotic-resistance gene contamination in rivers during urban development. The results facilitate the understanding of specific management of different waste streams across different urban areas. Periodic surveillance of the effects of WWTPs and livestock waste containing antibiotic-resistant bacteria and antibiotic-resistance genes on river contamination is necessary.

Eco-friendly and humidity-sensitive cellulosic triboelectric materials tailored by xylanase for monitoring the freshness of fruits

Detecting the freshness of fruits during the storage period plays crucial role in reducing food waste and food-borne contamination. In this study, for the first time, a novel humidity-sensitive tribopositive cellulosic material was successfully tailored by biological xylanase under mild conditions for monitoring the freshness of fruits within packing microenvironments. Benefiting from the more exposed -OH groups within created microstructures and the residual hydrophilic enzyme protein on the surface of fibers, the output voltage signal of the TENG decreased with gradual increasing the relative humidity (RH) from 25%RH to 95%RH. Moreover, the optimized TENG-72 h presents a higher humidity-sensitivity of V25% RH/V95% RH = 11.3 toward wide range humidity, which was about 3.65 times higher than pristine cellulose-based TENG. The constructed enzymatic cellulose TENG displayed discernible output signal response to the humidity within packaging microenvironments, which was highly correlated with the physiological parameters of fruits, further reveling the great potential application in monitoring the freshness of fruits. Overall, this research not only proposed a green and mild strategy for tailoring the humidity-sensitivity of cellulosic fibers, but also promotes the development of biodegradable triboelectric materials in the field of food safety.

Computational Examination of Heat and Mass Transfer Induced by Ternary Nanofluid Flow across Convergent/Divergent Channels with Pollutant Concentration

Studying waste discharge concentration across a convergent/divergent channel is essential in environmental-related applications. Successful environmental administration must understand the behavior and concentration of waste contaminants released into these channels. Analyzing waste discharge concentrations aids in determining the efficacy of treatment techniques and regulatory controls in lowering pollutant scales. Because of this, the current analysis examines the ternary-based nanofluid flow across convergent/divergent channels, including non-uniform heat source/sink and concentration pollutants. The study also concentrates on understanding the movement and heat transmission characteristics in ternary-based nano-liquid systems with divergent and convergent channels and maximizing the ternary nanofluid flow’s effectiveness. The equations representing the flow, temperature, and concentrations are transformed into a system of ODEs (ordinary differential equations) and are obtained by proper similarity variables. Further, solutions of ODEs are gathered by using the Runge Kutta Fehlberg 4-5 (RKF-45) method and shooting procedure. The significant dimensionless constraints and their impacts are discussed using plots. The results mainly focus on improving local and external pollutant source variation will enhance the concentration for the divergent channel while declining for the convergent channel. Adding a solid fraction of nanoparticles will escalate the surface drag force. These findings may enhance heat management, lessen pollutant dispersion, and enhance the circulation of nanofluid systems.

Nanomaterials as endorsed environmental remediation tools for the next generation: Eco-safety and sustainability

The increased peril of various environmental pollutants causing enormous damage to the environment and human beings has raised red flags worldwide. Despite the numerous attempts that are daily made to reduce the amounts of hazardous substances, still there is a need for urgent action toward finding successful solutions for pollutant removal. Therefore, we are witnessing that environmental safety is nowadays a prime global concern and challenge. In that light, nano-remediation is attracting increasing attention as a cutting-edge technology that has the potential to revolutionize the way of managing and remediating hazardous waste and environmental contamination with the potential of addressing environmental problems. However, despite numerous reports on the application of nanomaterials in environmental remediation, there are still many gaps in deciphering the mode of action, eco-safety, and sustainability of various nanomaterials for long-term application. Therefore, this review summarizes the current status of bio-based nanoparticles, and their synthesis over the last decade, from classical to modern innovative ways, where more research attention has been drawn toward environmentally friendly materials and the most recent trends in green direction for their fabrication. Further, it provides a comprehensive discussion to present insights into the state of the art of green-synthesized nanoparticles and emphasizes the key issues in their advantages over the traditional methods and potential obstacles and constraints for their implementation in cleaning up contaminated sites. Lastly, this review points to key steps that should advance current trends and enable further development in boosting the power of nanotechnology for a long-term and sustainable application in environmental remediation.

Waste management using the takakura method at the Tingkir Islamic Boarding School, Salatiga

Central Java province produces the most waste in Indonesia, reaching more than 5 million tons per year. Waste is a complex problem and has a negative impact on environmental sustainability, especially food waste and plastic waste. The purpose of this community service is to reduce the waste volume in temporary shelters, prevent contamination of waste into the environment and build awareness and concern for the environment among Islamic boarding school students. The methods used in community service activities are lectures, demonstrations of making compost using the Takakura method and group discussions attended by 35 students. The results of the program showed an increase in students' knowledge about processing waste into compost (65.8%). The organic compost produced can be used for plant media, fertilizer, business opportunities and additional income for students so that it can be a motivation to produce organic compost from waste management.

Isolation and screening of keratinolytic bacteria from feather dumping soil near in Lucknow and Kanpur city, North region of Indian

Background Keratinases are proteolytic enzymes that have the capability of degrading insoluble keratin substrates. LS4, LS5, and KS3 were newly isolated strains showing ability to hydrolyze keratins and keratin based products. Objective In this study, different bacterial strains were isolated from soil, screened for protease and keratinase production, and the best isolates were identified. Methods Serial dilution and plating method were used for isolation of pure bacterial culture. Isolated, 48 strains were screened, and their feather degrading ability on feather meal agar plates and keratin azure-based agar. The proteolytic activity of the isolates was also screened on casein agar. Results Three strains; LS4, LS5, and KS3 shows keratinolytic activity that reveal the keratinase enzyme on medium; feather meal agar, keratin azure agar, and casein agar. Among all the three strains (LS4, LS5, and KS3), KS3 show largest inhibition zone that show maximum enzymatic activity. For its characterization 16S RNA was performed, sequence KS3 was submitted to GenBank and was identified as Bacillus tropicus KS3. Newly isolated strain B. tropicus KS3 showed the keratinase production and highest keratinase activity (35.06 ± 2.5 U/ml). B. tropicus KS3 also show the highest degradation of feather efficiently showed 84% of whole chicken feather biodegradation at 37 °C within 15 days among all the isolated strains. Conclusion Keratinase enzyme possesses a wide range of potential applications in the bioremediation of feather waste and bio-fertilizer in agricultural land. The industry demands a better source of this enzyme due to its multivariate application and huge market demand. In the present study, a novel keratinase-producing bacteria was isolated and characterized as Bacillus tropicus KS3 from poultry waste contamination soil.

Microbial Mercury Reduction Potential In Gold Mining Waste: Bacillus Subtilis And Pseudomonas Aeruginosa Study

This study aims to investigate the potential of Bacillus subtilis and Pseudomonas aeruginosa in removing mercury from wastewater generated by Artisanal and Small-scale Gold Mining (ASGM) in Tatelu and Talawaan Villages, North Minahasa, Indonesia. Following the ban on mercury use in gold processing, there is a need for effective mercury-free processing technologies to mitigate environmental and health impacts. The research begins with the cultivation of rejuvenated bacteria, followed by a preliminary test to establish bacterial growth curves. This test provides guidelines for the duration of stirring during subsequent biodegradation processes. The biodegradation test involves mercury content analysis of wastewater samples, followed by Minimum Inhibitory Concentration (MIC) testing using lactose broth as the bacterial growth medium. The MIC test helps determine the variations in mercury concentrations and the efficacy of the selected bacteria in degradation. The objectives of this study are to assess the capability of Bacillus subtilis and Pseudomonas aeruginosa in removing mercury from ASGM wastewater. The findings hold significant potential for the development of efficient and economically viable biotreatment technologies for addressing mercury contamination in hazardous waste produced by small-scale gold mining. The innovative technology proposed in this study can be readily adopted by other gold mining industries to ensure compliance with stringent environmental and health standards.

Impact of polystyrene microplastics on cadmium uptake in corn (Zea mays L.) in a cadmium‐contaminated calcareous soil

AbstractMicroplastics (MPs) are small plastic fragments that have spread globally, but the interaction between MPs and heavy metal soil contamination on plant growth has received little attention. In this study, the impact of polystyrene (PS) on maize growth in cadmium (Cd) polluted soil was examined through a randomized complete block design (RCBD) experiment. The results revealed that increasing PS levels in soil led to an increase in Cd concentration in maize shoots and roots compared to the control. Furthermore, the growth inhibiting impact of PS was enhanced by the presence of Cd. PS reduced the dry weights of the shoots and roots, resulting in lower overall dry weights. This study also demonstrated a distinct alteration in the soil pH following the addition of PS, with pH values increasing. PS enhanced the disruption of Cd and decreased the chlorophyll index, plant height, and leaf area by increasing the Cd concentration in the maize plant. These findings highlight the negative impact of PS on plant growth and the exacerbation of Cd contamination in soil. Proper disposal of plastic waste is crucial to mitigate its detrimental effects on the environment. Further research is needed to examine the impact of MPs on soil contamination and their interactions with plants. Understanding the mechanisms of the interactions between MPs and heavy metals will aid in developing strategies to reduce the risks associated with plastic waste and soil contamination. These findings underscore the need for effective waste management practices to prevent further contamination of the environment.

Quantifying Plastic Waste and Microplastic Contamination in African Aquatic Systems: An Imperative for Sustainable Waste Management

Quantifying Plastic Waste and Microplastic Contamination in African Aquatic Systems: An Imperative for Sustainable Waste Management

Free nitrous acid-assisted asymmetrical alternating current electrochemistry (FNA-AACE) for multi-heavy metals decontamination in waste activated sludge

Heavy metal contamination of waste activated sludge (WAS) is a key factor limiting the land application of sludge for nutrients recovery. This study proposes a novel free nitrous acid (FNA)-assisted asymmetrical alternating current electrochemistry (FNA-AACE) process to achieve high-efficiency decontamination of multi-heavy metals (Cd, Pb, and Fe) in WAS. The optimal operating conditions, the heavy metal removal performance of FNA-AACE, and the related mechanisms for maintaining the high performance were systematically investigated. During the FNA-AACE process, FNA treatment was optimal with an exposure time of 13 h at a pH of 2.9 and an FNA concentration of 0.6 mg/g TSS. Then the sludge was washed with EDTA in a recirculating leaching system under asymmetrical alternating current electrochemistry (AACE). The 6-h working and the following electrode cleaning were defined as a working circle of AACE. After three cycles of working-cleaning periods in AACE treatment, the cumulative removal efficiency of the toxic metals Cd and Pb reached over 97% and 93%, respectively, whilst that of Fe was greater than 65%. This surpasses most previously reported efficiencies and possesses a shorter treatment duration and sustainable EDTA circulation. The mechanism analysis suggested that FNA pretreatment provoked the migration of heavy metals for leaching enhancement, as well as reduced the demand for EDTA eluent concentration and increased conductivity, which can improve the AACE efficiency. Meanwhile, the AACE process absorbed the anionic chelates of heavy metals and reduced them to zero-valent particles on the electrode, regenerating the EDTA eluent and maintaining its high extraction efficiency for heavy metals. In addition, FNA-AACE could provide different electric field operation modes, allowing it to have flexibility for the real application processes. This proposed process is expected to be coupled with anaerobic digestion in wastewater treatment plants (WWTPs) for high efficiency of heavy metal decontamination, sludge reduction, and resource/energy recovery.

Combined application of gamma radiation, cleaning and chemical sanitizers in decontamination of vehicle air conditioning filters

This work aimed to analyze the fungal contamination of air-conditioning filter waste (n=15) as an indicator of Quality Air Indoor from different car models in São Paulo city in São Paulo State, Brazil, during the period from October 2018 to July 2019. Three different treatments were used for the decontamination of car air conditioning filters, such as mechanical vacuum cleaning (I), vacuum cleaning and use of sanitizing product (II), and sanitizing product associated with radiation treatment at a dose of 17 kGy (III). After the treatments, microbiological analyses were performed and samples were plated in Petri dishes containing Sabouraud agar transferred by Swabs, and incubated for 7 days at 25 °C. The Petri dishes were stored in a standard Biochemical Oxygen Demand incubator, for the growth of fungal cultures. After incubation, the fungal cultures were evaluated, and the fungal counting was expressed in unit-forming colonies (UFC) and frequency in samples (%). The fungi were examined by lactophenol blue solution staining for microscopy. All samples of treatment I and II were contaminated with various fungal genera and high bioburden, namely (treatment I) Alternaria alternata, Aspergillus flavus, A. niger, Cladosporium spp., Fusarium spp., Mucor spp., Nigrospora spp., Not Sporulated Fungi (NSF), Penicillium spp., Rhizopus spp., Rhodotorula spp., Trichoderma spp. and yeasts. Treatment II showed Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. ochraceus, Cladosporium spp., Mucor spp., NSF, Penicillium spp., Phoma spp., Rhizopus spp., Rhodotorula spp., Trichoderma spp., and yeasts. Treatment III presented NSF and yeasts, with 80% of material decontamination.

Evaluation of groundwater in aluminium slag disposal area

Aluminium slag waste is a residue from aluminium recycling activities, classified as hazardous waste so its disposal into the environment without processing can cause environmental problems, including groundwater pollution. There are 90 illegal dumping areas for aluminium slag waste spread in the Sumobito District, Jombang Regency. This study aims to evaluate the quality of shallow groundwater surrounding aluminium slag disposal in the Sumobito District for drinking water. The methods applied an integrated water quality index ( WQI) and heavy metal pollution index ( HPI), multivariate analysis (principal component analysis (PCA) and hierarchical clustering analysis (HCA)), and geospatial analysis for assessing groundwater quality. The field campaign conducted 40 groundwater samples of the dug wells for measuring the groundwater level and 30 of them were analysed for the chemical contents. The results showed that some locations exceeded the quality standards for total dissolved solids ( TDS), electrical conductivity (EC), and Al 2+. The WQI shows that 7% of dug well samples are in poor drinking water condition, 73% are in good condition, and 20% are in excellent condition. The level of heavy metal contamination based on HPI is below the standard limit, but 13.3% of the water samples are classified as high contamination. The multivariate analysis shows that anthropogenic factors and natural sources/geogenic factors contributed to shallow groundwater quality in the study area. The geospatial map shows that the distribution of poor groundwater quality is in the northern area, following the direction of groundwater flow, and is a downstream area of aluminium slag waste contaminants.