Determination of heavy metal elements concentration in soils and tailing sediments from lateritic nickel post-mining areas in Motui District, Southeast Sulawesi

Heavy metal elements concentration study has been determined from soils and tailing sediments in laterite nickel post-mining area in Motui District Southeast Sulawesi. This study aimed to determine the concentration of some heavy metal elements, especially Fe, Co, Mn and Cr, from surface soils sediments in waste dump sites and tailing sediments in settling ponds from lateritic nickel post-mining areas. A total of 20 samples consisting of 18 soil samples and 2 tailing sediments samples were systematically collected for the study. The soil samples from the waste dump site profile were collected from 3 layers which were divided based on the colour of the soils from top to bottom, namely Layer C, Layer D and Layer E. Six soil samples were taken from each layer with space between each sample in one layer was about 50 – 60 cm. The samples were sent to the laboratory and analysed using Atomic Absorption Spectrometer (AAS) method to determine the concentration of heavy elements. Metal-bearing minerals detected from the bedrock consists of chromite, manganese, magnetite and limonite which are responsible for the Cr, Mn and Co, and Fe content, respectively. The result showed that Fe content is significantly higher in soil samples from Layer C and tailing sediments with dark red to brown in colour, suggesting the strong relation between Fe content and colour index. The general element mobility trend showed that Mn and Co are positively correlated in soil sampling from all layers and tailing samples, whereas Fe and Cr show a negative correlation trend in Layer C, D and tailing sediments but positively correlated in Layer E.

Effect of Calcination on the Chemical and Microstructural Properties of Sugarcane Bagasse Ash (SCBA)

This research study is for the evaluation of the effect of the burning temperature on the chemical and microstructural properties of Sugarcane Bagasse Ash. The Sugarcane Bagasse Ash (SCBA) is a byproduct of sugarcane which is dumped without proper handling and causing environmental issues because of the burning on dump site and loss of the area due to dumping in the commodity. The current research study is conducted for burning of SCBA on different temperatures and duration for finding the optimum burning temperature and duration of burning. The chemical and microstructural properties of SCBA evaluated at burning temperatures of 800°C for the duration of 01 hour, at temperature of 600° for the duration of 03 and 06 hours by conducting the tests of FTIR, XRD and XRF on the samples. The test results show that the burning temperatures of 800°C for the duration of 1 hour contains amorphous silica and also fulfilling the requirement of pozzolanic material (Composition of Silica, alumina and iron oxide is greater than 70%) as compared to other ash samples of sugarcane bagasse.

Molecular Characterization of Fungi Associated with Dump Site Soil

Aims: A study was conducted to identify fungal species isolated from dumpsite soil in University of Port Harcourt using molecular techniques. Methodology: Molecular methods for determining the species of a fungus based on the amplification and sequencing of the internal subscribed spacer (ITS) region of the fungal rRNA operon using molecular markers was applied. Soil sample was collected from a dumpsite in the University of Port Harcourt, Rivers State, Nigeria. Isolation of fungi associated with the dumpsite soil was carried out using spread plate method. Fungal genomic DNA was extracted using Quick-DNA Fungal/Bacterial Miniprep kit. The ITS1-2 gene of the isolates was amplified by Polymerase Chain Reaction (PCR) using the primer pair; ITS4 and ITS5. Results: The sequences of the amplified ITS region were blasted against known sequences on the National Centre for Biotechnology Information (NCBI) database. Nucleotide sequence analysis revealed the species identity of the fungal isolates to be: Aspergillus fumigatus, Trichoderma harzianum, Aspergillus felis, Aspergillus templicola, Aspergillus flavipes, Aspergillus fumigatus and Cunninghamella binariae. Phylogenetic analysis was carried out to ascertain the relationship between the isolates and other closely-related isolates on GenBank. Isolates 2 (Trichoderma harzianum) and 7 (Cunninghamella binariae), 3 (Aspergillus felis) and 6 (Aspergillus fumigatus), and 4 (Aspergillus templicola) and 5 (Aspergillus flavipes) were found to be more closely related to each other. Conclusion: The molecular techniques employed successfully identified the organisms to the species level as these techniques are based on the genetic constitution of organisms. The result obtained from this study will complement the information on the fungal organisms associated with dumpsite soil.

Effects of Plastic Pollution of Soil on the Growth and Survival of Bacteria and Fungi

The study examined the effect of plastic waste on soil bacteria and fungi. The test soil samples were collected from Lokoja international market waste dump site and the control soil sample was collected from non plastic contaminated garden in Salem University, Lokoja. The samples were analysed using Gas chromatography with mass spectrometer. The test soil sample soil sample had high quantity of plastic contaminant which were Methylene chloride 17.45mg/kg, hexane 10.05mg/kg, chloroform 1.56mg/kg, toluene 5.87mg/kg, tetrachloroethylene 1.48mg/kg as compared to the control garden soil sample, which had methylene chloride 0.54mg/kg, hexane 0.26mg/kg, chloroform 0.31mg/kg, toluene 5.87mg/kg and tetrachloroethylene 0.01mg/kg. The result showed the presence of plastic in the soil and it effect on bacteria and fungi. The totals of 11 bacteria were isolated from both soil samples using nutrient agar. The bacteria isolated are; Corynebacterium spp. (12%), Enterobacter spp. (8%), Acinetobacter spp. (6%), Escherichia coli (16%), Epidermis, Bacillus subtilis (15%), Serratia sp. (8%), Proteus spp. (4%), Micrococcus luteus (7%), Flavobacterium spp. (10%), Pseudomonas aeruginosa (15%). Micrococcus luteus, Flavobacterium spp. and Pseudomonas aeruginose were not isolated in plastic composted soil sample due to the presence of plasticizers. The total of 6 fungi were isolated, namely Penicilliun expansion (12%), Sacchromyces sp. (24%), Aspergillus niger (19%), Fusarium spp. (20%), Rhizopus stolonifer (10%) and Mucor piriformis (15%). This study reveals the effect of plastic waste, as it inhibits the growth of microorganism that is important for soil activities, thereby reducing the soil nutrients, fertility and productivity.

Deep impact? Is mercury in dab (Limanda limanda) a marker for dumped munition? Results from munition dump site Kolberger Heide (Baltic Sea)

Dumped munitions contain various harmful substances which can affect marine biota like fish. One of them is mercury (Hg), included in the common explosive primer Hg fulminate. There is still a lack of knowledge whether dumped munitions impact the Hg concentrations in the Baltic Sea environment. This study aims to answer the question if dab caught at the dump site Kolberger Heide show higher Hg concentrations released from munition sources and whether Hg in fish is a usable marker for munition exposure. Therefore, a total of 251 individual dab (Limanda limanda) were analysed including 99 fish from the dump site. In fish from the Kolberger Heide, no elevated Hg concentrations were found compared to reference sites when age-dependent bioaccumulation of mercury was considered. Therefore we conclude that Hg in fish is no suitable indicator for exposure to munition dumping, e.g. in the frame of possible future monitoring studies as Hg exposure originating from dumped munition is only a small contributor to overall Hg exposure of fish.

Environmental Implications of Municipal Dump Site on Soil Nitrogen in Calabar Metropolis, Nigeria

Organic matter exhibit strong variations in nitrogen retention and transformation cycle in soil. However, nitrogen could be altered by seasonal variations, leading us to hypothesize that the open municipal waste dump site in Calabar exposed to dry and wet season could alter nitrogen dynamics in that soil. A total of sixty (60) composite soil samples were collected at different landscape positions (summit crest, shoulder slope, toe slope, interfluve slope, valley floor) of a municipal dump site and a control (no refuse area) during the dry and wet seasons in Calabar and analyzed to ascertain the effects on forms and status of soil nitrogen. The soils were loamy sand across the study location with pH values of 4.50, 7.00, 6.70, 7.30, 5.00, 7.30 (dry season) and 5.00. 7.30, 7.00, 7.40, 5.90, 7.40 (wet season) for the control, summit crest, shoulder slope, toe slope, interfluve slope and valley floor accordingly. Values obtained for total nitrogen (N) from the study site were generally low (<0.21 %), with values for dry season slightly higher than the wet season. NH4+ recorded higher content in wet than in dry season with values ranging between 12.11-14.11 mg/kg (control), 14.60 - 15.90 mg/kg (Summit crest); 18.25 - 20.05 mg/kg (Shoulder slope), 18.30 - 20.20 mg/kg (Toe slope), 12.30 - 14.00 mg/kg (Interfluve slope) and 9.24 -11.07 mg/kg (Valley floor). The Shoulder and toe slopes recorded the highest NH4+ concentration in the wet season. N02- contents documented for the control site were within the ranges of 2.78- 3.20 and 3.22-3.62 mg/kg while the dumpsite had values between 2.49-3.45 and 2.98 -3.22 mg/kg was observed for the shoulder position, the toe slope contained between 2.30-2.75 and 2.70 -2.82 mg/kg, the inter fluve slope had similar ranges of 2.32-2.90 and 2.70-3.08 mg/kg, and the valley floor 2.45-2.60 and 2.78-2.98 mg/kg. N02- values were higher for the wet than dry season. NO3- nitrogen was observed to be excessive across the dumpsite with the highest values > 80 mg/kg obtained at the valley floor. The NO3- values were higher in dry season across the all the landscape positions than in the wet season. The values were equally higher for the dumpsite than the control. It was observed that the dumpsite soils contend excessive NO3- which could be converted to nitrous oxide (N2O) thus contributing to green house (GHG) emissions. It was also noted that seasonal variation did not significantly affect the N content at the different landscape positions of the municipal dumpsite in Calabar. It is highly recommended that municipal waste be sorted and the organic materials composted to harness the rich NO3- content as observed in this research. Received: 22 September 2021 / Accepted: 25 October 2021 / Published: 5 November 2021

Scientific Analysis of Firing Characteristics for Walls and Rooftiles Excavated from Jeseoksa Dump-site, Iksan

In this study, the physicochemical properties of 21 wall fragments and rooftile pieces excavated from Jeseoksa Dump-site were analyzed, and the possibility of heat exposure, such as the fire reported in the literature, was investigated by estimating the firing temperature. From the results, it was estimated that the rooftiles were composed of refined materials, and the walls were composed of materials having different particle sizes depending on the layer. Unlike ordinary rooftiles and walls, they exhibited an uneven surface with traces of bloating phenomenon in the cross section. It was estimated from the blackening of some portions that firing was not performed in a controlled state in a constant firing environment. In addition, the estimated firing temperature showed that the non-overfired rooftiles had endured a firing temperature of 900°C or less, but the over-fired samples were subjected to a temperature of 1,000°C or higher and were fired at a temperature higher than the manufacturing temperature at that time. Additionally, the rooftiles probably became defective during firing or molding at the time of production, but the non-overfired rooftiles exhibited an intact shape and showed the possibility of heat exposure due to fire. Therefore, the analytical results of this study confirm that the defective architectural components damaged by the fire, as reported in the literature, were discarded in the Jeseoksa dump-site.

Application of Crude Enzymatic Extract In Mushroom Processing To Recover High Value Products

In the present study, a fungal strain was isolated from mushroom waste dump-site and was described based on the morphological and molecular characteristics. The crude enzymatic extract was prepared by fermenting pineapple peels using the newly isolated fungal strain under solid-state condition. The enzymatic saccharification conditions of mushroom were optimized using the central composite design based on the response surface methodology. The isolate had black colony color, conidial head biseriate and small conidia which are synonymous with Aspergillus niger. The phylogenetic analysis using the rDNA ITS sequencing further revealed that the isolate was identical (≥99%) to A. niger. The crude extract displayed CMCase, Fpase and xylanase activities of 20.73U/mL, 34.57U/mL and 118.03U/mL respectively. The saccharification using the crude extract at optimal conditions of pH 6.5, temperature 50oC, enzyme loading of 5% (v/v) and time of 12h achieved maximum glucose yield of 1.639 mg mL-1 which is 1.1 folds higher than the predicted value. This study demonstrated the potential use of crude enzymatic extract from the newly isolated A. niger as a viable and efficient low-cost approach to mushroom processing using enzymes.

HIV, HBS and HCV in Dump Site Workers of Erbil Governorate

This research targeted eighty-nine males working in Kany Qrzhala, dumpsite. Age and gender comparable apparently healthy subjects were selected as healthy controls, and both of the groups were obliged to fill the study's questionnaire. Further, venous blood samples were collected from each individual for serum collection. The accumulated sera reserved for the sero-prevalence for antibodies tests of Human Immunodeficiency Virus, Hepatitis B Surface Antigen and Hepatitis C Virus, (HIV), (HBS), (HCV) respectively. The automated immunoassay analyzer Cobas E411 facilitated the conducting of the mentioned tests. The serum concentration of HIV and HBS antibodies of dumpsite workers revealed a significant increase when compared to the healthy group, while the HCV antibody serum concentration presented no significant alteration when comparing dumpsite workers to the healthy controls. The antibodies presence in the sera that belonged to workers is an indicator of exposure to the viruses due to unsanitary health conditions. This may pose a public health risk to the workers themselves, in addition to the people they are in contact with, including their families.