JOURNAL OF THE GHANA SCIENCE ASSOCIATION

Abstract: To ensure the safety and security of Nuclear and Other Radioactive Material (NRM) under regulatory control, and to mitigate the risks associated with illicit trafficking and potential malicious activities, an assessment was undertaken to evaluate the detection of NRM in imported cargo transiting through Ghana’s sole international airport. In the absence of a radiation portal monitor, a Radioisotope Identification Device (RID) was utilised for the screening process. A total of 648 containers were examined, of which 62 were determined to contain radioisotopes with the recorded equivalent dose rates ranging from 0.029 µSv/h to 0.417 µSv/h. Although the RID is a less optimal tool than radiation portal monitors for comprehensive cargo screening, its application, however, confirmed the presence of radiation in air cargo shipments. These findings raise concerns regarding the potential for illegal or illicit trafficking of NRM at Kotoka International Airport.

Keywords: Nuclear and Other Radioactive Material, radioisotope identification device, cargo screening, radiation detection, illicit trafficking, Kotoka International Airport.

Abstract: Pot size plays a crucial role in cowpea (Vigna unguiculata L.) growth and development under controlled conditions. In this screenhouse study, we compared small (4 L) and large (10 L) pots across 20 replicates using the IT90K-76 genotype. Plants in larger pots consistently outperformed those in smaller ones, showing 40.9% more leaves, 52.5% greater leaf area, and 55.5% heavier seeds, all statistically significant (P < 0.05). Root biomass nearly doubled, reinforcing the importance of soil volume for healthy root development. Interestingly, traits such as pod length and seed count per pod remained unchanged, suggesting genetic stability. These findings highlight how pot size can skew experimental outcomes and offer practical guidance for designing more reliable screenhouse trials, especially in legume breeding and pre-breeding programs.

Keywords: crop management, cowpea, legume, pot size, screenhouse experiment, soil volume.

Abstract: The Voltaian Basin (VB) is an onshore sedimentary basin in Ghana that covers most central parts of Ghana. Unlike other Neoproterozoic sedimentary basins, a comprehensive sedimentology, tectonic evolution, economic prospects, and paleontological evidence of the VB are either inconclusive or unknown. The stratigraphic sequence of the basin from drill core is also still unknown. Hence, the review highlights the general sedimentology and other elements of a petroleum system of the basin and how that can be leveraged in the assessments of the hydrocarbon prospects of the basin. This review adds to the general ongoing discussion on the basin’s, with a special emphasis on its hydrocarbon prospecting and generation potential. Records of fieldwork show a thick unit of reddish argillaceous facies intercalated with thin lenses of greenish shales in the Ejura area and black shales together with phyllites in the Mpraeso area. The Kodjari Formation has well-exposed carbonates and cherts. Greenish and grey shale units are also exposed in the Sabari area with indications of phytoclasts and palynomorphs assemblage. Features of tectonic impact on the basin are reflected as microfolds, fractures, and faults. The organic geochemical indications from outcrop samples are suggestive of the presence of hydrocarbons, although very low. The hydrocarbon signatures observed from organic geochemical analysis of outcrop samples will require further investigations to ensure a comprehensive understanding of the basin evolution and the hydrocarbon prospects. Hence, the study recommends drill core samples should be used in the characterization of the petroleum system of the VB.

Keywords: Overview, sedimentology, paleontology, hydrocarbon prospects, Voltaian Basin, Ghana.

Abstract: Biochar has helped create possibilities for addressing the demand for environmentally acceptable and cost-effective adsorbents for adsorption. Removing phenol and polychlorinated biphenyl from landfill leachate is of great concern owing to the grave threat to soil, water resources and human health. This study investigated the efficiency of coconut husk biochar to adsorb phenol and polychlorinated biphenyl from landfill leachate. A total of 100 mL of the landfill leachate, with varied phenol and polychlorinated biphenyl initial concentrations, with contact times of 15, 30 and 45 minutes at temperatures of 30 and 35°C and coconut husk biochar dosage of 0.50, 1.50 and 3.50 g. The removal efficiency of up to 70.08% for phenol and 73.33% for polychlorinated biphenyl was achieved at adsorption conditions of 30°C and 35°C with contact times of 15, 30 and 45 minutes. The coconut husk biochar adsorption capacity (mg/g) of phenol ranged from 0.41 to 0.74 and 0.13 to 0.36 for polychlorinated biphenyl. The adsorbent dosage influences the adsorption efficiency significantly. The increase in adsorption efficiency as the adsorbent dosage increased might be attributable to the coconut husk biochar’s large surface area, which assisted in removing phenol and polychlorinated biphenyl from the landfill leachate. The adsorption efficiency decreased as temperature was increased from 30 to 35°C for phenol, whilst for polychlorinated biphenyl, the adsorption efficiency increased using coconut husk biochar. Pseudo-second order was the best-fit model for phenol and polychlorinated biphenyl onto the coconut husk biochar. This study is unique as it offers fresh perspectives on how temperature and dosage affect removal efficiency by using a sustainable agrowaste adsorbent to uniquely study two chemically distinct pollutants and disclose varied adsorption behaviours based on the compound characteristics. Coconut husk biochar has the potential for adsorption of phenol and polychlorinated biphenyl from landfill leachate. Furthermore, it emphasises the promise of coconut husk biochar as an environmentally friendly, affordable substance for treating complicated wastewater flows.

Keywords: Adsorption, polychlorinated biphenyl, coconut husk biochar, landfill leachate, phenol, pseudo-second order.

Abstract: Renewable energy is seen as a solution for reducing CO2 emissions and promoting sustainability. Ghana could increase renewable energy integration, but faces grid integration challenges and lacks an enabling environment for development. The full extent of renewable energy’s carbon reduction impact remains undocumented in Ghana, considering rapid globalization and population growth. This study examines renewable and non-renewable energy consumption’s impact on Ghana’s CO2 emissions from 1990 to 2020, using econometric methods. The analysis uses data from World Development Indicators, Global Footprint Network, and FAOSTAT to assess ecological footprint, fossil fuel use, forest land reduction, nuclear power, and renewable energy consumption. Results show fossil fuel use increases long-term CO2 emissions, while ecological footprints have short-term positive effects. Nuclear energy increases long-term emissions but reduces them short term, while renewable energy consistently reduces CO2 emissions in both periods. The study concludes all variables impact CO2 emissions in Ghana. Recommendations include implementing policies to promote renewable energy and limit emissions, introducing carbon tax on fossil fuels, and upgrading nuclear plants. As a Paris Agreement signatory, Ghana acknowledges nuclear power’s role in providing low-carbon energy. The government should incentivize renewable energy sources, invest in clean technology research, and conduct public awareness campaigns. Environmental education in schools can help educate future generations about sustainability.

Keywords: Carbon emission, ecological footprint, renewable energy.

Abstract: Mushrooms, despite their nutritional and medicinal attributes, are prone to microbial contamination, probably due to poor handling and preservation methods. The microbiological quality of fresh and dried edible mushrooms in the Ho Municipality was examined in this study. Per conventional protocols, bacteria tests were conducted on various media to quantify and identify pathogenic microbial species, including Salmonella, Escherichia coli, total coliforms, Staphylococcus aureus, and heterotrophic bacteria. Fresh mushrooms had a bacterial count ranging from 6.01–6.78 log10 CFU/g, whereas dry mushrooms had a count ranging from 5.68–6.64 log10 CFU/g. Fungal studies were performed on Dichloran Rose Bengal Chloramphenicol (DRBC) and Oxytetracycline Glucose Yeast Extract (OGYE) media at three different points per location. Nine different fungal species from seven different genera were isolated on both fresh and dried media. These species included Aspergillus (A. niger, A. fumigatus, A. alutaceaus, A. ochraceous), Rhizopus (R. stolonifer), Mucor (M. racemosus), Fusarium (F. oxysporum), Penicillium (P. digitatum), Trichoderma harzianum, and Rhodotorula sp. For fresh mushrooms, the range of fungal counts on both media was 3.56±1.1–4.35±0.92 and 3.32±0.93 log10 CFU/g, respectively. In terms of dry, 3.31±0.7–4.3±0.81 and 3.75±1.16–4.229±0.85 log10 CFU/g, respectively. The samples from various sites showed statistically significant (p < 0.05) differences. The pH readings for both fresh and dried samples fell between 6.62±0.09 and 6.83±0.08, and between 5.95±0.09 and 6.3±0.08. It can be concluded that the majority of mushrooms were acceptable for consumption according to the International Commission for Microbiological Specifications of Foods (ICMSF). This raises some public health concerns, as consuming those mushrooms increases the food safety risk in the Ho municipality.

Keywords: Fresh mushrooms, Dried mushrooms, Bacteria, Fungi, Contaminants, Ghana.

Abstract: Increase in population growth with a concomitant increase in economic activities, has seen the opening of many non-engineered dumpsites on the soil cover within the northern part of the Voltaian Sedimentary Basin (VSB). This is because non-engineered dumpsites are considered the cheapest and fastest way of waste disposal. However, the practice could have dire environmental consequences as toxic chemicals could be gradually leached into the shallow groundwater table resulting in contamination. To investigate the impact of the dumpsites on the shallow groundwater table, the electrical resistivity tomography technique (ERT) was deployed across some selected open (non-engineered) dumpsites in the Walewale municipality and Tamale metropolis in northern Ghana to map the possible flow of leachate below the subsurface. The results of the ERT sections revealed low-resistivity zones (< 20 Ωm) likely caused by migrating leachate from the waste piles or weathered clay soil underneath the dumpsites. This layer was interpreted as a possible leachate plume due to its spatial distribution and the comparatively low resistivity values relative to the background geology. The low-resistivity layers extend to depths averaging about 10 meters in the Walewale area which helped to define the vadose zone underneath the dumpsites. The geophysical results were corroborated with results from physicochemical and geoaccumulation index analysis of heavy metal concentrations on groundwater samples taken within a radius of 250 meters around the Walewale dumpsites. The study showed the concentration of total dissolved solids (TDS) and chloride (Cl-) fell within the permissible limits stated by the Ghana Standard Authority (GSA) and World Health Organisation (WHO) for all the samples except for sample GB04 where the TDS concentration exceeded the WHO permissible limit. Likewise, the concentrations of heavy metals such as Pb, Zn, Cu, and Cr were within the threshold limit set by the GSA and WHO for all the samples. However, the concentrations of Cd in samples WF 01, GB 02, NY 01, and KB 01 and Fe in samples GB 02, KB 01, and GB 05 all exceeded the recommended threshold values advised by GSA and WHO for potable groundwater for domestic purposes. The appreciable high levels of Cd and Fe in some of the samples cited could be anthropogenic due to their proximity to the non-engineered dumpsites. The dumpsites consist of plastic materials and metallic components which are major sources of Cd and Fe respectively.

Keywords: Dumpsite, Leachate, Contamination, Anomaly, Groundwater, Voltaian Sedimentary Basin.

Abstract: Cashew apple (CA) is a highly perishable and nutritionally rich pseudocarp that is commonly discarded as an agricultural waste despite its substantial ascorbic acid, dietary fibre, polyphenol, and mineral contents. This study evaluated the nutritional composition, °Brix indicators, colour parameters, and sensory acceptance of cashew apple fruit leather (CAFL) produced from five treatments with variation in cashew apple puree (CAP), honey and pectin concentrations: T1 (100% CAP: control), T2 (88.5% CAP, 10% honey, 1.5% pectin), T3 (88.0% CAP; 10% honey; 2.0% pectin), T4 (79.5% CAP; 20 % honey; 0.5% pectin), and T5 (79.0% CAP; 20% honey; 1.0% pectin). Nutritional analysis showed average moisture content of 11.08% dry weight basis (dwb) (T1) with water activity values between 0.52 at T1 and 0.76 for T3, under the condition of temperature at 25°C. The control formulation (T1) displayed the greatest content of dietary fibre (17.9%) and most favourable water activity (0.52), while honey-added formulations were characterised by a significantly higher level of °Brix: 39.7–40.4. pH was equally low, from 3.67 to 3.75, in all CAFLs. Vitamin C content varied between 2.27 and 3.05 mg/100 g dwb. Colour analysis revealed that the higher honey concentration formulations exhibited increased values of redness (a*) and chroma. Results of sensory evaluation showed that T4 (79.5% CAP + 20% honey + 0.5% pectin) had the highest acceptability score (6.1), and was superior to the control and formulations prepared with less honey in terms of taste, colour, aroma, and texture. The results indicated that adding 20% honey with 0.5% pectin recorded sensory quality with good physicochemical stability for CAFL. The findings of the study demonstrate a wider possibility of using honey and pectin as natural functional ingredients in the production of consumer-acceptable, fruit leather prepared from the cashew apple.

Keywords: cashew apple, fruit leather, honey, pectin, nutritional composition, sensory evaluation.

Abstract: Coastal erosion, driven by wave action, sea-level rise, and severe weather events threatens communities and infrastructure globally, yet effectiveness of coastal defence structures under climate change remains inadequately evaluated. This study quantified shoreline change rates along Ghana’s Dzita coast and assessed the impact of Atorkor-Dzita-Anyanui sea defence project over two decades (2001-2023), while exploring relationships between shoreline dynamics and climate-induced sea-level rise. Shoreline positions were extracted from LANDSAT 7 imagery using modified normalized difference water index (MNDWI) and sub-pixel contour mapping for pre-defence (2001-2014) and post-defence (2014-2023) periods. Annual growth/retreat values were compared against the 2023 baseline and correlated with global mean sea-level data using Spearman rank correlation. Pre-defence erosion averaged -4.0 ± 1.4 m/year indicating substantial retreat. Post-defence showed a net accretion averaging +1.7 ± 1.7 m/year, representing an improvement and demonstrating effective erosion mitigation. As documented in existing literature, the broader Keta Sea defence system has exacerbated downdrift erosion at Kedzi and Hlorve. Correlation analysis between shoreline changes and sea-level rise yielded inconclusive results (p-value = 0.5774), indicating a quasi-linear relationship influenced by complex interactions including human activities, sediment dynamics, and coastal infrastructure beyond sea-level rise alone. These findings demonstrate successful local-scale coastal protection while underscoring the need for comprehensive, adaptive coastal management strategies that account for both protective benefits and unintended downdrift impacts, providing data-driven insights for policymakers addressing climate adaptation challenges along sediment-starved coastlines.

Keywords: coastal erosion, sea-level rise, coastal defence effectiveness, satellite remote sensing, Digital Earth Africa.

Abstract: Local site conditions can significantly influence earthquake ground motion, increasing potential damage to buildings and infrastructure. The soils in the Greater Accra Metropolitan Area (GAMA) have complex lithologies with varying distributions, primarily due to the influence of bedrock, drainage, and topography. The history of damaging earthquakes, combined with the rapid expansion of urban development in the region, has further increased the exposure to seismic risk. The study aims to assess site effects and seismic vulnerability in this region using the horizontal-to-vertical spectral ratio (HVSR) analysis on passive ambient noise from 13 sites. The analysis reviewed key parameters including the fundamental site frequency (0.73 – 11.02 Hz), amplification factor (1.66 – 9.94), alluvium thickness (2.61 – 175.75 m), and soil vulnerability index (0.37 – 20.00). Tesano PS was identified as the most vulnerable site to earthquake destruction and liquefaction, reflecting its softer and thicker alluvial soils. In contrast, Lapaz exhibited a comparatively low seismic response, consistent with stiffer rocks with no amplification. Aburi, on the other hand, exhibited a low seismic response consistent with its shallower soils and more competent, rocky subsoil. These findings highlight the need to integrate site-specific parameters as determined above into land-use planning and the design of earthquake-resistant infrastructure in Accra.

Keywords: Earthquake, Site effects, HVSR, Ambient noise, Fundamental frequency, Amplification factor, Vulnerability index, Greater Accra Metropolitan Area.