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Item Prevalence of Commonly Consumed Drugs in Mbarara City, Uganda(EAST AFRICAN NATURE & SCIENCE ORGANIZATION, 2026-02-23) Habimaana, Samuel,; Kemigisha ,Chalrotte; Nnamuyomba, Proscovia; Ntambi Emmanuel; Adaku ,ChristopherPharmaceutical consumption is rising globally, with significant implications for environmental pollution and antimicrobial resistance (AMR). In sub-Saharan Africa, weak prescription control, widespread self-medication, and insufficient wastewater treatment amplify risks of pharmaceutical residues entering aquatic systems. Studies in Uganda have detected active pharmaceutical ingredients in urban waters, including River Rwizi, a critical domestic and agricultural water source for Mbarara City. However, systematic data linking patterns of drug consumption to environmental risks in Mbarara City remain scarce. Through a descriptive cross-sectional survey, drug use prevalence across public and private healthcare outlets in Mbarara City was assessed, focusing on 30 essential medicines listed in the Uganda Clinical Guidelines (2023). Data was collected from 81 drug outlets in strategically selected clusters adjacent to the River Rwizi and analysed using descriptive statistics. Results show extremely high prevalence of paracetamol (97.5%), amoxicillin (96.3%), ibuprofen (93.8%), azithromycin (86.4%), ciprofloxacin (82.7%), metronidazole (84.0%), coartem (80.2%), eftriaxone (77.8%), and doxycycline (76.5%), indicating a narrow subset of medicines that dominate urban consumption. These drugs address the city’s burden of febrile illnesses, malaria, and bacterial infections, but their widespread and unregulated use heightens risks of AMR development and pharmaceutical pollution. The findings indicate an urgent need for integrated pharmaceutical stewardship, improved wastewater treatment, and environmental monitoring of the River Rwizi. By establishing a baseline of commonly consumed drugs in Mbarara City, this study provides essential evidence for guiding rational drug use policies, waste management strategies, and interventions to safeguard both public health and aquatic ecosystems.Item Liver and renal biochemical profiles of people with sickle cell disease in Africa: a systematic review and meta-analysis of case-control studies(MBC., 2023-08) Awor Silvia; Bongomin Flexi; Kaggwa Mark Mohan; Pebalo Francis; Epila Jackie; Malinga Geoffrey Maxwell; Oryema Christine; Nnamuyomba Proscovia; Abola Benard; Ongwech Acaye; Musoke DavidBackground Sickle cell disease (SCD) is a genetic blood disorder characterized by a painful vaso-occlusive crisis due to the sickling of red blood cells in capillaries. Complications often lead to liver and renal dysfunctions, contributing to morbidity and mortality, particularly for children under 5. This systematic review and meta-analysis aimed to evaluate the liver and renal functions of people with SCD (HbSS) compared to those without it (HbAA) in Africa. Methods The protocol was registered with PROSPERO (CRD42022346771). We searched PubMed, Embase, Web of Science, and Google Scholar using the keywords “liver function”, “renal function”, “sickle cell disease”, and “Africa” on 6th May 2023 for peer-reviewed articles with abstracts in English. We included case-control studies comparing SCD (HbSS) with controls without hemoglobinopathies (HbAA). We used the random-effect model to calculate the pooled average values for the blood tests of people with SCD in RStudio version 4.2.2. Results Overall, 17 articles were analyzed from five African countries involving 1312 people with SCD and 1558 controls. The pooled mean difference of liver enzymes aspartate transaminase (AST) was 8.62 (95% CI − 2.99–20.23, I2 = 97.0%, p < 0.01), alanine transaminase (ALT) 7.82 (95% CI − 0.16–15.80, I2 = 99%, p < 0.01) and alkaline phosphatase (ALP) − 2.54 (95% CI − 64.72 – 59.64, I2 = 99%, p < 0.01) compared to controls. The pooled mean difference for the renal biochemical profiles creatinine − 3.15 (95% CI − 15.02; 8.72, I2=99%, p < 0.01) with a funnel plot asymmetry of t = 1.09, df = 9, p = 0.3048 and sample estimates bias of 6.0409. The pooled mean difference for serum urea was − 0.57 (95% CI − 3.49; 2.36, I2 = 99%, p < 0.01), and the estimated glomerular filtration (eGFR) rate was 19.79 (95% CI 10.89–28.68 mL/min/1.73 m2, I2 = 87%, p < 0.01) compared to controls. Conclusion People with SCD have slightly elevated liver enzymes and estimated glomerular filtration rates compared to controls in Africa. With all the heterogeneity (I2) > 50%, there was substantial variation in the reported articles’ results.Item Trace Elements in Marketed Rastreneobola Argentea and Clarias Werneri Caught from Selected Aquatic Ecosystems in Uganda(International Journal of Current Trends in Engineering & Technology, 2015-08) Nnamuyomba, Proscovia; Mbabazi, Jolocam; Ntale, MuhammadSamples of two fish species Rastreneobola argentea and Clarias werneri from Lake Victoria, Lake Kyoga and Nakivubo and Lubigi wetlands were analysed for Cu, Zn, Pb and Cd using an Atomic Absorption Spectrophotometer - Perkin-Elmer Model 2380. The results revealed that Zn concentrations were the highest in both species, followed by Cu; Pb and Cd being the lowest. The concentrations of Cu, Zn, Pb and Cd in R. argentea from Lake Victoria ranged between 20.5- 115 µg/Kg, 175 - 495 µg/kg, 15 - 77.5 µg/Kg and 2.5 - 4.45 µg/kg respectively, mean while their concentrations in the same fish species from Lake Kyoga ranged between 12.5 - 37.5 µg/kg (Cu), 35-100 µg/kg (Zn), 5-12.5 µg/kg (Pb), 0.5-1.5 µg/kg (Cd) dry weight. In C.werneri, heavy metals varied between 197-337.5 µg/kg (Cu), 235-670 µg/kg (Zn), 60-77.5 µg/kg (Pb) and 2.5-6.98 µg/kg (Cd) in Lubigi wetland and in Nakivubo wetland, concentrations of heavy metals ranged between 7521320 µg/kg for Cu, 1230-1437 µg/kg for Zn, 85-97.5 µg/kg for Pb and 2.2-7.75 µg/kg for Cd. Heavy metal concentrations obtained in this study were below permissible limits issued by WHO/FAO. Therefore, the consumption of these fish species may not pose any threat to human health. However periodic monitoring of these metals in the fish caught from water bodies located in urban areas is highly essential to public healthItem "We Cure Sickle Cell Disease with Herbs”: Perspectives of Herbal Medicine Practitioners Treating Sickle Cell Disease in the Acholi Sub Region(Doverpress, 2025-07-28) Awor, Silvia; Opee, Jimmyy; Ocaya Denis; Ocaya Jimmy; Abola Benard; Malinga, Geoffrey Maxwell; Oryema Christine; Arwenyo, Beatrice; Ongwech Acaye; Musoke, David; Nnamuyomba Proscovia; Epila JackieSickle cell disease (SCD) is a genetic blood disorder that results in the deformation of red blood cells under low oxygen conditions, causing vaso-occlusive crises and severe complications. While hydroxyurea has been Introduced as a treatment for SCD, herbal medicines remain widely used across Africa. Northern Uganda has a high SCD prevalence of 20.5%, yet limited research exists on alternative treatment options within local communities. This study aimed to explore the perspectives of herbal medicine practitioners in the Acholi sub-region. Methods: We conducted in-depth interviews between October and December 2024 involving 24 herbal medicine practitioners in the Acholi sub-region, selected through referrals and non-probability snowball sampling. All data collected were recorded, transcribed verbatim, and analyzed using thematic content analysis, and emerging themes were presented. Results: All participants believed herbal medicine could cure SCD, and the majority reported successfully treating patients. However, some practitioners remembered some patients who reported being sick with sickle cell crises many years after the “cure”. “When they report improvement, I stop medication after some time…” thereafter, “I encourage them to go to the hospital, but they do not. They can stay without falling sick for a long time and declare themselves healed”. Findings suggest herbal medicines are commonly used for SCD management in the Acholi sub-region. Most herbal medicine practitioners rely on the hospital diagnoses, although a few can tell who has sickle cell disease by looking at or touching them. A lot of mistrust exists between herbal medicine practitioners, the government, and researchers. This hinders efforts to integrate traditional medicine into mainstream healthcare and limits opportunities for scientific validation. Conclusion: Herbal medicine practitioners believe herbs can treat sickle cell disease; however, further research is needed to investigate the nature of these herbs and their mechanisms of action, thereby facilitating the integration of herbal medicine into conventional care. We discuss some implications of the study for practice and policy.Item Safety and efficacy of herbal medicines for the management of sickle cell disease in Africa: a systematic review and meta-analysis(PMJ ONE HEALTH, 2024-12-16) Awor, Silvia,; Bongomin Felix; Kaggwa Mohan ,Mark; Pebalo, Francis; KivumbiMuganga, Ronald; Malinga, Geoffrey Maxwell ,; Acaye Ongwech; Nnamuyomba, P; Oryema, Christine; Abola, B; Epila, J.; Musoke, DavidThis systematic review and meta-analysis evaluated the safety and efficacy of herbal remedies used to manage sickle cell disease (SCD) in Africa. Before the advent of western medicine, people depended on herbal medicines for treating different illnesses. Using herbal medicines to sickle cell disease (SCD) is still common in Africa. However, data on the safety and efficacy of any of these remedies are limited. We searched PubMed, Embase, Google Scholar and Web of Science from inception to 11thJanuary 2024 using the keywords "herbal medicine" and "sickle cell" and the name of each of the countries in Africa without language restrictions. We included cross-sectional studies that reported the safety or efficacy of herbal medicine for managing sickle cell disease. Two reviewers assessed all included studies for suitability for inclusion in this review. All included articles were assessed using ROBINS-1, a tool for assessing the risk of bias in non-randomized studies of interventions. We used the random effect model to pool the efficacy and safety profiles of the herbal medicines using RStudio version 4.2.2. Overall, we included five studies involving 1,489 individuals with SCD. Of these, 789 (53.0%) used herbal remedies like Aloe barbadensis (Aloe vera), Zingiber officinale (ginger), Cymbopogon citratus (lemongrass), Forever Living products, Golden Neo-Life Diamite International (GNLD) diet supplements and ginseng products. About 22.9% (181 out of 789) of the participants who used herbal remedies reported side effects, while 38.5% (304 out of 789) reported improving their symptoms. There was a high risk of publication bias in the articles included in this review. The pooled adverse effects of the herbal medicines for SCD treatment were 48% lower (Odds ratio: 0.52, 95% confidence interval (CI): 0.26 - 1.05, I²= 82%, p<0.01) while the pooled efficacy of herbal remedies for treating SCD was nearly 100% higher (odds ratio= 2.07, 95% confidence interval 0.99 - 4.32, I²= 78%, p<0.01) among the users than controls. However, these findings were not statistically significant. Our findings indicate no significant difference in the safety and efficacy of herbal medicines among people with SCD who used or did not use herbal remedies. However, the sample sizes of the primary studies were small. Thus, more extensive controlled studies with better-defined endpoints are required to inform the use of herbal medicines in managing SCD in Africa.Item Effects of environmental temperature on the growth performance of a tropical Oreochromis esculentus (Graham, 1928). Implications for the species conservation(Willey., 2022-09-14) Nagayi, Kalule Yawe jane; Kisakye Joseph; Tenywa Mwanja Matthew ,; Nattabi. Juliet; Opio AlfonseClimate variability and change are currently recognised global challenges. However, the impacts of rising temperatures may be greatest on tropical freshwater fish, which already exist in warm environments and may be living close to their critical thermal maximum. However, there is limited species- specific information on tropical species’ adaptive capacity to increased temperature. This study examined various growth attributes in juvenile populations (farmed, L. Kacheera and L. Nabisojjo) of a critically endangered tropical Oreochromis esculentus to determine its adaptive potential. Fish were acclimated at 25, 28, 31 and 34°C for 28 days. Overall, survival rates were high. Growth coefficient b was not significantly different from three (b = 3) in all treatments, implying isometric growth. The specific growth rates (SGRs), body condition K, and hepato- somatic indices (his) declined as the acclimation temperatures increased. Although SGR showed significant variations only among populations, the highest in L. Nabisojjo, K and HSI showed significant variations among treatments. Overall, the growth attributes declined at higher acclimation temperatures, but remained within acceptable ranges, implying that the species may attain normal growth at elevated temperatures experienced in outdoor aquaculture systems, despite its warm environmental background. Hence, we recommend selective breeding for temperature resilience and species introduction into aquaculture using broodstock from L. Nabisojjo.Item Dichloro-diphenyl-trichloroethane (DDT) residue levels in marketed Silver Fish (Rastreneobola argentea) caught from major water bodies in Uganda(Academic Journal, 2014-06-25) Nnamuyomba, Proscovia; Mbabazi, Jolocam; Ntale MuhammadSilver fish (Rastreneobola argentea) samples from Lake Victoria and Lake Kyoga were analyzed for dichloro-diphenyl-trichloroethane (DDT) and metabolites using a Gas Chromatograph equipped with an Electron Capture Detector. Confirmation of results was by Gas Chromatography equipped with Mass Spectrophotometer (GC-MS). DDT and metabolites were detected in 90% of the total samples (63 out of 70). pp’ DDT was the most frequently detected residues in the samples whereas op’ DDE was detected in none of the samples. The mean ΣDDT concentrations in fish from Lake Victoria varied from 0.147 to 0.396 µg/kg while that in Lake Kyoga varied from 0.207 to 0.506 µg/kg dry wt of fish sample. The concentration of total DDT in the fish samples ranged from 0.147 to 0.506 µg/kg dry wt. This was far below the recommended FAO limit of 5000 µg/kg for fish (edible portion), implying that the fish are safe for human consumption.Item 1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its derivatives in marketed Clarius werneri caught from Uganda’s major urban wetlands(Journal of Toxicology and Environmental Health Sciences, 2014-07-29) Nnamuyomba, Proscovia; Jolocam Mbabazi; Muhammad NtaleThe presence of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and derivatives in the Clarius werneri of Uganda’s major urban wetland ecosystems was investigated. Solid dispersion extraction method for extraction, florisil column method for clean-up, gas chromatograph equipped with an electron capture detector (GC-ECD) for analysis and gas chromatograph equipped with mass spectrophotometer (GC-MS) for confirmation of results were used in this study. The major DDT contaminants detected in the samples were p,p’-DDD, p,p’-DDE and p,p’-DDT which were found in 25, 22 and 21% of the samples, respectively. o,p’-DDD was detected in 19% and o,p’-DDT in 13% of the samples. For o,p’-DDE there were no measurable values since the levels were below limit of quantitation (LOQ). The concentrations of DDT derivatives ranged between ND-0.478 µg/kg for p,p’-DDE, ND-0.387 µg/kg for o,p’-DDD, ND-0.476 µg/kg for p,p’-DDD, ND-0.345 µg/kg o,p’-DDT and ND-0.556 µg/kg for p,p’- DDT. The concentration of total DDT in C. werneri was in the range of 1.111 to 1.328 µg/kg dry wt. Generally, all the samples had DDT derivative levels below the maximum residue limit recommended by Food and Agriculture Organisation/World Health Organization (FAO/WHO) Codex Alimentarius Commission.Item Water Bactericidal Properties of Nanosilver- Polyurethane Composites(Nanoscience and Nanotechnology., 2011) Mulongo George; Mbabazi Jolocam; Proscovia Nnamuyomba,; Song Hak-CholA technique for coating polyurethane with silver nanoparticles freshly prepared using a hydroxyethyl cellulose organic polymer is presented. The ensuing silver nanoparticle – polyurethane foam composite is found to possess such antibacterial properties as might be useful in water disinfection. With the help of electron microscopy and FTIR spectrophotometry, it was revealed that the adsorption of metallic silver onto the organic polymeric substrate could be attributed to silver nanoparticulate interaction with the nitrogen in the ─NH─ bond in polyurethane. Contrary to earlier reports that similar preparations had total bactericidal effects on water-borne microorganisms, a number of microbial analyses performed on Basillus Subtulis 15 and E. coli 36 as test bacteria in infected waters exhibited only 9 and 5 live percentages, respectively, after eluation through the composite-packed column.Item Dichlorodiphenyltrichloroethane (DDT) and its metabolites in house dust, soil and selected food crops from indoor residual sprayed areas of Apac and Oyam Districts, Uganda(African Journal of Pure and Applied Chemistry, 2022-06-12) Mukasa paul; Wasswa John; Namuyomba Proscovia; Ntambi EmmanuelDichlorodiphenyltrichloroethane (DDT) levels and its metabolites are reported in 75 soil and 75 vegetable samples from the vicinity of homesteads sprayed with DDT during indoor residual spraying (IRS) pilot exercise, carried out in 2008 in Apac and Oyam districts, Uganda as a measure to control malaria. The samples were randomly and conveniently collected in 2020 from selected villages of the districts, extracted using solid dispersion and multi-residue methods for soil and vegetable samples, respectively and analyzed using GC-ECD and GC-MS. DDT residues were detected in all samples collected. The ΣDDT (µg kg-1) in all indoor house dust, outdoor soil samples from villages of Apac and Oyam districts and control areas were 69.9±20.9 and 8.9±4.7, 113.4±22.6 and 15.4±4.3, and 1.13±0.27 and 1.8±0.9, respectively. ΣDDT were significantly higher (p < 0.05) in the study areas than the control areas. In vegetables, ∑DDT (µg kg-1) ranged between 1.7±0.3 and 8.3±4.0 and 2.3±0.4 and 11.4±7.5 in the study and control areas, respectively. Abelmoschus esculentus and Gynandropsis gynandra had the highest levels. The results suggest that IRS had an effect on DDT levels in the environment. However, ∑DDT in vegetables were significantly below (P < 0.05) the EU EMRL, thus, the results raise no concern regarding the potential health effects of DDT to the residents. Nevertheless, due to bioaccumulation effects of DDT, to control malaria, measures like Ecohealth rather than IRS of DDT should be embraced.Item Organic Explosive Residues from Demining Sites in Amuru District, Northern Uganda(Scientific Research Publishing, 2025) Ocaya, Jimmy; Arwenyo,Beatrice; Ongwech , Acaye; Nnamuyomba , Proscovia; Opio , Alfonse; Angwech ,Harriet; Kisitu , JaffarThe study investigated the occurrence of explosive compounds at four demining sites in Amuru District, Northern Uganda. The concentrations of explosive compounds octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 2,4,6-Trinitrophenyl-n-methylnitramine (tetryl), 2,4,6-trinitrotoluene (TNT), 2,6-dinitrotoluene (2,6-DNT),cyclotrimethylenetrinitramine (RDX), nitroglycerin (NG) and Pentaerythritol tetranitrate (PETN) in soil samples collected from the demining sites were determined by liquid chromatography-tandem mass spectrometry with atmospheric pressure chemical ionization (LC-MSMS-APCI). The LC-MSMS-APCI method was optimized and validated. The validation parameters included were accuracy, precision, recovery, linearity, selectivity, limits of detection, and limits of quantification. The limit of detection and quantification of the target analytes ranged from 4.5 - 32.1 ng·mL−1 and 17 - 102.9 ng·mL−1, respectively. Recovery of the target analytes from the soil samples ranged from 76% - 96%. The intra- and inter-day accuracy and precision values of below 15% indicated that the target analytes could be determined with reasonable accuracy and precision using the optimized method. The target analyte concentrations in soil samples ranged from 24.6 to 551.8 μg·g−1 with RDX and TNT being dominant. All the soil samples analyzed had explosive residue concentrations higher than the set chemical contamination values set by the US EPA PRGs Region 9 for Soil Screening Levels.Item Analysis of the Application of the Discovery Learning Model to Students' Creative Thinking Ability in Reaction Rate Material(Indonesian Journal of Education Research (IJoER), 2023-08-28) Niski Nadila1, 2,; Louis-Charl Cloete Coetzee; Beatrice ArwenyoPurpose of the study: The purpose of this study was to describe and determine the relationship between the implementation of the discovery learning model in the matter of the rate of reaction with the students' creative thinking abilities. Methodology: This research is a type of correlational descriptive research. The sampling technique used in this study is Simple Random Sampling. The instrument used in this research is the observation sheet. Data analysis techniques using normality and homogeneity tests. Main Findings: The results of this research are that the application of the Discovery Learning model to reaction rate material can be carried out very well. This is because the teacher corrects errors in applying the model at the next meeting and there is a relationship between the application of the Discovery Learning model and students' creative thinking abilities in the reaction rate material in class XI in the medium category. Novelty/Originality of this study: Provide information about the implementation of discovery learning learning models and their correlation with students' creative thinking abilities.Item Comparison of Acid- and Base-Modified Biochar Derived from Douglas Fir for Removal of Copper (II) from Wastewater(SEPERATIONS:MDPI, 2024-03-01) Beatrice Arwenyo ,; Prashan M. Rodrig; Olalekan A. Olabode; Hashani P. Abeysingh; Jessie N. Tisdal; Rose C. Azuba; Todd E. MlsnaCopper is a non-biodegradable heavy metal, and high levels in water bodies cause serious environmental and health issues. Douglas fir biochar has a higher number of carboxylic, phenolic, and lactonic groups, which provide suitable active sites for copper removal. Douglas fir biochar (BC) was modified using 20% solutions of KOH (KOH/BC), H2SO4, (H2SO4/BC), and Na2CO3 (Na2CO3/BC). All materials were characterized using SEM, SEM-EDS, FTIR, TGA, XRD, BET, and elemental analysis. These modifications were done to compare the activations of those sites by measuring copper removal efficiencies. KOH/BC, H2SO4/BC, and Na2CO3/BC materials gave surface areas of 389.3, 326.7, and 367.9 m2 g−1, respectively, compared with pristine biochar with a surface area of 578.9 m2 g−1. The maximum Langmuir adsorption capacities for Na2CO3/BC, KOH/BC, BC, and H2SO4/BC were 24.79, 18.31, 17.38, and 9.17 mg g−1, respectively. All three modifications gave faster kinetics at 2 mg/L initial copper concentrations (pH 5) compared with pristine BC. The copper removal efficiency was demonstrated in four different spiked real water matrices. The copper removals of all four water matrices were above 90% at 2 mg/L initial concentration with a 2 g/L biochar dosage. The competitive effects of Pb2+, Zn2+, Cd2+, and Mg2+ were studied at equimolar concentrations of Cu2+ and competitive ions for all four materials.Item Sorption of Phosphate on Douglas Fir Biochar Treated with Magnesium Chloride and Potassium Hydroxide for Soil Amendments(MDPI, 2023-09-19) Arwenyo Beatrice 1,2 , Navarathna Chanaka 1 , Krishna Das Naba 1 , Hitt Addie1 and Mlsna Todd1,*With increasing climate variability, a sustainable crop production approach remains an indispensable concern across the globe. In this study, P retention/availability of MgCl2.6H2O/KOH modified Douglas fir biochar was assessed. The MgCl2·6H2O/KOH treated Douglas fir biochar was prepared by sequentially treating Douglas fir biochar with magnesium chloride and potassium hydroxide solutions. The biochar’s surface area, pore volume, morphology, and elemental compositions were determined using BET, SEM, SEM/EDS, and powder X-ray analyzes. Both surface area and pore volume were reduced by more than 97% following modification. Similarly, the morphology and elemental compositions changed after modification. The maximum P adsorbed corresponding to Langmuir–Freundlich model was 41.18 mg g−1. P sorption on biochar soil mixture was pH dependent. More studies are required to establish the field applicability of P-laden MgCl2 ·6H2O/KOH-modified Douglas fir biochar as a soil additive.Item Microplastics and Per- and Polyfluoroalkyl Substances (PFAS) Analysis in Sea Turtles and Bottlenose Dolphins along Mississippi’s Coast(MDPI, Basel, Switzerland., 2023-01-18) Navarathna Chanaka M.; Pray Hannah; M Prashan. Rodrigo; Arwenyo Beatrice; McNeely Cassidy; Reynolds Henry; Hampton Natalie; Lape Katherine; Katie Roman; Heath Maddie; Stokes Sean; R Sameera. Gunatilake; Ariunbold Gombojav; Perez Felio; V. K. G Rooban . Thirumalai; Hassan EI Barbary; Elsayed Islam; Mohan Dinesh; Brown Ashli ,; Moore Debra; Reichley Stephen; Lawrence Mark; MlsnaTodd E.Global plastic production and usage has increased annually for decades and microplastic pollutants ( 5 mm) are a growing concern. Microplastics in surface waters can adsorb and desorb harmful chemicals such as per- and polyfluoroalkyl substances (PFAS). Microplastics can accumulate across all tropic levels in the marine food web. The purpose of this research was to analyze the stomach and intestinal contents of stranded (Mississippi coast) bottlenose dolphins and sea turtles for the presence of microplastics and commonly found PFAS, PFOS, PFOA, and GenX. Gut contents were digested (10% KOH in 50% MeOH) and then analyzed for microplastics using pyrolysis gas chromatography-mass spectrometry (Pyro-GC-MS), Nile red microscopy, X-ray photo electron spectroscopy (XPS), and Raman spectroscopy. Digested sample filtrate was pre-concentrated using solid-phase extraction (SPE) before PFAS liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The PFOS extraction and analysis had 98.6% recovery when validated with certified pike-perch fish reference material. The Nile red testing on most samples revealed the presence of microplastics (Table S1). The Pyro-GC-MS results from two samples confirmed the presence of the plasticizer acetamide. The Raman spectroscopy analysis indicated characteristic plastic peaks corresponding to polystyrene in one sample. PFOS (95.5 to 1,934.5 g/kg) was detected in three dolphin stomach samples. This project is part of a long-term study with the goal of a better understanding of microplastics and PFAS environmental contamination and their impact on bottlenose dolphins and sea turtles.Item PFAS:(Journal of Agricultural Chemistry and Environment,, 2023-08-31) Awolesi Oluwafemi; Oni Peter; Oshinowo Abiodun; Olubusoye Boluwatife; Owusu Faustina; Sunday Simeon Pama; Osobamiro Temitope; Ongwech Acaye; Awolesi Omotoyosi; Arwenyo BeatriceThe C-F bond is one of the strongest in organic chemistry. It is responsible for the great stability of perfluoroalkyl and polyfluoroalkyl substances, commonly referred to as “PFAS”, a group of man-made chemicals that include perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). Thermal stability, surface activity, dielectric characteristics, chemical resistance, and inertness are just a few of the technical advantages that this group has over hydrocarbons, and since the 1950s, these chemicals have been largely utilized in a variety of domestic and industrial endeavors. The hydrophilic and lipophilic nature of this class of chemicals accounts for its uniqueness. Up until today, the chemistry and ecotoxicology of these chemicals continue to emerge. Issues concerning the destructive power of ignorance expedited by an ineffective regulatory institution continue to show that manufacturing chemicals are insufficient without giving serious thought to issues of openness and humanity’s awareness of its own safety. When discussing the nature of humanity and how it can be defined or redefined, it is important to allude to the significance of integrating business with ethics in its various forms. This paper highlights the importance of holding polluters accountable for PFAS contamination cleanup costs while emphasizing the need for chemical manufacturers to test and disclose the health and environmental effects of PFAS compounds. In addition, the sources, types, properties, applications, distribution, toxicological implications, regulations, and analytical methods associated with PFAS (per- and polyfluoroalkyl substances) are explored. The effectiveness of the remedial methods described in this paper needs to be progressively tested while exploring other sustainable approaches.Item Sorption of Phosphate on Douglas Fir Biochar Treated with Magnesium Chloride and Potassium Hydroxide for Soil Amendments(MDPI, Basel, Switzerland., 2023-01-19) Beatrice Arwenyo; Chanaka Navarathna; Naba Krishna Das; Addie Hitt; Todd MlsnaWith increasing climate variability, a sustainable crop production approach remains an indispensable concern across the globe. In this study, P retention/availability of MgCl2.6H2O/KOH modified Douglas fir biochar was assessed. The MgCl2 6H2O/KOH treated Douglas fir biochar was prepared by sequentially treating Douglas fir biochar with magnesium chloride and potassium hydroxide solutions. The biochar’s surface area, pore volume, morphology, and elemental compositions were determined using BET, SEM, SEM/EDS, and powder X-ray analyzes. Both surface area and pore volume were reduced by more than 97% following modification. Similarly, the morphology and elemental compositions changed after modification. The maximum P adsorbed corresponding to Langmuir–Freundlich model was 41.18 mg g1. P sorption on biochar soil mixture was pH dependent. More studies are required to establish the field applicability of P-laden MgCl2 6H2O/KOH-modified Douglas fir biochar as a soil additive.Item Phosphorus enriched modified-Douglas fir biochar as a soil Phosphorus enriched modified-Douglas fir biochar as a soil amendment(Mississippi State University Mississippi State University Scholars Junction, 2022-05-13) Arwenyo, BeatriceBiochar application as a soil additive is gaining global acceptance. In this era of climate change, biochar use for improved soil productivity is not just a sustainable eco-friendly substitute to synthetic fertilizer, but a noble contributor to the fight against climate change. Although biochar has been accredited with some environmental and agricultural benefits, most studies concentrated on agricultural and biowaste products as feedstocks. This research was designed to explore Penriched modified-Douglas fir biochar potential as a soil additive. Using corn as a test crop, greenhouse studies were performed on acidic sandy soil, comparing phosphorus enriched modified-Douglas fir biochar efficacy to a commercial synthetic triple superphosphate fertilizer and a control treatment. Incubation studies were also performed to evaluate the liming and heavy metal immobilization efficacies. Firstly, P-enriched modified-Douglas fir biochar’s ability to release plant soluble P was investigated. At various P enrichment concentration, soil plant availability P from P enriched modified-Douglas fir biochar treatments differed insignificantly from superphosphate fertilizer treatment. The direct correlations between both K and Mg recoveries with available soil P, suggested P enriched modified-Douglas fir biochar potential to supply multiple plant nutrients. Secondly, the influence of P uptake on plant growth and P use efficiency was examined. The greater agronomic P use efficiency obtained in P enriched modified Douglas fir biochar (~32 kg kg-1) than the triple supper phosphate fertilizer (~17 kg kg-1) treatment confirmed P enriched modified-Douglas fir biochar potential as a multiple nutrient released soil additive. Thirdly, biochar-supported phosphate (BP) effectively reduced Pb2+ mobility in simulated contaminated soil. Pb2+reacted with phosphate from Ca10(PO4)6(OH)2 embedded in the biochar supported phosphate at pH<7 forming a less bioavailable Pb10(PO4)6(OH)2. Finally, the amendment of acidic soils with modified P-enriched modified-biochar improved soil buffering capacity because of its enhanced ash contents, alkalinity, and surface functional groups. Spectroscopic methods were used to analyze biochar, soil, and plant materials extracts. Several other analytical methods including BET and thermogravimetric analyses were used to characterized biochar. These findings suggest that the use of phosphorus enriched modified Douglas fir biochar in agricultural soil is a feasible relatively low-cost, effective, and environmentally sustainable soil management and P recycling strategyItem Inorganic nutrients and heavy metals in some wild edible plants consumed by rural communities in Northern Uganda:(Elsevier Ltd., 2023-08-04) Alfred Nyeroa; Innocent Achayea; Godwin Upoki Anywarc; Geoffrey Maxwell MalingabFor centuries, wild edible plant species have sustained local communities across Africa by supplementing households’ diets in seasons of food shortage. Wild edible plants contain inorganic nutrients, which are essential for the proper functioning of organisms. However, their nutritional contents have not been well researched and are generally poorly understood. This study aimed to quantify the levels of inorganic micro-and macronutrients as well as heavy metals (Mg, Ca, K, Fe, Zn, Cd, Hg and Pb) in selected wild edible plants traditionally consumed among the Acholi communities in northern Uganda, and associated health risks of consuming them. The leaves and young stems of 12 wild edible plants, viz: Acalypha rhomboidea, Asystacia gangetica, Crassocephalum sacrobasis, Crotalaria ochroleuca, Heterotis rotundifolia, Hibiscus cannabinus, Hibiscus sp., Hibiscus surattensis, Ipomoea eriocarpa, Maerua angolensis, Senna obtusifolia and Vigna membranacea were air-dried and crushed to powder. The powders were then macerated using aqua regia solution and analyzed in triplicates using the Atomic Absorption Spectrophotometry (AAS). The target hazard quotient (THQ) of Pb was calculated for non-carcinogenic health risks. Mg, Ca, K, Fe, Zn and Pb were detectable in all the wild edible plants sampled. All inorganic nutrients (mg/ 100gdw), were below the Recommended Daily Allowance (RDA); Mg (9.4 ± 0.19 to 10.4 ± 0.15), Ca (119 ± 5.82 to 1265 ± 14.9), Fe (3.29 ± 0.02 to 11.2 ± 0.09), Zn (0.52 ± 0.02 to 2.36 ± 0.03). Hg and Cd were below detectable limits in all the samples tested. The content of Pb (0.69 ± 0.11 to1.22 ± 0.07) was higher than the CODEX and EU limits of 0.1 ppm (0.001 mg/g) but was below the recommended threshold of 1. The health risk assessment revealed no potential hazards both in children and adults. However, there is a need to study the bioavailability of Pb when the vegetables are consumed due to factors such as indigestion and antinutritional compoundsItem Contribution of modified P-enriched biochar on pH buffering capacity of acidic soil(Elsevier Journal of Environmental Management, 2022-11-06) Arwenyo, Beatrice; Varco, Jac J.; Dygert, Andrew; Brown, Sydney; Pittman, Charles U.; Mlsna, ToddBiochar can directly hold cations in soil because of the negative charge that exists on its surfaces. Besides, improving soil cation exchange capacity, the negative charges on biochar surfaces can buffer acid soil by pro tonation and deprotonation mechanisms. Moreover, biochar ameliorates soil acidity due to the presence of ox ides, carbonates, and hydroxides of its basic cations (Ca, Na, K, and Mg). Both biochar surface functional group and basic cation concentrations can be altered by modification with chemical agents which can affect its soil pH buffering capacity. However, the impact of modified biochar application on soil pH buffering capacity is still scanty. This study investigated the pH buffering capacity of acidic soil amended with three P-enriched modified Douglas fir biochars and compared this buffering capacity to amendment with untreated Douglas fir biochar. These three P-enriched biochars, were prepared by treating Douglas fir biochar (DFB), respectively, with: 1) anhydrous calcium chloride (CaCl2) and potassium phosphate monobasic (KH2PO4), 2) calcium carbonate (CaCO3) and diammonium phosphate {(NH4)2HPO4} and 3) an aqueous solution of magnesium sulfate (MgSO4), potassium hydroxide (KOH) and potassium phosphate monobasic (KH2PO4). The three P-enriched biochars were designated as CCPP, CAPP and MSPP, respectively. The soil pH buffering abilities were largely dependent on the added biochar’s alkalinity and ash contents. The residual soil CEC was highly correlated (r ≥ 0.9), with the soil buffering capacity. Both alkalinity and pH buffering capacity improved following the order CCAP > CCPP > MSPP > DFB, while residual soil CEC followed the order CAPP > MSPP > CCPP > DFB. The pH buffering ca pacity of the soil after amendments with 10% CAPP, CCPP MSPP and BFB rose by 84.8, 58.3, 3.0 and 2.5%, respectively. Whereas MSPP had higher concentrations of K+ and Mg2+, greater concentrations of Ca2+ were present in CCAP and CCPP than MSPP. So, Ca2+ concentrations in biochar exerts a greater influence on alkalinity and buffering capacity than Mg2+ and K+ because of 1) its smaller effective hydration radius and larger charge density. 2) calcium hydroxide has a greater water solubility than magnesium hydroxide providing more available base. Since pH buffering capacity depends on cation exchange sites, soil additives containing Ca2+ are prone to create greater impacts than Mg2+ and K+ additives.