Browsing by Author "Ssebugere, Patrick"

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Environmental levels and human body burdens of per- and poly-fluoroalkyl substances in Africa: a critical review
(Elsevier : Science of The Total Environment., 2020-10-15) Ssebugere, Patrick; Sillanpää, Mika; Matovu, Henry; Wang, Zhanyun; Schramm, Karl-Werner; Omwoma, Solomon; Wanasolo, William; ChelangatNgeno, Emily; Odongo, Silver
Per- and polyfluoroalkyl substances (PFASs) are known organic pollutants with adverse health effects on humans and the ecosystem. This paper synthesises literature about the status of the pollutants and their precursors, identifies knowledge gaps and discusses future perspectives on the study of PFASs in Africa. Limited data on PFASs prevalence in Africa is available because there is limited capacity to monitor PFASs in African laboratories. The levels of PFASs in Africa are higher in samples from urban and industrialized areas compared to rural areas. Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are the dominant PFASs in human samples from Africa. Levels of PFOS and PFOA in these samples are lower than or comparable to those from industrialized countries. PFOA and PFOS levels in drinking water in Africa are, in some cases, higher than the EPA drinking water guidelines suggesting potential risk to humans. The levels of PFASs in birds' eggs from South Africa are higher, while those in other environmental media from Africa are lower or comparable to those from industrialized countries. Diet influences the pollutant levels in fish, while size and sex affect their accumulation in crocodiles. No bioaccumulation of PFASs in aquatic systems in Africa could be confirmed due to small sample sizes. Reported sources of PFASs in Africa include municipal landfills, inefficient wastewater treatment plants, consumer products containing PFASs, industrial wastewater and urban runoff. Relevant stakeholders need to take serious action to identify and deal with the salient sources of PFASs on the African continent.
Not one size fits all: µ FTIR and pyrolysis GC MS for complementary analysis of microplastics in eutrophic surface water
(Analytical and Bioanalytical Chemistry, 2026-03-22) Omara, Timothy; Benetková, Barbora; Sumerskii, Ivan; Ssebugere, Patrick; Kyarimpa, Christine; Omwoma, Lugasi Solomon; Rosenau, Thomas; Nagawa, Christine Betty; Böhmdorfer, Stefan
This study reports large microplastics found in Lake Victoria through an analytical workflow that combines the complementary methods stereomicroscopy, micro-Fourier transform infrared (µ-FTIR) spectroscopy and pyrolysis gas chromatography-mass spectrometry (Pyr-GC-MS) for the quantification of 11 environmentally relevant microplastic polymers. Algae-rich surface water samples (n = 18) were trawled using a 0.3 mm manta net from Lake Victoria, the world’s largest tropical lake. Stereomicroscopy as a determinant analytical technique detected 191 particles, which were primarily blue fragments and fibres. Polyethylene and polypropylene were the dominant polymers identified by µ-FTIR. Pyr-GC-MS allowed the detection and quantification of microplastics (MPs) with LOD and LOQ of 0.01–14.7 µg and 0.03–49.1 µg. Polyethylene (0.058–0.34 µg/L), polypropylene (0.024 µg/L and 0.043 µg/L), nylon 6 (0.0051–0.064 µg/L), nylon 66 (0.0022–0.084 µg/L), poly(ethylene terephthalate) (0.0029–0.027 µg/L) and poly(methyl methacrylate) (0.0036 µg/L) were quantified. µ-FTIR was found to be suitable for the identification of the most abundant polymers in the 0.3–4.9 mm size range whereas Pyr-GC-MS afforded the quantification of seven polymers, most of which were not detected by µ-FTIR. This complementary workflow gave a wider perspective on MP loading, providing both polymer concentrations and physical characteristics (sizes, colours, forms and count) of the MPs.
Occurrence of microplastics in surface water, superficial sediments and Nile tilapia (Oreochromis niloticus) from fish breeding areas of Lake Victoria
(Discover Applied Sciences, 2026-03-27) Atukwatse, Faith; Nagawa, Christine Betty; Omara, Timothy; Kyarimpa, Christine; Omwoma, Solomon Lugasi; Basooma, Rose; Kwikiriza, Gerald; Ssebugere, Patrick; Bwanika, Gladys Namuswe
Lake Victoria, the largest African Great Lake and the world’s second largest freshwater lake by surface area has several bays and inlets along its shoreline, which serve as breeding grounds for fish. The ecological and economic importance of these bays are now under threat due to rapid urbanization and agricultural expansion that have introduced pollutants into them. Using stereomicroscopy and micro-Fourier transform infrared (µ-FTIR) imaging, we investigated the occurrence of microplastics (MPs) in surface water (n = 12), superficial sediments (n = 12) and Nile tilapia (Oreochromis niloticus, n = 66) from four fish breeding areas (Port Bell, Masese, Kigaya and Nabulugo) on the northern shores of Lake Victoria. The frequency of MPs detection was 100%, 83.3% and 56.1% in surface water, sediments and fish samples, respectively. The corresponding microplastic counts were 22–60 particles/L, 2–10 items/kg and 1–16 items/fish. Port Bell and Masese that are in close proximity to urban areas had higher microplastic contamination than Kigaya and Nabulugo, which are in less disturbed sites (P > 0.05). Across all the samples, filaments were the most dominant form of MPs (43.1–100%), followed by fragments (7.8–55.6%), fibers (2.2–21.4%), foams (5.3–31.1%) and pellets (1.7–6.7%). The particles were confirmed by µ-FTIR to contain mainly polyethylene, polypropylene and polystyrene. Total length of fish from Nabulugo showed a strong and significant negative correlation (ρ = – 0.753, P = 0.01) with the number of MPs ingested, indicating that larger fish are associated with lower microplastic loads. Branchial intrusion of MPs in Oreochromis niloticus provide evidence of potential direct human exposure to MPs through consumption of this fish species. These results indicate that there is a growing threat of MPs to fishery sustainability and food safety in Lake Victoria, emphasizing the need for targeted policy interventions to mitigate plastic pollution in catchments of fish breeding habitats.
Refined analysis of microplastics in endemic fish species from Lake Victoria using µ-FTIR and pyrolysis GC-MS
(Environmental Monitoring and Assessment, 2026-08-14) Omara, Timothy; Benetková, Barbora; Sumerskii, Ivan; Ssebugere, Patrick; Kyarimpa, Christine; Omwoma, Solomon Lugasi; Rosenau, Thomas; Nagawa, Christine Betty; Böhmdorfer, Stefan
Pyrolysis–gas chromatography–mass spectrometry (Pyr-GC-MS) has evolved into one of the most powerful methods for microplastics (MPs) analysis. However, analytical challenges are still encountered whenever Pyr-GC-MS is applied to matrices with high organic matter, protein and lipid contents. In this study, a workflow integrating stereomicroscopy, micro-Fourier transform infrared (µ-FTIR) spectroscopy and Pyr-GC-MS was extended to analyse MPs in three endemic fish species (Protopterus aethiopicus, Rastrineobola argentea and Synodontis victoriae) from Lake Victoria. Stereomicroscopic analysis only detected MPs in the gastrointestinal tracts of P. aethiopicus and S. victoriae, with the highest mean particle numbers being 16.0 ± 7.8 and 14.7 ± 6.7 items/fish taxon, respectively. No MPs were found in whole samples of R. argentea. The microparticles were mostly blue and brown 0.3–1.9-mm fragments and filaments, which µ-FTIR analysis confirmed to be composed of nylon 66, nylon 6/66, nylon 6/10, nylon 11, polyethylene and polypropylene. Retention time locking and post-column backflush considerably reduced the cycle time and increased stability of the Pyr-GC-MS method. Nylon 66 (243 µg/g in S. victoriae), nylon 6 (0.24–96 µg/g), polypropylene (6.4 µg/g in P. aethiopicus), poly(ethylene terephthalate) (1.2–107 µg/g) and styrene-butadiene rubber (8.5–34.8 µg/g) were quantified. Polyethylene and poly(methyl methacrylate) were detected below their limits of quantification. To prevent false positive detection of polyethylene in the lipid-rich tissues, the evaluation focussed on C21-α,ω-alkene as a marker. Polypropylene was not detected in some samples, as it formed several discrete propylene oligomers during pyrolysis, which suppressed the yield of its target quantification marker (2,4-dimethyl-1-heptene).