We investigated the occurrence, species-specific distribution, accumulation, and biomagnification of poly- and perfluoroalkyl substances (PFAS) in three teleost fish species (Sarotherodon melanotheron, Clarias gariepinus, and Chrysicthys nigrodigitatus), as well as molluscs (Pachymelania aurita), earthworms (Lumbricus terrestris), and sediment samples from the Ologe Lagoon in Nigeria, which receives complex mixtures of anthropogenic effluents from various sources. Total ∑PFAS concentrations (ng/g) were significantly highest in earthworms (16.2), compared to teleost species (S. melanotheron (1.8), C. gariepinus (1.2), and C. nigrodigitatus (1.8)) and molluscs (0.4). The novel precursor diSAMPAP was the dominant PFAS congener in S. melanotheron and C. gariepinus, while PFOS and diSAMPAP were highest in C. nigrodigitatus. In earthworms, molluscs, and sediment, diSAMPAP, PFBS, and PFOS were the dominant PFAS. We calculated the biota sediment accumulation factor (BSAF), revealing that diSAMPAP in S. melanotheron and 8:2 FTS in earthworms exhibited the highest BSAF values. Species-specific differences in PFAS biomagnification factor (BMF) suggest varying exposure routes among the examined fish species. Notably, PFOS concentrations in the liver were significantly higher than in flesh tissues for C. gariepinus and C. nigrodigitatus, indicating organ-specific accumulation. Risk analysis using the Risk21 tool showed that S. melanotheron had the highest public health risk, while C. gariepinus had the least risk. Our results highlight significant food safety concerns and public health risks associated with the occurrence, species-specific distribution, accumulation, and biomagnification of diSAMPAP, 8:2 FTS, and PFOS in the Ologe Lagoon and its aquatic food webs. This study contributes valuable insights to global PFAS monitoring efforts, particularly in fluvial tropical ecosystems such as those found in Nigeria.

Pollution, urbanization and technological advancements have posed stress on the ecosystem and its matrices. Globally, pollutants are observed in all compartments of ecological communities which affect the integrity of the atmosphere, hydrosphere, lithosphere and biosphere. Xenobiotics bioaccumulate and biomagnify across trophic levels or webs. Heavy metals have been implicated in impacts towards biodiversity and environmental declination. In Nigeria, wastes issues are a cause of concern and landfilling or are waste disposal approaches that cause deleterious effects such as depauperation of diversity and species decline, prompting the non-invasive ecotoxicological hazard assessments. Feathers were used to assess concentration levels of 13 metals (Fe, Mn, Zn, Cu, Co, Cr, Cd, Pb, Ni, Al, B, Se and Hg) using fast atomic absorption spectrophotometer (FAAS), one-way ANOVA was used in comparing variations in mean concentrations across trophic levels, diversity indices and point count methods were used to estimate diversity and abundance. Four avian species were assessed Hirundo aethiopica (insectivore), Streptoptelia senegalensis (granivore), Turdus pelios (omnivore), and Anthus leucophrys. (insectivore). Observed concentrations of important metals like iron were high with the insectivores having the highest concentrations of iron (2.6985 ± 0.1975 ppm) and granivores having the lowest (2.0100 ± 0.3172 ppm). The insectivores had the highest concentrations for cadmium, cobalt and chromium (0.0005 ± 0.0005ppm), nickel (at 00.0012 ± 0.0017 ppm) and least was observed in the granivores (0.0003 ± 0.0006 ppm). Selenium concentrations were quite high in insectivores (0.0775 ± 0.0035 ppm) and lowest in granivores (0.0433 ± 0.0015 ppm) likewise mercury for insectivores (0.0280 ± 0.0010 ppm) and granivores (0.0213 ± 0.0015 ppm). From the study, it is apparent that landfills are sources of pollution and poor management of wastes can affect biota (causing effects such as asymmetry and bioaccumulation) and ecosystem balance. The observation of heavy metals in the feathers serve as good sentinels due to their trophic levels and could be signs for what could be yet to occur. The heavy metal concentrations were significantly different at p < 0.05.

Microplastic pollution presents a serious risk to marine ecosystems worldwide, with West Africa being especially susceptible. This study sought to identify the key factors driving microplastic dynamics in the region. Using NASA's Giovanni system, we analyzed environmental data from 2019 to 2024. Results showed uniform offshore air temperatures due to turbulence (25.22-45.62 K) with significant variations nearshore. Salinity levels remained largely stable (4 PSU) but slightly decreased in southern Nigeria. Surface wind speeds rose from 4.206-5.026 m/s in Nigeria to over 5.848 m/s off Mauritania, while eastward stress hotspots were prominent in Nigeria and from Sierra Leone to Senegal. Photosynthetically available radiation (PAR) beam values peaked off Mauritania and dipped from Nigeria to Sierra Leone, with the inverse pattern observed for diffuse PAR. Hotspots of high absorption, particulate backscattering, elevated aerosol optical depth, and remote sensing reflectance all pointed to substantial particulate matter concentrations. The Microplastic Vulnerability Index (MVI) identifies the coastal stretch from Nigeria to Guinea-Bissau as highly vulnerable to microplastic accumulation due to conditions that favor buildup. In contrast, moderate vulnerability was observed from Guinea-Bissau to Senegal and in Mauritania, where conditions were less extreme, such as higher offshore temperatures that could promote widespread microplastic suspension and cooler nearshore temperatures that favor sedimentation. Increased turbulence and temperatures in coastal areas of Senegal and Mauritania may enhance microplastic transport and impact marine life. In Nigeria, stable coastal conditions-characterized by consistent temperatures, low turbulence, and uniform salinity-may lead to increased persistence and accumulation of microplastics in sensitive habitats like mangroves and coral reefs. These findings highlight the need for region-specific management strategies to address microplastic pollution and effectively protect marine ecosystems.

Wetland diversity metrics are critical indicators of habitat carrying capacity and anthropogenic disturbance on ecosystem health. This study aimed at comparing the composition and ecological features of bird communities across gradients of habitat effects within wetland areas of freshwater tropical lakes. For this study, the total number, diversity, and dominance of bird communities (n = 519; 29 species) within a 1 km radius riparian area of four tropical lakes were measured and compared alongside habitat effect variables. Three categories of habitat effect variables i.e., lake morphology (surface area of lake, lake perimeter, shape index i.e., form factor); landscape structure (vegetation density within 1 km radius measured using Normalized Difference Vegetation Index [NDVI]), and human disturbance/urbanization features (distance to major road, distance to residential area) were assessed across the four lake wetlands. The multivariate relationship of variables was described using non-metric multidimentional scaling (NMDS) of six habitat effect variables alongside Hill numbers diversity as dependent variables showed that variation in bird species composition was strongly negatively correlated with lake shape index, and positively correlated with vegetation density (NDVI) and distance to the road (indicating complementary effects). This implies that wetlands with heterogeneously shaped lakes alongside greater vegetation density (NDVI), and increased furtherance from major highways (urbanization features) were more likely to attract and accommodate more diverse bird communities. Furthermore, the habitat-specific avian guild structure highlighted the carrying capacity of the different lake wetlands. The study findings imply that the conservation of wetland avifauna will require emphasis on habitat-specific variables.

The global trade in used vehicles and their components generates huge financial benefits but leads to detrimental environmental consequences including groundwater pollution and potential adverse health effects mediated by free-radical processes such as lipid peroxidation. We investigated oxidative stress responses in thirty-six, female mice orally exposed (via drinking) to graded concentrations (0%, 50%, and 100%) of groundwater from a well located within a major automobile junk market in SW-Nigeria containing extremely high levels of arsenic (0.332 ± 0.089 mg/l) and seventeen PAHs, which serves as domestic water supply. Blood samples from the mice were assayed for selected biochemical parameters at intervals of 7, 14, and 28 days. A significant dose- and duration-dependent increase in malondialdehyde (MDA) and Myeloperoxidase (MPO) confirmed oxidative stress onset due to exposure to the polluted well-water, while a significant decline in nitric oxide (NO−) levels may suggest impaired endothelial smooth-muscle relaxation which may lead to the development of metabolic diseases over time. Superoxide dismutase (SOD) and reduced glutathione (GSH) showed a contrasting trend with Glutathione peroxidase (GPx), while Glutathione-S-Transferase (GST) declined significantly by the 28th day. Two clusters were identified by principal component analysis—one involving MDA, SOD, and GSH suggesting that antioxidant responses driven mainly by SOD and GSH proved insufficient in scavenging the free radicals generated by lipid peroxidation. NO− and total protein clustered together possibly due to the significant declines in both over the study period. Histological examination of liver tissue of exposed mice corroborated the above findings and highlights the need for urgent remedial action.

Spent engine oil (SEO) contains toxic metals which may be leached into water supplies during precipitation. These metals may bioaccumulate during exposure, eliciting adverse effects on the liver and the kidneys, both target organs for several contaminants. This study determined the hepatotoxic and renal effects of the water soluble fractions (WSF) of SEO in mice. The levels of renal function biomarkers (creatinine and urea) and iron, zinc, copper, nickel, lead and cadmium levels in livers of twenty-four male albino mice administered daily oral gavages of 0%, 1%, 10% and 100% WSF of SEO for 30 days were evaluated. Creatinine (0.17±0.06 mg/dl) and urea (22.33±1.53 mg/dl) levels were lowest and highest respectively at 10%, although values were marginal but were not significantly different from control (p>0.05). Iron (61150.27±2300.25ug/l), Zn (25942.57±975.86), Cu (7412.20±278.81), and Ni (185.33±6.98ug/l) levels in the liver were significantly elevated (p 0.05) compared with control and other treatments. Iron, zinc, copper and nickel levels at 10% were highest in the treatments. These results provide evidence for the adverse renal and hepatotoxic effects of water contaminated with SEO and highlight the need for its proper management. Keywords : Hepatotoxicity, creatinine, urea, metal contaminants, waste oil.

Contamination of soil and underlying groundwater with spent engine oil from automobile workshops and garages has serious ecological problems affecting plants and animals. The spermatotoxic potential of spent engine oil (SEO) was investigated using 24 adult male Swiss albino mice having mean weight of 24.67±0.2 g for 30 days. The mice were divided into 4 groups A, B, C, D of six mice each. Group A (control) was treated orally with distilled water, B (100% water soluble fractions (WSF) of spent engine oil), C (10% water soluble fractions (WSF) of spent engine oil) and D (1% water soluble fractions (WSF) of spent engine oil). It was observed that the mean percentage sperm motility, viability and sperm count of the treated groups B, C, and D decreased compared to the control, although the differences were not significant (p>0.05). This same trend was observed for the morphologically abnormal sperm cells of mice in the treated groups compared to the control. It was concluded in this study that treatment with water soluble fractions of spent engine oil for 30 days had no negative effect on the semen characteristics and testicular biometry of Swiss albino mice.© 2016 International Formulae Group. All rights reservedKeywords: Mice, semen, spent engine oil, testes

Aims: We report a pilot study evaluating the antitumor properties of a Schiff base ligand, 3-[2,4-dihydro-1H-inden-4-y1 imino)methyl] napthalen-2-ol] and aqueous herbal extract against N-methylN-Nitrosourea (MNU)-induced carcinomas in albino mice via hematology; and histology of the liver, thymus, spleen and small intestine.Study Design: Twenty-three male and female mice respectively received a single intra-peritoneal dose of 60 mg/kg MNU. Seven males and seven females served as controls.Place and Duration of Study: Department of Zoology, University of Ibadan, Ibadan, Nigeria; January-July 2012.Methodology: Five months post-induction, four induced males and four females of surviving mice were given a single intra-peritoneal dose (25 mg/kg) of ligand; three induced males and three females served as negative control. Three induced mice of both sexes respectively received daily doses of 136 mg/mL extract orally at an innoculation volume of 0.3 mL/mouse for 30 days (total dosage= 4.08 g/30 ml;) and monitored for two months. Depending on mortality, 1-3 mice/group were sacrificed at experiment termination and subsequently processed for hematology and histology.Results: Tumor incidence was 13% (male) and 17% (female) respectively. There was no significant difference (P=.05) between hematology of control and statistically comparable experimental groups. Histology of control organs showed no abnormal features. Hepatocytes of ligand-treated mice showed cytoplasmic disintegration and presence of pleomorphic nuclei; while the extract treated group showed progressive reversal towards normal with hepatocytic regeneration, fairly uniformly-shaped nuclei and bi-nucleate cells. Spleen of the ligand-treated group showed moderate lymphoid depletion, while the extract-treated group showed a regeneration of the central artery and red pulp with no visible lesion. The extract-treated thymus showed a gradual reversal of some of its Hassall's corpuscles. The small intestine of the ligand-treated mice showed gross erosion of the intestinal villi; while intestinal mucosa regeneration was observed in the extract-treated group.Conclusion: The herbal extract may possess some antitumor properties, thus necessitating further investigations, while the ligand showed little or no activity in vivo.

Contamination of soil and underlying groundwater wit h spent engine oil from automobile workshops and garages has serious ecological problems affecti ng plants and animals. The spermatotoxic potential of spent engine oil (SEO) was investigated using 24 adult ma le Swiss albino mice having mean weight of 24.67±0. 2 g for 30 days. The mice were divided into 4 groups A, B, C, D of six mice each. Group A (control) was trea ted orally with distilled water, B (100% water soluble f ractions (WSF) of spent engine oil), C (10% water so luble fractions (WSF) of spent engine oil) and D (1% wate r soluble fractions (WSF) of spent engine oil). It was observed that the mean percentage sperm motility, v iability and sperm count of the treated groups B, C, and D decreased compared to the control, although the dif f rences were not significant (p>0.05). This same t rend was observed for the morphologically abnormal sperm cel ls of mice in the treated groups compared to the co ntrol. It was concluded in this study that treatment with water soluble fractions of spent engine oil for 30 days had no negative effect on the semen characteristics and te sticular biometry of Swiss albino mice. © 2016 International Formulae Group. All rights res erved

Aims: This study evaluated the impact of metal and metal containing wastes (plastics, glass, miscellaneous and fines) on cadmium and lead contents in soil and leachate and the inter-relationships among the various waste categories dumped on the site, using Principal Component Analysis (PCA). Study Design: Cadmium and lead contents in top soils of Sub-site WDA (Waste Dump Area) and LLA (Leachate Lagoon Area) (wdatscd, wdatspb; llatscd, llatspb); at 15-30cm depth i.e. sub-soil 1 (wdass1cd, wdass1pb; llass1cd, llass1pb); at 31-60cm depth i.e. sub soil 2 (wdass2cd, wdass2pb) and attenuated leachate cadmium and lead (alcd, alpb) were used along with the various waste fractions for PCA analysis. Place and Duration of Study: Department of Zoology, University of Ibadan, Ibadan, Nigeria. January 2003-September 2004; Institute of Applied Ecology, Shenyang, China. May 2006-May 2007. Methodology: Solid waste, leachate and soil were collected from two sub-sites (WDA and LLA and comparative control 600m away) from the Aba-Eku landfill site, Ibadan, Nigeria in February, April, August, October and December 2003; as well as in June 2004. Original Research Article Article British Journal of Applied Science & Technology, 4(11): 1693-1717, 2014 1694 They were analyzed for cadmium and lead contents using Inductively Coupled Plasma Spectroscopy after Hydrofluoric-Perchloric-Nitric acid digestion. Data obtained were subjected to PCA analysis. Results: The tendency of the various metal containing waste categories to cluster with lead and cadmium in leachate and soil on more than one principal component is suggestive of the degree of input to lead and cadmium contamination in soil and leachate. Metals contributed the highest (cluster on all three PCs) followed by plastics and the miscellaneous fraction (cluster on two PCs), glass and the fines fraction (cluster on one PC). Results also revealed two main clusters of biodegradable (Food wastes, miscellaneous and fines or soil) and non-biodegradable wastes (Glass/ceramics and metals). Conclusion: Based on these results, increased recovery and recycling of the metal, plastics and glass/ceramics waste fractions in particular, are suggested.

Aims: Bioassays measure environmentally relevant toxicity.Consequently, increasing attention has focused on incorporating toxicity tests in hazard evaluations of contaminated sites.We evaluated the lethal and sub-lethal effects of contaminated dumpsite soils at various depths using the earthworm Eisenia fetida.Study Design: Four contaminated dumpsite soils WDA [Waste Dump Area] 1 & 2 representing top soils (0-15cm depth), WDA 3 (15-30cm depth) WDA 4 (75-100cm depth) and field control (CS-control soil) were inoculated with E. fetida (12 worms/500g soil).Place and Duration of Study:

Groundwater contamination by landfill leachate is a recognized socio-economic and environmental problem in many countries. The Aba-Eku dumpsite was upgraded and the present study undertaken to characterize groundwater quality in the vicinity of the site to assess the effectiveness of the upgrades. Twenty three parameters were assessed in two groundwater wells (GW1 and GW2 located 600m from the site) over a twenty-month period using Inductively Coupled Plasma Spectroscopy and Ion Chromatography. Data were analyzed using t-test, ANOVA and correlation coefficients. Phosphates and nitrites were below detection limits. Suspended solids: [42.96±67.68 mg/l]; COD-[9.80±4.07mg/l]; and four metals [Pb: 0.047±0.029; Cu: 0.017±0.009; Ni: 0.012±0.011; Cr: 0.014±0.019 mg/l] were elevated in the up-gradient well GW1. However, only lead was significant (p<0.05). Fifteen parameters were elevated in GW2 down-gradient, of which nine including: pH: 8.15±0.11, dissolved solids: 241.39±62.89; magnesium: 28.25±17.52; chloride: 38.19±16.80; sulphate: 27.00±9.62 and cadmium: 0.070±0.045 mg/l were significant (p<0.05). Mean lead, GW1-0.047±0.029; GW2- 0.015±0.018; cadmium GW1-0.028±0.047; GW2-0.070±0.045 and iron GW1-0.82±0.61; GW2- 2.43±4.33 mg/l levels in both wells exceeded regulatory limits. Correlation results [GW1:TSSCOD; 0.713;p<0.01; GW2:TSS-COD:0.262] indicated that the turbid nature of GW1 reflected in higher levels of TSS appeared to be composed of organics and may have contributed to lead mobilization in this well. Zinc mobilization in both wells was strongly pH dependent [GW1: pH-Zn: -0.491;p<0.01; GW2:pH-Zn: -0.682;p<0.05]. Seasonal variations were less distinct. However, increased leachate influx into GW2 resulted in significantly elevated wet season levels of pH, nitrates, sulphates, chloride and TDS. There is urgent need for remediation in view of the health implications of these pollutants.Key words: Groundwater, Aba-Eku dumpsite, landfill leachate, Remediation.

El tratamiento de lixiviados debe ser adecuado para disminuir el impacto ambiental. En la localidad de Aba-Eku, Ibadan al suroeste de Nigeria, se encuentra una laguna de lixiviados donde se efectúa un tratamiento correcto. Durante enero del 2003 y setiembre del 2004 se tomaron muestras comparativas mensuales a la laguna y a las aguas subterráneas de: pH, TSS, solidos totales, conductividad y DQO. Se analizaron con métodos del Departamento de Salud Pública de los Estados Unidos. El calcio y el magnesio se determinaron por medio del plasma de acoplamiento inductivo, aniones seleccionados y el amoníaco por cromatografía iónica. Los coeficientes de prueba T y la correlación se utilizaron para el análisis de datos. Los resultados fueron los siguientes: pH: 8,21, SST: 144,94mg/l, sólidos totales: 1377,67mg/l, conductividad: 2466,00 us/cm y COD: 57,63mg/l fueron significativamente elevados (p

The rates of photodegradation and photocatalysis of benzo[a]pyrene (BaP) on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible for photodegradation, catalyst loads and wavelength of UV irradiation blamed for photocatalysis have been monitored. The results obtained indicated that BaP photodegradation follows pseudo-first-order kinetics. BaP photodegradation was the fastest at 30°C. The rates of BaP photodegradation at different soil particle size followed the order: less than 1 mm>less than 0.45 mm>less than 0.25 mm. When the soil depth increased from 1 mm to 4 mm, the half-life increased from 13.23 d to 17.73 d. The additions of TiO2 or Fe2O3 accelerated the photodegradation of BaP, and the photocatalysis of BaP follows pseudo-first-order kinetics. Changes in catalyst loads of TiO2 (0.5%, 1%, 2%, and 3% (wt)) or Fe2O3 (2%, 5%, 7%, and 10% (wt)) did not significantly affect the degradation rates. Both BaP photocatalysis in the presence of TiO2 and Fe2O3 were the fastest at 254 nm UV irradiation.