DEPARTMENT OF ENVIRONMENTAL MANAGEMENT AND TOXICOLOGY

Climate change is a global problem exacerbated by human actions and behaviour. For this reason, it has become essential for individuals to take actions at their level to decrease their environmental footprint and mitigate climate change. This study was carried out to determine the efforts made by individuals residing in Benin City towards climate change mitigation. There were a total of 100 participants in the study who were selected using convenience sampling. Data was collected using a structured questionnaire having a reliability index of 0.819. Collected data was analysed using descriptive and inferential statistical tools in SPSS version 20. The results obtained showed that the participants were mostly female (65%) and aged between 18 - 25 years (76.3%). The awareness on climate change among participants was moderate. However, knowledge on climate mitigation actions was low and implementation of mitigation actions was minimal. The efforts made by individuals were found to have a positive impact on environmental sustainability in their surroundings. The awareness of climate change and mitigation efforts were significantly positively correlated (R = 0.550, p =0.000), similarly the awareness of climate change and efforts towards environmental sustainability were significantly correlated (R = 0.522, p =0.000). Therefore, it was concluded that based on the findings, targeted interventions are necessary to increased knowledge on climate change, mitigation measures and the implementation of climate mitigation plans to ensure environmental sustainability

This study assessed the physiochemical and heavy metal properties of gully erosion site in Evbhomore Community, Benin City, Edo State. Water and soil samples were collected into sterile plastic container to avoid additional contamination before taken to the laboratory for physicochemical and heavy metal analysis following standard procedures. Physicochemical characteristics of soils samples showed that clay ranged from 24.00 ± 1.92 - 36.00 ± 2.96 %, silt (24.00 ± 1.92 - 33.00 ± 2.83 %), sand (33.00 ± 2.83 - 51.00 ± 3.89 %). pH ranged from 6.70 ± 0.50 - 7.88 ± 0.93, organic matter (0.91 ± 0.37 - 2.00 ± 1.00 %), organic carbon (0.51 ± 0.25 - 0.89 ± 0.37 %) and total nitrogen (0.01 ± 0.00 - 0.05 ± 0.00 %). Electrical conductivity ranged from 4.12 ± 1.45 - 4.81 ± 0.36 µS/cm, available phosphorus (150.00 ± 5.00 - 180.00 ± 5.74 mg/kg) and total exchangeable bases (1.60 ± 0.42 - 1.99 ± 0.69 cmol/kg). In soil samples, cadmium values ranged from 0.16±0.13 - 0.30±0.13mg/kg, Lead (1.26 ± 0.33 - 3.50 ± 0.51mg/kg), Zinc (25.12 ± 2.82 - 79.02 ± 3.29 mg/kg), Copper (27.89 ± 2.49 - 63.08 ± 3.68 mg/kg), Iron (191.16 ± 5.07 - 212.16 ± 5.92 mg/kg) and Manganese (10.80 ± 0.49 - 18.00 ± 0.81 mg/kg). Soil and land cover contributed 12% and 6% respectively to gully erosion in the study area. The occurrence of soil erosion risk in the study area has also been on the increase and is not limited to a particular area but all part causing serious land degradation affecting a wide variety of soils prone to crusting and/or piping. The widths and depths of gully erosion increased with the increase in slope gradient and decrease with increase in percentage of vegetation cover, especially during the rainy season and confirm that soil erosion in the study area has altered vegetation cover, ground slope, slope length and shape. There is therefore the need for protective strategies and measures for sensitive management of the environment to reduce erosion rates and increasing water conservation

Land use and land cover changes within tertiary educational institutions significantly impact environmental sustainability, biodiversity, and ecological health. This study examined spatiotemporal variations in land use/land cover (LULC) and vegetation dynamics of the University of Benin, Ekehuan Campus, Benin City, Edo State, Nigeria, over a 50-year period from 1975 to 2025. Landsat satellite imagery from the years 1975, 1985, 1995, 2005, 2015, and 2025 respectively was processed using Google Earth Engine (GEE) and ArcGIS platforms, with classifications categorized into dense vegetation, sparse vegetation, agricultural land, built-up areas, and bare soil. Supervised Maximum Likelihood Classification was employed for LULC analysis, while the Normalized Difference Vegetation Index (NDVI) was computed to assess vegetation health. Field surveys documented remaining tree species in the study area. Results revealed catastrophic vegetation decline from 0.841334 km² (97.34%) in 1975 to complete elimination (0%) by 2015-2025. Built-up areas increased dramatically from 0% in 1975 to 0.671581 km² (77.70%) by 2025. Agricultural land fluctuated from 0% to 36.49% (2015) before declining to 16.06% in 2025. Bare soil emerged at 6.24% in 2025, indicating land degradation. NDVI values ranged from - 0.077 to 0.400 across the study period, with maximum values declining from 0.400507 in 2005 to 0.26453 in 2025. Field surveys documented only 16 tree species in 2025, representing severe biodiversity loss compared to historical diversity. These findings revealed complete landscape transformation from a natural ecosystem to an urbanized environment, resulting in total habitat destruction, loss of ecosystem services, hydrological disruption, and biodiversity collapse. It is recommended that campus planning incorporate mandatory green infrastructure, sustainable urban drainage systems, and stringent land-use controls to mitigate environmental degradation and promote sustainability.

This study was carried out to determine the genotoxic effects of varying treatments of non- alcoholic beverage industrial effluent on the expression of juvenile Clarias gariepinus genes. Tissue samples were extracted from juvenile C. gariepinus gills followed by RNA isolation, quantification and normalization of the isolated RNA, synthesis of complementary DNA, and agarose gel electrophoresis.

This study explores the harmful effects of lead acetate exposure on the kidneys, liver, and blood in Wistar rats, aiming to shed light on potential risks to human health from this common environmental toxin. Over a four-week period, adult Wistar rats were divided into four groups: a control group receiving distilled water and three treatment groups administered varying doses of lead acetate (low, medium, and high) via oral gavage. Weekly assessments included hematological analyses such as complete blood counts, measurements of inflammatory markers like TNF-α in liver and kidney tissues, and oxidative stress evaluations through assays for key enzymes and antioxidants. Results revealed dose- dependent disruptions, with treated groups showing significant reductions in hemoglobin, platelet, and white blood cell counts, alongside elevated neutrophil and lymphocyte levels indicative of immune stress. In the liver and kidneys, heightened TNF-α concentrations pointed to progressive inflammation, while oxidative stress markers demonstrated increased lipid peroxidation and depleted antioxidant defenses, particularly in higher-dose groups by week four. These findings underscore lead acetate's capacity to induce organ damage through oxidative and inflammatory pathways, highlighting the need for stricter controls on lead exposure in industrial and everyday settings to prevent similar toxicities in humans.

This study assessed the physicochemical and microbial characteristics of sediments from the Orhionmwon River, Edo State. The result of the average mean concentration of the physicochemical and microbial parameter are 5.03 ± 0.20( PH), 43.67 ± 10.44 µS/cm, 1212.61 ± 165.52 mg/kg (calcium), 287.33 ± 93.92 mg/kg (Magnesium), 297.91 ± 81.39 mg/kg, (Potassium) 161.62 ± 32.71 mg/kg (sodium), 0.05 ± 0.01 (Nitrogen), 0.51- 0.16 (TOC), 92.18 ± 2.39(sand), 5.94- 2.38(clay), 1.88 - 0.03(slit), 27.24 ± 10.41(THC), 4.00 ± 1.01 (THC), 1.52 ±0.31(THF), 73.11 ± 11.39( E.coil), and 187.78 - 36.46 (coliform) respectively . Sand and slit showed no significant difference (p>0.05), why pH, EC, calcium, magnesium, potassium, sodium, nitrogen, TOC, clay, THC, THB, THF, E.coli and coliform respectively exhibit a significant difference (p <0.05) across the three sampling stations . The study concluded that the microbial parameters in the sediments were very high. The findings highlight both natural geological influence and serious human impact, posing a clear public health risk. It recommends regular sediment monitoring and urgent improvements in waste management to protect both the environment and community health.

This study investigates the presence and abundance of microplastic contamination in a commercially important fish species, Mormyrus rume from Ikpoba River Benin City. A total of sixteen samples of Mormyrus rume (n=16) were collected from three designated stations along the river with the help of artisanal fishermen. The fish samples were then dissected for Gastrointestinal Tract (GIT) removal. The Gastrointestinal Tract was digested for microplastic extraction and density gradient techniques were used to isolate microplastic. The polymer composition of microplastic was confirmed using Attenuated Total Reflectance- Fourier Transform infrared (ATR-FTIR) spectroscopy. The result showed that samples from station 3 had the highest microplastic contamination, with an abundance of 40.53% while samples from station 1 had the least with an abundance of 26.63%. A total of eight plastic polymers were identified, polyethylene terephthalate (PET), polyethylene (PE), polyamide (PA), polyurethane (PU), polypropylene (PP), polystyrene (PS), polycarbonate (PC), and polyvinyl chloride (PVC). The polymer count was recorded in an increasing order of PET>PP>PA>PE>PS>PU>PC>PVC across all the stations. This study confirms the presence and abundance of microplastics in fish samples and indicate that fish from the river may pose human health risks to consumers due to bioaccumulation and biomagnification. The findings emphasize the need for better waste management practices, public awareness and improved urban drainage systems.

Geophagy, the deliberate consumption of clay or soil, is a common cultural practice in many
parts of the world, including Nigeria. Although often believed to have therapeutic benefits, some
geophagic clays may contain toxic elements that pose health risks. This study assessed the
toxicity potential of Uzalla geophagic clay by exposing Drosophila melanogaster to varying
concentrations of the clay and assessing their survival rate, locomotor performance, and
neurotoxic gene expression. Flies were exposed to different concentrations of the clay (0.025
g/mL, 0.05 g/mL, and 0.1 g/mL) for five days, and assessments were made on survival rate,
locomotor performance (negative geotaxis), and neurotoxic gene expression. The results revealed
a concentration-dependent decline in survival, with the highest mortality recorded at 0.1 g/mL.
However, negative geotaxis assays indicated improved locomotor performance across all
exposed groups in contrast to the control group, suggesting a possible stimulatory effect. Gene
expression analysis showed upregulation of Spitz, Eiger, and Hedgehog, reflecting activation of
stress and neuroprotective pathways, while Wingless and Keap1 were downregulated, indicating
oxidative imbalance and neuronal disruption. This study shows that Uzalla geophagic clay
exhibited neurotoxic potential at higher concentrations, evidenced by reduced survival, altered
locomotor performance, and disrupted gene expression associated with neural stress.

This study evaluated the operational and health risk factors associated with municipal solid waste scavenging in two privately-operated municipal Solid waste dumpsites in Benin City, Edo State. Awell- structured questionnaire was administered to 100 randomly selected scavengers; the questionnaire covered demographics, personal details, and information on the types and frequencies of health hazards encountered by waste scavengers, providing insights into the challenges they face. The findings revealed significant health risks including injuries, respiratory problems, and gastrointestinal illnesses, highlighting the need for interventions to improve the safety and well-being of the scavenging operations. Furthermore, they also face several operational risks due largely to the lack of use of personal protection equipment, resulting in cuts, respiratory issues, and gastrointestinal illnesses, with a notable proportion experiencing frequent headaches and a high prevalence of malaria. We recommend that the operators of the dumpsites should be regulated by the Edo State Waste Management Board, with strict guidelines and punitive measures put in place for lack of compliance. On the part of the dumpsite operators, they should provide all necessary personal protection equipment and enforce their use as a standard operating procedure. Furthermore, first aid equipment for staff, drinking water and bathrooms with soap and water for their sanitation should be provided.

This study was carried out to determine the concentrations of some heavy metals such as nickel, cadmium, mercury and oxidative stress status of tomatoes sold in local markets in Benin City, Edo State, Nigeria. Fresh tomatoes samples were brought from Uselu and Ikpoba hill market in Benin City. The samples were oven-dried at 105°C for 24 hour and grinded to powder. The powdered samples were dissolved in deionized water, filter through whatman filter paper and the volume was made up to 25 ml using 10 ml of 98% nitric acid. The resulting solution was analysed for the presences of heavy metal using using Atomic Absorption Spectrophotometer (AAS, Perkin Elmer model 2130). The results showed that the nickel concentration present fresh tomatoes samples obtained from the two markets ranged from 0.13 mg/kg to 0.16 mg/kg, while the cadmium concentration ranged from 0.11 mg/kg to 0.13 mg/kg. However when compared to W.H.O standard the heavy metal concentration were slightly above the recommended value of 0.10 mg/kg. Also oxidative stress analysis showed that the superoxide dismutase (SOD) value ranged from 3.02 U/g to 3.48 U/g, Catalase (CAT) value ranged from 0.08 U/g to 0.10 U/g , Glutathione peroxidase (GPx) value ranged from 4.96 U/g to 5.73 U/g, while Malondialdehyde (MDA) value ranged from 0.50 U/g to 0.64 U/g respectively. These findings were indicative of environmental pollution due to industrial and vehicular emissions and also the mode of handing and processing of the samples. Although the heavy metals detected in this study are not beneficial to man and plant, low concentration can prove detrimental to health.