DEPARTMENT OF ENVIRONMENTAL MANAGEMENT AND TOXICOLOGY

Major contributions to the pollution in the atmosphere are Nitrogen dioxide (NO2) and Sulphur dioxide (SO2) from cement factories as well as other industrial activities in Urban and Rural areas. The study area covers Ibese, Paplanto, Abeokuta, Ewekoro and other rural areas as they play host to either cement factories or congested urban. This research compared the amount of NO2 and SO2 released into the atmosphere at Ibese, Papalanto and Abeokuta. Sentinel 5P data for the study area was used to monitor these pollutants. Google earth engine editor was used to extract the pollutants over the study area. The duration considered was a 4-month interval within year 2019 to 2021 which was used to present 3 spatial maps per year resulting in a total of 9 maps for both pollutants. SO2 concentration ranged between-0.000161 to 0.0000782;-0.000206 to 0.000162; 0.000194 to 0.000228, for 2019, 2020 and 2021 respectively. NO2 concentration ranged between 0.0000459 to 0.0000846, 0.0000491 to 0.0000947, 0.0000565 to 0.000122 mol/m2 for 2019, 2020 and 2021 respectively. The spatial distribution for both pollutants were regrouped into 4 classes namely low, moderate, high and very high. Ibese fell once within the low class, seven times within the moderate class, five times each within the high and very high class respectively considering both the NO2 and SO2 maps. Papalanto fell twice within the low class, once within the moderate class, six times within the high class and eight times within the very high class. Abeokuta fell six times within the moderate class and twelve times within the high class. The most dominant zone is the moderate zone followed by the high zone for SO2 and NO2 between 2019 and 2021. The frequency of occurrence of Papalanto and Ibese within the peak zone of SO2 and NO2 was very high when compared to the frequency of occurrence of Abeokuta which never fell beyond the high zone of either pollutant. This was attributed to the cement factory working nonstop located within Papalanto and Ibese.

Garri is a commonly consumed cassava product in Nigeria. Poorly processed/stored garri could pose serious health risk to consumers. This study seek to investigate the microbial evaluation of garri sold in open markets Benin City. Five garri samples were purchased from eight open markets which are; Egor market, Oba market, Ekiosa market, Oluku market and Adolor market, Ikpoba-Hill market, and Aduwawa market, all in Edo State making a total of 40 samples. 500 mg each for the sample and appropriately labeled. The samples were transported to the Environmental Management and Toxicology Department laboratory, for microbial, pH and moisture content analysis. Different media such as Potato Dextrose agar (PDA), Nutrient Agar (NA) were prepared separately. 1g of each sample (garri) was weighing on a weighing balance, dissolved properly in 10m1 of pepton water which was used to prepare ten folds serial dilution. Using pour plate method. The total number of bacteria, yeast and moulds in the garri samples was determined. The total number of colony forming unit (CFU/g) was calculated, the moisture content and pH of the garri samples were also calculated. Data obtained were analyzed in percentage and mean. Total Heterotrophic bacteria count in garri samples (cfu/g x103) indicated that Egor and Adolor markets had the highest heterotrophic bacteria count of (9.25 x103) respectively while Ikpoba Hill market had the lowest count of (1.00 x103). The highest fungal count was recorded in Ekiosa market (1.75) and the lowest was in New Benin market (0.50). The bacteria identified are; Micrococcus sp., Escherichia coli,: Klebsiella sp.,Lactobacillus sp Enterobacter sp., Staphylococcus aureus, Enterococcus sp., Pseudomonas sp,, Streptococcus sp., Shigella sp., Bacillus sp. the fungi identified are Rhizomucor sp., Aspergillus sp., Trichophyton sp., Geotrichum sp., Mudurella sp and Candida sp. The highest moisture content was noticed in Aduwawa market 16.80% sample C and last was in Oluku market 8.70% sample B. The highest pH was noticed in Oluku sample C (6.76) and the lowest pH was in Egor market sample A (4.11). There is therefore a need to maintain proper sanitary conditions so as to avoid health risks. The moisture content of garri samples analyzed is low and within standard specification, this could have accounted for keeping the microbial load of garri low.

This study was carried out to assess the effect of spent engine oil on the growth of two microalgae Monoraphidium contortum and Dimorphococcus lunatus. The test algae were grown in seven concentrations of 0% (control), 5%, 10%, 25%, 50%, 75% and 100% which were set up in triplicates. The growth response was monitored every two days for 14days using a visible spectrophotometer (Model No. HV-721). The percentage inhibition, percentage yield, growth rate, and cumulative growth rate and analysis of variance (ANOVA) were calculated using Microsoft Excel software. Physicochemical parameters were also assessed including, pH, total dissolved solids and electrical conductivity using prescribed methods. The results obtained showed that both microalgae species exhibited a positive growth response to the WSF, with Monoraphidium contortum consistently demonstrating higher growth compared to Dimorphococcus lunatus across all tested WSF concentrations. Statistical analysis using ANOVA indicated no significant difference (p > 0.05) in growth response among the various WSF concentrations for both species. However, temporal differences between measurements were statistically significant (p < 0.001). Percentage inhibition analysis revealed growth stimulation at low concentrations (5%, 10%, 25%, and 50%) and inhibition at high concentrations (75% and 100%) for both species, with Monoraphidium contortum showing higher inhibitory response relative to Dimorphococcus lunatus. Algal yield was enhanced at low to high concentrations (0-75%) for Monoraphidium contortum and low to moderate concentrations (0-50%) for Dimorphococcus lunatus. Growth rate analysis consistently favored Monoraphidium contortum across all WSF concentrations tested. Cumulative growth rate analysis suggested that Dimorphococcus lunatus may be less tolerant to WSF components compared to Monoraphidium contortum. Furthermore, total dissolved solids, electrical conductivity, and pH increased significantly on termination of the experiment. Based on the findings of this study, both microalgae showed bioremediation potentials and should be further studied

The health and safety of children is a contributing factor to attendance in school and optimum academic performance. Having access to water, sanitation and hygiene factors prevents disease outbreaks among other benefits. This study was carried out to assess the WASH status of Faith Immaculate College and May and Steve Academy in Egor Local Government Area of Edo State, Nigeria. Water samples were collected from both schools and subjected to analysis of selected physicochemical and microbiological parameters. The WASH status of the schools was evaluated using data gathered through a questionnaire. From the results obtained, the physicochemical quality of the water in the schools were all within the permissible limits for pH, chloride, nitrite and biochemical oxygen demand as recommended by the World Health Organisation. Microbiological analysis revealed that the total heterotrophic bacterial counts (3.5 x 10 1 - 8.0 x 10 1cfu/ml) and total fungal counts (2.0 x 10 1 - 5.0 x 10 1cfu/ml) were within permissible limits. However, the total coliform counts (4 - 17MPN/100ml) far exceeded the limit Centres for Disease Control limit and indicates a potential health risk when consumed. The bacterial isolates from this study were Escherichia coli, Klebsiella sp., Staphylococcus aureus and Bacillus sp. while the fungal isolates are Aspergillus niger, A. flavus, Mucor sp. and Penicillium citrinum. The antimicrobial susceptibility pattern showed that only ciprofloxacin was effective in the treatment of all bacterial isolates. The assessment of WASH status revealed that there was water available at both schools and the sanitary facilities were adequate, although waste management at Faith Immaculate College was not satisfactory. Therefore, it is recommended that water treatment be carried out to improve its quality, while more efforts should be made to improve waste management practices especially in Faith Immaculate College.

This project investigates the assessment of fecal waste management in rural community of Ekosodin, located in Benin City, Nigeria and its implications on local water sources. The rapid population growth and inadequate waste management
systems in rural areas have led to serious environmental challenges, especially concerning the management of fecal waste. This study explores the current waste management practices in the area, including open defecation, the use of pit latrines
and the challenges faced by residents in waste disposal. Data collection for this assessment involves field surveys and interviews with local residents to understand the extent of the problem. Additionally, water samples from key local sources such as
boreholes and reservoirs are tested for contamination levels, with a particular focus on fecal coliforms and physio-chemical parameters to evaluate the direct impact of fecal waste on water quality. The study also examines the relationship between poor waste management practices and the prevalence of waterborne diseases, such as cholera, dysentery and typhoid, which are common in rural communities with inadequate sanitation systems. The findings from this research highlight critical gaps in sanitation
infrastructure and the urgent need for intervention. The research advocates for the development of policies that encourage the provision of affordable, hygienic sanitation facilities in rural communities to ensure both environmental sustainability
and health of residents. In conclusion, the implication of inadequate fecal waste management in Ekosodin are far-reaching, affecting not only water quality but also overall public health and environmental integrity. Effective management of fecal
waste is crucial for safeguarding water resources and preventing the spread of IX waterborne diseases, ensuring a healthier and more sustainable future for rural communities like Ekosodin.

This dissertation focused on the effects of zinc oxide nanoparticles (ZnO NPs) on the African
catfish (Clarias gariepinus) embryotoxicity. The total protein levels in the embryos of Clarias
gariepinus were determined following a standard method after exposure to different
concentrations (0.0, 0.5, 1.0, 5.0, and 10.0 µg/L) of ZnO NP for 96 hours. The results showed
that there was a minor increment in the total protein levels at the exposure of Clarias gariepinus
embryos to 0.5 µg/L ZnO NPs and a significant increase in NP concentration at 1 µg/L. The
highest level of the total protein was recorded at the 10.0 µg/L concentration exposure of the
ZnO NP to the embryos. The effect of ZnO NP increases with increasing concentration of the
ZnO NP in a dose-dependent manner. Elevated total protein levels imply that there is a possible
inflammation or infection, and this could lead to adverse developmental challenges for the fish
embryos.

Air pollution remains a critical environmental and public health challenge in rapidly urbanizing regions. This study employs Sentinel-5P satellite data and Google Earth Engine (GEE) to analyze the spatial and temporal trends of carbon monoxide (CO), nitrogen dioxide (NO₂), and aerosols in Lokoja, Nigeria, from 2019 to 2024. As a major transit hub, Lokoja experiences significant pollution from vehicular emissions, industrial activities, and biomass burning,necessitating comprehensive monitoring. Results reveal dynamic fluctuations in pollutant concentrations, with CO levels peaking in 2024 due to increased fossil fuel combustion, while NO₂ concentrations spiked in 2021 before a gradual decline, suggesting the influence of regulatory interventions and shifts in energy consumption. Aerosol trends indicate seasonal variations, with pronounced increases post-2021 linked to dry-season biomass burning and industrial expansion. A paired sample t-test confirmed statistically significant year-to-year differences in pollutant levels, reinforcing the role of economic, policy, and environmental factors in air quality dynamics. This study underscores the importance of integrating satellite-based remote sensing with ground validation for enhanced air quality assessments. Findings provide critical insights for policymakers, advocating for emission control strategies, sustainable urban planning, and targeted mitigation efforts to safeguard public health and environmental sustainability in emerging urban centers.

Air pollution remains a critical environmental and public health challenge in rapidly urbanizing regions. This study employs Sentinel-5P satellite data and Google Earth Engine (GEE) to analyze the spatial and temporal trends of carbon monoxide (CO), nitrogen dioxide (NO₂), and aerosols in Lokoja, Nigeria, from 2019 to 2024. As a major transit hub, Lokoja experiences significant pollution from vehicular emissions, industrial activities, and biomass burning, necessitating comprehensive monitoring. Results reveal dynamic fluctuations in pollutant concentrations, with CO levels peaking in 2024 due to increased fossil fuel combustion, while NO₂ concentrations spiked in 2021 before a gradual decline, suggesting the influence of regulatory interventions and shifts in energy consumption. Aerosol trends indicate seasonal variations, with pronounced increases post-2021 linked to dry-season biomass burning and industrial expansion. A paired sample t-test confirmed statistically significant year-to-year differences in pollutant levels, reinforcing the role of economic, policy, and environmental factors in air quality dynamics. This study underscores the importance of integrating satellite- based remote sensing with ground validation for enhanced air quality assessments. Findings provide critical insights for policymakers, advocating for emission control strategies, sustainable urban planning, and targeted mitigation efforts to safeguard public health and environmental sustainability in emerging urban centers.

This study investigated the effect of water soluble fractions of crude oil on the growthofMonoraphidium contortum and Dimorphococcus lunatus over a 14 day period. The test algaewere grown in concentrations of CHU 10 nutrient media mixed with varying concentrationsof WSF of crude oil (5%,10%, 25%, 50%, 75% 100%) which were prepared in triplicates. The growth response was measured using a visible spectrophotometer at two day intervalsover a 14 day period. Physicochemical parameters (pH, EC, and TDS) were assessedonday14 of the experiment and were compared to the stock concentration before exposure tothetest microalgae. The results showed that there was growth stimulation for all concentrationsof 0%, 5%,10%, 25%, 50%,75%, and 100% from day 0 to day 2, and a lag phase fromday2to day 4 for 10% and 100%. The highest growth was recorded at 5% concentration onday14with an absorbance value of 0.035, followed closely by 100%, 50%, and 75%concentrations, while 10% WSF showed the least growth on day 14 with an absorbance value of 0.02. Statistically, the growth response of the microalgae to the WSF concentrations did not differsignificantly (p > 0.005). Generally the percentage yield was higher in M.contortumcompared to D.lunatus. The physicochemical properties of Dimorphococcus lunatus and Monoraphidiumcontortumshowed that when the quantity of WSF was reduced, both TDS and electrical conductivityrose. On the other hand, the pH revealed that it was somewhat more alkaline witha lowerWSF concentration, suggesting acidity with a higher WSF. To summarize, Dimorphococcuslunatus exhibited a strong inhibitory reaction, and Monoraphidium contortumis better suitedfor bioremediation of crude oil in contaminated water.

In the realm of nanotechnology, the utilization of nanoparticles has surged across diverse industries, ranging from electronics to medicine. Among these nanoparticles, aluminum oxide nanoparticles (Al2O3 – NPs) have gained significant attention due to their unique physicochemical properties. However, concerns regarding their potential toxicity have
prompted extensive research into identifying strategies to mitigate their adverse effects. This study aimed to investigate the effects of Al2O3 nanoparticles on testis and epididymis of male wistar rat. The effects were investigated using hormonal assay, and standard methods to
determine oxidative stress markers. In the current investigation, male wistar rats were given intraperitoneal doses of (Al2O3) 30 mg/kg, 50 mg/kg, 70 mg/kg, 100 mg/kg body weight over a period of seven (7) days. The result obtained showed the detrimental impact of Al2O3 – NPs
on reproductive health. It suggests that these harmful effects are closely linked to the nanoparticles' chemical composition, size, dosage, and duration of exposure. Specifically, the study highlights that Al2O3 – NPs can disrupt the production of sex hormones, leading to adverse effects on sperm quality and potentially resulting in infertility. Given the harmful
effects of aluminum oxide nanoparticles, the use of antioxidants is proposed as a measure to reduce potential risks associated with Al2O3 – NP toxicity on the testis and epididymis of male wistar rats.