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INTRODUCTION: Effective utility of mixed waste in the landfills lies before its complete degradation rather than after landfill closure. The elemental and chemical constituents of an active and a closed landfill composite were compared... more
INTRODUCTION: Effective utility of mixed waste in the landfills lies before its complete degradation rather than after landfill closure. The elemental and chemical constituents of an active and a closed landfill composite were compared using Fourier transform - infrared (FTIR) spectroscopy, scanning electron microscope / energy-dispersive X-ray (SEM/EDX) spectroscopy, and proximate analysis in order to determine potential alternative uses. METHOD: Landfill sites were systematically gridded into seven cells according to RCRA USEPA guidelines. Three samples were obtained from each cell at upper (0-15cm), mid (16-35cm) and low- (36-50cm) depths, both during the dry and wet seasons. The dried samples were separated by size into composites of less degraded (S> 0.63mm) and more degraded (S<0.63mm) components and homogenised. Proximate parameters (ash, volatile and fixed carbon) of samples were determined by ASTM D3174-5 methods. An Alpha attenuated total reflectance -FTIR spectrometer (Bruker) and X-Max SEM/EDX Instruments were used to evaluate the functional and elemental properties. RESULTS: both landfills had similar major elemental constituents representing 96.5% and 98.4% of elemental composition for the closed (O > C > Si> Fe > Ca >Al) and active(C > O > Si > Al > Ca > Fe) landfill samples. Cluster analysis revealed that elemental similarities were more influenced by the level of composite degradation (more degraded / less degraded) than by depth or seasonal variations. FTIR absorption peaks of both landfill samples indicated mineralised waste constituent with some distinguishing peaks peculiar to each landfill. The average ash content (>51%) of the waste in both landfills was above the level considered suitable for energy recovery from waste. DISCUSSION: The absence of major organic peaks precludes use of the waste for soil enrichment and anaerobic digestion feeds, but not for landfill covering. These findings, from rapid and amenable spectroscopic techniques, inform strategic management decisions for landfills
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Microwave acid digestion of solid samples combined with inductively coupled plasma – mass spectrometry (ICP-MS) provides a viable approach to quantification of heavy metals within landfill waste. The efficiency of Aqua regia and HNO3 in... more
Microwave acid digestion of solid samples combined with inductively coupled plasma – mass spectrometry (ICP-MS) provides a viable approach to quantification of heavy metals within landfill waste. The efficiency of Aqua regia and HNO3 in microwave digestion of both closed and active landfill composites was compared, with a view to relating heavy metals distribution to the particle size of the landfill composites. Landfill sites were systematically gridded into seven cells according to RCRA USEPA guidelines. Three samples were obtained from each cell at upper (0-15cm), mid (16-35cm) and low- (36-50cm) depths. The particle size was determined using the sieving method and grouped as less degraded (S> 0.63mm) and more degraded (S<0.63mm) components and homogenised. Microwave digestion of samples was carried according to the EPA3052 method using a CEM MARS Xpress digester. An Agilent 7500 ICP-MS was used to determined metal concentrations in digested samples. For 77% of the eleven USEPA toxic heavy metals investigated, microwave digestion with Aqua regia resulted in higher concentration of metals than with HNO3. Extraction precision for both acids was within acceptable limit for more degraded samples (RPD10%) a higher burden of heavy metals in closed landfill samples than active landfill samples, except for Ag and Zn. The more degraded component of both landfills had elevated concentrations of heavy metals (>4% for HNO3 and >6% for Aqua regia). Sample recoveries based on CRM analysis showed that both acids were within the same accuracy (between 88% and 95%
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Assessment of Progress in Marine Pollution Control Assessment of Progress in Marine Pollution Control (including land-based sources of Pollution) and (including land-based sources of Pollution) and Challenges to the Implementation of the Oceans-related Challenges to the Implementation of the Ocea...more
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In this study, the levels of organochlorine pesticide (OCPs) in Ogun River, at Kara abattoir were investigated to estimate the extent of pesticide pollution in the river. Two sets of water and sediment samples (A and B) were collected.... more
In this study, the levels of organochlorine pesticide (OCPs) in Ogun River, at Kara abattoir were investigated to estimate the extent of pesticide pollution in the river. Two sets of water and sediment samples (A and B) were collected. Samples A were collected in April (during heavy downpour) and samples B in June (under dry weather condition). Most of the physico-chemical parameters in the water and sediment samples were within WHO limits, except the samples taken during heavy downpour. In the water samples, the DDT and metabolites (2.023±0.586 µg/L), endrin (0.671±0.256 µg/L) and aldrin and dieldrin (8.290±2.891 µg/L) exceeded 1 µg/L, 0.6 µg/L and 0.03 µg/L respectively in the WHO (2006) guideline, whereas lindane (0.046±0.034 µg/L) and methoxychlor (0.757±0.281 µg/L) were below 2 µg/L and 20 µg/L respectively in the guideline. OCP residual levels in samples A were much higher than in B. This could be attributed to the massive draining and heavy disturbance of the river during the...
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The Lagos lagoon is one of Africa's largest estuarine ecosystems. Its water receives organic input from a wide variety of sources; atmospheric, industrial, and municipal activities. Environmental impacts from PAHs continue to elicit... more
The Lagos lagoon is one of Africa's largest estuarine ecosystems. Its water receives organic input from a wide variety of sources; atmospheric, industrial, and municipal activities. Environmental impacts from PAHs continue to elicit global concern and attract attention especially in Lagos and its environs. Some PAH compounds which are toxic, mutagenic, or carcinogenic could be taken up and accumulated by aquatic organisms from polluted water, thereby resulting in the modern day diseases in humans. This research aims at assessing the decline of the water quality of Lagos lagoon due to land-based human activities in order to reveal the extent of exposure of humans to PAH risk. The research presents the need for control measures necessary for the minimization or prevention of PAH pollution to ensure a safe environment for our people. All the 16 USEPA priority PAHs were present across all twelve locations in high concentrations irrespective of the distance from the source point. The...
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Food smoking belongs to one of the oldest technologies of food preservation which mankind has used in fish processing. Potential health hazards associated with smoked foods may be caused by carcinogenic components of wood smoke – mainly... more
Food smoking belongs to one of the oldest technologies of food preservation which mankind has used in fish processing. Potential health hazards associated with smoked foods may be caused by carcinogenic components of wood smoke – mainly polycyclic aromatic hydrocarbons (PAHs) and derivatives of PAH. Comparison of the concentration of PAHs in smoked fish samples processed by sawdust, charcoal and firewood were investigated with the aim of determining the process that contributed more concentration of the PAHs to the fish samples. For this study, three species of fishes were investigated: Arius heude loti (cat-fish), Cynoglossus senegalensis (sole) and Haake (fresh stock fish). The PAHs in the samples were extracted using solvents by ultrasonication and were analysed for the 16 US EPA polycyclic aromatic hydrocarbons using HPLC with a UV DAD detector. The results showed that smoked fish samples that were processed by charcoal gave the lowest level of total PAHs, followed by firewood m...
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While most universities in the developed world, by tradition, have research offices to handle research management, structures for the efficient coordination and strong governance of research are nascent within many Sub-Saharan African... more
While most universities in the developed world, by tradition, have research offices to handle research management, structures for the efficient coordination and strong governance of research are nascent within many Sub-Saharan African universities. In this paper we look at the organizational structures, policies and functions of research offices for supporting faculty research as well as their management operations in 5 selected Nigerian universities. The authors interviewed 20 participants from 5 selected federal universities in Nigeria. Five directors of the research offices and 15 research administrators participated. Findings identified existing infrastructure for research management, the challenges facing newly created research offices in Nigerian universities, and strategies employed by research offices to tackle identified problems. Findings also showed how policies, practices, institutional structures and support models for research governance are shifting to align with inte...
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Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic pollutants which get into foods during processing. In spite of this, only a few studies have been carried out on Nigerian delicacies. Raw and roasted food samples of corn (Zea... more
Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic pollutants which get into foods during processing. In spite of this, only a few studies have been carried out on Nigerian delicacies. Raw and roasted food samples of corn (Zea mays), ripe plantain, unripe plantain (Musa paradisiaca) and yam (Dioscorea sagittifolia) of southwest Nigeria were evaluated for nutritional (proximate analysis and macro nutrients) and anti-nutritional qualities PAHs. The starchy food samples consist mainly of carbohydrate ranging from 35.93 - 55.52%, percentage crude fibre, protein, crude fat and ash content ranged between 0.82 - 14.21%, 3.15 - 8.27%, 1.12 - 19.56% and 1.12 - 2.59% respectively. The gross energy content of the food samples ranged from 777 - 1678 KJ/100g. The concentrations of minerals (macro nutrients) were as follows: Copper (7.05-20.60 ppm), Iron (3.15-28.3 ppm), Magnesium (1.15-4.95 ppm), Manganese (0.70-3.80 ppm) and Zinc (1.05-9.60 ppm). Higher levels of PAHs were found in the ro...
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Cassava, a staple crop in Nigeria, processed by numerous factories in rural and sub-urban locations is known to contain some level of cyano compounds. Lack of stringent environmental regulations on management of cassava wastewater (CWW)... more
Cassava, a staple crop in Nigeria, processed by numerous factories in rural and sub-urban locations is known to contain some level of cyano compounds. Lack of stringent environmental regulations on management of cassava wastewater (CWW) from cassava processing factories had led to its indiscriminate discharge on the environment. CWW samples were obtained from cassava processing factories from selected states (Lagos (A), Oyo (B), Ogun 1 (C1), Ogun 2 (C2) and Cross River (D)) in Nigeria to determine the cytotoxic and genotoxic effects of extracted cyanide from the wastewaters. The cyanide was hydrolyzed via chemical degradation utilizing 1.25 M NaOH and subsequently titrated using silver nitrate with p-dimethylaminobenzalrhodamine as indicator. Further, in order to explore the potential toxicity of this pollutant present in the effluent, a battery of short-term biological assay (Allium cepa chromosomal aberration test) was used. Bulbs with roots of Allium cepa L. were treated with different concentrations (0.05%, 0.1%, 0.2%, 0.4%, and 0.8%) of CWW, and after 48 h the root tips were processed for cytological studies by the aceto-orcein squash procedure. The results revealed that cyanide concentrations on re-fluxing were in the range of 1.0 mg/L and 1.3 mg/L. All concentrations induced a number of chromosomal aberrations in the root tip cells. The mitotic index decreased significantly (p < 0.05) with increasing concentration. The cytotoxic effects showed strong concentration dependent root growth inhibition with EC50 values of 30, 20, 37, 43 and 22 % for A, B, C1, C2 and D, after 72 h. The findings thus indicate that alkali treatment is very efficient in degrading the cyanide content of CWW and has shown that the combination of physico-chemical analysis along with the sole toxicity assessment could provide valuable information about the sole toxicity of cyanide as a chemical pollutant present in the cassava effluent.
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Lithiation of toluenesulfonates (I), (XIII) occurs at the methyl group, as in (III).
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... projects usually call for initial comprehensive environmental assessment studies, ... street sweeping etc. The LAMATA is blazing an excellent trail in Public Transportation management in Nigeria. ... cities authorities need to... more
... projects usually call for initial comprehensive environmental assessment studies, ... street sweeping etc. The LAMATA is blazing an excellent trail in Public Transportation management in Nigeria. ... cities authorities need to mainstream environmental considerations ...
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Results of regression analyses and the individual variances explained by the investigated conditions. (DOCX 15Â kb)
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Research Interests: Environmental Science, Environmental Monitoring, Environmental Chemistry, Nigeria, Eutrophication, and 13 moreMedicine, Biological Sciences, Phosphorus, Environmental Sciences, Nitrogen, Airborne Particulates, Rain, Nutrient, CHEMICAL SCIENCES, Seasons, Potassium Compounds, Air Pollutants, and Sulfates
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Research Interests: Environmental Science, Environmental Monitoring, Environmental Chemistry, Urbanization, Nigeria, and 11 moreMedicine, Multidisciplinary, Phosphorus, Nitrogen, Airborne Particulates, Ammonia, Nutrient, Environmental monitoring and assessment, Fresh water, Particulate Matter, and Environmental Pollution Assessment and Monitoring
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The development of an effective and low-cost biomass to ethanol system has gained global recognition as the depletion of non-renewable energy resources and negative environmental issues surrounding fossil fuel combustion is increased.... more
The development of an effective and low-cost biomass to ethanol system has gained global recognition as the depletion of non-renewable energy resources and negative environmental issues surrounding fossil fuel combustion is increased. Environmental pollution and increasing health hazards associated with growing volumes of wood waste generated along the Lagos Lagoon in Nigeria has grown to unbearable limits. Sawdust from twenty different wood species along the Lagos Lagoon was subjected to Kraft-pretreatment in solubilizing its lignin component thus releasing cellulose fibers susceptible for saccharification by Trichoderma viride cellulase. The amount of sugars released was calculated after 30 min, 1 h, 3 h and 6 h of incubation with the cellulolytic enzyme. Different sugar releasing patterns were obtained from the various sawdust samples and after 6 h of degradation the highest sugar concentration of 13.50 mg.mL-1 was released from Lophira alata cellulose while the lowest concentrat...
Soils from 12 sites in Lagos area, Nigeria impacted by anthropogenic activities were extracted by ultrasonication and analysed for the concentration of 16 priority polycyclic aromatic hydrocarbons (PAHs) by gas chromatograph-mass... more
Soils from 12 sites in Lagos area, Nigeria impacted by anthropogenic activities were extracted by ultrasonication and analysed for the concentration of 16 priority polycyclic aromatic hydrocarbons (PAHs) by gas chromatograph-mass spectrometer (GC-MS). The concentration of the sum of PAHs ranged from 0.2 to 254 μg/g at these sites. The sum benzo[a]pyrene-equivalent dose (BaPeq) at the sites ranged from 0.0 (K, forest soil) to 16.7 μg/g (C, the lubricating oil depot soil). Mean daily intake (MDI) for the composite soils samples when compared that of food revealed that some of the individual PAH in samples from sites A (Dump site), C (Depot and loading point for used for black oil), F (Dump site), G(petroleum depot), H (Roadside) and L (Car park) exceeded the recommended the recommended MDI threshold for food, indicating some risk associated with activities on these sites based on this ingestion estimate exceeded value. 8.2 × 10(-6), 7.1 × 10(-7), 1.2 × 10(-4), 4.9 × 10(-7), 7.3 × 10(-...
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The Lagos Lagoon system is a brackish coastal lagoon—the largest in the West African coast with a large series of estuaries—located between longitude 3o23′ and 3o40′E and between latitude 6o27′ and 6o48′N. It is a shallow expanse of water... more
The Lagos Lagoon system is a brackish coastal lagoon—the largest in the West African coast with a large series of estuaries—located between longitude 3o23′ and 3o40′E and between latitude 6o27′ and 6o48′N. It is a shallow expanse of water (0.3–3 m deep), 50 km long and 3–13 km wide and separated from the Atlantic Ocean by a narrow strip of barrier bar complex. This report is on the levels of pollution and nutrients status of the Lagos Lagoon system including physicochemical properties, pesticides organochlorines (OC), polyaromatic hydrocarbons (PAHs), heavy metal species and nutrients observed between 2002 and 2008. Watersheds of the highways on the lagoon had higher concentrations of nutrients (phosphorus and nitrates) relative to other locations on the Lagoon. The western part of the Lagoon was found to have higher concentrations of Cd, Cu, Pb and Zn than the other points. Lagos Lagoon and the adjoining creeks show high anthropogenic input of PAHs and other persistent organic pollutants (POPs). The major hydrocarbon index in most samples was at C29, C31 and C27, indicating vascular plants sources. Mean PBT levels in water and in sediment increased with time between 2004 and 2007. PBT distribution in the lagoon followed the pattern, sediment > biota > water, though some exceptions occurred where the biota bioaccumulated more PBTs than are found in both sediment and water. The Lagoon biota bioaccumulated organochlorine pesticides above allowable limits and thus pose a high risk to human health. The levels of some pollutants in the Lagoon have negatively impacted on the environmental quality which has indirectly affected the social and economic activities of the dependants and this requires improved management strategies to ameliorate. Indeed with the high population that the estuary/lagoon system supports, consideration for its designation as an international waterbody and its concomitant attention is now paramount.