Determination and fractionation of potentially toxic elements in urban particulates

Urban environmental pollution is of increasing concern. There is a need for improved analytical methods to assess risk from potentially toxic elements in urban soils and related material. This thesis focuses on development and application of such methods, notably the modified BCR sequential extraction procedure. The analytes studied were Cr, Cu, Fe, Mn, Ni, Pb and Zn, and quantification was by ICP-AES and ICP-MS. Results obtained by BCR extraction of urban allotment soils were compared with those from aqua regia digestion, 0.05 M EDTA extraction, and the SBET. Correlation analysis and principal component analysis (PCA) grouped analytes into a set mainly of lithogenic origin (Cr, Fe, Mn,Ni) and another of mainly anthropogenic origin (Cu, Pb, Zn). The PCA indicated relationship between amounts of analytes released in step 1 of the sequential extraction and EDTA-extractable analytes, and between results of the SBET method and those obtained with EDTA. The BCR extraction was then miniaturised for application to urban airborne particles. The fractionation pattern was not affected by reducing the sample mass from 1 g to 0.0625 g for particles < 45 μm and 500 - 1000 μm in diameter, but changing the size of vessel used did have an effect. When the miniaturised extraction was applied to test samples presented on filter dynamics measurement system (FDMS) filters a significant Zn blank was found. Despite this, recoveries within 30 % of certified values were obtained when 0.1 g test portion of BCR CRM 701, loaded onto FDMS filters, were extracted. Finally, the chemometric identification of substrates and element distribution (CISED) method was miniaturised and adapted for application to particulate samples on FDMS filters. Four distinct physicochemical components were extracted from BCR 701 using the traditional CISED method, but 11 components when the CRM was loaded onto a filter. The mobilities of the PTE as predicted by the CISED were in good agreements with fractionation patterns obtained using the BCR sequential extraction protocol.Urban environmental pollution is of increasing concern. There is a need for improved analytical methods to assess risk from potentially toxic elements in urban soils and related material. This thesis focuses on development and application of such methods, notably the modified BCR sequential extraction procedure. The analytes studied were Cr, Cu, Fe, Mn, Ni, Pb and Zn, and quantification was by ICP-AES and ICP-MS. Results obtained by BCR extraction of urban allotment soils were compared with those from aqua regia digestion, 0.05 M EDTA extraction, and the SBET. Correlation analysis and principal component analysis (PCA) grouped analytes into a set mainly of lithogenic origin (Cr, Fe, Mn,Ni) and another of mainly anthropogenic origin (Cu, Pb, Zn). The PCA indicated relationship between amounts of analytes released in step 1 of the sequential extraction and EDTA-extractable analytes, and between results of the SBET method and those obtained with EDTA. The BCR extraction was then miniaturised for application to urban airborne particles. The fractionation pattern was not affected by reducing the sample mass from 1 g to 0.0625 g for particles < 45 μm and 500 - 1000 μm in diameter, but changing the size of vessel used did have an effect. When the miniaturised extraction was applied to test samples presented on filter dynamics measurement system (FDMS) filters a significant Zn blank was found. Despite this, recoveries within 30 % of certified values were obtained when 0.1 g test portion of BCR CRM 701, loaded onto FDMS filters, were extracted. Finally, the chemometric identification of substrates and element distribution (CISED) method was miniaturised and adapted for application to particulate samples on FDMS filters. Four distinct physicochemical components were extracted from BCR 701 using the traditional CISED method, but 11 components when the CRM was loaded onto a filter. The mobilities of the PTE as predicted by the CISED were in good agreements with fractionation patterns obtained using the BCR sequential extraction protocol

Microbial quality of meat floss ‘dambun nama’ processed from broiler chickens fed graded levels of ‘sabara’(Guiera senegalensis) leaf meal

This study evaluated the microbial quality of meat floss processed from broiler chickens fed graded levels of Guiera senegalensis leaf meal (GSL) at 0.0% (GSL1), 7.0% (GSL2), 14.0% (GSL3) and 21.0% (GSL4). These were packaged and stored into four (4) different packaging media; Foil Paper Pack (FPP), Wrapped Newspaper Pack (WNP), Plastic Container Pack (PCP) and Disposable Container Pack (DCP). These products were stored and monitored for contaminations at 0, 4, 8 and 12 week intervals. Means were analysed and compared with passable and safe limits of 107cfu/g. The results showed that at 1st day of storage, there were no fungal counts in GSL3 and GSL4 was having the least count of 2.0 x 105. The control (GSL1) had the highest total bacterial count of 24.0 x 105cfu/g. At 12th week of storage, the results showed that the total fungal counts were 0.00, 0.00, 0.00, and 2.0 x 105cfu/g for GSL2, GSL3, GSL4 and GSL1, respectively. The overall effects showed that the total microbial load of meat floss decreased as the concentrations were increased. The results showed that GSL2 (2.0 x 105cfu/g) and GSL3 (3.0 x 105cfu/g) had lower total bacterial counts than GSL1 (24.0 x 105cfu/g) and GSL4 (8.0 x 105cfu/g) across the packaging media at first week (0 week) of storage. WNP had the least bacterial counts (1.0 x 105cfu/g). Conversely, DCP had the highest counts (21.0 x 105cfu/g) across the treatment groups and packaging media. At higher week of storage (12th week), GSL2 (15.0 x 105cfu/g) and GSL3 (18.0 x 105cfu/g) were lower than GSL1 (20.0 x 105cfu/g) and GSL4 (26.0 x 105cfu/g) for bacterial counts. WNP (10.0 x 105cfu/g) had the least counts across the treatments. Storage at higher weeks (8th and 12th) reduced fungal growth in most of the packaging media. This study concludes that the packaging method had suppressive effects against microbial growth. It is suggested that meat floss processed from broiler chickens fed graded levels of GSL should be evaluated for storage above the 12-week period

Field identification of Typha species in Hadeja Gashua Nguru wetlands

Field identification of Typha species in Hadeja Gashua Nguru wetlands Nigeria between January/June 2008. and July/October 2008. The study was conducted at Gashua Nguru wetland (Yobe and Jigawa states), Nigeria. The three sampling stations were established. Aquatic Plant Control information system Table (1996), for identify the species of Typha species was used, in three sampling station. Two Typha species were identified T. latifolia and T. angustifolia. Data analysis showed that, there was significant difference between T. latifolia and T. angustifolia (P<0.05)

Assessment of heavy metals bioavailability in dumpsites of Zaria Metropolis, Nigeria

The objectives of this study was to investigate the chemical fractionation, mobility and bioavailability of Cd, Cu, Mn, Pb and Zn in refuse waste soils of some dumpsites in Zaria metropolis. The heavy metals in the waste soils samples were sequentially extracted and measured using atomic absorption spectrometry. Mean of total extractable metals in the samples analysed for Cd, Cu, Mn, Pb and Zn ranged from 25.86 – 95.71, 1.70 – 446.43, 141.92 – 423.22, 39.9 – 739.10, and 122.45 – 511.57 mgKg-1 dry weight, respectively. Cd and Pb were mostly found to be in the mobile phase of the samples indicating that the metals are potentially more bioavailable to the environment than the other metals studied. Overall, the order of mobility and bioavailability of the metals is Cd > Pb > Zn > Mn > Cu

The Potential of Amaranthus caudatus as a Phytoremediating Agent for Lead

The potential of Amaranthus caudatus as a phytoremediating agent was studied, using lead spiked soil to grow the plants. The effect of the concentration of lead on plant growth was studied. The main aim of the study was to assess the accumulation of lead (Pb) in different compartments of the plant. The plants were grown in soils treated with solutions corresponding to 25, 50, 75 and 100 ppm of Pb. The plants were than separated into roots, stems and leaves and dried at 600C in a convection oven for 48 hours.The metals from the plant were extracted using wet digestion process. Pearson’s coefficient correlation analysis was used to measure the relationship between Pb concentration in the soil and in plant tissues. The highest concentration was recorded in the roots of plants at 50 ppm concentration. A. Caudatus plants exposed to 25 ppm of Pb showed highest increase in root and stem growth. The lowest root growth was observed in plants exposed to 100 ppm of Pb. There is a negative relationship between the concentration of Pb in the soil and that in the above ground plant tissues. Key Words: Accumulation, Amaranthus, Lead, Phytoremediation

Gas Chromatography-Mass Spectrometry and Fourier Transformed Infra-Red analysis of Senna occidentalis root

Senna occidentalis Linn is a member of the Fabaceae family (Leguminosae family). Different parts of the plant have been used in Hausa traditional medicine to treat various ailments ranging from microbial infections, jaundice and body weakness to fevers. The roots, leaves, flowers and seeds have been employed in herbal medicine around the world in various treatments. Senna occidentalis root was extracted using distilled water and methanol and was used to carry out phytochemical screening which revealed the presence of carbohydrates, monosaccharides, reducing sugars, combined reducing sugars, tannins, free anthraquinones, cardiac glycosides, glycosides, terpenoids, saponins, flavonoids and alkaloids. Fractionation of the methanol extract was done with four different solvents. The ethyl acetate fraction was further used for thin layer chromatography (TLC) and column chromatography (CC) and the sub-fractions obtained were coded ARE-GRE. Gas Chromatography-Mass Spectrometry (GC-MS) analysis was performed on ARE sub-fraction where fifteen different phytochemical compounds were identified. Fourier Transformed-Infra Red (FT-IR) analysis also showed sixteen peaks of different shapes and wavelengths. The presence of these phytochemicals in the roots of the plant could justify its use in traditional medicine to treat antimicrobial infections and other diseases

Influence of sensory attributes and storage media on quality of meat floss ‘‘dambun nama’’ processed from white meat

This study investigated the effects of storage period (≤ 5 weeks) and packaging media (glassware and stainless steel containers) on the quality of dambun nama processed from white meat (mature local chicken, duck, guinea fowl, turkey and fish). The results showed that there were significant (P&lt;0.05) differences among the white meat type with respect to taste, appearance, tenderness, colour and acceptability. The results also revealed that flavour and aroma did not differ significantly across the meat types. There were many significant and positive correlations among the attributes studied. For instance, correlations between appearance vs colour (r = 0.66) (P&lt;0.05) while the least correlation was between tenderness vs acceptability (r = 0.24) (P&lt;0.05). However, the results also revealed significant (P&lt;0.05) differences in the storage of dambun nama from the white meat studied. The quality of the product deteriorated with the increase in storage period. Dambun nama stored at lower weeks (1st and 2nd weeks) were better than those kept at 4th and 5 th week. However, dambun nama processed from guinea fowl and turkey meat deteriorated faster than the other types of white meat (fish, local chicken and duck) in terms of the total fungal and bacterial counts. However, at 5th week of storage dambun nama from duck meat had the lowest total microbes of 16.5 x 104cfu/g and followed by local chicken with 18.0 x 104cfu/g. There were also significant (P&lt;0.05) differences in the storability of the two media; with stainless steel container having the lowest counts in terms of both the fungal and bacterial counts than glassware medium. The study suggests that variation existed in the shelf-life of dambun nama processed using the different white meat. Storage of dambum nama in stainless steel containers prolonged the shelf-life longer than glassware containers. It is also suggested that most panellists showed preference towards dambun nama from turkey and local chicken meat. However, the less preferred white meat can be greatly improved through artificial manipulation of the sensory attributes that have strong relationships. Key words: White meat, Dambun nama, Sensory attributes, Storage medi

Performance of pearl millet variety LCIC-MV1 in a pearl millet-cowpea-based system in Nigeria

The performance of a new pearl millet (Pennisetum glaucum) cultivar LCIC-MVI in a traditional and improved intercropping system with cowpea was determined in a field experiment in Nigeria, in 1999. In traditional intercropping, pearl millet and cowpea were sown in 1 : 1 ratio, while in the improved system, 2 rows of pearl millet cv. LCIC-MV1 were cropped with 4 rows of cowpea cv. IT 90K 277-2. The improved system produced higher pearl millet stover and grain yields than the traditional system

Comparison of two non-specific flow-through sequential extraction approaches to identify the physico-chemical partitioning of potentially harmful elements in a certified reference material

Two non-specific sequential extraction methods utilising chemometric data processing (chemometric identification of substrates and element distribution, CISED) have been developed and used to determine the physico-chemical partitioning of potentially harmful elements (PHE) in certified reference material BCR CRM 701 (lake sediment). A miniaturized centrifugation method in which the sample was extracted on a filter insert in a polypropylene centrifuging tube, and a quasi-flow through method in which the sample was supported on a TX40 filter in a 47 mm in-line polycarbonate filter holder, gave similar results. The CISED data processing identified nine components. Seven of these were of geochemical origin – two carbonate components, an Al/Fe oxide/hydroxide component, three Fe-dominated components and one Si-dominated component – while the others represented the TX40 filter blank. The overall extraction capabilities of the methods were similar to that of the well-established BCR sequential extraction (Σsteps 1–3). However, whilst the BCR extraction is operationally defined, the CISED provides information on associations between PHE and the geochemical components identified. The flow through CISED procedure has potential applications in investigating the chemical speciation of PHE associated with urban airborne particular matter

Case Report Common Atrium: A Rare Cause of Acute Decompensated Heart Failure

We report a rare case of common atrium and acute decompensated heart failure most likely precipitated by acute bacterial pericarditis leading to premature death, in a 25-year-old male footballer. The silent course of the disease for decades as well as the diagnostic and management pitfalls of this case illustrates the importance of early detection by echocardiography and urgent appropriate treatment in intensive care settings to limit the poor prognosis of the condition