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With growing international trade, food safety has emerged as an important global human health issue. One of the pathways by which extraneous contaminants such as toxic heavy metals access the human system is through food ingestion. At above permissible levels, these metals pose serious danger to human health. Cultivated farm produce on contaminated soil has the propensity to uptake and accumulate such contaminants. In this study, the prevalence and possible human health risks of toxic heavy metals such as Zinc, Cadmium, Copper, Lead, and Arsenic (Zn, Cd, Cu, Pb and As) in selected Instant Noodle Brands (INBs) from commercial outlets in Windhoek, Namibia was carried out. Different brands of instant noodle samples were purchased from four different commercial outlets for four periods with one-month interval. A total of 48 samples were collected and analysed for the level of heavy metals using mineral acid digestion method. Quantification of analysed metals in digested samples was done using Inductive Coupled Plasma -Optical Emission Spectrometer (ICP-OES). The mean concentration of heavy metals in the digested instant noodle samples across the sampling periods ranged from 13.1 – 17.9 mg/kg with overall mean concentration of 14.6mg/kg; 0.05 – 0.5mg/kg with overall mean level of 0.15 mg/kg; 1.5 – 2.4 mg/kg with overall mean concentration of 1.9 mg/kg; ND – 1.3 mg/kg with overall mean level of 0.4 mg/kg and 2.3 – 3.8 mg/kg with overall mean concentration of 1.4 mg/kg for Zn, Cd, Cu, Pb and As, respectively. A strong correlation (r = 0.99) was obtained between Zn and Cd levels but average correlation (r = 0.56) between Cd and Cu as well as between Cu and As (r= 0.55). Target Hazard Quotient (THQ) values greater than 1 (one) was obtained for Pb (1.7) and As (7.3). In addition, Carcinogenic Risk Index (CRI) values of 0.71 and 0.02 were also obtained for Pb and As, respectively. Of great concerns are the potential development of non-carcinogenic health effects and carcinogenic health risks with respect to these two toxic metals. Both metals are of no physiological benefits to the human system and very toxic at low levels. Hence, proper quality assurance protocol and monitoring of the level of toxic heavy metals in instant noodles products is recommended.

With growing international trade, food safety has emerged as an important global human health issue. One of the pathways by which extraneous contaminants such as toxic heavy metals access the human system is through food ingestion. At above permissible levels, these metals pose serious danger to human health. Cultivated farm produce on contaminated soil has the propensity to uptake and accumulate such contaminants. In this study, the prevalence and possible human health risks of toxic heavy metals such as Zinc, Cadmium, Copper, Lead, and Arsenic (Zn, Cd, Cu, Pb and As) in selected Instant Noodle Brands (INBs) from commercial outlets in Windhoek, Namibia was carried out. Different brands of instant noodle samples were purchased from four different commercial outlets for four periods with one-month interval. A total of 48 samples were collected and analysed for the level of heavy metals using mineral acid digestion method. Quantification of analysed metals in digested samples was done using Inductive Coupled Plasma -Optical Emission Spectrometer (ICP-OES). The mean concentration of heavy metals in the digested instant noodle samples across the sampling periods ranged from 13.1 – 17.9 mg/kg with overall mean concentration of 14.6mg/kg; 0.05 – 0.5mg/kg with overall mean level of 0.15 mg/kg; 1.5 – 2.4 mg/kg with overall mean concentration of 1.9 mg/kg; ND – 1.3 mg/kg with overall mean level of 0.4 mg/kg and 2.3 – 3.8 mg/kg with overall mean concentration of 1.4 mg/kg for Zn, Cd, Cu, Pb and As, respectively. A strong correlation (r = 0.99) was obtained between Zn and Cd levels but average correlation (r = 0.56) between Cd and Cu as well as between Cu and As (r= 0.55). Target Hazard Quotient (THQ) values greater than 1 (one) was obtained for Pb (1.7) and As (7.3). In addition, Carcinogenic Risk Index (CRI) values of 0.71 and 0.02 were also obtained for Pb and As, respectively. Of great concerns are the potential development of non-carcinogenic health effects and carcinogenic health risks with respect to these two toxic metals. Both metals are of no physiological benefits to the human system and very toxic at low levels. Hence, proper quality assurance protocol and monitoring of the level of toxic heavy metals in instant noodles products is recommended.&nbsp

This study examined the modes of handling of generated excess household solid wastes and attitude towards illegal disposal in Katutura township in Windhoek, Namibia. This was particu- larly significant because the capital city, Windhoek was once the cleanest city in Africa. Hence, the study aimed at generating data that would be of benefit to the local municipality towards review of waste management operational strategies and applicable local byelaw especially in this densely populated low-income township. A mixed method of qualitative (observational) and quantitative survey through the use of questionnaire was adopted. Presented data was based on a total of two hundred and thirty-four (234) respondents. Results showed that 46.6% of respondents were between the ages of 21-30 (43.7%) and employed with a 92.3% literacy level. About 66.7% were well aware of the concept of waste management and possessed the knowledge (94%) of its implementation. Majority of respondents (70.9%) generate wastes with- in the 240L waste bin volume per week while those that generate excess handle the wastes in several ways. About 44.3% place excess wastes beside the bin before municipal collection while a combination of 46.4% engage in different forms of illegal disposal. Ironically, about 77.8% of respondents were aware of what constitutes illegal waste disposal. A good number of respondents (62.1%) were satisfied with the municipal waste management. Suggestions on further improvements were however provided. Of great concern in this study was the apathetic attitude (50.4%) of respondents towards the illegal waste disposal practices. This might be contributing factor towards the loss of cleanliness ranking by the city.

In this study, total arsenic was determined in soil, common grass (Cenchrus ciliaris), plant leaf (Dogwood; Cornus florida) and an invertebrate (Stag beetle; Rhinotia hemistictus). This was with a view of investigating its distribution and level in the environment. Samples were randomly collected from stratified sections of the study area, processed and analysed using validated acid extraction technique. Detection of arsenic was by use of ICP-OES. Percentage recovery range of 78-92% was obtained and can be adjudged acceptable for application. Overall mean concentration of arsenic ranged from 0.35 ± 0.12 to 2.52 ± 1.85 mg kg-1; 0.01 ± 0.03 to 0.34 mg kg-1; 0.02 ± 0.03 to 0.46 mg kg-1 and 0.04 ± 0.02 to 0.72 ± 0.54 mg kg-1 across sampling sections 1 to 4 for soil, grass, leaf and insect samples respectively. Arsenic was detected in all samples, however levels obtained were below prescribed toxicity limits. Samples were highly contaminated based on contamination factors of > 6. The strong correlation coefficients (> 0.9) showed association between arsenic and analysed samples while analysis of variance revealed no statistical significant difference between arsenic and samples. The study revealed widespread distribution of arsenic in analysed samples which portend serious health implications across the food chain. Key words: Pollution, trace metal, grass, arsenic, environment, health, invertebrate, Namibia.

Nine metals (Fe, Cu, Mn, Ni, Cd, Pb, Hg, Cr, and Zn) were determined in soil and Digitaria eriantha plants within the vicinity of three coal power plants (Matla, Lethabo, and Rooiwal), using ICP-OES and GFAAS. The total metal concentration in soil ranged from 0.05 ± 0.02 to 1836 ± 70 μg g(-1), 0.08 ± 0.05 to 1744 ± 29 μg g(-1), and 0.07 ± 0.04 to 1735 ± 91 μg g(-1) in Matla, Lethabo, and Rooiwal, respectively. Total metal concentration in the plant (D. eriantha) ranged from 0.005 ± 0.003 to 535 ± 43 μg g(-1) in Matla, 0.002 ± 0.001 to 400 ± 269 μg g(-1) in Lethabo, and 0.002 ± 0.001 to 4277 ± 201 μg g(-1) in Rooiwal. Accumulation factors (A) of less than 1 (i.e., 0.003 to 0.37) at all power plants indicate a low transfer of metal from soil to plant (excluder). Enrichment factor values obtained (2.4-5.0) indicate that the soils are moderately enriched with the exception of Pb that had significant enrichment of 20. Geo-accumulation index (I-geo) values of metals indicate that the soils are moderately polluted (0.005-0.65), except for Pb that showed moderate to strong pollution (1.74-2.53).

Exposure to inorganic arsenic induces skin cancer and abnormal pigmentation in susceptible humans. High-throughput gene transcription assays such as DNA microarrays allow for the identification of biological pathways affected by arsenic that lead to initiation and progression of skin cancer and abnormal pigmentation. The overall purpose of the reported research was to determine knowledge building insights on biomarker genes for arsenic toxicity to human epidermal cells by integrating a collection of gene lists annotated with biological information. The information sets included toxicogenomics gene-chemical interaction; enzymes encoded in the human genome; enriched biological information associated with genes; environmentally relevant gene sequence variation; and effects of non-synonymous single nucleotide polymorphisms (SNPs) on protein function. Molecular network construction for arsenic upregulated genes TNFSF18 (tumor necrosis factor [ligand] superfamily member 18) and IL1R2 (interleukin 1 Receptor, type 2) revealed subnetwork interconnections to E2F4, an oncogenic transcription factor, predominantly expressed at the onset of keratinocyte differentiation. Visual analytics integration of gene information sources helped identify RAC1, a GTP binding protein, and TFRC, an iron uptake protein as prioritized arsenic-perturbed protein targets for biological processes leading to skin hyperpigmentation. RAC1 regulates the formation of dendrites that transfer melanin from melanocytes to neighboring keratinocytes. Increased melanocyte den-dricity is correlated with hyperpigmentation. TFRC is a key determinant of the amount and location of iron in the epidermis. Aberrant TFRC expression could impair cutaneous iron metabolism leading to abnormal pigmentation seen in some humans exposed to arsenicals. The reported findings contribute to insights on how arsenic could impair the function of genes and biological pathways in epidermal cells. Finally, we developed visual analytics resources to facilitate further exploration of the information and knowledge building insights on arsenic toxicity to human epidermal keratinocytes and melanocytes.

The distribution and potential sources of 15 polycyclic aromatic hydrocarbons (PAHs) in soils in the vicinity of three South African coal-fired power plants were determined by gas chromatography-mass spectrometry. PAH compound ratios such as phenanthrene/phenanthrene + anthracene (Phen/Phen + Anth) were used to provide reliable estimation of emission sources. The total PAH concentration in the soils around three power plants ranged from 9.73 to 61.24 μg g(-1), a range above the Agency for Toxic Substances and Disease Registry levels of 1.0 μg g(-1) for significantly contaminated site. Calculated values of Phen/Phen + Anth ratio were 0.48 ± 0.08, 0.44 ± 0.05, and 0.38 + 0.04 for Matla, Lethabo, and Rooiwal, respectively. Flouranthene/fluoranthene + pyrene (Flan/Flan + Pyr) were found to be 0.49 ± 0.03 for Matla, 0.44 ± 0.05 for Lethabo, and 0.53 ± 0.08 for Rooiwal. Such values indicate a pyrolytic source of PAHs. Higher molecular weight PAHs (five to six rings) were predominant, suggesting coal combustion sources. A good correlation existed between most of the PAHs implying that these compounds were emitted from similar sources. The carcinogenic potency B[a]P equivalent concentration (B[a] Peq) at the three power plants ranged from 3.61 to 25.25 indicating a high carcinogenic burden. The highest (B[a] Peq) was found in samples collected around Matla power station. It can therefore be concluded that the soils were contaminated with PAHs originating from coal-fired power stations.

This article investigates the impact of anthropogenic activities on an important surface water from physico-chemical, chemical and microbial perspectives. The surface water, referred to as Blesbokspruit is in the West Rand District of South Africa. Potential impactors include wastewater treatment plant, mines, farmlands and informal settlements. Water samples were collected from nine purposively selected sampling points and analysed in 2014. The mean values of analysed variables across sampling sites and periods ranged from pH: 7.4-8.4; EC: 93.0 - 146.6 mS/m; TSS: 11.3 – 39.0 mg/L; TDS: 590.3 - 1020.3 mg/L; COD: 15.6- 34.8 mg/L. Those for anions varied from NO3-: 0.2- 2.1 (mg/L) N; PO43- : 0.4-0.9 mg/L and SO42-: 118.6 - 379.5 mg/L. The metallic variables ranged from As: 0.01-0.06 mg/L; Cd: 0.02-0.06 mg/L; Fe: 0.04-0.73 mg/L; Cu: 0.02 – 0.05 mg/L and Zn: 0.05 – 0.15 mg/L. The Faecal coliform varied from 15.9-16878.5 cfu/100 ml; Total coliform: 92.9-430294 cfu/100 ml and HPC from 4322.5-39776 cfu/1ml. Detection of toxic metals and pathogenic organisms above target safety limits indicate unsuitability of the water for domestic use with impact on the health of aquatic ecosystem. The study generally revealed the impact of anthropogenic activities on the surface water quality.

Arsenic is a naturally occurring toxic metal and its presence in food could be a potential risk to the health of both humans and animals. Prolonged ingestion of arsenic contaminated water may result in manifestations of toxicity in all systems of the body. Visual Analytics is a multidisciplinary field that is defined as the science of analytical reasoning facilitated by interactive visual interfaces. The concentrations of arsenic vary in foods making it impractical and impossible to provide regulatory limit for each food. This review article presents a case for the use of visual analytics approaches to provide comparative assessment of arsenic in various foods. The topics covered include (i) metabolism of arsenic in the human body; (ii) arsenic concentrations in various foods; (ii) factors affecting arsenic uptake in plants; (ii) introduction to visual analytics; and (iv) benefits of visual analytics for comparative assessment of arsenic concentration in foods. Visual analytics can provide an information superstructure of arsenic in various foods to permit insightful comparative risk assessment of the diverse and continually expanding data on arsenic in food groups in the context of country of study or origin, year of study, method of analysis and arsenic species.

AIM: Patients with pulmonary tuberculosis (TB) tends to have limited exercise tolerance and a significant disability affecting their activities of daily living. The importance of exercise in the management of these patients has not been well investigated. This study was designed to assess the cardiovascular fitness of patients with pulmonary TB using the six-minute walk test (6-MWT). METHOD: Sixty five consented patients with Pulmonary TB were consecutively recruited into the study. The patients performed 6-MWT over a 30 meter course on a level walkway at a speed as fast as they could. Data were obtained on participants’ physical characteristics, pre and post exercise blood pressure and heart rate, and maximum oxygen consumption. Data were analyzed using descriptive statistics of mean and standard deviation and paired t-test. RESULTS: The post walk test cardiovascular parameters were significantly higher than the resting cardiovascular parameters. The mean VO2 max and MET of the participants were 11.7±0.97 (ml O2kg -1min-1) and 3.35±0.28 (mL/Kg) respectively. The means 6-MWT distance for male and female participants were 502.0±43.0m 481.7±68.3m respectively. CONCLUSION: The result implies that the 6-MWT is capable of evoking a significant cardiovascular change among patients with pulmonary TB. The 6-MWT may be useful in the assessment of functional capacity of patients with pulmonary TB. [TAF Prev Med Bull 2010; 9(2.000): 99-106]

This article reports on the level of toxic trace metals (Cd, Pb, Mn, Zn, Cu and Ni) in surface water and sediment along the Blaauwbankspruit in the West Rand District of South Africa. This spruit serves as receiving channel of wastewaters from sewage treatment plant and a gold mine. Some physical and chemical influences of released wastewater on the quality of the surface water, which is utilized for agricultural purposes was studied. Total trace metals in water and sediment samples were digested using mineral acid and then analyzed by Inductively Coupled Plasma-Atomic Emission Spectrometry. The mean concentrations of analyzed trace metals in water samples ranged from trace – 0.05, trace –0.11, 4.35 – 942.2, 0.10 – 0.41, 0.08 – 0.88 and 0.15 – 0.42 mg/l for Cd, Pb, Mn, Zn, Ni and Cu, respectively. The mean levels of trace metals in sediment samples also ranged between trace – 0.12,trace – 0.38, 12.3 – 2957.2, 0.13 – 2.57, 0.39 – 1.96 and 0.18 – 2.84 mg/g, respectively, in the above metallic order. Higher metallic load in sediments, compared to those in water samples were obtained. Safety limits, specified by the Department of Water Affairs and Forestry for the use of water for domestic and irrigational purposes were exceeded in many samples. This further highlights the serious concern regarding the use of contaminated surface water. In addition, higher values of determinants obtained from sampling points close to the wastewater treatment plant and the mine exit channels strongly revealed their influence on the general quality of the stream. Detection of metals such as cadmium and lead above acceptable limits has dire consequences across the food chain.

Groundwater (well water) from a residential area within the vicinity of an industrial estate in Lagos, Nigeria were sampled and analysed by Flame Atomic Absorption Spectroscopy for their heavy metals content. This was with a view of assessing the quality of the water, which was being used for domestic activities, especially, drinking usually without treatment. Total trace metal determination by mineral acid digestion of water samples was applied. This method proved to be better than an extractive concentration technique in the quality assurance protocols with the recovery range being 90.7 ± 0.006–97.6 ± 0.003%. Mean concentration of trace metals in water samples ranged from Fe: 0.05–0.47 mg l−1; Al: 0.1–1.54 mg l−1; Cu: 0.14–1.39 mg l−1; Zn: 0.04–0.43 mg l−1; Cd: trace–0.02 mg l−1; Pb: trace–0.03 mg l−1, Mn: 0.01–0.18 mg l−1 and Ni: 0.02–0.11 mg l−1. Physical parameters of water samples examined were within the drinking water safety limits except for conductivity. Results generally indicate the presence of heavy metal constituents in groundwater samples. Detection of metals such as cadmium and lead which have serious health implications above WHO and USEPA limits in drinking water gives cause for concern.

The concentration of trace metals (Cd, Cu, Pb and Zn) in a total of 144 samples of grass, soil and lower animal (earthworm, Lybrodrilus violaceous) were collected and analysed for their metallic content. Levels of cadmium ranged from 0.01-0.07 microg g(-1); 0.01-0.12 microg g(-1) and from trace-0.05 microg g(-1) dry weight for plant, soil and animal samples respectively. Mean concentration of copper ranged 0.10-1.48 microg g(-1); 0.10-2.90 microg g(-1) and 0.01-0.08 microg g(-1) for samples in similar order as above. The levels of Pb varied from 0.01-0.14 microg g(-1); 0.02-0.23 microg g(-1) and from trace-0.07 microg (g-1) while that of Zn ranged from 0.19-1.80 microg g(-1); 0.51-3.35 microg g(-1) and 0.01-0.08 microg g(-1) also in the same order of samples as mentioned above. Levels of metals in soil samples were higher than the background levels with the exception of Zn but lower than European Union (EU) limits. The results generally revealed the presence of metals in plant and animal samples and metal dynamics up the food chain is highly possible. Acceptable recoveries of the spiking experiment validate the experimental protocol.

Persistent organochlorine pesticides (OCPs) such as DDT and its metabolites (DDDs and DDEs), chlordane, hexachlorobenzene (HCB), heptachlor and endosulfan were determined in drinking-, ground-, surface- and marine waters from the Eastern Cape Province of South Africa. Percentage recoveries of the OCPs from spiked river water ranged from 71.03 ± 8.15% (dieldrin) to 101.25 ± 2.17% (α-BHC). The levels of OCPs ranged from 5.5 ng/L (2,4-DDD) to 160 ng/L (HCB) in the water samples. Some endocrine disrupting OCPs such as DDT, DDE, heptachlor, endosulfan and chlordane were detected.

This study reports the level of total petroleum hydrocarbons (TPHs) and trace metals in dusts from some petroleum handling facilities (gasoline stations), selected high traffic density roads and residential areas within the Tshwane Metropolitan area in South Africa. Total petroleum hydrocarbons in dust samples were extracted using soxhlet extraction and isolated gravimetrically after column cleanup, while total trace metals in dust samples were digested using mineral acid digestion and analyzed using atomic absorption spectrometry (AAS). The mean TPH level from the residential sites ranged from 206 +/- 20.3-300 +/- 36.4 microg g(-1) while those from gasoline stations and high traffic density roads varied between 562 +/- 43.9-340 +/- 62.6 microg g(-1) and 404 +/- 32.7-852 +/- 55.4 microg g(-1) respectively. Mean concentrations of analyzed trace metals at residential areas ranged from 0.04 +/- 0.02-0.07 +/- 0.03 microg g(-1); ND; 0.21 +/- 0.01-0.34 +/- 0.02 microg g(-1); 0.66 +/- 0.06-2.11 +/- 0.82 microg g(-1); 18.7 +/- 0.86-33.4 +/- 0.83 microg g(-1) and 0.07 +/- 0.04-0.23 +/- 0.01 microg g(-1) for Cd, Pb, Cu, Zn, Mn and Cr respectively. Mean levels from gasoline stations ranged between 0.05 +/- 0.02-0.17 +/- 0.07; 0.08 +/- 0.02-0.12 +/- 0.04; 0.21 +/- 0.04-4.34 +/- 0.60; 7.44 +/- 0.40-13.0 +/- 0.56; 23.36 +/- 4.37-131 +/- 10.5 and 0.05 +/- 0.02-0.17 +/- 0.05 microg g(-1) while those from high traffic density roads ranged from 0.07 +/- 0.04-0.10 +/- 0.04; ND-0.30 +/- 0.05; 0.67 +/- 0.05-3.80 +/- 0.82; 2.40 +/- 0.25-10.6 +/- 0.96; 19.8 +/- 1.03-108 +/- 4.44 and 0.06 +/- 0.02-0.12 +/- 0.04 microg g(-1) also in the above metal order. Contamination by TPH and trace metals both at gasoline stations and high traffic density roads is revealed by their significantly higher values compared to those of residential areas.

Biomasses of five fungi species ( Aspergillus niger , Penicillium austurianum, Saccharomyces cerevisiae, Mucor arcindloides and Trichoderma reesi were evaluated for their uptake of lead ion from aqueous solution using batch systems. Both dead and live fungal biomasses were comparatively studied for their adsorption efficiencies. The effect of pH as one of the primary factors that influences sorption efficiency of metal ions in solution was also studied. Modification of the fungal biomass with the least sorption capacity was carried out using a four-step procedure. Three different modifying agents under the optimised experimental conditions were used. The percentage uptake of lead ion by fungi species ranged from: Aspergillus niger : 6.71-64.95% and 66.91-95.27%; Penicillium austurianum : 44.47-98.85% and 75.57-94.21%; Saccharomyces cerevisiae : 52.61-88.68% and 61.20-89.95%; Mucor arcindloides : 83.78-93.13% and 62.91-97.65% and Trichoderma reesi : 52.52-80.70% and 35.31-88.13% for dead and live biomass respectively. The influence of pH on metal uptake was evaluated at pH of 2, 4, 6 and 7. A regular pattern of sorption efficiency among the dead fungi species with respect to pH was observed and the % adsorption decreased in the order pH 7 > 2 > 6 > 4 with the exception of Mucor (pH 7 > 2 > 4 > 6). Modified biomass of Aspergillus niger with oxalic acid, malic acid and ethylenediamine tetraacetic acid (EDTA) recorded 92.84%, 48.11% and 39.83% uptake of Pb respectively which correspond to 69.65%, 41.23% and 29.25% increase when compared to 28.18% of the unmodified biomass. These quantitative adsorptions demonstrate the potential application of modified biomass for the removal of Pb ion from aqueous solution.

Studies into social inequalities in health tend to focus more on parental socio-economic status (SES) as it affects the children. We aimed to test the hypothesis that socio-economic inequalities would not affect the casual blood pressure among Nigerian adults.Resting blood pressure (BP) and pulse rate of 1067 sedentary adults were measured. Rate pressure product and pulse pressure were later calculated. Second, a structured questionnaire, which objectively assessed the SES of the subjects, was administered. Subsequently, a self-rating SES ladder was employed to classify the subjects into different socio-economic groups. This was used as a check for the structured questionnaire. A Pearson product correlation coefficient comparing the two outcome measures revealed a high correlation (r=0.951, P0.01). Socio-economic status was found to have an inverse significant (P0.05) effect on systolic pressure, heart rate and pulse pressure. The 95th centile blood pressure obtained was 154/91 mmHg.Low SES is associated with development of hypertension among the Nigerian adults.

This paper presents an assessment of the level of vanadium in foods (Plantain, Musa spp; Yam, Discorea rotundata; and Maize, Zea mays) from ten popular market places in Lagos metropolis, Nigeria. Total acid leaching digestion method was employed and determination was by Flame Atomic Absorption Spectrophotometry. The concentration of the metal obtained ranged from 0.01 ± 0.001 (M 3 ) - 0.62 ± 0.002 (M 2 ) for Musa spp; 0.02 ± 0.001 (M 3 , M 5 , M 9 ) - 0.41 ± 0.002 (M 3 ) for Discorea rotundata; and 0.01 ± 0.001 (M 1 ) - 0.35 ± 0.001 (M 6 ) for Zea mays. The overall mean concentrations of the metal were 0.19, 0.13 and 0.09mg g -1 in the same food order. The quality assurance of the analytical protocol was in the range of 91.5 - 98.1 % with C.V. of between 1.5 – 3.4%, which was adjudged acceptable for the analytical protocol. Vanadium was detected in all analysed foods with some elevated concentrations. Key Words: Vanadium, foods, AAS, coal, city, terminals African Journal of Science and Technology Vol.5(1) 2004: 15-21

Levels of Cd, Hg and Zn in some surface waters from the Eastern Cape Province, South Africa, Water SA, 29 (4) 2003, p.377

Persistent organochlorines such as SDDT, chlordane, hexachlorobenzene (HCB), heptachlor and endosulfan were determined in water and sediment samples of freshwater systems in the Eastern Cape Province of South Africa that receive runoff from agricultural lands and effluents from industries. The organochlorine pesticides (OCPs) in water and sediments were determined by liquid/liquid extraction and Soxhlet extraction methods, respectively. Percentage recoveries ranged from 71.03 + 8.15 % (dieldrin) to 101.25 + 2.17 % (a-BHC) in water and from 88.22 + 7.85 % (endrin) to 109.63 + 5.10 (b-BHC) in sediment. The OCP levels ranged from trace (2,4'-DDD) to 450 + 0.0002 ng/ℓ (b-BHC) in water samples and from trace (aldrin and 2,4'-DDD) to 184 x 103 + 0.7 ng/kg (b-BHC) in sediments for triplicate analyses. Some endocrinedisrupting OCPs such as 2,4'-DDT, 4,4'-DDT, 2,4'-DDE, heptachlor, endosulfan and the chlordanes were detected. Water SA Vol.29(3) 2003: 323-330

Different extraction methods were evaluated for the determination of fifteen organochlorine pesticides (OCPs) in water and sediments. Liquid-liquid extraction (LLE) was evaluated for the pesticides analyses in water while Soxhlet extraction (SE) and microwave assisted extraction (MAE) methods were compared in sediment. Of all the extracting solvents used, dichloromethane gave the best results. Percentage recoveries ranged from 71.03 +/- 8.15 (dieldrin) to 101.25 +/- 2.17% [a-benzenehexachloride (alpha-BHC)] in water with LLE. In sediments the percentage recoveries with Soxhlet extraction method varied between 88.22 +/- 7.85 (endrin) and 109.63 +/- 5.10% (beta-BHC) and ranged from 74.11 +/- 9.82 (2,4 DDT) to 97.50 +/- 4.56% (alpha-BHC) with MAE. The limits of detection for the OCPs ranged from 5.5 to 20.6 ng/l and between 0.6 and 2.1 ng/g. respectively. The LLE and the SE methods were applied to water and sediments samples, respectively, from marine and freshwater sources in the Eastern Cape Province of South Africa that receive runoffs from agricultural lands and effluents from industries. The levels of OCPs ranged from 5.5 (2,4-DDD) to 450 +/- 0.10 ng/l (beta-BHC) in water samples and from 0.6 (aldrin and 2,4-DDD) to 184 +/- 0.12 ng/g (beta-BHC) in sediments for triplicate analyses. Some endocrine disrupting OCPs such as DDT, DDE, heptachlor, endosulphan and the chlordanes were detected.

Andreas N Mbah,1,2 Ousman Mahmud,1 Omotayo R Awofolu,2 Raphael D Isokpehi11Center for Bioinformatics and Computational Biology, Department of Biology, Jackson State University, Jackson, MS, USA; 2Department of Environmental Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Pretoria, South AfricaBackground: Human schistosomiasis is a freshwater snail-transmitted disease caused by parasitic flatworms of the Schistosoma genus. Schistosoma haematobium, Schistosoma mansoni, and Schistosoma japonicum are the three major species infecting humans. These parasites undergo a complex developmental life cycle, in which they encounter a plethora of environmental signals. The presence of genes encoding the universal stress protein (USP) domain in the genomes of Schistosoma spp. suggests these flatworms are equipped to respond to unfavorable conditions. Though data on gene expression is available for USP genes, their biochemical and environmental regulation are incompletely understood. The identification of additional regulatory molecules for Schistosoma. USPs, which may be present in the human, snail, or water environments, could also be useful for schistosomiasis interventions.Methods: We developed a protocol that includes a visual analytics stage to facilitate integration, visualization, and decision making, from the results of sequence analyses and data collection on a set of 13 USPs from S. mansoni and S. japonicum.Results: Multiple sequence alignment identified conserved sites that could be key residues regulating the function of USPs of the Schistosoma spp. Based on the consistency and completeness of sequence annotation, we prioritized for further research the gene for a 184-amino-acid-long USP that is present in the genomes of the three human-infecting Schistosoma spp. Calcium, zinc, and magnesium ions were predicted to interact with the protein product of the gene.Conclusion: Given that the initial effects of praziquantel on schistosomes include the influx of calcium ions, additional investigations are required to (1) functionally characterize the interactions of calcium ions with the amino acid residues of Schistosoma USPs; and (2) determine the transcriptional response of Schistosoma. USP genes to praziquantel. The data sets produced, and the visual analytics views that were developed, can be easily reused to develop new hypotheses.Keywords: ATP binding protein, calcium, functional sites, praziquantel, Schistosoma, schistosomiasis