Assessing the levels of Pb, Cd, Zn and Cu in biscuits and home-made snacks obtained from vendors in two tertiary institutions in Lagos, Nigeria

The modern day busy schedule of an average individual in Nigeria has made the consumption of snacks inevitable. This study assessed the concentrations of Zn, Cu, Pb and Cd in some common snacks sold in two tertiary institutions in Lagos, Nigeria, using Perkin AAS Elmer model 460. The mean levels of Zn, Cu, Pb and Cd found in plantain chips obtained from the University of Lagos main campus were 2.15 ± 0.13, 0.27 ± 0.03, 0.83 ± 0.04 and 0.10 ± 0.03 mg/kg respectively, while the mean levels of the same metals found in plantain chips obtained from Yaba College of Technology were 1.77 ± 0.57, 0.11 ± 0.04, 1.23 ± 0.61 and 0.08 ± 0.06 mg/kg respectively. Independent-samples t-test analysis revealed that the differences between the mean metal levels in snacks obtained from the two institutions were not significant (P > 0.05). Though the levels of most metals in snacks obtained from the two institutions were within the upper limits of the range specified by the World Health Organization, the consumption of snacks with such metal loads over a long period of time may result in metal accumulation in the body beyond tolerable limit. These findings may be a reflection of what obtains in other educational institutions in the country. The authorities of tertiary institutions and other levels of education in Nigeria are therefore called upon to strengthen and widen their internal control mechanisms to guarantee the quality and safety of snacks sold to students and other people on their campuses.Keywords: Contaminants, Contamination, FAO/WHO, food, snacks, campuse

Physicochemical Quality and Genotoxic Potential of Wastewater Generated by Canteen Complex

Canteens generate high volumes of wastewater that should constantly be subjected to physicochemical and genotoxicity screening. In this study, the wastewater generated by a canteen complex was screened for physicochemical properties and genotoxic potential using standard procedures and Allium cepa chromosome assay. Results showed that the wastewater had total suspended solids, total dissolved solids, and total hardness concentrations of 120.70 mg/l, 554.50 mg/l, and 500.00 mg/l, respectively. The chloride concentration of the wastewater (7873.60 mg/l) was much higher than the recommended limit of 250 mg/l. The wastewater inhibited root growth in A. cepa at 0.1%, 1%, 10%, 25%, 50%, and 100% concentrations but promoted root growth at 2% and 5% concentrations. The wastewater was highly mitodepressive, with mitotic inhibition generally increasing with rising concentrations. The major chromosomal aberrations observed in A. cepa exposed to different concentrations of canteen wastewater were vagrant, sticky, and bridged chromosomes. No chromosomal aberration was observed in onion roots exposed to water (control). The differences in total chromosomal aberrations across wastewater concentrations were not statistically significant (P > 0.05). In view of these results, the practice of discharging untreated canteen wastewater into drainage canals may not be environmentally sustainable

Comparative physicochemical and genotoxicity assessments of textile mill company effluent and local tie-and-dye textile wastewater

The textile industry has become indispensable in view of its basic and social importance to human life, but its environmental impact has continued to be a subject of concern. The objectives of the present study were to assess and compare the physico-chemical and genotoxicity properties of a corporate textile mill effluent and the wastewater generated by a local Tie-and-dye (Adire) business in Western Nigeria. While the Allium cepa assay was used to assess genotoxicity, standard APHA and other procedures were used to analyse the physico-chemicalproperties. Results showed that many physicochemical qualities of the two effluent types were higher than the recommended limits. The root growth and mitotic inhibition potential of the two effluent types increased with rising effluent concentrations and period of exposure. The chromosome aberrations induced by the two effluent types were binucleated, attached, vagrant, sticky, and bridged chromosomes. Independent samples t-test analyses revealed that the differences between the two effluent types were only marginal and not significant (P > 0.05). This implies that the textile mill company whose effluent was used for this study did not subject its effluent to treatment before discharging, and if it did, the treatment was grossly inadequate. Governments at all levels in Nigeria, and other countries in which similar results may be obtained, are called upon to reinvigorate their regulatory agencies to enable them to discharge their oversight functions effectively.Keywords: Chromosome, contaminants, environment, effluents, Nigeria, textil

Air quality management in Botswana

This paper examines air pollution situation and the history of air quality management in Botswana. The current air quality management in Botswana is still largely underpinned by the Atmospheric Pollution Prevention Act of 1971, supplemented by the more recently enacted legislations such as the Environmental Impact Assessment (EIA) Act of 2010 and the Ambient Air Quality - Limits for Common Pollutants of 2012 published by the Botswana Bureau of Standards. Though commendable efforts have been made towardlegislating against air and other forms of pollution, these have not yielded expected results in view of the prevailing levels of air pollutants like sulphur dioxide and fine particulate matters in the country’s atmospheric environment. Legislation as a sole measure may not be effective in tackling this challenge. Rather, government should also address some root-causes of the problem by making policies and programmes that will reduce unemployment and increase the earning capacity of citizenry. This will, among other things, effectively check poverty-induced biomass burning in the country. The paper looks at some other challenges of air pollution management and suggestions are made to tackle the identified problems

Evaluation of the Cytogenotoxic Effects of Emulsifiable Concentrate form of Amitraz Pesticide on Allium cepa L

The cytogenotoxic effects of emulsifiable concentrate of amitraz pesticides was evaluated using Allium cepa L. test. The root meristems of A. cepa L. were treated with five concentrations (1%, 5%, 10%, 20% and 40%) of the chemical pesticide at 48 h for cytogenetic analyses and 96 h for root length inhibition. Pesticide doses affected root length significantly (P<0.05) at 5% to 40%; with 50% effective concentration (EC50) value of 18% while there was no significant difference between control and 1% (p>0.05). The mean root length of the treated A. cepa for Amitraz pesticides in all concentrations was lower compared to the control showing the obvious mitodepressive effects of amitraz pesticides. A dose dependent reduction in the total mitotic dividing cells and mitotic index was observed in A. cepa treated with the pesticides. The values of mitotic index obtained for amitraz pesticides at 5% (5.20), 10% (4.0), 20% (2.30) and 40% (0.80) were lower than half of the negative control (7.25), which reflect its cytotoxicity. All the concentrations of the pesticides used in the present study induced important abnormalities during mitotic division. These aberrations were: chromosome stickiness, disturbed spindle, anaphase and telophase bridges, chromosome fragments, laggard chromosomes, and c- Mitosis. The highest abnormality number was observed in the root tips of Allium cepa (5%) while the least was at 40%. Frequencies of chromosome abnormalities were low at 20% and 40% concentration because of damaged cell and lower cell divisions. The present study, showed the inhibition of growth and induction of chromosomal aberrations by amitraz, this suggest their capability in inducing cytotoxicity and genome instabilityKeywords: Allium cepa, chromosomes, amitraz pesticides, aberrations, mitotic inde

New-Onset Seizures in HIV Patients on Antiretroviral Therapy at a Tertiary Centre in South-West, Nigeria

Background: Seizures are associated with neurological manifestations of HIV. They may be the presenting symptom and can occur at any disease stage. Aim: To determine the frequency and clinical aspects of new-onset seizures in patients with human immunodeficiency virus (HIV) infection. Methods: A study of an HIV-infected patient cohort on highly active anti-retroviral therapy (HAART) in the out-patients clinic of the Lagos state university teaching hospital, Nigeria. In a cross-sectional design, 308 HIV infected patients were recruited over a period of 1 year. Cases with a first seizure during this period were further examined. Details of demographic data, the first seizure date, seizure characteristics, neurologic complications and CD4 count at the time of the seizure were documented. Results: A total of 20 (6.5%) had new-onset seizures during the study period. 6/20 (30%) were males and 14/20 (70%), females. Their ages ranged between 22 - 51 years with a mean of 34.2 ± 8.7 years. The seizure was focal in 2/20 (10%) of cases and generalised in 90% (18/20) of cases. A total of 13/20 (65%) had recurrence of their seizures. None of the cases had focal neurological deficit at the time of the first seizure. The mean CD4 count was 165.3 ± 145.7. The mean duration on HAART was 19.5 ± 12.7 months. Cases with CD4 counts ≤200 cells/mm3 constituted 70% (14/20) whilst those with CD4 counts >200 made up 30% (6/20) [p = 0.666]. Conclusions: Seizures remain a significant neurological manifestation of HIV infection and has a high recurrence rate. It occurs more commonly in the advanced stage with severe immune suppression and may be attributable to HIV encephalopathy. Early treatment would reduce the burden and improve patient’s quality of life

Seroprevalence of human T lymphotropic virus antibodies among healthy blood donors at a tertiary centre in Lagos, Nigeria

Introduction: Transmission of human T-lymphotropic viruses (HTLV) occurs from mother to child, by sexual contact and blood transfusion. Presently, in most centres in Nigeria, there is no routine pre-transfusion screening for HTLV. The study aims to determine the prevalence of HTLV-1 and HTLV-2 among healthy blood donors at a tertiary centre in Lagos. Methods: A cross-sectional study was carried out at the blood donor clinic of the Lagos State University Teaching Hospital (LASUTH), Ikeja. About 5mls of venous blood was collected from each subject into a sterile plain bottle after obtaining subject's consent. The serum separated and stored at -200C. Sera were assayed for HTLV by an enzyme-linked immunoassay (ELISA) for the determination of antibodies to HTLV 1 and HTLV -2. Western blot confirmatory testing was done on reactive samples. All donors were also screened for HIV, HBsAg and HCV by rapid kits. Results: The seroprevalence of HTLV -1 by ELISA was 1.0% and 0.5% by Western Blot among blood donors. A total of 210 healthy blood donors were enrolled. Only 2 (1.0%) blood donors were repeatedly reactive with ELISA test. On confirmatory testing with Western Blot, 1 (0.5%) blood donor was positive for HTLV. All the healthy blood donors were negative for HIV, HbsAg and HCV. None of the 210 blood donors had been previously transfused; as such no association could be established between transfusion history and HTLV positivity among the blood donors. Conclusion: The seroprevalence of HTLV in this environment is low among healthy blood donors

DEVELOPMENT OF AN ARDUINO-BASED OBSTACLE AVOIDANCE ROBOTIC SYSTEM FOR AN UNMANNED VEHICLE

The use of autonomous systems in the world to perform relevant and delicate task is fast growing. However, its application in various fields cannot be over emphasized. This paper presents an obstacle detection and avoidance system for an unmanned Lawnmower. The system consists of two (Infrared and Ultrasonic) sensors, an Arduino microcontroller and a gear DC motor. The ultrasonic and infrared sensors are implemented to detect obstacles on the robot’s path by sending signals to an interfaced microcontroller. The micro-controller redirects the robot to move in an alternate direction by actuating the motorsin order to avoid the detected obstacle. The performance evaluation of the system indicates an accuracy of 85% and 0.15 probability of failure respectively. In conclusion, an obstacle detection circuit was successfully implemented using infrared and ultrasonic sensors modules which were placed at the front of the robot to throw both light and sound waves at any obstacle and when a reflection is received, a low output is sent to the Arduino microcontroller which interprets the output and makes the robot to stop

Seroprevalence of human T lymphotropic virus antibodies among healthy blood donors at a tertiary centre in Lagos, Nigeria

Introduction: Transmission of human T-lymphotropic viruses (HTLV) occurs from mother to child, by sexual contact and blood transfusion. Presently, in most centres in Nigeria, there is no routine  pre-transfusion screening for HTLV. The study aims to determine the prevalence of HTLV- 1 and HTLV-2 among healthy blood donors at a tertiary centre in Lagos.Methods: A cross-sectional study was carried out at the blood donor clinic of the Lagos State University Teaching Hospital (LASUTH), Ikeja. About 5mls of venous blood was collected from each subject into a  sterile plain bottle after obtaining subject's consent. The serum separated and stored at -200C. Sera were assayed for HTLV by an enzyme-linked immunoassay (ELISA) for the determination of antibodies to HTLV 1 and HTLV -2. Western blot confirmatory testing was done on reactive samples. All donors were also screened for HIV, HBsAg and HCV by rapid kits. Results: The seroprevalence of HTLV -1 by ELISA was 1.0% and 0.5% by Western Blot among blood donors. A total of 210 healthy blood donors were enrolled. Only 2 (1.0%) blood donors were repeatedly reactive with ELISA test. On confirmatory testing with Western Blot, 1 (0.5%) blood donor was positive for HTLV. All the healthy blood donors were negative for HIV, HbsAg and HCV. None of the 210 blood donors had been previously transfused; as such no association could be established between transfusion history and HTLV positivity among the blood donors. Conclusion: The seroprevalence of HTLV in this environment is low among healthy blood donors.Key words: Seroprevalence, HTLV, healthy blood donors, Nigeri

Mean platelet volume and platelet counts in type 2 Diabetes: Mellitus on treatment and non-diabetic mellitus controls in Lagos, Nigeria

Introduction: The Mean platelet volume and platelet counts are indicators of thrombotic potentials, and risk factors for microvascular complications in diabetics. This study aimed to establish variations in platelet counts and mean platelet volume in type 2 diabetic patients on treatment and non-diabetic controls. Methods: This was an unmatched case-control study involving 200 participants consisting of 100 diabetics and 100 non-diabetic controls. Four and half milliliters of blood was collected from diabetics and non diabetic controls into EDTA anticoagulant tubes. Full blood count was performed using the Sysmex KN-21N, (manufactured by Sysmex corporation Kobe, Japan) a three- part auto analyzer able to run 19 parameters per sample including platelet counts and mean platelet volume. Results: The mean fasting blood sugar for the diabetics was 147.85±72.54 mg/dl and the controls 95.20±30.10 mg/dl. The mean platelet count for the diabetics was 235.29±76.81*109/L and controls, 211.32±66.44*109/L. The mean platelet volume, for the diabetics was 8.69±0.67 fl and the controls, 8.91±0.80 fl. There was a statistically significant difference in platelet counts of diabetics and healthy controls p =0.038 while none existed between the mean platelet volume in diabetics and healthy controls p=0.593. Conclusion: This study revealed a higher mean platelet count for diabetics on treatment than for non diabetic controls while mean platelet volume was lower in cases than controls. However, both parameters in diabetics on treatment were within the normal reference range for healthy individuals