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Abstract

The ingestion of aluminum from food containers such as cookware, cans, utensils and wrappings and its subsequent release into the environment is a growing public health concern. Aluminum is widely used in manufacturing cookware due to its malleability, high heat conductivity, light weight, durability, availability and affordability. This paper therefore gives a review of most relevant literatures on the benefits and risks of the various types of aluminum cookware in use, the composition and the public health effects of aluminum ingestion. Studies that reported the leaching of aluminum from cookware into food and environmental effects of aluminum leaching were also reviewed. In the developing countries, aluminum cookwares are produced from scrap metals and has been reported to leach harmful substances including heavy metals such as: nickel, arsenic, copper, cadmium, lead, and aluminum into cooked food. Several factors have been reported to increase the rate of leaching of metals from aluminum cookwares. Exposure to metals from aluminum cookware and the public health effects have not been well studied, hence, our recommendation for more studies to elucidate the health effect of this practice. This review also presents measures that can limit exposure to the risks that may arise from the use of aluminum cookware.

Abstract

The volume of pharmaceuticals discharged into the environment increases daily as a consequence of human life. In the present study, the seasonal variation of ibuprofen in sediment, biota, water, and their exposure risk were investigated in River Owena and Ogbese, Nigeria. The high-performance liquid chromatography coupled to a mass spectrometer (HPLC-MS/MS) was used to analyze the samples after clean up and pre-concentration by solid-phase extraction. The mean concentration of IBU in the samples spanned a range of 1.75 - 2.75 μg/g in sediment, 0.01 – 15.00 μg/g in fish, and 0.00002 – 0.005 μg/ml in water. The measurement of IBU in the sediment and water was significantly elevated in the dry season than the wet season, whereas the opposite was the case in biota. There was a significant interaction between season, media, and rivers with respect to IBU occurrence in the sampled rivers. The calculated bio-water accumulation factor (BWAF) was as high as 750,000 μg/g in fish, proving IBU is extremely bio-accumulative. The ecotoxicological risk assessment for average and worst possible outcome showed that the risk quotient (RQ) for IBU present in the water was sufficient to cause toxicity to fish in both freshwater bodies. The potential bioavailability of IBU to aquatic fauna for prolonged periods spanning several months can result in its circling back into the food web afterward. The baseline info provided by this study in these freshwaters may provide valuable information for the implementation of safety limits for the management of IBU influx into the environment.

Abstract

The combination of antiretroviral (ARV) drugs: lamivudine, tenofovir disoproxil fumarate (TDF) and efavirenz is among the preferred first-line regimens for adolescents and adults infected with HIV. However, knowledge on in vivo genetic and reproductive toxicity of each of these drugs and their combination is limited. We evaluated the genotoxicity of lamivudine, TDF, efavirenz and their combination utilizing the mouse micronucleus (MN) and sperm morphology tests. Histopathological analysis of the testes of exposed mice was also carried out. 0.016, 0.032, 0.064 and 0.129 mg/kg bwt of lamivudine, TDF and the combination; and 0.032, 0.064, 0.129 and 0.259 mg/kg bwt of efavirenz corresponding to 0.125, 0.250, 0.500 and 1.000 x the human therapeutic daily dose (HTD) of each of the ARVs and their combinations were administered to mice for 5 consecutive days. Data on MN showed a significant increase (p ---lt--- 0.05) across the tested doses of TDF, efavirenz and the combination, with the combination inducing lower frequency of MN than TDF and efavirenz. Lamivudine did not evoke significant induction of MN. Significant increase in frequency of abnormal sperm cells were observed in the tested samples, however, the combination induced the highest number of abnormal spermatozoa. The ARVs and their combination induced pathological lesions such as vacuolation and necrosis in mice testes. These findings suggest that the individual ARVs and their combination are potentially capable of activating genetic alterations in the bone marrow and germ cells of male mice thereby raising concern for long term use by HIV patients.

Abstract

This paper assessed in-vehicle and ambient pollution levels from vehicles along Ilorin-Lagos highway covering three distinct 3-hour periods (morning, afternoon and evening) of the day (from 7.30 am to 6.30 pm) along with reported health challenges at six (6) settlements (SP1-SP6) that covered four (4) states. In the case of ambient pollution, Gilair-3 air sampler (GAS) was used to measure sulphur (iv) oxide, (SO2) while ALTAIR 5x Multi-gas Detector (AMD) was used to measure both carbon (ii) oxide, (CO) and sulphur (iv) oxide, (SO2) for all scenarios. Vehicular volume was manually conducted to determine the number of vehicles. Questionnaire was used to assess information on the health challenges faced by the commuters. The concentrations of SO2 ranged from 0.142 - 0.550 ppm (ambient) and 0.037 - 0.097 ppm (in vehicle) using AMD and GAS respectively while CO concentration was between 2.289 - 18.055 ppm using AMD. The results for the in- vehicular pollution revealed that the concentration levels obtained for CO and SO2 inside the vehicles were 6.32 ppm and 0.126 ppm under opened-window condition and 9.53 ppm and 0.274 ppm under closed-window condition respectively (without air condition). The SO2 concentrations obtained from both ambient and in-vehicle were found to be much higher when compared with the FEPA standards; SO2 (0.01 – 0.1 ppm), USEPA standards; SO2 (0.075 ppm) while the CO level obtained from in-vehicle under the two scenarios (opened and closed windows) were below the limit of NESREA standards (10 – 20 ppm) and USEPA standards (35 ppm). Having noticed that these pollutants act under different environmental conditions, the work established statistical evidence that traffic volume affected the pollutants concentrations at most of the sampling points and that the higher the traffic, the higher the emissions and the more the risk of health challenges.

Abstract

The present work examines the influence of the leaching conditions on the release of various chemical elements from a cementitious material obtained by solidification of an industrial waste rejection of Algeria. Toxicity Characteristic Leaching Procedure (TCLP), X-ray diffraction (XRD) and Scanning electron microscopy coupled with energy dispersive X-ray microanalysis SEM-EDX analyses were employed to characterize the waste and the stabilized/solidified materials. Than several formulations were prepared with different percent of waste ranging from 0 % to 30 %. To evaluate the influence of leaching conditions on the release of chemical ions (Zn2+, Pb2+, Cl-, Mg2+, Ca2+, Na+, K+ and SO4 2−) contained in the stabilized and solidified materials, the Acid Neutralization Capacity (ANC), the Pore Water (PW) and Monolith Leaching Tests (MLT) have been carried out. The leaching tests (ANC, PW and MLT) have shown a low metal leachability. However, the lowest released amount was observed for the MLT.

Abstract

This study was conducted to identify the most deleterious nonsynonymous single nucleotide polymorphisms (nsSNPs) in the ovalbumin gene family, including OVALX, OVALY, and OVAL genes, which are involved in the synthesis of the most important components in the chickens’ eggs using a comprehensive in silico approach. Ten different computational servers were utilized to prioritize the possible deleterious effects of the retrieved nsSNPs in terms of structure, function, and stability. Results indicated entirely damaging effects of H365P in OVALX, I167T in OVALY, and V209G, L231P, F307C, and S317P in OVAL proteins. Further prediction tools showed that all of these deleterious nsSNPs were positioned in variable locations within several α-helix motifs in all studied ovalbumin proteins. Furthermore, all witnessed nsSNPs were predicted to be resided in the receptors binding sites, signifying remarkable involvement of such nsSNPs in damaging of the altered proteins. In conclusion, the present study provides the first inclusive data with regard to the most deleterious nsSNPs in OVALX, OVALY and OVAL genes in chickens. The present bioinformatics data may be useful for breeders who intend to raise chickens for egg production, in such a way the presence of any of these deleterious nsSNPs in any selected breed may possess several damaging effects on the egg components, which may impair egg production. Therefore, it can be stated that breeders have to confirm the absence of any of these deleterious nsSNPs before being proceeded further for large-scale egg-production purposes.

Abstract

Methylxanthines such as caffeine, theophylline, theobromine are significant and widespread psychoactive substances. We developed the isocratic method with optimum composition of the mobile phase 90 % water: 10 % acetonitrile and confirmed repeatability of retention times and peak areas. The developed HPLC method was applied to determine the content of methylxanthines in selected types of black and green teas available on the market. Of the black teas (tea bags), the highest concentration of theobromine was found in Ceylon tea (18.98 mg.L−1). The highest concentration of caffeine was in a cup of Earl Gray tea (254.09 mg.L−1). Among loose black teas, the highest content of both theobromine and caffeine was found in Pu Erh Superior tea, where the theobromine content was 24.62 mg.L−1 and the caffeine content was 520.67 mg.L−1. Of green powder teas, highest caffeine content (306.46 mg.L−1) was in Shizuoka Matcha Premium and the highest content of theobromine (8.45 mg.L−1) was found in GABA Midori. From the loose green tea, the highest concentration of theobromine (12.85 mg.L−1) was in Lung Ching West Lake. The highest caffeine content (484.85 mg.L−1) was in Gyokuro Shizuoka Premium Tea. In both types of teas the amount of theobromine and caffeine was quantified, but the presence of theophylline was not proven. Data on contents of these metabolites in tea products are highly informative for consumers.

Abstract

Studies reveal that not up to 50% of earthworm species have been described in the world and the understanding of earthworm diversity is finite in most countries including Nigeria. The study was aimed at evaluating the diversity of earthworms and environmental factors affecting their abundance. Earthworms were collected from three (3) different sampling locations in Nnamdi Azikiwe University, Awka. Descriptive statistics and estimation of species abundance, dominance and diversity were used to analyze the data obtained from the study. From the study, four (4) species of earthworms were identified and recorded from the three sampling locations. Eudrilus eugeniae (54.9%) was the most abundant species followed by Hyperidrilus africanus (20.3%), Libyodrilus violaceous (19.6%) and Alma millsoni (6.3%) with the least abundant species. The result of the diversity indices showed Science village (1.13) as the most diverse habitat followed by Emelda hostel (0.86) and Boys’ hostel (0.84) with the least diversity of species. Soil pH ranged from 2.25 to 4.06 and total organic matter ranged from 14.10 to 16.36%. Soil temperature was uniform with an average value of 27°C for the three sampling locations. The soil moisture content ranged from 11.19 to 14.12%. The conductivity recorded the lowest value (25.60μS/cm) in Emelda Hostel and highest value (111.8 μS/cm) in Science village. The study provided understanding into the patterns of earthworm populations in Nnamdi Azikiwe University, Awka and the need for the conservation of earthworm diversity. Better understanding about habitat and living conditions of earthworms is required to provide suitable and enhanced production of vermicompost in different geographic conditions.

Abstract

Testing microbial quality of the harvested rainwater remains a challenge in many countries. The H2S test kit is a low-cost microbiological field-based test which can be used in areas where water testing facilities are limited. This study compares its efficiency with the standard indicators microorganisms in the detection of faecal contamination of rainwater in South Africa. A total of 88 rainwater samples were collected from various tanks in the Eastern Cape, South Africa over three months in 2016. The collected samples were analysed for faecal bacterial contamination using the H2S test kit, Colilert-18/Quanti-tray®/2000 and the membrane filtration technique for faecal coliforms (MFT). The correspondence rate of the H2S test kit with MFT was 88 %, while for the Colilert® it was 76 %. The H2S test kit confirmed faecal contamination when concentrations of standards indicators microorganisms were 5 most-probable number of cells/100 cm3 or higher. Overall, the best correspondence of the H2S test kit with Colilert® was observed at E. coli concentrations above 50 most-probable number of cells/100 cm3. Results of the H2S test kit correlated better with MTF, while the medium used has strongly influenced the enumeration of faecal contamination. Results point to strong effect of media used and revealed the need to calibrate the correspondence between the standard indicator microorganisms and the H2S test kit under local conditions for specific settings.

Abstract

In this treatise, we examined the activities of researchers of Nigeria descent in the frontier areas of nanoscience and nanotechnology, with a focus on green nanotechnology. The exploration of literature published by scholars were reviewed and compartmentalized on the basis of applications of the nanomaterials. It can be concluded that the level of activities in this area is expanding owing to the emergence of more published works since the beginning of 2010. However, in comparison with research outputs from other developing African countries such as South Africa and Egypt, activities in green nanotechnology are still at low ebb in Nigeria. Issues that are contributory to the slow pace were identified and appropriate solutions in terms of improved funding of education, enactment of national policy on nanotechnology, curriculum development, international cooperation as well as human resource development among others were discussed.