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Nov 2019 DOI 10.14302/issn.2637-6075.jpae-19-3074
This study was conducted to investigate the concentration of three heavy metals; iron, chromium and lead in surface water and plant (Sacciolepisafricana) tissues along the Epie creek. This was aimed at determining the heavy metal loading of surface waters and the extent of bioaccumulation in the most prevalent grass species found growing within the river course. Metals were determined using atomic absorption spectrophotometer. Result of water analysis recorded the least and most significant iron concentrations of 3.42 ± 0.06 mg/L and 12.06 ± 0.06 mg/L for Agudama and Edepie axis respectively. Contrastingly, water samples showed chromium and lead levels which were below their instrument measurable limits. Consequently, lead (Pb) and chromium (Cr) levels were within WHO permissible limits, while iron (Fe) exceeded regulatory standard for water samples collected from all field locations. Similarly, iron recorded elevated iron concentrations in plant (cupscale grass) with the least amount being revealed for Igbogene stem (196.63 ± 5.21 mg/kg), and the most concentration been reflected for Edepie root sample (9,423.17 ± 48.55 mg/kg). Even though iron levels prevalently exceeded recommended threshold in plants, the stem were mostly within limit for iron. The only grass sample depicting significant lead amount (0.34 mg/kg) was the stem section collected at Akenfa location. Evidently, metals were least stored in plant stems and most bioaccumulated in plant roots. Furthermore, Cr and Fe are the only significantly correlating metals in plants (r = 0.700, p < 0.01). Overall, the increasing level of Fe in the water environment is further indication of the impact of unregulated dumping of scraps and domestic waste along the creeks embankment.
Aug 2023 DOI 10.14302/issn.2639-3166.jar-23-4682
Objectives The solid-liquid separation (SLS) process generally separates solid and liquid fractions in wastewater and livestock manure. The solid-liquid separation process is an essential pretreatment step for the recycling and purification of pig manure. This study has assessed the separation and/or reduction efficiency by various SLS processes used in pig farms. Methods Seven types of SLS processes (centrifuge, centrifuge (+coagulation agent), belt press (+ coagulation agent), drum screen, inclined screen, vibration screen, and screw press) were used on 11 pig farms and conducted a comparative analysis. As for the sample in this study, the pig raw manure before treatment, the separated liquid and solid manure after treatment of the SLS process collected, respectively. These samples were provided for pH, EC(electrical conductivity) moisture content, CODMn, BOD5, TN, TP, K, TS, SS, NaCl, and heavy metals analysis. Results and Discussion The belt press (+coagulation agent) process had the highest TS and SS reduction rate of 78.8% and 96.9%, respectively. The highest removal efficiency of TN and TP was41.0% and 94.2% by belt press (+coagulation agent) and centrifuge (+coagulation agent),respectively. The belt press (+coagulation agent) removed 59.4% and 66.0% of BOD5 and CODMn,respectively. The Zn and Cu were removed 100% and 98.6% by centrifuge (+coagulation agent).However, the drum screen, inclined screen, vibration screen, screw press, and centrifuge showed lower removal efficiency of nutrient contents, solids, Zn, and Cu than centrifugal and belt press processes with chemical coagulation. Conclusions The centrifugal and belt press separation processes that used chemical coagulation showed much more removal efficiency of nutrient contents, solids, and metals like Zn and Cu. Although SLS with chemical coagulants is an effective pre-treatment process for liquid manure treatment and helps removal effect for suspended solids, nutrients, and heavy metals, further studies are needed on how it affects biological or chemical processing processes that are linked.
Aug 2020 DOI 10.14302/issn.2641-4538.jphi-20-3475
Effluents discharged from various industries contain heavy metals. They reach the environment and affect the quality of air, water and soil. Though they are needed in trace quantities for living organisms, they become toxic when they exceed the threshold concentrations. Hence the present study has been designed to test the efficiency of Lycopersicon esculentum in removing zinc from soil. The tomato plants were grown in soil applied with 100, 200, 300, 400 and 500ppm of zinc sulphate for 60 days. Every fortnight, soil samples were taken and analysed for the levels of Cu, Zn, Fe and Mn. Percent removal of zinc by the plant was calculated from the residual concentration. More removal was noticed in higher concentrations of zinc. After 60 days of treatment, levels of Cu, Zn, Fe and Mn were analysed in the above ground and below ground parts of the tomato plant. Zinc level was 90 ppm in both cases and the same in plants grown in all the concentrations of zinc sulphate. Fluctuations in chlorophyll content were noticed while decline was observed in microbial colonies. The data were subjected to two way analysis of variance and the results are discussed. Graphical Abstract
Jul 2020 DOI 10.14302/issn.2379-7835.ijn-20-3471
Spices have been frequently added to foods since ancient times, not only to enhance the taste but also as preservatives and medicinal agents. Their usage may be of concern due to possible contamination during processing and handling. The aim of this study was to investigate the physicochemical properties and heavy metals concentrations in some indigenous spices sold at two main markets namely Bodija and Apata markets in Ibadan, Oyo State, Nigeria. A total of eight commonly consumed spices were purposely analyzed for their proximate and mineral composition, physicochemical properties and anti-nutrients contents. Proximate analyses showed that the spices to contained (fresh matter ‘As consumed’) moisture content ranging from 11.74g in thyme to 59.36g/100g in scent leaves. Crude protein, fat, fibre, ash and carbohydrate contents ranged between 3.72 – 15.07g, 1.31 – 8.28g, 1.96 – 11.38g, 1.11 – 7.81g, and 17.80 – 50.77g/100g sample, respectively. All the spices contained high levels of potassium (176.3 – 739.6 mg), sodium (60.6 – 317 mg), calcium (78.5 – 423.9 mg), magnesium (82 – 322.1 mg) and iron (5.78 – 20.10 mg), but low levels of heavy metals – copper (0.17 – 0.68 mg), and manganese (0.32 – 1.05 mg)/100g respectively. Flavonoid was the most abundant phytochemical, while terpene was the least phytochemical in all the samples. The samples had very low concentrations of anti-nutrients, and could pose no threat to human health, as their values were within the regulatory standard. The antioxidants and phytochemicals in the spices can help in building up immunity and prevention of non-communicable diseases, hence, their consumption should be encouraged.
May 2020 DOI 10.14302/issn.2641-7669.ject-20-3313
Industrial effluents containing heavy metals may reach aquatic systems either through direct discharge or surface runoff and cause damage to aquatic organisms affecting their immune system and health. Hence the present study has been undertaken to observe the effects of hexavalent chromium on the WBCs of the fresh water fish, Labeorohita. WBCs play a major role in the immune response of the fish. For acute toxicity determination, healthy fish were subjected to static bioassays. The 24, 48, 72, and 96hr LC50 values were 50.88, 42.03, 28.09 and 10.87 ppm respectively. The fish were exposed to 0.5, 1, 1.5 and 2 ppm for 20 days. Differential count of WBCs and total WBC count were determined after every five days for twenty days. Lymphocytes exhibited a decline while the other cells and total WBC count exhibited an increase due to hexavalent chromium exposure. The results were subjected to two way analysis of variance.
Apr 2020 DOI 10.14302/issn.2637-6075.jpae-20-3322
In spite of the popularity of open-air waste dumping in Nigeria, it remains a relatively less effective waste management option across the globe because of its associated environmental impacts which includes the release of green house gases (GHGs), persistent organic pollutants (POPs), and metal micro-pollutants amongst others. This study aims to assess the potential environmental risks associated to metals released and vertically delineated across the soil profile within surroundings of dumpsite. Heavy metals in soil samples were acid-digested using the aqua-regia mixture of hydrochloric and nitric acid, followed by instrumentation analysis using the GBC 908 PBMT model atomic absorption spectrophotometer. Contaminated sites showed metal concentrations ranging from 1.493 to 109.460 mg/kg, 0.133 to 4.237 mg/kg, and 5.200 to 25.367 mg/kg for lead, cadmium and chromium respectively, with location 1 land area showing the most contamination. Only soil chromium was observed within regulatory stipulations in all cases. There was significant variation (p < 0.05) between the different sample locations, thereby indicating variations in composition of dumped wastes. Lead and cadmium showed the strongest positive correlation (r = 0.855, p < 0.01) and the application of some heavy metal pollution indicators revealed relatively higher metal loads and degree of contamination, as well as depicting potential ecological risk for soils of location 1. The significant heavy metal contamination of soils in the Tombia-Amassoma waste dumpsite requires that the local environmental sanitation and regulatory authorities take necessary remedial action to forestall the escalation of public health concerns that may emanate from this open-air dump.
Dec 2018 DOI 10.14302/issn.2691-3208.ijli-18-2476
Bivalves are used as bioindicators of heavy metals pollution because they are known to concentrate these elements, providing a time integrated indication of environmental contamination. Trace metals can reach high concentrations in sediments and also in aquatic organisms by bioaccumulation through the food chain. Six heavy metals (Hg, Zn, Pb, Fe, Mg and Cu) were collected and investigated from Abu Hummus, El Behara. The concentration of Hg was high in winter as 2.3µg/g in sediment. The Zn concentration was high in summer in sediment as 8.1µg/g. The Pb concentration was high in winter in water as 3.3µg/l. The concentration of Fe in sediment was high in summer as 492 µg/g. The concentration of Mg was high in sediment as 408µg/g. The concentration of Cu was high in summer in sediment as 301µg/g. The mean concentrations of Fe in the present study are within the permissible limits of law 48/1982 (<1 mg/l) and the guideline of (WHO, 1993) which is <1 mg/l. The mean concentration level of copper is within the permissible limits of law 48/1982 (<1.0 mg/l). The mean levels of the heavy metals (Hg, Zn, Pb, Fe, Mg and Cu) detected in the present study in the water stream are less than the permissible limits recommended by (USEPA, 2005). In the present study there is a significance between all seasons in the protein content in the soft tissue of Spathopsisrubensas the mean concentration level in Spring was reported as 102.83mg/g which is higher then that of autumn 100.5mg/g, summer 93.33 mg/g and winter 80.50 mg/g. In the present study the mean activity level of GPx in spring was higher than the other seasons such as spring 31.33u/g ˃ summer 28.33 u/g ˃Autumn 26.67 u/g ˃ winter 20.50u/g. The mean activity level of SOD in summer was higher than the other seasons such as summer 38.83 u/g ˃ spring 33.33 U /g ˃Autumn 28.83U/g ˃ winter 22.83U/g. The mean activity level of CAT in spring was higher than the other seasons such as spring 25.67u/g ˃ summer and autumn19.83u/g ˃ winter 15.17u/g. The mean activity level of MDA in winter was 30.50 U/g ˃ summer 22.50U/g ˃ autumn 18.0 U/g ˃ spring 16.83U/g. In the present study it was found that the mean activity level of MDA increased in winter at the same time the mean activity level of CAT, SOD and GPx were decreased in winter. Negative correlation was reported between CAT and Hg in winter as r=-0.88*. A positive correlation coefficient in winter was found between SOD activity level and CAT activity level as r=0.838*.
Feb 2018 DOI 10.14302/issn.2637-6075.jpae-17-1890
Cassava is the fourth largest staple food after rice, wheat and maize. Cassava is produced in the tropical and sub-tropical countries. Currently, the global production of cassava is about 215,436,496 tons. Out of these, Nigeria accounts for 20.3%, being the largest producing nation. During processing of cassava flour (Gari), three main wastes are generated including cassava mill effluents (CME), solid and gaseous emission. This paper reviews the impacts of CME in Nigeria. The study found that CME’s physicochemical quality often exceeds the limit for effluents discharge onto land and surface water as recommended by Federal Environmental Protection Agency (FEPA), Nigeria. CME alters the quality of soil and water with regard to physicochemical, heavy metal and microbial characteristics. CME can induce toxicological effects on the environments and its biota including humans, fisheries, flora and fauna. The impacts are mostly associated with physicochemical (viz: odour, cyanide, acidic, dissolved oxygen, biological and chemical oxygen demand, conductivity) and heavy metals characteristics. Therefore, there is the need for treatment and sustainable management strategies of CME through biotechnological advancement.