scholarly journals Bioaccumulation of auto-mechanic wastes in the tissues of Pellonula Afzeliusi (Johnels, 1954) collected from Agba stream Ilorin, Kwara State, Nigeria

2021 ◽  
Vol 23 (2) ◽  
pp. 63-73
Author(s):  
O. A. Adeyemi-Ale ◽  
S. O. Oladipo ◽  
S. I. Abdulkareem
Keyword(s):  
Heavy Metals ◽  
Control Site ◽  
Water Bodies ◽  
Oil And Grease ◽  
Physico Chemical ◽  
Upstream Station ◽  
Liver And Kidney ◽  
Heavy Pollution ◽  
The University ◽  
Automobile Wastes

Hydrocarbons and heavy metals (HM) present in automobile wastes get into water bodies close to automobile mechanic villages. They deteriorate the physico-chemical qualities of such water bodies and exert toxic effects on fish and other aquatic fauna. They also pose risks to humans that consume fish from streams near such automechanic villages. There is paucity of information on the HM contents of Agba stream, Ilorin and no information on the bioaccumulation of HM in the tissues of Pellonula afzeliusi is currently available. The purpose of this study was to assess the physico-chemical qualities of water and bioaccumulation of HM in the tissues of Pellonula afzeliusi fish collected from Agba stream, Ilorin, Kwara State, Nigeria. Water and samples of Pellonula afzeliusi were collected from the upstream (station A), midstream (station B) of Agba stream located close to an auto-mechanic village and Oyun dam (control site, station C) located within the University of Ilorin. Standard methods were used to analyse oil and grease (OG), total petroleum hydrocarbon (TPH) and HM in water samples. The concentrations of TPH and HM were analysed in the skin, bone, muscle, gills, gastrointestinal tract, liver and kidney of the fish. The order of water HM concentrations indicated Zn > Cd > Ba> Fe > Pb at station A; Cd > Zn > Fe > Ba > Pb at station B, and Zn > Ba > Pb > Fe >Cd at station C. TPH and HM bioaccumulated in the tissues of fish while lead was not detected in all tissues from station C. Bioaccumulation factor varied with the highest values  t station C. The result of this study indicated heavy pollution burden in station B with lower pollution burden in station C (the control site). These call for attention of government in ensuring ecological restoration and prevention of further discharge of automobile wastes into the stream. Keywords: Automobile wastes, Heavy metals, Hydrocarbons, Bioaccumulation, Pellonula afzeliusi

scholarly journals Assessment of Heavy Metals, Organic Carbon and Physico-Chemical Properties of Roadside Dust from a Nigerian School Campus

2020 ◽  
Vol 4 (1) ◽  
pp. 1-12
Author(s):  
O. D. Olayinka ◽  
F.O. Nwosu ◽  
S. O. Ahmed ◽  
S.F. Fabiyi ◽  
O. J. Ajala
Keyword(s):  
Heavy Metals ◽  
Organic Carbon ◽  
Bulk Density ◽  
Particle Density ◽  
Chemical Properties ◽  
Pollution Index ◽  
Absorption Spectrometry ◽  
Control Site ◽  
Physico Chemical ◽  
Roadside Dust

University of Ilorin is one of the most populated Universities in Nigeria. Roadside dust was collected from the busiest roads of the university permanent site and level of heavy metals (Fe, Cu, Zn, Cd and Pb), organic carbon and physico-chemical properties of the dust were assessed. Atomic Absorption Spectrometry (Buck Scientific 210/211VGP) was used to analyse for heavy metals while appropriate standard methods were employed for the determination of organic carbon, pH, conductivity, particle density and bulk density of the roadside dust. The pH of dust from all roads was almost alkaline (7.2 – 7.6), particle density ranged from 1.60 - 2.14 gml-1, bulk density ranged from 1.03 – 1.62 gml-1, electrical conductivity ranged from 0.25 to 0.57µScm-1, organic carbon (OC) content of all roadside dust ranged from 0.9 % - 1.2 %. While Pb was obtained to be absent in all the roadside dust samples, it was observed that the abundance of other heavy metals at all the various sampling points and control followed the order Fe >>>Zn >> Cu > Cd. The average level of Fe in the control site was 2443.85 mg/kg which was very lower to that from other sites in the study. The results for the metal pollution index (MPI) show that all the roads were polluted with Fe, Cu, Zn and Cd. The levels of the metals showed a dependence on anthropogenic pollution such as vehicle density compared with the control site.

THYROID STIMULATORS AND THYROID STIMULATION

1971 ◽  
Vol 66 (3) ◽  
pp. 558-576 ◽  
Author(s):  
Gerald Burke
Keyword(s):  
Regulatory System ◽  
Control Site ◽  
Thyroid Cell ◽  
Primary Control ◽  
Physico Chemical ◽  
Site Of Action ◽  
Long Acting

ABSTRACT A long-acting thyroid stimulator (LATS), distinct from pituitary thyrotrophin (TSH), is found in the serum of some patients with Graves' disease. Despite the marked physico-chemical and immunologic differences between the two stimulators, both in vivo and in vitro studies indicate that LATS and TSH act on the same thyroidal site(s) and that such stimulation does not require penetration of the thyroid cell. Although resorption of colloid and secretion of thyroid hormone are early responses to both TSH and LATS, available evidence reveals no basic metabolic pathway which must be activated by these hormones in order for iodination reactions to occur. Cyclic 3′, 5′-AMP appears to mediate TSH and LATS effects on iodination reactions but the role of this compound in activating thyroidal intermediary metabolism is less clear. Based on the evidence reviewed herein, it is suggested that the primary site of action of thyroid stimulators is at the cell membrane and that beyond the(se) primary control site(s), there exists a multifaceted regulatory system for thyroid hormonogenesis and cell growth.

The change in agrochemical indicators of soil fertility under the influence of heavy metal contamination

2016 ◽  
Vol 2 (91) ◽  
pp. 17-21
Author(s):  
S. H. Korsun ◽  
N. I. Dovbash
Keyword(s):  
Heavy Metals ◽  
Forest Soil ◽  
Heavy Metal Contamination ◽  
Gray Forest Soil ◽  
Mineral Fertilizers ◽  
Background Concentration ◽  
Physico Chemical ◽  
Natural Background Concentration ◽  
Nitrogen Phosphorus ◽  
Hydrolytic Acidity

The aim of the study was to establish changes in the physico-chemical and agrochemical characteristics of gray forest large-clay loamy soil, depending on the contamination of ecotopes by heavy metals. Methods. Field, laboratory, mathematical and statistical. Results. The results of the study of the soil of areas with an over-dimensioned content of heavy metals and the transformation of agrochemical characteristics of gray forest soil in the cultivation of corn for grain. It was established that under conditions of systematic application of mineral fertilizers in agrocenoses, an increase in the lead concentration to 100 mg/kg, cadmium to 2,0, zinc to 50 mg/kg in gray forest soil did not result in a decrease in the amount available forms of nitrogen, phosphorus, potassium by plants, compared with the natural background. Concentration of lead in the amount of 1000 mg/kg, cadmium – 20, zinc – 500 mg/kg marked an increase in exchange and hydrolytic acidity and loss of humus.

scholarly journals Assessment of the Impact of Small Hydropower Plants on the Ecological Status Indicators of Water Bodies: A Case Study in Lithuania

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 433
Author(s):  
Laima Česonienė ◽  
Midona Dapkienė ◽  
Petras Punys
Keyword(s):  
Water Quality ◽  
Benthic Macroinvertebrates ◽  
Suspended Solids ◽  
Ecological Status ◽  
Fish Abundance ◽  
Water Bodies ◽  
Small Hydropower ◽  
Hydropower Plants ◽  
Physico Chemical ◽  
The Impact

Hydropower plants produce renewable and sustainable energy but affect the river’s physico-chemical characteristics and change the abundance and composition of the aquatic organisms. The impact of large HPPs on the ecological conditions of surface water bodies have been extensively studied, but less attention has been paid to environmental impact studies of small hydropower plants (SHPs). The impact of hydropeaking on both the river flow regime and ecosystems has been well-studied for peaking mode plants, mainly medium to large-sized ones. However, for small hydroelectric power plants, and especially for those in lowland rivers, the available information on water quality, benthic macroinvertebrates communities and fish abundance, and biomass is not sufficient. Ten small hydropower plants were selected, and the ecological status of water bodies was assessed in different parts of Lithuania. The studies were performed at the riverbed upstream from the SHPs, where the hydrological regime has not changed, and downstream from the SHPs. It was found that the small hydropower plants do not affect the physico-chemical values of the water quality indicators. This study demonstrated that the total number of benthic macroinvertebrates taxa (TS) is influenced by the concentration of nitrogen and suspended solids, the water flow, the river area, and the current speed; the number of EPT (Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies)) taxa is influenced by the concentration of nitrogen and suspended solids. The studied indicators do not have a significant impact on biomass. The SHPs affect the fish abundance and biomass. The Lithuanian fish index (LFI) is influenced by the average depth and area of the river. Some SHPs operating in lowland areas may yield somewhat significant hydrograph ramping but more detailed investigation is needed to support the significance of this impact on the biological indices.

scholarly journals Optimal Solutions for the Use of Sewage Sludge on Agricultural Lands

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 585
Author(s):  
Catalina Iticescu ◽  
Puiu-Lucian Georgescu ◽  
Maxim Arseni ◽  
Adrian Rosu ◽  
Mihaela Timofti ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Sewage Sludge ◽  
Agricultural Production ◽  
Agricultural Land ◽  
Chemical Characteristics ◽  
Optimal Solutions ◽  
Physico Chemical ◽  
Agricultural Areas ◽  
The Impact ◽  
Made In

The use of sewage sludge in agriculture decreases the pressure on landfills. In Romania, massive investments have been made in wastewater treatment stations, which have resulted in the accumulation of important quantities of sewage sludge. The presence of these sewage sludges coincides with large areas of degraded agricultural land. The aim of the present article is to identify the best technological combinations meant to solve these problems simultaneously. Adapting the quality and parameters of the sludge to the specificity of the land solves the possible compatibility problems, thus reducing the impact on the environment. The physico-chemical characteristics of the fermented sludge were monitored and optimal solutions for their treatment were suggested so as to allow that the sludge could be used in agriculture according to the characteristics of the soils. The content of heavy metals in the sewage sludge was closely monitored because the use of sewage sludge as a fertilizer does not allow for any increases in the concentrations of these in soils. The article identifies those agricultural areas which are suitable for the use of sludge, as well as ways of correcting some parameters (e.g., pH), which allow the improvement of soil quality and obtained higher agricultural production.

Removal of heavy metal from soil and groundwater by in-situ electrokinetic remediation

2000 ◽  
Vol 42 (7-8) ◽  
pp. 335-343 ◽  
Author(s):  
S. Shiba ◽  
S. Hino ◽  
Y. Hirata ◽  
T. Seno
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Electric Potential ◽  
Potential Gradient ◽  
Electrokinetic Remediation ◽  
Contaminated Aquifer ◽  
Physico Chemical ◽  
Operational Variables ◽  
Mass Transport Process

The operational variables of electrokinetic remediation have not been cleared yet, because this method is relatively new and is an innovative technique in the aquifer remediation. In order to investigate the operational variables of the electrokinetic remediation, a mathematical model has been constructed based on the physico chemical mass transport process of heavy metals in pore water of contaminated aquifer. The transport of the heavy metals is driven not only by the hydraulic flow due to the injection of the purge water but also by the electromigration due to the application of the electric potential gradient. The electric potential between anode and cathode is the important operational variable for the electrokinetic remediation. From the numerical simulations with use of this model it is confirmed that the remediation starts from the up stream anode and gradually the heavy metal is transported to the down stream cathode and drawn out through the purge water.

Assessment of Heavy Metals Content in the Proximity of a Contaminated Site From Cluj-Napoca (Romania)

2020 ◽  
Vol 65 (2) ◽  
pp. 17-37
Author(s):  
Georgiana Grosu ◽  
◽  
Carmen Andreea Roba ◽  
Ramona Bălc ◽  
Maria Lucia Bizău-Cârstea ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Statistical Analysis ◽  
Multivariate Statistical Analysis ◽  
Sediment Contamination ◽  
Contaminated Site ◽  
Pollution Indices ◽  
Chemical Parameters ◽  
Multivariate Statistical ◽  
Water And Sediment ◽  
Physico Chemical

The present study was conducted in the proximity of a contaminated site from Cluj-Napoca city (Cluj County, Romania), where metal processing activities have been carried out for decades. Metal content and physico-chemical parameters were analyzed in soil, water and sediment samples, while organic matter (OM) and total organic carbon (TOC) was additionally analyzed for the soil samples. The sources of heavy metals were evaluated based on multivariate statistical analysis, while the soil and sediment contamination degree was assessed based on specific pollution indices. The calculated indices indicated a significant pollution with Cd and Pb, which may represent a risk if the area would become a residential area. Keywords: heavy metals, contaminated site, soil pollution indices, multivariate statistical analysis, Cluj-Napoca

Phytoplankton of cold-water lake ecosystems under the influence of natural and anthropogenic factors

2021 ◽  
pp. 42-49
Author(s):  
Andrey N. Sharov
Keyword(s):  
Heavy Metals ◽  
Cold Water ◽  
Arctic Lakes ◽  
Water Bodies ◽  
The Arctic ◽  
Anthropogenic Factors ◽  
Large Lakes ◽  
Arctic Water ◽  
The North ◽  
Natural And Anthropogenic Factors

Based on the study of the spatio-temporal aspects of the development of phytoplankton in the lakes of the North and North-West of the European territory of Russia (large lakes – Imandra, Onega and Chudsko-Pskovskoye and small lakes of the Arctic and Subarctic), the features of its structure and dynamics under the influence of natural and anthropogenic factors (eutrophication, heavy metal pollution, acidification, thermification). The species composition and quantitative characteristics of phytoplankton of large lakes of the North of Russia, small arctic lakes and lakes of subarctic regions are studied. It has been shown that diatoms predominate in arctic water bodies according to species diversity, and green and diatoms predominate in boreal ones. By biomass, diatoms dominate mainly in all cold-water lakes, with the exception of small arctic lakes, where golden algae lead. The features of the reorganization of phytoplankton in response to the action of anthropogenic factors are revealed. It is proved that in the northern water bodies the complex action of heavy metals and nutrients does not lead to inhibition of phytoplankton, and the effect of acidification in combination with heavy metals enhances the toxic effect of the latter. A feature of the response to acidification is an increase in the variability of the dynamics of the biomass of phytoplankton. It has been shown that in different types of lakes of East Antarctica under severe climate conditions under light and biogenic limitation, redistribution of autotrophic components in the formation of the biota of water bodies occurs: against the background of a decrease in the abundance and diversity of phytoplankton, the role of microphytobenthos and periphyton increases.

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