Contamination and Ecological Hazard Assessment of Heavy Metals in Freshwater Sediments and Oreochromis niloticus (Linnaeus, 1758) Fish Muscles in a Nile River Canal in Egypt

The most significant pollutants are the heavy metals in the aquatic network due to their toxicity, accumulation, and bio-magnification. In an attempt to characterize the physical-chemical and demonstrate the potential water impact of the heavy metal content of wastes in two lakes in Sharkia province, Egypt, this study was developed to determine their toxicity and the potential waste impacts in biochemistry and histology of fish muscle. Samples of water and fish muscles were collected and analyzed for heavy metals using atomic absorption of two different fish species (Oreochromis niloticus and Clarias gariepinus) along two canals in Sharkia province in Egypt during the four seasons in 2018. The water samples were also analyzed for the physicochemical parameters. The impact of heavy metal on the enzymatic antioxidant (superoxide dismutase and catalase) as well as the reduced glutathione content, besides the oxidative stress marker presented by lipid peroxidation levels in fish muscles, were evaluated. Results showed the largest amount of chloride (Cl-) and iron (Fe) in the Sharkia water sample, while Faquas water sample had the highest level of HCO3 and iron (Fe). The manganese concentration in the fish muscle was the highest in Sharkia water and the highest level of Fe was detected in the fish muscles collected from Faquas area. These high levels of some of the physicochemical parameters and heavy metals in the two lakes with two different wastes as seen in this study may be a source of water pollution. The highest accumulation of metals in the muscle of the two fish species, suggesting risk for human consumption. There were seasonal variations in the level of LPO in muscle tissue of two types of fishes with a reverse relationship with antioxidant parameters. This accumulation varied seasonal and spatial as well as according to the species of fish. Increasing the level of heavy metals effect on the biochemistry and histology of fish. Keywords: Heavy metals; Muscle; Oxidative/Antioxidant, Histology, Clarias gariepinus; Oreochromis niloticus

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Ecological hazard assessment via species sensitivity distributions: The non‐exchangeability issue

Biometrical Journal ◽

10.1002/bimj.201900404 ◽

2021 ◽

Author(s):

Sonia Migliorati ◽

Gianna Serafina Monti ◽

Marco Vighi

Keyword(s):

Hazard Assessment ◽

Species Sensitivity ◽

Ecological Hazard ◽

Species Sensitivity Distributions

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Analysis of Spatial Variability of River Bottom Sediment Pollution with Heavy Metals and Assessment of Potential Ecological Hazard for the Warta River, Poland

Minerals ◽

10.3390/min11030327 ◽

2021 ◽

Vol 11 (3) ◽

pp. 327

Author(s):

Joanna Jaskuła ◽

Mariusz Sojka ◽

Michał Fiedler ◽

Rafał Wróżyński

Keyword(s):

Heavy Metals ◽

Bottom Sediment ◽

Bottom Sediments ◽

Risk Index ◽

Point Sources ◽

Sediment Pollution ◽

Sample Collection ◽

Effect Concentration ◽

Ecological Hazard ◽

River Bottom

Pollution of river bottom sediments with heavy metals (HMs) has emerged as a main environmental issue related to intensive anthropopressure on the water environment. In this context, the risk of harmful effects of the HMs presence in the bottom sediments of the Warta River, the third longest river in Poland, has been assessed. The concentrations of Cr, Ni, Cu, Zn, Cd, and Pb in the river bottom sediments collected at 24 sample collection stations along the whole river length have been measured and analyzed. Moreover, in the GIS environment, a method predicting variation of HMs concentrations along the whole river length, not at particular sites, has been proposed. Analysis of the Warta River bottom sediment pollution with heavy metals in terms of the indices: the Geoaccumulation Index (Igeo), Enrichment Factor (EF), Pollution Load Index (PLI), and Metal Pollution Index (MPI), has proved that, in 2016, the pollution was heavier than in 2017. Assessment of the potential toxic effects of HMs accumulated in bottom sediments, made on the basis of Threshold Effect Concentration (TEC), Midpoint Effect Concentration (MEC), and Probable Effect Concentration (PEC) values, and the Toxic Risk Index (TRI), has shown that the ecological hazard in 2017 was much lower. Cluster analysis revealed two main groups of sample collection stations at which bottom sediments showed similar chemical properties. Changes in classification of particular sample collection stations into the two groups analyzed over a period of two subsequent years indicated that the main impact on the concentrations of HMs could have their point sources in urbanized areas and river fluvial process.

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Risk Assessment of Some Heavy Metals in Two Fish Species Oreochromis Niloticus and Clarias Gariepinus from Sharqia Province, Egypt

Journal of Veterinary Medicine and Research ◽

10.47739/veterinarymedicine.1204 ◽

2021 ◽

Vol 8 (1) ◽

pp. 1-5

Author(s):

Nahla S El-Shenawy ◽

Heba N Gad EL-Hak ◽

Mahi A Ghobashy ◽

Maha FM Soliman ◽

Farida A Mansour ◽

...

Keyword(s):

Heavy Metals ◽

Risk Assessment ◽

Human Health ◽

Health Risks ◽

Oreochromis Niloticus ◽

Clarias Gariepinus ◽

Human Health Risk ◽

Dry Weight ◽

Critical Problem ◽

Potential Health

Accumulation of heavy metals in fish is considered a critical problem for human health. Therefore, the study aimed to quantify the concentrations of iron (Fe), zinc (Zn), manganese (Mn), and lead (Pb) in Oreochromis niloticus and Clarias gariepinus from two areas in Al Sharqia governorate, Egypt, from September 2017 to August 2018. A human health risk assessment was conducted to evaluate the potential hazards associated with fish consumption. Metals concentrations (mg/kg dry weight) in muscles of catfish ranged 1.88-221.26 for Fe; 1.78-19.77 for Zn; BDL-238.51 for Mn; BDL-22.75 for Pb. In muscles of tilapia fish metals concentrations ranged 7.96-149.10 for Fe; 1.20-19.77 for Zn; BDL-230.82 for Mn; BDL-25.93 for Pb. Pb had Hazard quotients (HQs) which indicated potential health risks to tilapia consumers at both study areas and catfish consumers at the Faqous area. Fishermen were at higher risk compared to the other consumers.

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