Assessment of sediment quality and pore water ecotoxicity in Kebir Rhumel basin (NE-Algeria): a combined approach

2012 ◽  
Vol 65 (2) ◽  
pp. 393-401 ◽  
Author(s):  
Leila Sahli ◽  
Fatima-Zohra Afri-Mehennaoui ◽  
Mohamed El Hadef El Okki ◽  
Jean François Férard ◽  
Smail Mehennaoui
Keyword(s):  
Trace Metal ◽  
Growth Inhibition ◽  
Pore Water ◽  
Sediment Quality ◽  
Pseudokirchneriella Subcapitata ◽  
Toxicity Tests ◽  
Sediment Pore Water ◽  
Acute Test ◽  
Flame Atomic Absorption ◽  
Metal Contents

The objectives of this study are to use different approaches to assess the current pollution status in the wadis of the Kebir Rhumel basin. First, sediment trace metal contents were measured by flame atomic absorption spectroscopy. Then, sediment quality was assessed on the basis of contamination assessment indexes such as: Geoaccumulation Index (Igeo), Contamination factor (Cf), Contamination degree (Cd), Sediment Pollution Index (SPI) and SEQ guidelines (Consensus Sediment Quality Guidelines). In addition, several toxicity tests (Daphnia magna mobility inhibition acute test-48 h, Aliivibrio fischeri luminescence inhibition acute test – 15/30 mn and Pseudokirchneriella subcapitata growth inhibition chronic test – 72 h) were conducted to assess sediment pore water ecotoxicity. Trace metal concentrations followed the order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Indexes used indicate varying degrees of sediment quality. Igeo, Cf, Cd and SPI reveal a polymetallic contamination dominated by two or more elements in which Cd, Cu and Pb are of greatest concern. SEQ guidelines showed that biological effects on fauna would likely be observed occasionally and/or frequently for Cd, Cr, Cu, Pb and Zn contents. Test organisms exposed to sediment pore water showed that the algal P. subcapitata test was more sensitive than the D. magna and A. fischeri tests. Hence, algal growth inhibition proved to be the most sensitive response to contaminants present in sediment extracts but a significant relationship with trace metal contents was not demonstrated.

Bicarbonate as a Potential Confounding Factor in Cladoceran Toxicity Assessments of Pore Water from Contaminated Sediments

1992 ◽  
Vol 49 (8) ◽  
pp. 1633-1640 ◽  
Author(s):  
Robert A. Hoke ◽  
William R. Gala ◽  
James B. Drake ◽  
John P. Giesy ◽  
Stan Flegler
Keyword(s):  
Pore Water ◽  
Ceriodaphnia Dubia ◽  
Toxicity Tests ◽  
Metabolic Inhibitor ◽  
Pore Waters ◽  
Sediment Pore Water ◽  
International Joint Commission ◽  
Reference Toxicant ◽  
Area Of Concern ◽  
Pore Water Sample

Elevated alkalinity values measured in sediment pore water samples from the Grand Calumet River–Indiana Harbor Canal, an International joint Commission Area of Concern (AOC), caused concern over the potential effects of alkalinity on cladoceran test responses. Forty-eight-hour tests with NaHCO3 and NaCl as reference toxicants indicated that NaHCO3 toxicity to Daphnia magna and Ceriodaphnia dubia was due to both Na+ and HCO3−, although greater HCO3− toxicity was observed to D. magna. Theoretical HCO3− concentrations in sediment pore waters from the AOC demonstrated sufficient HCO3− in several samples to produce acute toxicity, based on 48-h LC50s from the reference toxicant tests. X-ray microanalysis was conducted to qualitatively assess the effects on internal Cl− levels of D. magna after exposure to NaHCO3, to an AOC sediment pore water sample, and to NaSCN, a metabolic inhibitor of Cl− uptake. Based on these results the proposed mechanism of HCO3− toxicity to D. magna is the inhibition of the active uptake of Cl− from water. We suggest that pore water alkalinity should be considered when interpreting the results of sediment pore water and effluent toxicity tests with D. magna, other cladocerans, and, perhaps, other invertebrates and fish.

scholarly journals Trace Metals Contamination in Bread Ingredients and Bread from Bakeries in Nigeria

2020 ◽  
pp. 26-37
Author(s):  
V. O. E. Akpambang ◽  
A. P. Onifade
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Human Consumption ◽  
Flame Atomic Absorption ◽  
Flame Atomic Absorption Spectrophotometer ◽  
Regular Consumption ◽  
Metal Contents ◽  
Wheat Flours ◽  
Toxic Trace Metals ◽  
Range Of Values

Bread loaves and bread ingredients (wheat flours, salt, sugar, yeast and water) were randomly sampled from ten bakeries within Akure metropolis of south western Nigeria and analysed to determine their safety levels for human consumption with respect to trace metal contents. The trace metals (Cu, Zn, Mn, Cr, Cd and Pb) were analysed in the samples using flame atomic absorption spectrophotometer. Results obtained revealed that toxic trace metals such as Cr, Cd and Pb were not detected in any of the samples. However, the levels of essential trace metals such as Cu, Zn and Mn had range of values in mg/kg: (0.039 – 0.091), (0.837 – 3.310) and (0.035 – 3.148); (0.056 – 0.091), (0.034 – 2.755) and (0.054 – 1.054) in the wheat flours and bread samples analysed respectively. This study revealed that the bread ingredients and loaves of bread sampled contained essential trace metals at levels that could not threaten the health of consumers over prolonged regular consumption.

Interpretation of coastal sediment quality based on trace metal and PAH analysis, benthic foraminifera, and toxicity tests (Sardinia, Western Mediterranean)

2015 ◽  
Vol 94 (1-2) ◽  
pp. 72-83 ◽  
Author(s):  
Marco Schintu ◽  
Carla Buosi ◽  
François Galgani ◽  
Alessandro Marrucci ◽  
Barbara Marras ◽  
...  
Keyword(s):  
Trace Metal ◽  
Benthic Foraminifera ◽  
Sediment Quality ◽  
Western Mediterranean ◽  
Coastal Sediment ◽  
Toxicity Tests

A comparative biogeochemical study of sediments from Kandalaksha Bay, White Sea, Russian Arctic

Polar Record ◽  
2003 ◽  
Vol 39 (4) ◽  
pp. 357-367 ◽  
Author(s):  
Sofia Koukina ◽  
Galina Korneeva ◽  
Lioudmila Ametistova ◽  
Tatiana Bek
Keyword(s):  
Organic Matter ◽  
Trace Metal ◽  
White Sea ◽  
Sediment Quality ◽  
Enzymatic Activities ◽  
Small Scale ◽  
Russian Arctic ◽  
Geochemical Composition ◽  
Kandalaksha Bay ◽  
Metal Contents

Major (Al, Fe), minor (Mn), and trace (Li, Cu, Ni, Cr, Cd, Zn, Pb) metals along with nutrients (TOC, TON, TS, TP) and enzymatic activities were determined in 18 surface sediment and two soil samples collected in six small bays of the Karelian shore of Kandalaksha Bay, White Sea, Russian Arctic. The studied sediments tended to be marine, with a major input of organic matter from autochthonous sources. Marine organic material might be an important carrier of trace metals in the examined sediments. According to sediment quality guidelines, all trace-metal contents were below the threshold levels. The results of azocasein-trypsin tests also suggested no significant contamination of analysed sediments and soils. A comparison of the trace-metal contents in the sediments examined with those of the western Arctic shelf showed higher levels of Zn and Cr in the Karelian shore. Presumably these disparities were related to regional differences in sediment chemistries rather than to any enhanced pollution within the studied area. Both geochemical composition and enzymatic-activities patterns among sites studied are largely controlled by the sediment granulometry. The evolution of sediments in the restricted exchange environments under investigation is caused by depositional conditions, which are strongly affected by small-scale hydrodynamic processes specific for each particular area. The most vivid examples are separating basins, where the fine-grained sediments enriched in organic matter — and thus in nutrients and metals — are formed under calm hydrodynamic conditions enhanced by severely restricted water exchange.

Spatial and seasonal variations and ecotoxicological significance of sediment trace metal concentrations in Kebir-Rhumel basin (Northeast of Algeria)

2011 ◽  
Vol 64 (8) ◽  
pp. 1759-1766 ◽  
Author(s):  
Leila Sahli ◽  
Fatima-Zohra Afri-Mehennaoui ◽  
Mohamed El Hadef El Okki ◽  
Christian Blaise ◽  
Smail Mehennaoui
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Extreme Values ◽  
Biological Effects ◽  
Sediment Quality ◽  
Aquatic Organisms ◽  
Flame Atomic Absorption ◽  
Probable Effect Level ◽  
Threshold Effect Level ◽  
Effect Level

This study sought to assess sediment contamination by trace metals (cadmium, chromium, cobalt, copper, manganese, nickel, lead and zinc), to localize contaminated sites and to identify environmental risk for aquatic organisms in Wadis of Kebir Rhumel basin in the Northeast of Algeria. Water and surficial sediments (0–5 cm) were sampled in winter, spring, summer and autumn from 37 sites along permanent Wadis of the Kebir Rhumel basin. Sediment trace metal contents were measured by Flame Atomic Absorption Spectroscopy. Trace metals median concentrations in sediments followed a decreasing order: Mn > Zn > Pb > Cr > Cu > Ni > Co > Cd. Extreme values (dry weights) of the trace metals are as follows: 0.6–3.4 μg/g for Cd, 10–216 μg/g for Cr, 9–446 μg/g for Cu, 3–20 μg/g for Co, 105–576 μg/g for Mn, 10–46 μg/g for Ni, 11–167 μg/g for Pb, and 38–641 μg/g for Zn. According to world natural concentrations, all sediments collected were considered as contaminated by one or more elements. Comparing measured concentrations with American guidelines (Threshold Effect Level: TEL and Probable Effect Level: PEL) showed that biological effects could be occasionally observed for cadmium, chromium, lead and nickel levels but frequently observed for copper and zinc levels. Sediment quality was shown to be excellent for cobalt and manganese but medium to bad for cadmium, chromium, copper, lead, nickel and zinc regardless of sites.

REY distribution and concentration in bottom seawater and oxic pore water in the CCZ, NE Pacific: pilot study on the application of a DGT passive sampling method in deep sea environments

2020 ◽  
Author(s):  
Katja Schmidt ◽  
Sophie Anna Luise Paul ◽  
Cornelia Kriete
Keyword(s):  
Trace Elements ◽  
Trace Metal ◽  
Pore Water ◽  
Deep Sea ◽  
Passive Sampling ◽  
Sampling Method ◽  
Passive Samplers ◽  
Sediment Pore Water ◽  
Ce Anomaly

<p>Sampling and analysis of trace elements in open seawater and in sediment pore water in the deep sea is challenging due to small sample volumes and matrix effects. Here we evaluate an alternative method using the technique of diffusive gradients in thin films (DGT passive samplers), focussing on rare earth elements and yttrium (REY). DGT measures the labile fraction of metals in situ by fixing them on a Chelex resin after diffusion through a gel layer, providing a diffusive flux and averaged in situ concentrations of elements during the time of deployment. As the accumulated element concentrations increase with exposure time to solution, long-term deployment times overcome low trace metal concentrations in seawater and pore water. So far, no deep-sea applications of passive samplers are yet reported.</p><p>Sampling was performed in bottom seawater and surface sediments in the German licence area for manganese nodule exploration in the Clarion Clipperton Zone (CCZ, research cruise SO268 in April/May 2019), deployment times ranged from 12 hours in sediments to 4 weeks in open seawater.</p><p>Seawater DGT’s were deployed 0.5 m to 8 m above the seafloor. PAAS-normalized REY show the typical seawater pattern, with increase from LREE to HREE, a strong negative Ce anomaly, a kink from Gd to Tb, and a pronounced positive Y/Ho anomaly. The pattern and calculated concentrations agree very well with reported dissolved REY (<0.2 µm) for Pacific deep water (Alibo and Nozaki, 1999). Sediment DGT sticks were deployed in cores taken with a multicorer and cover the first 15 cm of the sediment. They provide in situ high-resolution profiles of trace metal fluxes and were analysed in 0.5 cm to 2 cm segments. We observe smooth PAAS-normalized patterns with negative Ce anomaly, an increase from LREE to MREE, and a slight decrease from Tb to Lu, sometimes accompanied by a small positive Y/Ho anomaly. The calculated concentrations generally increase with depth. Paul et al (2019) previously described very similar distribution patterns for CCZ sediment pore water and suggested Mn and Fe phases as the REY source. The pore water REY patterns clearly differ from bottom seawater already in the first centimetres of surface sediment– this sharp shift demonstrates that the dissolved pore water REY pool in the sediment surface is controlled by fluid-mineral equilibria.</p><p>The DGT passive sampling method may provide an additional tool to investigate biogeochemical processes at the deep-sea sediment-water interface and in the open ocean, and to monitor effects of anthropogenic disturbances at the seafloor on benthic trace element fluxes. We will discuss uncertainties of concentration calculation resulting from diffusion coefficients and from non-steady state conditions in pore water, and the comparability of DGT-derived distribution pattern and concentrations with results from physically filtered water. The DGT labile fraction is thought to represent the bioavailable fraction of trace elements and may also include colloids and nanoparticles (NPCs).</p><p> </p><p>Alibo and Nozaki, 1999: Geochimica et Cosmochimica Acta 63, pp. 363-372.</p><p>Paul et al, 2019: Geochimica et Cosmochimica Acta 251, pp. 56-72.</p>

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