scholarly journals The rainfall effect onto solidification and stabilization of heavy metal-polluted sediments

2020 ◽  
Vol 7 (7) ◽  
pp. 192234
Author(s):  
Yan Sun ◽  
Daofang Zhang ◽  
Feipeng Li ◽  
Hong Tao ◽  
Moting Li ◽  
...  

Rainfall makes impacts on the process of solidification/stabilization (S/S) and the long-term safety of solidified matrix. In this study, the effect of rainfall on solidification/stabilization process was investigated by the rainfall test. The unconfined compressive strength (UCS) and toxicity characteristic leaching procedure (TCLP) were adopted to characterize the properties of S/S sediments before and after the rainfall test. The samples cured for 28 days were selected for semi-dynamic leaching tests with a simulated acidic leachant prepared at pH of 2.0, 4.0 and 7.0. The effectiveness of S/S treatment was evaluated by diffusion coefficient ( D e ) and leachability index (LX). The results indicated that UCS decreased at maximum deterioration rate of 34.23% after 7 days of curing, along with the minimum rate of 7.98% after 28 days by rainfall, with greater than 14 days referred. The rainfall had little effect on the leaching characteristics of heavy metals during the curing process. However, the simulated acid rain made significant impacts on the leaching behaviours of the heavy metals in the S/S materials. All the values of cumulative fraction of leached heavy metals were less than 2.0%, exhibition of good stabilization of cement. Furthermore, the calculated diffusion coefficient ( D e ) for Cu was 1.28 × 10 1 cm 2 s –1 , indicating its low mobility of heavy metal ions in S/S sediments. Furthermore, the calculated diffusion coefficients ( D i ) for Cd, Cu and Pb were 7.44 × 10 −11 , 8.18 × 10 −12 and 7.85 × 10 −12 cm 2 s –1 , respectively, indicating their relatively low mobility of heavy metal in S/S sediments.

2007 ◽  
Vol 7 ◽  
pp. 192-197 ◽  
Author(s):  
M. F. Hovmand ◽  
Kaare Kemp

Atmospheric bulk deposition of heavy metals (HM) was measured from 1972/73 to the present time at five to ten forest sites in rural areas of Denmark. From 1979, HM in aerosols were measured at one to four forest sites. On the basis of these long-term continuous measurements, the atmospheric inputs to the forest floor have been calculated. Yearly HM emission estimates to the European atmosphere seems to correlate well with yearly average values of HM deposition, as well as with HM concentrations in the ambient atmosphere. HM emissions have been estimated since the 1950s. Using the correlation between emission and deposition, HM deposition values maybe extrapolated in reverse chronological order. The accumulated atmospheric HM deposition has been estimated in this way over a period of 50 years.


2021 ◽  
Vol 8 ◽  
Author(s):  
Franziska Grundler ◽  
Gilles-Eric Séralini ◽  
Robin Mesnage ◽  
Vincent Peynet ◽  
Françoise Wilhelmi de Toledo

Background: Dietary exposure to environmental pollutants in humans is an important public health concern. While long-term fasting interrupts the dietary exposure to these substances, fat mobilization as an energy source may also release bioaccumulated substances. This was, to our knowledge, only investigated in obese people decades ago. This study explored the effects of 10-days fasting on the excretion of heavy metals and glyphosate.Methods: Urinary levels of arsenic, chromium, cobalt, lead, nickel, mercury and glyphosate were measured before and after 10 fasting days in 109 healthy subjects. Additionally, hair analysis was done before and ten weeks after fasting in 22 subjects.Results: Fasting caused a decrease in body weight, and in urinary arsenic (by 72%) and nickel (by 15%) concentrations. A decrease in lead hair concentrations (by 30%) was documented. Urinary mercury levels were unchanged for chromium, cobalt and glyphosate, which were undetectable in most of the subjects. Additionally, fatigue, sleep disorders, headache and hunger were reduced. Body discomfort symptoms diminished four weeks after food reintroduction.Conclusions: The results of this study provide the first insights into the changes in heavy metal excretion caused by long-term fasting. Further studies focusing on the kinetics of efflux between different compartments of the body are needed.Clinical Trial Registration:https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00016657, identifier: DRKS00016657.


2018 ◽  
Vol 10 (8) ◽  
pp. 2684 ◽  
Author(s):  
Giorgio Provolo ◽  
Giulia Manuli ◽  
Alberto Finzi ◽  
Giorgio Lucchini ◽  
Elisabetta Riva ◽  
...  

Cattle and pig manure contain useful mineral nutrients (N, P, and K) and are therefore used as organic fertilizer. However, excessive applications of manure can cause environmental problems and threaten animal and human health because these materials also hold significant amounts of heavy metals, particularly Cu and Zn. To assess the potential risk due to the increased concentrations of heavy metals (Cu, Mn, Zn, and Cr) in a harvested crop, two maize hybrids were grown in pots on four different soils with three different fertilisers (urea, pig manure, and cattle manure). Both soil and manure characteristics influenced the heavy metal concentrations in the plant shoots. Organic fertilisation strongly interacted with the soils and, in general, reduced the shoot content of Cu, Mn, and Zn. A preliminary assessment of the heavy metal balance of the agricultural systems based on the intensive livestock production and maize cultivation showed that the potential soil enrichment of the long-term application of livestock manure arises mainly from the application of pig slurries that have a high content of Cu and Zn. The time required to apply an amount of metal that is equal to the initial soil content is 60–300 years for Zn and 240–450 years for Cu, depending on the soil type and the initial heavy metal content.


2013 ◽  
Vol 664 ◽  
pp. 683-689 ◽  
Author(s):  
Shu Cong Zhen ◽  
Yong Xun ◽  
Bu Quan Miao

Heavy metals, including Pb, Cr, Cd, Zn, Cu and Ni, were solidified/stabilized by magnesium potassium phosphate cement (MKPC). The unconfined compressive strength test shows that the strengths of the solidified bodies containing 10%-40% MKPC all exceeded 0.5 MPa, which have met the requirements of storage and landfilling. The toxicity characteristic leaching procedure (TCLP) test shows that no detectable Pb, Cr and Cd were leached from the solidified body containing 40% MKPC after being cured standardly for 28 days, and the concentrations of heavy metals leached from the solidified body containing 10% MKPC after being cured for only 7 days were still significantly lower than the limits in related Chinese National Standards. The leaching concentrations of heavy metals followed a descending order of Cu>Zn>Ni>Pb>Cd>Cr. In the simulated acid rain eluviation test, heavy metals were eluviated in different patterns, and the sequence of releasing amounts was similar to that of leaching concentrations. The experimental results indicate that heavy metals can be satisfactorily solidified by MKPC.


Author(s):  
Francesco Lombardi ◽  
Giulia Costa ◽  
Maria Chiara Di Lonardo ◽  
Alessio Lieto

This work evaluated and compared potential impacts related to the accumulation and/or release of heavy metals resulting from the application of different types of stabilized waste to soil. Namely, the following three types of flows were considered: waste produced by aerobic bio-stabilization of municipal solid waste at a Mechanical Biological Treatment (MBT) plant, and compost produced either from aerobic composting or from a combination of anaerobic and aerobic biodegradation processes. After a preliminary characterization of the materials (organic matter content, volatile solid, and heavy metals content), heavy metal accumulation in soil caused by possible long-term application of these organic materials was evaluated by implementing a discretized mass balance based on the total content of the heavy metals in each type of solid matrix investigated. In addition, results of percolation leaching tests performed on each type of material were presented and discussed. Results highlight that although the total content of heavy metals of the three types of materials differed considerably, with the MBT waste presenting the highest concentrations, the results of the leaching percolation tests were quite similar.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Yintao Lu ◽  
Hong Yao ◽  
Dan Shan ◽  
Yichen Jiang ◽  
Shichao Zhang ◽  
...  

Soil and plant samples were collected from Tongliao, China, during the maize growth cycle between May and October 2010. Heavy metals, such as Cr, Pb, Ni, and Zn, were analyzed. The concentrations of Cr, Pb, Ni, and Zn in the wastewater-irrigated area were higher than those in the topsoil from the groundwater-irrigated area. The concentrations of metals in the maize increased as follows: Pb < Ni < Zn < Cr. In addition, Cr, Pb, and Ni mainly accumulated in the maize roots, and Zn mainly accumulated in the maize fruit. The results of translocation factors (TF) and bioconcentration factors (BCF) of maize for heavy metals revealed that maize is an excluder plant and a potential accumulator plant and can serve as an ideal slope remediation plant. In addition, the increasing heavy metal contents in soils that have been polluted by wastewater irrigation must result in the accumulation of Cr, Pb, Ni, and Zn in maize. Thus, the pollution level can be decreased by harvesting and disposing of and recovering the plant material.


2003 ◽  
Vol 60 (4) ◽  
pp. 793-806 ◽  
Author(s):  
Maria Lucia Azevedo Silveira ◽  
Luís Reynaldo Ferracciú Alleoni ◽  
Luiz Roberto Guimarães Guilherme

The application of sewage sludge or biosolids on soils has been widespread in agricultural areas. However, depending on their characteristics, they may cause increase in heavy metal concentration of treated soils. In general, domestic biosolids have lower heavy metal contents than industrial ones. Origin and treatment method of biosolids may markedly influence their characteristics. The legislation that controls the levels of heavy metal contents in biosolids and the maximum concentrations in soils is still controversial. In the long-term, heavy metal behavior after the and of biosolid application is still unknown. In soils, heavy metals may be adsorbed via specific or non-specific adsorption reactions. Iron oxides and organic matter are the most important soil constituents retaining heavy metals. The pH, CEC and the presence of competing ions also affect heavy metal adsorption and speciation in soils. In solution, heavy metals can be present either as free-ions or complexed with organic and inorganic ligands. Generally, free-ions are more relevant in environmental pollution studies since they are readily bioavailable. Some computer models can estimate heavy metal activity in solution and their ionic speciation. Thermodynamic data (thermodynamic stability constant), total metal and ligand concentrations are used by the GEOCHEM-PC program. This program allows studying heavy metal behavior in solution and the effect of changes in the conditions, such as pH and ionic strength and the application of organic and inorganic ligands caused by soil fertilization.


Jurnal Kimia ◽  
2020 ◽  
pp. 147
Author(s):  
A. T. Lema ◽  
J. M. Jacob

Nowadays, the use of formalin as a preservative in fish is often found in society. Besides, the consumption of fresh fish products containing heavy metals will potentially cause various diseases both short and long-term. The aims of this study were to assess the knowledge of society about formalin, detect the presence of formalin, and analyze the heavy metal content of Pb, Cd, and Hg in Yellow striped fish, Tuna and Mackerel fish. The qualitative detection was done using Schiff reagents, while the quantitative detection was done by using the Spectrophotometry based on the reaction of formaldehyde and Nash reagents. The results showed that 50 percent of society did not know about the use of formaldehyde and its characteristics in fish. The Qualitative testing on 9 samples found that 2 samples contained positive formalin, while 7 samples were negative. The quantitative test showed that the highest formalin content was found in Tuna and Mackerel fish with concentration of 3.36 ppm, and 1.26 ppm, respectively. Also, mercury was found as the highest concentration in fish roughly 1 to 1.60 ppm for those samples from three different markets.                                                                                                                                                 Keywords: formalin, heavy metal, fresh fish, market, Kupang city


Author(s):  

Based on long-term data, the seasonal variability of the content of heavy metal compounds in the water of the rivers of the foothills of the Central Caucasus – the Terek, Malka, Baksan, Ardon, Cherek, and Urukh – was estimated.Generalizing studies affecting the regional characteristics of the level of hazardous heavy metals in the river waters of the foothill zone of the Central Caucasus have not been carried out over many years. Therefore, the objective of the study was to assess the level of hazardous compounds of heavy metals (Cr, Ni, Mo, Mn, Zn, Pb) in the water of the Terek, Malka, Baksan, Ardon, Cherek and Urukh rivers at 6 observation points located in the foothill zone of the Central Caucasus, for the period from 2005 to 2018. In the analysis, the atomic absorption method using the MGA-915M electrothermal atomizer was used. The level of heavy metal compounds in river water was evaluated by such characteristics as the long-term average and median concentrations, the range of concentration fluctuations, and the frequency of exceeding the maximum permissible concentration. An analysis of long-term data for the period 2005-2018 on the study of the level of heavy metal compounds in the water of the Baksan, Malka, Urukh, Terek, Cherek and Ardon rivers in the foothill zone of the Central Caucasus shows that river water pollution to a greater extent occurs in summer rain flood . The revealed levels of heavy metal compounds in river water over the long-term period under study, as well as the frequency of exceeding the maximum permissible concentration, are illustrated by graphs. The results obtained may be relevant in the development of regional water quality indicators.


2006 ◽  
Vol 58 (2) ◽  
pp. 95-104 ◽  
Author(s):  
V. Vukojevic ◽  
M. Sabovljevic ◽  
Aneta Sabovljevic ◽  
Nevena Mihajlovic ◽  
Gordana Drazic ◽  
...  

In the present study, the deposition of three heavy metals (Cd, Co and Cr) in the county of Obrenovac (Serbia) is determined using four moss taxa (Bryum argenteum, Bryum capillare, Brachythecium sp. and Hypnum cupressiforme) as bioindicators. Distribution of average heavy metal content in all mosses in the county of Obrenovac is presented in maps, while long term atmospheric deposition (in the mosses Bryum argenteum and B. capillare) and short term atmospheric deposition (in the mosses Brachythecium sp. and Hypnum cupressiforme) are discussed and in tables. Areas of the highest contaminations are highlighted.


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