scholarly journals Preparation of Natural Ouw Clay-Chitosan Composite and Its Application as Lead and Cadmium Metal Adsorbent

2021 ◽  
Vol 9 (1) ◽  
pp. 15-20
Author(s):  
Catherina M. Bijang ◽  
M.F.J.D.P. Tanasale ◽  
Adhi G. Kelrey ◽  
Inda Ulfa Mansur ◽  
Thamrin Azis

This study aims to obtain the optimum ratio of Ouw Natural Clay  (LAO):Chitosan in the manufacture of chitosan-LAO composites. The composite will be used as an adsorbent for heavy metals Lead (Pb) and Cadmium (Cd). LAO-Chitosan composites were made with the ratio of LAO:Chitosan = 1.25:1, 2.5:1, 5:1. XRD and SEM were carried out for each composite. The performance as a Cd metal adsorbent was determined by calculating the adsorption capacity. Composites with a ratio of 1.25:1 have the best adsorption capacity. The performance as adsorbent for Cd metal was determined by calculating the absorbed Cd concentration. Maximum results are achieved by composites with a ratio of 5:1.

2020 ◽  
Vol 69 (2) ◽  
pp. 99-112 ◽  
Author(s):  
Hayder A. Alalwan ◽  
Mohammed A. Kadhom ◽  
Alaa H. Alminshid

Abstract The use of agricultural waste to remove heavy metals from wastewater has attracted much attention due to its economic advantages and high removal efficiency which is attributed to different functional groups. The sorption mechanism of biomass can consist of several steps including chemisorption, complexation, adsorption on surface, diffusion through pores, and ion exchange. Heavy metals were removed in different rates depending on the adsorbent and metal itself. For instance, coconut waste showed adsorption capacities of 263 and 285 mg/g in removing lead and cadmium ions, respectively. Also, black oak bark has adsorbed mercury in an adsorption capacity of 400 mg/g, while wheat brans adsorption capacity for chromium was 310 mg/g. The adsorption capacity is commonly calculated by Lagergren's first-order equation, the Redlich Peterson model, and the Brunauer–Emmett–Teller (BET) model. However, Langmuir and Freundlich models were intensively used to calculate the adsorbed amount by a unit weight of solid sorbents. This review article aims to present the recently available information on utilizing the biomass materials for heavy metals removal. Here, we highlight the increasing use of these materials due to their low cost, regeneration ability, high adsorption efficiency, and small chemical or biological sludge with a possibility of metal recovery.


2020 ◽  
Vol 99 (5) ◽  
pp. 478-482
Author(s):  
N. P. Setko ◽  
A. G. Setko ◽  
Ekaterina V. Bulycheva ◽  
A. V. Tyurin ◽  
E. Yu. Kalinina

Introduction. Changes in the body of children and adolescents aimed at adapting to environmental factors are determined by genetic polymorphism in xenobiotic biotransformation genes, determining the degree of susceptibility of the child’s body to pollutants, which is the basis of modern personalized preventive medicine when managing risks to the health of the child population under the influence of environmental factors. Material and methods. Trace elements, including heavy metals, lead and cadmium, were determined in the hair of 256 practically healthy teenagers by atomic absorption spectrophotometry. Depending on the level of content of the latter, two groups of adolescents were formed to determine six genes of the cytochrome P-450 family. Group 1 consisted of adolescents whose cadmium lead content exceeded the average Russian indices. The second group included adolescents whose heavy metals were above the level of average Russian standards. Results. Studies have shown that in adolescents of the 1st group, compared with the data of adolescents of the 2nd group, an increase in the number of carriers of two mutant alleles at the locus rs 1048943 (gene CYP1A1) is 3.08 times, rs 464621 (gene CYP1A1) is 1. 8 times; locus rs 2069522 (CYP1A2 gene) 3.63 times; locus rs 1799853 (CYP2C9 * 2 gene) 4.5 times; locus rs 1057910 (gene CYP2C9 * 3) 3.8 times and locus rs 2279343 (gene CYP2B6) 4.25 times. Moreover, carriers of two normal alleles in adolescents of the first group at the locus rs 1048943 (gene CYP1A1) were 5.14 times; locus rs 2279343 (CYP2B6 gene) was 6.5 fold less than among adolescents of the 2nd group; and at the locus rs 464621 (gene CYP1A1), rs 2069522 (gene CYP1A2), rs 1799853 (gene CYP2C9 * 2), rs 1057910 (gene CYP2C9 * 3) there were no carriers of normal homozygotes. Conclusion. Group 1 adolescents with heavy metal contamination of the body are carriers significantly in a greater number of pathological mutations in the genes of the cytochrome P-450 detoxification system in comparison with data from group 2 adolescents.


Author(s):  
Mahmud Mohammed Imam ◽  
Zahra Muhammad ◽  
Amina Zakari

In this research work the concentration of zinc, copper, lead, chromium, cadmium, and nickel in cow milk samples obtained from four different grazing areas   (kakuri, kudendan, malali, kawo) of Kaduna metropolis. The samples were digested by wet digestion technique .The trace element were determined using bulk scientific model VPG 210 model  Atomic Absorption Spectrophotometer (AAS).. The concentration of the determined heavy metal were The result revealed that Cr,  Ni and Cd were not detected in milk samples from Kawo, Malali  and Kudendan whereas lead (Pb) is detected in all samples and found to be above  the stipulated limits of recommended dietary allowance (NRC,1989) given as 0.02mg/day. Cu and Zn are essential elements needed by the body for proper metabolism and as such their deficiency or excess is very dangerous for human health. However, they were found in all samples and are within the recommended limits while Cd (2.13 – 3.15 mg/kg) in milk samples from Kakuri was found to be above such limit (0.5mg/day). Cow milk samples analyzed for heavy metals in this research work pose a threat of lead and cadmium toxicity due to their exposure to direct sources of air, water and plants in these grazing areas, thereby, resulting to a potential health risk to the consumers.


1999 ◽  
Vol 39 (2) ◽  
pp. 201-208 ◽  
Author(s):  
C. Dierkes ◽  
W. F. Geiger

Runoff from highways contains significant loads of heavy metals and hydrocarbons. According to German regulations, it should be infiltrated over embankments to support groundwater-recharge. To investigate the decontaminating effect of greened embankments, soil-monoliths from highways with high traffic densities were taken. Soils were analyzed to characterize the contamination in relation to distance and depth for lead, zinc, copper, cadmium, PAH and MOTH. Lysimeters were charged in the field and laboratory with highway runoff to study the effluents under defined conditions. Concentrations of pollutants in roadside soils depend on the age of embankments and traffic density. Highest concentrations were found in the upper 5 cm of the soil and within a distance of up to two metres from the street. Concentrations of most pollutants decreased rapidly with depth and distance. Lead and cadmium could not be detected in lysimeter effluent. Zinc and copper were found in concentrations that did not exceed drinking water quality limits.


1999 ◽  
Vol 40 (7) ◽  
pp. 109-116 ◽  
Author(s):  
M. H. Ansari ◽  
A. M. Deshkar ◽  
P. S. Kelkar ◽  
D. M. Dharmadhikari ◽  
M. Z. Hasan ◽  
...  

Steamed Hoof Powder (SHP), size < 53μ, was observed to have high adsorption capacity for Hg(II) with >95% removal from a solution containing 100 mg/L of Hg(II) with only 0.1% (W/V) concentration of SHP. The SHP has good settling properties and gives clear and odour free effluent. Studies indicate that pH values between 2 and 10 have no effect on the adsorption of Hg(II) on SHP. Light metal ions like Na+, K+, Ca2+ and Mg2+ up to concentrations of 500 mg/L and heavy metals like Cu2+, Zn2+, Cd2+, Co2+, Pb2+, Ni2+, Mn2+, Cr3+, Cr6+, Fe2+ and Fe3+ up to concentrations of 100 mg/L do not interfere with the adsorption process. Anions like sulphate, acetate and phosphate up to concentrations of 200 mg/L do not interfere. Chloride interferes in the adsorption process when Hg(II) concentration is above 9.7 mg/L. The adsorption equilibrium was established within two hours. Studies indicate that adsorption occurs on the surface sites of the adsorbent.


2021 ◽  
Vol 13 (15) ◽  
pp. 8552
Author(s):  
Vahid Alimohammadi ◽  
Mehdi Maghfouri ◽  
Delaram Nourmohammadi ◽  
Pejman Azarsa ◽  
Rishi Gupta ◽  
...  

Clean water is a vital need for all living creatures during their lifespan. However, contaminated stormwater is a major issue around the globe. A wide range of contaminants, including heavy metals, organic and inorganic impurities, has been discovered in stormwater. Some commonly utilized methods, such as biological, physical and chemical procedures, have been considered to overcome these issues. However, these current approaches result in moderate to low contaminant removal efficiencies for certain classes of contaminants. Of late, filtration and adsorption processes have become more featured in permeable concretes (PCs) for the treatment of stormwater. As nanoparticles have vast potential and unique characterizations, such as a higher surface area to cure polluted stormwater, employing them to improve permeable concretes’ capabilities in stormwater treatment systems is an effective way to increase filtration and adsorption mechanisms. The present study reviews the removal rate of different stormwater contaminants such as heavy metals, organic and other pollutants using nanoparticle-improved PC. The application of different kinds of nanomaterials in PC as porous media to investigate their influences on the properties of PC, including the permeability rate, compressive strength, adsorption capacity and mix design of such concrete, was also studied. The findings of this review show that different types of nanomaterials improve the removal efficiency, compressive strength and adsorption capacity and decrease the infiltration rate of PC during the stormwater treatment process. With regard to the lack of comprehensive investigation concerning the use of nanomaterials in PC to treat polluted stormwater runoff, this study reviews 242 published articles on the removal rate of different stormwater contaminants by using PC improved with nanoparticles.


RSC Advances ◽  
2020 ◽  
Vol 10 (68) ◽  
pp. 41482-41487
Author(s):  
Chen-Chen Zhu ◽  
Ning Bao ◽  
Xiao-Lei Huo

Children's shoes are potential sources of toxic heavy metals, especially for younger children.


BMJ Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. e039541
Author(s):  
Jun Ho Ji ◽  
Mi Hyeon Jin ◽  
Jung-Hun Kang ◽  
Soon Il Lee ◽  
Suee Lee ◽  
...  

ObjectivesTo investigate the associations between heavy metal exposure and serum ferritin levels, physical measurements and type 2 diabetes mellitus (DM).DesignA retrospective cohort study.SettingChangwon, the location of this study, is a Korean representative industrial city. Data were obtained from medical check-ups between 2002 and 2018.ParticipantsA total of 34 814 male subjects were included. Of them, 1035 subjects with lead exposure, 200 subjects with cadmium exposure and the 33 579 remaining were assigned to cohort A, cohort B and the control cohort, respectively. Data including personal history of alcohol and smoking, age, height, weight, the follow-up duration, haemoglobin A1c (HbA1c), fasting blood sugar (FBS), ferritin levels, and lead and cadmium levels within 1 year after exposure were collected.Primary outcome measureIn subjects without diabetes, changes in FBS and HbA1c were analysed through repeated tests at intervals of 1 year or longer after the occupational exposure to heavy metals.ResultsIn Cohort A, DM was diagnosed in 33 subjects. There was a significant difference in lead concentrations between the subjects diagnosed with DM and those without DM during the follow-up period (3.94±2.92 mg/dL vs 2.81±2.03 mg/dL, p=0.002). Simple exposure to heavy metals (lead and cadmium) was not associated with DM in Cox regression models (lead exposure (HR) 1.01, 95% CI: 0.58 to 1.77, p 0.971; cadmium exposure HR 1.48, 95% CI: 0.61 to 3.55, p=0.385). Annual changes in FBS according to lead concentration at the beginning of exposure showed a positive correlation (r=0.072, p=0.032).ConclusionOur findings demonstrated that simple occupational exposure to heavy metals lead and cadmium was not associated with the incidence of DM. However, lead concentrations at the beginning of the exposure might be an indicator of DM and glucose elevations.


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