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1.
Sci Rep ; 14(1): 11583, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773106

RESUMO

The present investigation explores the efficacy of green algae Ulva lactuca biochar-sulfur (GABS) modified with H2SO4 and NaHCO3 in adsorbing methylene blue (MB) dye from aqueous solutions. The impact of solution pH, contact duration, GABS dosage, and initial MB dye concentration on the adsorption process are all methodically investigated in this work. To obtain a thorough understanding of the adsorption dynamics, the study makes use of several kinetic models, including pseudo-first order and pseudo-second order models, in addition to isotherm models like Langmuir, Freundlich, Tempkin, and Dubinin-Radushkevich. The findings of the study reveal that the adsorption capacity at equilibrium (qe) reaches 303.78 mg/g for a GABS dose of 0.5 g/L and an initial MB dye concentration of 200 mg/L. Notably, the Langmuir isotherm model consistently fits the experimental data across different GABS doses, suggesting homogeneous adsorption onto a monolayer surface. The potential of GABS as an efficient adsorbent for the extraction of MB dye from aqueous solutions is highlighted by this discovery. The study's use of kinetic and isotherm models provides a robust framework for understanding the intricacies of MB adsorption onto GABS. By elucidating the impact of various variables on the adsorption process, the research contributes valuable insights that can inform the design of efficient wastewater treatment solutions. The comprehensive analysis presented in this study serves as a solid foundation for further research and development in the field of adsorption-based water treatment technologies.


Assuntos
Carvão Vegetal , Azul de Metileno , Ulva , Poluentes Químicos da Água , Purificação da Água , Azul de Metileno/química , Carvão Vegetal/química , Ulva/química , Adsorção , Poluentes Químicos da Água/química , Cinética , Purificação da Água/métodos , Enxofre/química , Concentração de Íons de Hidrogênio , Água/química , Algas Comestíveis
2.
Sci Rep ; 13(1): 18871, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37914771

RESUMO

This work examined the polycyclic aromatic hydrocarbons (PAHs) and n-alkanes quantities, sources, and hazards in sediments collected from the Egyptian Western Desert Oases namely: Dakhla, Kharga and Farafra oases. The n-alkane (C9-C20) residue concentrations have ranged from 0.66 to 2417.91 µg/g recorded for the three Oases. On the other hand, the total n-alkane ranged from 448.54 µg/g to 8442.60 µg/g. Higher carbon preference index (CPI) values (> 1.0) proposed that the natural sources could be the main contributor to n-alkanes in the Oases sediment. GC-MS/MS (selected reaction monitoring (SRM) method) was used for the determination of the ΣPAHs concentrations in the studied sediments. The ΣPAHs concentrations (ng/g, dry weight) in the studied three Oases varied from 10.18 to 790.14, 10.55 to 667.72, and from 38.27 to 362.77 for the Kharga, Dakhla and Farafra Oases, respectively. The higher molecular weight PAHs were the most abundant compounds in the collected samples. Assessing potential ecological and human health issues highlighted serious dangers for living things and people. All the investigated PAHs had cancer risk values between 1.43 × 10-4 and 1.64 × 10-1, this finding suggests that PAHs in the samples under study pose a moderate risk of cancer. The main sources of PAHs in this study are biomass, natural gas, and gasoline/diesel burning emissions.


Assuntos
Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Humanos , Egito , Espectrometria de Massas em Tandem , Hidrocarbonetos , Hidrocarbonetos Policíclicos Aromáticos/análise , Alcanos/análise , Medição de Risco , Sedimentos Geológicos/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , China
3.
Toxicol Res ; 39(3): 517-531, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37398572

RESUMO

Chronic exposure to Poly aromatic hydrocarbons (PAHs) may be associated with adverse pregnancy outcomes. Disruption of hormonal and redox balance by toxic PAH metabolites may interfere with successful pregnancy leading to miscarriage. The association of exposure to PAH contaminated mussel via the dietary route with perturbations in reproductive hormones, biomarkers of oxidative stress, and PAH metabolites were assessed in women with recurrent pregnancy loss (RPL). Furthermore, an analysis of the concentration of PAHs in environmentally relevant bivalve animals was performed to preliminary get insights into the levels of these pollutants in the environment. Seventy-six women (20-35 years) were categorized into 18 fertile women without RPL (control), and Groups I, II, and III comprising 24, 18, and 16 women with RPL (2, 3, and > 3 abortions respectively) were studied. Whole blood samples were collected for the estimation of malondialdehyde (MDA), catalase, reduced glutathione (GSH), glutathione-S-transferase (GST), progesterone (P4), follicle-stimulating hormone (FSH), benzo[a]pyren-7,8-dihydrodiol-9,10-epoxide-albumin adduct (BPDE-albumin) and urine for α-naphthol and ß-naphthol. Two species of mussel Donax trunculus and Andar aduloii samples were collected for the estimation of 16 priority PAHs. The concentration of PAHs exceeding the maximum limits was observed in the two species of mussels studied. Higher levels of BPDE-albumin, MDA, GST, α and ß-naphthol and lower GSH, catalase, FSH, and P4 were observed in women with RPL (Groups I-III) compared to controls (p = < 0.001). Negative associations were observed between BPDE-albumin and catalase (r = - 0.276, p = 0.036), and GSH (r = - 0.331, p = - 0.011) only in women with RPL. Collectively, our findings indicate a possible association of chronic PAH accumulation with recurrent pregnancy loss in women. Graphical abstract: High PAH exposure in pregnant women is associated with 10-epoxide-albumin adduct formation and high MDA levels in their sera. On the other hand, PAH exposure in those women led to a decrease in their GSH, catalase, P4, and FSH sera levels. These findings indicate that PAH exposure can exert different physiological effects in pregnant women leading to a high level of abortion in those women.

4.
Mar Pollut Bull ; 194(Pt B): 115262, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37467685

RESUMO

The variations in the levels of n-alkanes and Polycyclic Aromatic Hydrocarbons (PAHs) in the sediment of the Nile Delta coast and extended to Bardaweel Lagoon along the Mediterranean were investigated during September 2021. The total n-alkane concentrations in the sediment samples ranged from 18.85 to 164.37 µg/g with an average value of 51.98 ± 17.49 µg/g. Similarly, the ΣPAHs concentrations ranged between 4.55 and 207.48 ng/g with an average of 27.89 ± 49.82 ng/g. The carbon preference index (CPI) values were in the 0.21 to 1.39 range, indicating variations in the sources of n-alkane at the analyzed locations. The mean carbon number (MCN) values ranged from 7.41 to 15.47, with an average of 13.34 ± 1.69. The levels of both low and high molecular weight PAHs were lower than the median and low effective range values (ERM and ERL). The computed total TEQ value varied from 0.102 to 4.129 ng/g in the sediment samples under investigation.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Alcanos/análise , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Monitoramento Ambiental
5.
Mar Pollut Bull ; 193: 115236, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37418808

RESUMO

This preliminary investigation aimed to detect concentrations of chlorinated pesticides and PCBs in 40 sediment samples from three desert oases located in Kharga, Dakhla and Farafra in western Egypt. The residues of 18 PCBs and 16 chlorinated pesticides were measured by GC-MS/MS (SRM) method. The results showed that PCBs and pesticides were present in all studied samples. The concentrations of individual PCBs ranged from undetected to 3.99 ng/g dw in all these sediment samples. The total residue of pesticides (ng/g, dry weight) in sediment samples also varied from 5.18 to 25.92, 5.41 to 29.49, and 5.93 to 24.19 ng/g dw for the Kharga, Dakhla and Farafra Oases, respectively. The concentrations of PCBs and chlorinated pesticides detected in these oasis sediments were lower than that reported for other worldwide locations. According to the recorded concentrations in this baseline study of PCBs and total DDTs, the results revealed the minimal risks to organisms and people in the studied area according to the Effects Range-Low (ERL) and Effects Range-Median (ERM) guideline values.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Poluentes Químicos da Água , Humanos , Bifenilos Policlorados/análise , Praguicidas/análise , Hidrocarbonetos Clorados/análise , Egito , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química , Monitoramento Ambiental
6.
Sci Rep ; 13(1): 5910, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041227

RESUMO

In this study, cellulose hydrogels were simply fabricated by the chemical dissolution method using LiCl/dimethylacetamide as a new method, and the hydrogel produced was investigated for removing Direct Blue 86 (DB86) dye from the aquatic environment. The produced cellulose hydrogel (CAH) was characterized by FTIR, XRD, SEM, and TGA analyses. The removal efficiency of DB86 dye using CAH was achieved via a batch equilibrium process. The impact of pH, time of contact, CAH dosage, starting concentration of DB86 dye, and absorption temperature were scanned. The optimum pH for absorption of DB86 dye was determined to be 2. The absorption results obtained were scanned by Langmuir (LIM), Temkin (TIM), Freundlich (FIM), and Dubinin-Radushkevich (DRIM) isotherm models (IMs) and chi-square error (X2) function used to identify the best-fit IMs. The CAH had 53.76 mg/g as a maximum absorption capacity (Qm) calculated from the LIM plot. The TIM was the best fitted to the CAH absorption results. Kinetic absorption results were investigated by pseudo-first-order (PFOM), Elovich (EM), pseudo-second-order (PSOM), film diffusion (FDM), and intraparticle diffusion (IPDM) models. A PSOM with a high R2 (> 0.99) accounted for the majority of the control over the absorption rate. The findings indicate that CAH can potentially remove the DB86 dye from wastewater.

7.
Microb Cell Fact ; 22(1): 78, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37085834

RESUMO

BACKGROUND: Metal oxide nanoparticles (NPs) are becoming valuable due to their novel applications. The green synthesis of TiO2 NPs is more popular as a flexible and eco-friendly method compared to traditional chemical synthesis methods. TiO2 NPs are the most commonly used semiconductor in dye-sensitized solar cells (DSSCs). RESULTS: The biogenic TiO2 NPs were produced extracellularly by the marine halophilic bacterium Halomonas sp. RAM2. Response surface methodology (RSM) was used to optimize the biosynthesis process, resulting in a starting TiO2 concentration of 0.031 M and a pH of 5 for 92 min (⁓15 nm). TiO2 NPs were well-characterized after the calcination process at different temperatures of 500, 600, 700 and 800 °C. Anatase TiO2 NPs (calcined at 500 °C) with a smaller surface area and a wider bandgap were nominated for use in natural dye-sensitized solar cells (NDSSCs). The natural dye used as a photosensitizer is a mixture of three carotenoids extracted from the marine bacterium Kocuria sp. RAM1. NDSSCs were evaluated under standard illumination. After optimization of the counter electrode, NDSSCBio(10) (10 layers) demonstrated the highest photoelectric conversion efficiency (η) of 0.44%, which was almost as good as NDSSCP25 (0.55%). CONCLUSION: The obtained results confirmed the successful green synthesis of TiO2 NPs and suggested a novel use in combination with bacterial carotenoids in DSSC fabrication, which represents an initial step for further efficiency enhancement studies.


Assuntos
Halomonas , Nanopartículas Metálicas , Energia Solar , Titânio , Corantes
8.
Sci Rep ; 13(1): 2276, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755140

RESUMO

This attempt has been made to synthesize the cellulose di-acetate in a solvent-free acetylation system of cotton Giza 86 cellulose with Ac2O (200 and 300 ml) in the presence of NiCl2.6HO (1.0, 1.5 and 2.0 g) as an effectively available and new catalyst by the conventional reflux and microwave irradiation methods. This study also illustrates the preparation of a dialysis membrane made from a cellulose di-acetate-dichloromethane-methanol-polyethylene glycol (MW: 200) casting solution. The microwave irradiation method for the synthesis of cellulose di-acetate showed excellent yields and short reaction time, which is an important feature of this method. The impact of the two methods on the cellulose di-acetate formation and its used in the dialysis membrane formulations was studied. The experimental degree of substitution of the prepared cellulose di-acetate values (DS = 2.00-2.7) showed an agreement with the calculated values by FTIR and 1H-NMR analysis methods. The formation of cellulose di-acetate with percentage yields varied from 62.85 to 89.85%. The applicability of the prepared membrane in dialysis operation was evaluated in terms of urea clearance, rejection of Bovine Serum Albumin (BSA) and flux of pure water. Characterization of cellulose di-acetate was achieved through 1H-NMR, FTIR, TGA, and BET analyses. The CA-PEG blend membrane was examined by contact angle measurement, porosity, and water uptake of the membrane. The cellulose acetate membrane surface morphology was determined using SEM. It is observable that the fabricated CA-PEG blend membrane from synthesized cellulose di-acetate by using Nickel chloride as a catalyst is showing remarkable rejection of BSA and urea clearance up to 100 and 67.2%, respectively. The present work is promising and applicable in dialysis membranes.

9.
Sci Rep ; 12(1): 18203, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307503

RESUMO

Marine pigmented bacteria are a promising natural source of carotenoids. Kocuria sp. RAM1 was isolated from the Red Sea Bohadschia graeffei collected from Marsa Alam, Egypt, and used for carotenoids production. The extracted carotenoids were purified by thin-layer chromatography (TLC). The characteristic UV absorbance of the three purified fractions gave us an inkling of what the purified pigments were. The chemical structures were confirmed by nuclear magnetic resonance spectroscopy (NMR) and LC-ESI-QTOF-MS/MS. The three different red pigments were identified as two C50-carotenoids, namely bisanhydrobacterioruberin and trisanhydrobacterioruberin, in addition to 3,4,3',4'-Tetrahydrospirilloxanthin (C42-carotenoids). Kocuria sp. RAM1 carotenoids were investigated for multiple activities, including antimicrobial, anti-inflammatory, antioxidant, anti-HSV-1, anticancer, antidiabetic and wound healing. These new observations suggest that Kocuria sp. RAM1 carotenoids can be used as a distinctive natural pigment with potent properties.


Assuntos
Carotenoides , Micrococcaceae , Carotenoides/química , Espectrometria de Massas em Tandem , Bactérias , Cromatografia em Camada Fina
10.
J Health Pollut ; 9(21): 190309, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30931169

RESUMO

BACKGROUND: Biological mechanisms contribute to the relationship between polycyclic aromatic hydrocarbon (PAH) exposure and infertility in males by altering semen quality. OBJECTIVES: The aim of the present study was to evaluate the impact of PAHs on male infertility using the sperm chromatin dispersion test (Halo sperm assay). METHODS: Sixty-six (66) infertile males under 45 years of age were examined for the determination of urinary metabolite and oxidative stress by measuring lipid peroxidation and antioxidant activity of glutathione and glutathione-s-transferase, as well as hormonal activity of follicle stimulating hormone (FSH), testosterone and prolactin and semen quality. RESULTS: There was an increased level of urinary metabolite of 1-hydroxy pyrene, 1-hydroxy naphthalene and 2-hydroxy naphthalene in the urine of the infertile group. In addition, elevated concentrations of malondialdehyde coincided with a decreased level of antioxidants, leading to oxidative stress in the infertile group. Semen samples showed 30% sperm deoxyribonucleic acid (DNA) fragmentation. CONCLUSIONS: The data provide strong evidence of a statistical threshold for semen samples containing 30% sperm DNA fragmentation resulting in a reduced level of pregnancy success. PARTICIPANT CONSENT: Obtained. ETHICS APPROVAL: Study approval was given by the ethics committee of Alexandria University (United States Department of Health and Human Services, institutional review board registration (IRB), IORG0008812 Medical Research Institute, expires 4/8/2019, OMB No: 0990-0279). COMPETING INTERESTS: The authors declare no competing financial interests.

11.
J Health Pollut ; 8(18): 180608, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30524857

RESUMO

BACKGROUND: Metals pollution plays an important role in the regulation of gene expression through interference with signal transduction pathways which are important for cell bioactivity. OBJECTIVES: The present study was conducted to estimate metallothionein levels in mussels as a biomarker of exposure to heavy metals in order to monitor the pollution of Abu Qir Bay, Egypt (El-Maadiya region) and to evaluate the impact of heavy metals on human health by examining insulin-like growth factor II (IGF-2) gene expression in peripheral blood mononuclear cells. METHODS: One hundred and forty mussel samples (Andara dulofii) were collected from Abu-Qir Bay, stored in bags, preserved in an ice box, and then transported to the laboratory to acclimatize at 20°C for three days in ethylene diamine tetra acetic acid (EDTA)-free synthetic sea water to determine the presence of metallothionein and five other metals (cadmium (Cd), lead (Pb), chromium (Cr), copper (Cu) and zinc (Zn)). RESULTS: Results showed that mussels collected from the study area contained a measurable amount of metallothionein. In addition, results revealed an increased level of malondialdehyde coinciding with a decreased level of antioxidants, leading to oxidative stress in local fishermen. CONCLUSIONS: The present data demonstrated a significant increase in the gene expression of IGF-2 and a positive correlation between IGF-2 gene expression and the enzymatic activity of glutathione peroxidase in male subjects. PARTICIPANT CONSENT: Obtained. ETHICS APPROVAL: Written consent was provided by the study participants and study approval was given by the ethics committee of Alexandria University (US Department of Health and Human Services, Registration of an Institutional Review Board, IORG0008812 Medical Research Institute, Expires 4/8/2019, OMB No:0990-0279). COMPETING INTERESTS: The authors declare no competing financial interests.

12.
Chemosphere ; 165: 369-380, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27668715

RESUMO

Zn, Cu, Ni, V, Al, Pb, Cd, Hg, lipid and water contents were determined in the soft tissues of different shellfish species collected along the Red Sea shoreline. Metal contents showed a descending order of Zn > Cu > Ni > Al > V > Pb > Cd > Hg. The leachable concentrations found in the sediments gathered from the studied locations gave another descending order: Al > Zn > Ni > Pb > V > Cu > Cd. The determined leachable heavy metal contents in the sediment did not exceed the NOAA and CCME (Anonymous 1999) sediment quality guidelines. Accordingly, the sediments along the Egyptian Red Sea area did not pose any adverse impacts on the biological life. According to the hazard quotient (HQ) calculations for heavy metal contents in the soft tissue of shellfish, mercury did not pose any risk on human health; whereas, the other determined heavy metals gave HQ values of 1 < HQ < 10 and showed a possibility of risk on the long term. Cu is above the desirable levels in mussels. The RQ calculations of toddlers and adults reflected that Cu was the only heavy metal that had an adverse effect on toddlers' health. Based on the human organizations (EPA, BOE, MAFF, and NHMRC) that proposed safety concentrations of heavy metals, the studied shellfish were somewhat safe for human consumption.


Assuntos
Monitoramento Ambiental , Contaminação de Alimentos/análise , Sedimentos Geológicos/química , Metais Pesados/análise , Alimentos Marinhos/análise , Frutos do Mar/análise , Poluentes Químicos da Água/análise , Egito , Humanos , Oceano Índico , Mercúrio/análise , Medição de Risco
13.
Carbohydr Polym ; 151: 1058-1067, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27474655

RESUMO

This research demonstrates the effect of ZnCl2 as a catalyst on the esterification of commercial cotton cellulose using acetic anhydride in order to obtain di- and tri-cellulose acetates under microwave irradiation. It was discovered that microwave irradiation significantly increased the yield and reduced the reaction time. It was found that the maximum yield for cellulose triacetates was 95.83% under the reaction conditions that were as follows: 3min reaction time, 200mg of ZnCl2 catalyst and 20ml of Ac2O for 5g cellulose. However, the cellulose acetate obtained in this manner had the highest DS (2.87). The cellulose di-acetate was produced with the maximum yield of 89.97% and with the highest DS (2.69) using 25ml Ac2O, 200mg of ZnCl2 for 5g cellulose and in 3min reaction time. The effect of some factors such as the amount of used catalyst, the quantity of acetic acid anhydride and the reaction time of the esterification process have been investigated. The production of di- and tri-cellulose acetate and the degree of substitution were confirmed using Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR). The thermal stability was investigated using thermo gravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The molecular weight and the degree of polymerization were obtained using Gel Permeation Chromatography (GPC). The analysis confirmed the successful synthesis of di- and tri-cellulose acetate without degradation during the reaction; these results were found to be in contrast to some recent studies. The present study reveals that ZnCl2 is a new catalyst; it is effective as well as inexpensive and is a low toxicity catalyst for usage in cellulose esterification.


Assuntos
Celulose/análogos & derivados , Cloretos/química , Micro-Ondas , Compostos de Zinco/química , Acetilação , Catálise , Celulose/química , Gossypium/química , Solventes/química
14.
J Health Pollut ; 6(12): 50-60, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30524805

RESUMO

BACKGROUND: When heavy metals accumulate in air, soil, and water, the risk of human exposure increases among industrial workers, as well as in people living near polluted areas. Heavy metals adversely affect a variety of bodily systems such as the cardiovascular, respiratory, endocrine, immune, and reproductive systems. In addition, long-term exposure and accumulation of heavy metals in the body may disturb oxidative stress genes and thus increase the susceptibility to various diseases. OBJECTIVES: The aim of this study is to estimate the metallothionein concentration in both mussel samples from Abu Qir Bay, Egypt and the blood of local fishermen as a biomarker of exposure to metal pollution. METHODS: Levels of metallothionein and heavy metals were measured in mussels. Blood levels of metallothionein and heavy metals of local fishermen were measured and compared with a control group. The effect of heavy metal exposure on oxidative stress status was investigated through the determination of malondialdehyde (MDA), catalase and glutathione content. RESULTS: The results of this study showed high concentrations of metallothionein in mussels and in fishermen's blood, accompanied by high concentrations of metals such as cadmium (Cd), copper (Cu), lead (Pb), chromium (Cr), and zinc (Zn). At the same time, a significant decrease in glutathione content and catalase enzyme activity was associated with a significant increase in the malondialdehyde concentrations in sera of fishermen. CONCLUSIONS: The present study found that the El Maadiya region is polluted with heavy metals, inducing oxidative stress in fishermen in the vicinity. These results reveal the necessity of further environmental monitoring in the study area in order to evaluate other types of pollutants and their effects on human health.

15.
Carbohydr Polym ; 130: 41-8, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26076599

RESUMO

This research discusses the acetylation of cotton cellulose with acetic anhydride without solvents. The acetylation was done in the presence of different amounts of N-Iodosuccinimide (NIS) as a catalyst; this took place under mild reaction conditions. The extent of acetylation was measured by the weight percent gain (WPG) that varied from 24.71 to 71.83%. Cotton cellulose acetates, with the degree of substitution (DS) that ranged from 0.89 to 2.84, were prepared in one step. The cellulose triacetate, with a degree of substitution (DS) 2.84, was obtained. The WPG and DS were easily controlled by changing the reaction duration (1-5h), and the concentration of the catalyst (0.05 g, 0.075 g and 0.10 g for 1g of cellulose) in 25 ml of acetic anhydride. NIS was recognized as a novel and more successful catalyst for the acetylation of hydroxyl groups in cotton cellulose. Formation of the acetates and the calculation of the degree of substitution were performed by FT-IR, Raman, and (1)H NMR.


Assuntos
Celulose/análogos & derivados , Gossypium/química , Succinimidas/química , Acetilação , Catálise , Celulose/síntese química , Celulose/química , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termogravimetria
16.
Artigo em Inglês | MEDLINE | ID: mdl-23802155

RESUMO

Canned fish (tuna and sardine) of different geographical regions were collected randomly from supermarkets and were analyzed for heavy metal contents (Hg, Cd and Pb) polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and pesticides. Canned fish samples (two brands of sardines, six brands of tuna) that were purchased from Egyptian cities between 2009 and 2010, represent four countries (Morocco, Republic of Yemen, Indonesia and Thailand). Health risks on humans via dietary intake of seafood were assessed by the target hazard quotients (THQs), potential non-carcinogenic and carcinogenic effects. The contents of trace metals in canned tuna and canned sardines were found as: 0.149-0.218 µg/g for Cd; 0.312-0.937 µg/g for Pb and 0.053-0.022 µg/g for Hg. Canned sardines fluctuated between 0.55 and 1.82, 1.08 and 1.64, 11.91 and 26.24 ng/g for total HCHs, Total cyclodienes and DDTs respectively while the corresponding concentrations in canned tuna were 0.24-1.85, 0.24-1‥85 and 6.56-49.73 ng/g, respectively. Total PCBs fluctuated between 21.75 and 55.10 for canned sardines and 8.56-208.11 ng/g for canned tuna. On the other hand the total PAHs fluctuated between 0.006-9.775 and 1.556-2.686 ng/g for tuna and sardines. From the human health point of view, there is no adverse health effect for both PAHs and heavy metals content on consumers.


Assuntos
Poluentes Ambientais/análise , Peixes , Contaminação de Alimentos/análise , Animais , Egito , Monitoramento Ambiental , Conservação de Alimentos , Humanos , Metais Pesados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco
17.
Environ Monit Assess ; 185(6): 4835-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23054273

RESUMO

The analyses of environmentally persistent pollutants like polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) isomers, and dichlorodiphenyltrichloroethane (DDT) and its metabolites in surficial sediment samples collected from 17 locations along with the coast of the Red Sea in Egypt were carried out using gas chromatography-mass spectrometry. Several potential organic contaminants from agricultural (e.g., DDT and its breakdown products, lindane, endrin, dieldrin, and endosulfan) and industrial (PCBs) sources were measured. The levels of 20 organochlorine pesticides (OCPs) and ten PCB congeners in sediment collected from 17 stations along ~1,200 km were investigated. Concentrations of PCBs, HCHs, DDTs, and cyclodienes ranged from 0.40 to 6.17, 0.01 to 0.09, n.d. to 0.46, and 0.08 to 0.90 ppb dry weight. Two statistical programs were applied on the data (principal component analysis, PCA, and cluster analysis, CA), and it was concluded that it is impossible to predict the distribution patterns of the OCPs in a contaminated area. Risk assessment of the organochlorines contaminated in the sediments of the studied area was investigated.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Clorados/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Oceano Índico , Praguicidas/análise , Medição de Risco , Água do Mar/química
18.
Environ Monit Assess ; 185(7): 6089-99, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23212555

RESUMO

This study pointed to the assessment of the chemical composition (F, Ca, Mg, Na, K, Fe, Mn, Zn, Cu, Ni, Co, Cr, Cd, and carbohydrate) of different marine seaweeds (red, green, and brown) from the Egyptian Mediterranean Sea coast. The results showed that green seaweeds supplied better calcium sources than the red and brown ones. Also, red and brown seaweeds showed higher averages of Na and K than that in green species and these seaweeds could play an important role in the electrolyte balance in humans. On the other hand, green seaweeds gave the highest average carbohydrate concentration; thus, these green species could be used as a source of polysaccharides. Ion quotient values for almost seaweed species were between 1.4 and 4.0, so they can reduce hypertension, preeclampsia, and heart disease in human beings. Interestingly, the calculated hazard quotient of elements was below 1. Accordingly, these seaweed species were of high quality and safety and might be used in the field of nutrition.


Assuntos
Alga Marinha/química , Poluentes Químicos da Água/análise , Egito , Monitoramento Ambiental , Mar Mediterrâneo , Medição de Risco
19.
J Hazard Mater ; 165(1-3): 100-10, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19013711

RESUMO

The purpose of this study is to suggest an efficient process, which does not require a huge investment for the removal of direct dye from wastewater. Activated carbon developed from agricultural waste material was characterized and utilized for the removal of Direct Navy Blue 106 (DNB-106) from wastewater. Systematic studies on DNB-106 adsorption equilibrium and kinetics by low-cost activated carbons were carried out. Adsorption studies were carried out at different initial concentrations of DNB-106 (50, 75, 100, 125 and 150 mg l(-1)), contact time (5-180 min), pH (2.0, 3.0, 4.7, 6.3, 7.2, 8.0, 10.3 and 12.7) and sorbent doses (2.0, 4.0 and 6.0 g l(-1)). Both Langmuir and Freundlich models fitted the adsorption data quite reasonably (R(2)>97). The maximum adsorption capacity was 107.53 mg g(-1) for 150 mg l(-1) of DNB-106 concentration and 2 g l(-1) carbon concentration. Various mechanisms were established for DNB-106 adsorption on developed adsorbents. The kinetic studies were conducted to delineate the effect of initial dye concentration, contact time and solid to liquid concentration. The developed carbon might be successfully used for the removal of DNB-106 from liquid industrial wastes.


Assuntos
Compostos Azo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Lythraceae , Estruturas Vegetais , Indústria Têxtil
20.
J Hazard Mater ; 161(1): 102-10, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18455301

RESUMO

The use of low-cost, easy obtained, high efficiency and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from orange peel for the removal of direct blue-86 (DB-86) (Direct Fast Turquoise Blue GL) dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were studied. The results showed that as the amount of the adsorbent increased, the percentage of dye removal increased accordingly. Optimum pH value for dye adsorption was determined as approximately 2.0. Maximum dye was sequestered within 30min after the beginning for every experiment. The adsorption of direct blue-86 followed a pseudo-second-order rate equation and fit well Langmuir, Tempkin and Dubinin-Radushkevich (D-R) equations better than Freundlich and Redlich-Peterson equations. The maximum removal of direct blue-86 was obtained at pH 2 as 92% for adsorbent dose of 6gL(-1) and 100mgL(-1) initial dye concentration at room temperature. The maximum adsorption capacity obtained from Langmuir equation was 33.78mgg(-1). Furthermore, adsorption kinetics of DB-86 was studied and the rate of adsorption was found to conform to pseudo-second-order kinetics with a good correlation (R2>0.99) with intraparticle diffusion as one of the rate determining steps. Activated carbon developed from orange peel can be attractive options for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater show better removal percentage of DB-86.


Assuntos
Citrus sinensis/anatomia & histologia , Citrus sinensis/química , Corantes/química , Corantes/isolamento & purificação , Difusão , Concentração de Íons de Hidrogênio , Cinética , Modelos Químicos , Peso Molecular , Soluções , Fatores de Tempo
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