116 research outputs found
Heavy metals (Cd, Cu, Ni and Pb) content in two fish species of Persian Gulf in Bushehr Port, Iran
Heavy metal (HMs) pollution of aquatic environment has become a great concern in recent years. In this study, cadmium (Cd), copper (Cu), nickel (Ni) and lead (Pb) levels were determined in muscle and skin of two important consumed fishes (Indo-Pacific king mackerel and Tigertooth croaker) in Bushehr Province in the Southwestern of Iran. Heavy metal concentrations were analyzed by using inductively coupled plasma (ICP). The mean contents of metal, expressed in mg/kg wet weight, varied from 0.17 to 0.26 for Cd, 1.25 to 1.84 for Cu, 0.6 to 0.84 for Ni and 0.31 to 0.7 for Pb. Results showed that the highest and lowest contents of heavy metals in muscle and skin of both fish samples were related to Cu and Cd concentration, respectively, and heavy metal contents in both skin fish samples and muscle of Tigertooth croaker were found to decrease in sequence as Cu>Pb>Ni>Cd.Key words: Heavy metal, fish, Bushehr, Iran
Retraction Note: Ambient particulate matter concentration levels of Ahvaz, Iran, in 2017 (Environmental Geochemistry and Health, (2019), 41, 2, (841-849), 10.1007/s10653-018-0182-0)
The Editor-in-Chief has retracted this article because it contains material that substantially overlaps with another published article [1]. Sina Dobaradaran agrees to this retraction. Gholamreza Goudarzi, Sahar Geravandi, and Mohammad Javad Mohammadi do not agree to this retraction. Nadali Alavi, Ahmad Reza Yari, Farzaneh Aslanpour Alamdari, Majid Farhadi, Hamed Biglari, Maryam Dastoorpour, and Bayram Hashemzadeh have not responded to any correspondence from the publisher about this retraction
Catalytic decomposition of 2-chlorophenol using an ultrasonic-assisted Fe3O4-TiO2@MWCNT system: Influence factors, pathway and mechanism study.
As a reusable sonocatalyst, magnetically separable Fe3O4-TiO2@MWCNT (FMT) was synthesized by an ultrasound-assisted wet impregnation method and was evaluated in the removal of 2-chlorophenol (2CP). Physical and chemical properties of the catalyst composite materials were investigated by all catalysts were systematically characterized using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Analysis (EDX), Dynamic light scattering (DLS), and N2-physisorption. The efficiency and kinetics of 2CP removal by FMT-assisted sonocatalysis (FMT-US) was systematically investigated under various operational parameters i.e. pH, FMT and 2CP concentration, temperature and ultrasonic power. The results indicated that 0.4gL-1 FMT dosage, pH 5, temperature of 35°C as well as 50 w ultrasound power are the most favorable conditions for the degradation of the 2CP. Furthermore, both of the superoxide and hydroxyl radicals were produced in the reaction, however, superoxide radicals were assumed to be the dominating reactive species for the 2CP degradation, according to the scavenging tests and electron paramagnetic resonance tests. Moreover, the FMT catalyst exhibited a high reusability and stability in the US/FMT system during the five repetitive experiments. The intermediate products were identified by GC-MS, thereby a possible degradation pathway is proposed. The chemical oxygen demand (COD) and corresponding total organic carbon (TOC) removal efficiencies were 64.9% and 56.7%, respectively. Finally, toxicity tests showed that the toxicity of the solution increased during the first 5min and then decreased significantly with the progress of the oxidation. The mechanisms of ultrasound irritation enhanced FMT activation were also proposed.
Copyright © 2017 Elsevier Inc. All rights reserved
Waste sludge from shipping docks as a catalyst to remove amoxicillin in water with hydrogen peroxide and ultrasound
The waste sludge from shipping docks contains important elements that can be used as a catalyst after proper processing. The purpose of this study was to remove of amoxicillin (AMX) from the aquatic environment using waste sludge from shipping docks as catalyst in the presence of hydrogen peroxide/ultrasound waves. The catalyst was produced by treating waste sludge at 400 °C for 2 h. N2 adsorption, SEM, XRD, XRF, and FTIR techniques characterized the structural and physical properties of the catalyst. The BET-specific surface area of the catalyst reduced after AMX removal from 4.4 m2/g to 3.6 m2/g. To determine the optimal removal conditions, the parameters of the design of experiments were pH (5–9), contaminant concentration (5–100 mg/L), catalyst dosage (0.5–6 g/L), and concentration of hydrogen peroxide (10–100 mM). The maximum removal of AMX (98%) was obtained in the catalyst/hydrogen peroxide/ultrasound system at pH 5, catalyst dose of 4.5 g/L, H2O2 concentration of 50 mM, AMX concentration of 5 mg/L, and contact time of 60 min. The kinetics of removal of AMX from urine (k = 0.026 1/min), hospital wastewater (k = 0.021 1/min), and distilled water (k = 0.067 1/min) followed a first-order kinetic model (R2>0.91). The catalyst was reused up to 8 times and the AMX removal decreased to 45% in the last use. The byproducts and reaction pathway of AMX degradation were also investigated. The results clearly show that to achieve high pollutant removal rate the H2O2/ultrasound and catalyst/ultrasound synergy plays a key role
Multi-walled carbon nanotubes modified with iron oxide and silver nanoparticles (MWCNT-Fe<inf>3</inf>O<inf>4</inf>/Ag) as a novel adsorbent for determining PAEs in carbonated soft drinks using magnetic SPE-GC/MS method
The synthesis of compounds with an excellent adsorption capability plays an essential role to remove contaminants such as phthalic acid esters (PAEs) with potential carcinogenic characteristics from different food products. In this context, for the first time, a novel adsorbent (MWCNT-Fe3O4/Ag) was synthesized by using iron (magnetic agent), and silver (catalytic and surface enhancer agent) to further approach in a magnetic SPE-GC/MS method for determining of PAEs in carbonated soft drink samples. The limit of detection (LOD) and limit of quantification (LOQ) values of MSPE-GC/MS were determined in six PAEs as a range of 10.8–22.5 and 36–75 ng/L, respectively. Also, the calibration curves of PAEs were linear (R2 = 0.9981–0.9995) over the concentration level of 10.000 ng/L and the recoveries of the six PAEs were ranging from 96.60% to 109.22% with the RSDs less than 8%. Moreover, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray diffraction (XRD), vibrating sample magnetometry (VSM) and transmission electron microscopy analyses (TEM) were utilized to characterize the produced MWCNT-Fe3O4/Ag. Based on the findings, the surface of MWCNT is relatively uniform, which became coarser after loading with Fe3O4/Ag particles. Also, EDX spectrum showed the carbon (C), iron (Fe), oxygen (O), Ag and copper (Cu) are the main components of synthesized MWCNTs-Fe3O4/Ag. The successful adhesion of Fe3O4/Ag on the texture of MWCNTs using a co-precipitation method was confirmed by XRD and FT-IR assays. Additionally, excellent crystallinity and clear lattice nanocrystals fringes of prepared MWCNT-Fe3O4/Ag was demonstrated by TEM analysis. Based on the obtained VSM images, the prepared sorbent (MWCNT-Fe3O4/Ag) has the good magnetic performance for magnetic separation and extraction processes. It was concluded that the synthesized MWCNT-Fe3O4/Ag could be used as an efficient adsorbent for determining contaminants such as PAEs in different beverage samples. © 201
Load characteristics, in vitro bioaccessibility and health risk assessment of PM2.5–bounded heavy metals in indoor air of waterpipe and/ or cigarette cafes compared to smoking-free cafes
Samples of PM2.5 particulates were collected from indoor air of 36 cafés, 14 cafés in which only water pipe (WS) was used, eight in which only cigarette was smoked (CC), six in which both waterpipe and cigarette were smoked (WCC), and eight cafés in which no smoking occurred (SFC) in Tehran. After that, the concentration of lead (Pb), cadmium (Cd), nickel(Ni), and chromium (Cr) was examined by atomic absorption spectrophotometer (AAS) (GF 5000, Australia). The results indicated that the ƩMetal concentration (Mean ±SD) in WCC, WC, CC, and SFC cafés were 1118.5±50.42, 663.64±40.79, 425.57±17.55, and 79.02±5.13 ng/m3, respectively. The mean bioaccessibility of Pb, Cr, Ni, and Cd was obtained as 39.7, 31.4, 7.35, and 74.6, respectively. The results of risk assessment indicated that exposure to heavy metals in the indoor air of smoking cafés of Tehran is considered high. © 2020, © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
A pre-exposure to RF-EMF can enhance the immune responses of mice following Salmonella Typhimurium and Klebsiella pneumoniae infections
Background: The queston of whether low levels of non-ionizing radiatons such as the radiofrequency electromagnetc fields (RF-EMF) can induce the same positve immune responses remains unanswered. This study aimed to investgate the effects of non-ionizing RF-EMF on some parameters of the immune system in an animal model following infecton with Salmonella Typhimurium and Klebsiella pneumoniae. Materials and Methods: Male BALB/c mice were exposed to RF-EMFs generated by a common GSM mobile phone for 3 days. Animals were infected with K. pneumonia or S. Typhimurium on the 4thday. On the7thday after injecton, blood samples were collected by cardiac puncture. The specific antbodies against bacteria were determined by agglutnaton method and serum levels of the cytokines were measured using the ELISA method. Moreover, the leukocytes count was measured using a cell counter. Results: The levels of specific antbodies against bacteria were higher in non-irradiated mice compared to irradiated mice. There were no significant differences between the irradiated and non-irradiated mice regarding the total blood leukocyte count. The mean serum levels of IFN-γ and IL-17 after infecton with K. pneumoniae were significantly higher in the irradiated mice (p<0.001). Conclusions: Low levels of RF-EMF can stmulate the immune responses in the mice pre-exposed to RF-EMF. This study provides further evidence supportng that exposure to certain levels of RF-EMF can stmulate the immune system. These adaptve responses may be applied to cope with the increased susceptbility of the astronauts to infectons during a deep space mission
Abandoned Covid-19 personal protective equipment along the Bushehr shores, the Persian Gulf: An emerging source of secondary microplastics in coastlines
During the Covid-19 pandemic, personal protection equipment (PPE) was widely used to control the virus further spared. In this study, the presence of PPE wastes along the coastline of Bushehr port, the Persian Gulf from nine stations was investigated (4 times during 40 days), and their potential for microplastics (MPs) creation was preliminarily assessed. In total, more than 2380 PPE were collected in the study area. No significant differences were found between various beaches regarding their types and common activities. In addition, the estimated disposal rate of PPE per day and year is 350 and 127,750 items, respectively. More than 10% of the collected PPE from Bushehr's coastal areas on each sampling day were damaged. Based on the microscopic analysis, the left surgical masks and torn plastic gloves in the coastal regions are emerging sources of secondary microfibers and MP particles (mostly fragments and films) in the marine environments, respectively
Toxic heavy metals and nutrient concentration in the milk of goat herds in two Iranian industrial and non-industrial zones
This work aimed to explore the concentration of nickel, manganese, iron, copper, chromium, and lead in the milk of goat herds in the industrial area of Asaluyeh (southern Iran) and the non-industrial area of Kaki. The milk of 16 goat herds (each herd had at least ten goats) was collected in several villages in each area, and at the same time, the drinking water and forage of goats were sampled. The concentration of elements in the samples was determined by ICP-OES. The mean concentrations of chromium, copper, iron, manganese, lead, and nickel in milk samples of the Asaluyeh area were 16.423 ± 0.349, 0.146 ± 0.118, 6.111 ± 0.501, 0.239 ± 0.016, 0.141 ± 0.030, and 1.447 ± 0.101 mg/kg, respectively. Concentrations of heavy metals (except for copper) in the milk of goats in the industrialized area of Asaluyeh were significantly higher than that of Kaki (P < 0.05). Also, the content of heavy metals was significantly correlated with lactose levels (P < 0.05). The hazard index for drinking the goat milk was computed to be 0.444 and 0.386 for the Asaluyeh and Kaki area, respectively, which shows a minimal effect of this exposure pathway
Multi-walled carbon nanotubes modified with iron oxide and silver nanoparticles (MWCNT-Fe 3 O 4 /Ag) as a novel adsorbent for determining PAEs in carbonated soft drinks using magnetic SPE-GC/MS method
The synthesis of compounds with an excellent adsorption capability plays an essential role to remove contaminants such as phthalic acid esters (PAEs) with potential carcinogenic characteristics from different food products. In this context, for the first time, a novel adsorbent (MWCNT-Fe 3 O 4 /Ag) was synthesized by using iron (magnetic agent), and silver (catalytic and surface enhancer agent) to further approach in a magnetic SPE-GC/MS method for determining of PAEs in carbonated soft drink samples. The limit of detection (LOD) and limit of quantification (LOQ) values of MSPE-GC/MS were determined in six PAEs as a range of 10.8�22.5 and 36�75 ng/L, respectively. Also, the calibration curves of PAEs were linear (R 2 = 0.9981�0.9995) over the concentration level of 10.000 ng/L and the recoveries of the six PAEs were ranging from 96.60 to 109.22 with the RSDs less than 8. Moreover, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray diffraction (XRD), vibrating sample magnetometry (VSM) and transmission electron microscopy analyses (TEM) were utilized to characterize the produced MWCNT-Fe 3 O 4 /Ag. Based on the findings, the surface of MWCNT is relatively uniform, which became coarser after loading with Fe 3 O 4 /Ag particles. Also, EDX spectrum showed the carbon (C), iron (Fe), oxygen (O), Ag and copper (Cu) are the main components of synthesized MWCNTs-Fe 3 O 4 /Ag. The successful adhesion of Fe 3 O 4 /Ag on the texture of MWCNTs using a co-precipitation method was confirmed by XRD and FT-IR assays. Additionally, excellent crystallinity and clear lattice nanocrystals fringes of prepared MWCNT-Fe 3 O 4 /Ag was demonstrated by TEM analysis. Based on the obtained VSM images, the prepared sorbent (MWCNT-Fe 3 O 4 /Ag) has the good magnetic performance for magnetic separation and extraction processes. It was concluded that the synthesized MWCNT-Fe 3 O 4 /Ag could be used as an efficient adsorbent for determining contaminants such as PAEs in different beverage samples. © 2018 The Author
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