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1.
ACS ES T Water ; 4(2): 492-499, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38356927

RESUMO

Plastic microbeads were widely used as exfoliants in personal care products (PCPs; e.g., hand/body washes) in North America, but restrictions were imposed on their use in PCPs in the U.S. (2017) and Canada (2018). We provide the first assessment of whether restrictions are effectively reducing microbeads entering surface waters. We examined their abundance, character, and trends in wastewater treatment plant (WWTP) effluents in Toronto, Canada, from 2016 to 2019, and in adjacent Lake Ontario surface waters (2015 and 2018), encompassing the period before and after the bans. Microbeads isolated from PCPs purchased in 2015 provided a visual morphological key with "irregular" and "spherical" microbead categories. Median concentrations of irregular microbeads, composed of polyethylene plastic, declined by up to 86% in WWTP effluents from 8.4 to 14.3 particles/m3 before to 2.0-2.2 particles/m3 after the bans, while those of spherical microbeads, predominantly synthetic/polyethylene wax, ranged within 0.5-2.3 particles/m3 and did not differ before and after the bans since, as nonplastic, they were not regulated. Similarly, amounts of irregular microbeads declined relative to spherical microbeads in Lake Ontario, indicating that product changes may be influencing observations in lake waters. The results suggest that the Canadian and U.S. restrictions effectively and rapidly reduced plastic microbeads entering waters via WWTPs.

2.
Environ Sci Pollut Res Int ; 30(59): 124182-124194, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37996593

RESUMO

Potential exposure to 14 per- and polyfluoroalkyl substances (PFAS) through seafood consumption was investigated in widely consumed seafood (Platycephalus indicus, Lethrinus nebulosus, and Penaeus semisulcatus) from the Persian Gulf. A total of 61 samples of fish and prawns were purchased from local fishers at Bushehr port (Persian Gulf, South-West of Iran) and were analyzed for PFAS compounds. In addition, potential factors influencing factor of PFAS bioaccumulation in fish and invertebrates such as age, sex, and habitat, were investigated. Æ©PFAS concentrations were in the range of 2.3- 6.1 ng/g-d.w (mean = 3.9 ± 1.9) in studied species which are equal to 0.46-1.2 ng/g-w.w according to their conversion factor. Perfluorooctane sulfonic acid (PFOS) was the most abundant perfluorinated compound in studied organisms and tissues. The results of correlation analysis showed that the bioaccumulation of PFAS in aquatic organisms is significantly correlated to the length of the compound's carbon chain, the identity of anionic group, and organism's age, sex, and habitant. The risk assessment using hazard index calculation and Monte-Carlo simulation indicated that weekly consumption of prawn and fish fillets does not pose a health risk to adults but might threaten children's health. However, the risk posed by PFAS exposure via entire fish or fish liver intake is an important issue for wild marine mammals (i.e., dolphins). So, accurate and routine monitoring of PFAS in aquatic environments seems mandatory to preserve wildlife and human health in the Persian Gulf.


Assuntos
Ácidos Alcanossulfônicos , Decápodes , Fluorocarbonos , Poluentes Químicos da Água , Animais , Adulto , Criança , Humanos , Oceano Índico , Ácidos Alcanossulfônicos/análise , Alimentos Marinhos/análise , Peixes , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Mamíferos
3.
Environ Res ; 215(Pt 2): 114337, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36116495

RESUMO

Marine pollution with personal protective equipment (PPE) has recently gained major attention. Multiple studies reported the release of microplastics (MPs) and chemical contaminants from face masks, the most used PPE type. However, not much is known concerning the release of phthalate esters (PAEs) in aquatic media, as well as the hazard posed by other types of PPE. In the present study, we investigated the release of MPs and PAEs from face masks and gloves recovered from the environment. The results indicated that both PPEs release MPs comparable to the literature, but higher concentrations were presented by face masks. In turn, the total concentration of six PAEs was higher in gloves than in face masks. The release of these contaminants is exacerbated over time. The present study allows researchers to understand the contribution of PPE to marine pollution while accounting for gloves, a generally overlooked source of contaminants.


Assuntos
COVID-19 , Ácidos Ftálicos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Ésteres , Humanos , Máscaras , Microplásticos , Pandemias , Plásticos
4.
Mar Pollut Bull ; 178: 113587, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35397345

RESUMO

Investigations of the physicochemical degradation of personal protective equipment (PPE) under controlled environmental conditions are largely lacking. Here the chemical and physical changes of face masks and gloves (recovered from the marine environment) were evaluated after exposure time up to 60 days of simulated environmental conditions. The results suggested that the polymer backbone of PPE suffers typical changes induced by sun exposure. Changes in the intensity of diffraction peaks indicated shifts in the crystallinity of PPE, possibly altering their thermal behavior. Signs of physical degradation in PPE, such as ruptures, and rough surfaces, which exacerbated over time were also detected. Additionally, signals of some elements of concern, such as Cu and Mo, and elements typically found in seawater were detected. The results of this study allowed us to better understand the degradation of typical PPE items in the marine environment, ultimately resulting in the release of microplastics and chemical contaminants.


Assuntos
Equipamento de Proteção Individual , Plásticos
5.
Environ Res ; 202: 111706, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34284015

RESUMO

Trillions of cigarette butts (CBs) are released into the environment and the leached potentially toxic elements (PTEs) from CBs may contaminate the environments. In this study, the leaching of PTEs including both heavy metals and metalloids (metal(loid)s) from CBs into deionized water (DW), tap water (TW), and seawater (SW) was checked during the different contact times (from 60 min to 60 days). According to the results, PTEs were leached from CBs into different water samples. However, there were no significant differences between leachates in DW and TW samples (p > 0.05). The results of the distribution coefficient indicated the high tendency of most PTEs to enter the liquid phase. The levels of leached PTEs into DW and TW exceeded the standards of surface freshwater to maintain aquatic life. Although the maximum level of leached metal(loid)s into DW, TW, and SW occurred at different times, for each type of water sample no significant differences were found among the levels of most PTEs at various contact times. Based on the results, the levels of leached metal(loid)s from CBs in seawater peak soon after being released into the water, while for the freshwater, they occur after some days. This phenomenon could possibly have short-term and long-term effects on marine and freshwater organisms, respectively. Due to the ability of the dissolved PTEs to integrate into the aquatic/terrestrial food web and threaten human health, some control measures regarding the disposal of CBs are necessary.


Assuntos
Metais Pesados , Produtos do Tabaco , Ecossistema , Monitoramento Ambiental , Água Doce , Humanos , Metais Pesados/análise , Água
6.
Mar Pollut Bull ; 168: 112386, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33901902

RESUMO

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.


Assuntos
COVID-19 , Equipamento de Proteção Individual , Humanos , Oceano Índico , Microplásticos , Pandemias , Plásticos , SARS-CoV-2
7.
Mar Pollut Bull ; 166: 112241, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33711611

RESUMO

The occurrence of endocrine disrupting chemicals (EDCs) has been determined in two widely consumed fish species from Persian Gulf i.e., Epinephelus coioides and Platycephalus indicus by applying a validated analytical for the simultaneous detection of fourteen EDCs. The concentrations of all detected EDCs were greater in the liver than in the muscle (except for bisphenol A in P. indicus), suggesting a prolonged exposure of the fishes to these pollutants in the Persian Gulf. Specifically, the results showed that di (2-ethylhexyl) phthalate (DEHP) was the compound detected most frequently and at the highest concentration in both species. DEHP levels in ranged from 6.68 to 297.48 µg g-dw-1 and from 13.32 to 350.52 µg g-dw-1, in muscle and in liver, respectively. A risk assessment study was conducted, and demonstrated that consuming two fish based- meals per week may result in a moderate risk especially for vulnerable population groups.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Animais , Disruptores Endócrinos/análise , Monitoramento Ambiental , Humanos , Oceano Índico , Medição de Risco , Poluentes Químicos da Água/análise
8.
Environ Res ; 195: 110881, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33607099

RESUMO

Cigarette butts (CBs) are the most frequently littered pieces of environmental wastes which are released both directly and indirectly into the environment and finally may reach aquatic environments and contaminate aquatic biomes. However, to date, there is no comprehensive review on the extent and magnitude of the potential effects of CBs on aquatic organisms. Hence, a systematic review of published studies was conducted in this paper to survey the fate of CBs in the aquatic environments and also the impacts of exposure to CBs on survival, growth, and reproduction of aquatic organisms. The gathered data showed that the leachates of CBs in the aquatic environment could extremely be toxic for various organisms and increasing the exposure time, increases the mortality rate. In addition, smoked filtered CBs with tobacco remnants have higher mortality rate compared to unsmoked filtered butts (USFs) for Hymenochirus curtipes, Clarias gariepinus, tidepool snails, Atherinops affinis and Pimephales promelas. The fate of CBs in the aquatic environments is affected by various factors, and prior to sinking they are floated for a long time (long distance). Hence, CBs and their associated toxic chemicals might be ingested by diverse aquatic organisms. However, further studies are necessary to understand the exact toxicity of CBs on different freshwater and marine organisms and also their fate in the aquatic media. The results of this review showed the essentiality of regulations to prevent the release of chemical and toxic compounds into the aquatic environments.


Assuntos
Produtos do Tabaco , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Água Doce , Fumaça/análise , Poluentes Químicos da Água/toxicidade
9.
Environ Pollut ; 276: 116668, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33611204

RESUMO

The presence of polycyclic aromatic hydrocarbons (PAHs) in the fetal environment is a high-priority concern due to the fetus being more sensitive than adults to these ubiquitous xenobiotics. The aim of the present study was to compare the maternal and fetal serum levels of ΣPAHs and their effects on fetal growth in an industrial and an urban area in Southwest Iran. The industrial area was the petrochemical and gas area (PGA) of the Central District of Asaluyeh County and the urban area (UA) was the Central District of Bushehr County, Ninety-nine maternal serum (MS) and 99 cord serum (CS) samples from the PGA and 100 MS and 100 CS samples from the UA were collected during May 2018 to February 2019. The mean concentrations of ΣPAHs were significantly (p < 0.05) higher in the PGA than the UA in both MS (157.71 vs. 93.56 µg/L) and CS (155.28 vs. 93.19 µg/L) samples. Naphthalene (NAP) was the predominant PAH detected in all the studied samples. Significant negative associations were found between birth weight and anthracene (ANT) level in MS (ß = -22.917, p = 0.032; weight decrement = 22.917 g for a 1 µg/L increase in ANT); head circumference and chrysene (CHR) level in MS (ß = -0.206, p = 0.023; head circumference decrement = 0.206 cm for a 1 µg/L increase in CHR); and birth height and NAP level in CS (ß = -0.20, p = 0.005; height decrement = 0.20 cm for a 1 µg/L increase in NAP). Maternal diet had a significant effect on the serum levels of PAHs. The results of this study showed that transmission of PAHs from mother to fetus through the cord blood is an important issue and mothers who live in industrial areas and consume PAH-containing foodstuffs, and their fetuses, are more at risk than those living in a non-industrial urban area.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Adulto , China , Dieta , Monitoramento Ambiental , Feminino , Desenvolvimento Fetal , Humanos , Irã (Geográfico) , Mães , Hidrocarbonetos Policíclicos Aromáticos/análise , Gravidez
10.
Environ Res ; 192: 110339, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33068583

RESUMO

Exposure to fine particulate matter (PM2.5) and their associated microcontaminants have been linked to increased harmful effects on the human health. In this study, the possible relationships between PM2.5, microplastics (MPs), and polycyclic aromatic hydrocarbons (PAHs) were analyzed in an urban area of Bushehr port, in the northern part of the Persian Gulf. Presence, sources, and health risks of MPs and PAHs in both normal and dusty days were also investigated. The median of PM2.5 and Æ©PAHs were 52.8 µg/m3 and 14.1 ng/m3, respectively, indicating high pollution levels especially in dusty days. The mean level of MPs in urban suspended PM2.5 was 5.2 items/m3. Fragments were the most abundant shape of identified MPs and polyethylene terephthalate (PET) was the most plastic types in urban dust of Bushehr port. The results revealed that PM2.5 and MPs may possibly act as a carrier for airborne MPs and PAHs, respectively. In addition, the significant positive relationships between MPs, wind speed and wind direction, confirmed that the MPs transportation were highly controlled by atmospheric condition. Moreover, the source identification methods and trajectory analyses indicated that petrogenic sources from both proximal and distal origins play an important role in the level of PAHs. The results of chronic health risk evaluation via inhalation revealed that PM2.5-bound PAHs had high potential cancer risk in winter, while, the estimated risks for non-carcinogenic PAHs were not considerable. In the case of MPs, the assessment of human intake of MPs via inhalation highlighted the possible risks for habitants.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , China , Monitoramento Ambiental , Humanos , Microplásticos , Material Particulado/análise , Material Particulado/toxicidade , Plásticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Estações do Ano
11.
Mar Pollut Bull ; 160: 111633, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181921

RESUMO

The existence of microplastics (MPs) in canned fish (tuna and mackerel) samples was investigated and their composition, possible sources and potential intake were assessed. Light and fluorescence microscopy were used for the quantification of potential MPs. Furthermore, micro-Raman microscopy, and scanning electron microscopy coupled with an energy dispersive X-ray were used to identify the polymer types and composition of MPs. The results showed that 80% of samples had at least one plastic particle and fibers were the most abundant shapes of MPs. Moreover, polyethylene terephthalate (32.8%) was the most common polymer type in canned fish samples. The fish, food additives, and contact materials during the cleaning and canning process are possible sources of MPs. Human intake estimation of MPs showed the possibility of plastics absorption by humans who consume canned fish several times/week. Hence, the results of this study showed the importance of MPs' guidelines for food safety and hygiene.


Assuntos
Plásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Peixes , Humanos , Microplásticos , Alimentos Marinhos , Atum , Poluentes Químicos da Água/análise
12.
J Hazard Mater ; 392: 122271, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32311916

RESUMO

Contaminants of emerging concern (CECs) have recently been detected in bottled water and have brought about discussions on possible risks for human health. However, a systematic review of CECs in bottled water is currently lacking due to the relatively new introduction and/or detection of these pollutants. Hence, this paper reviews the existing studies on the presence of six major groups of emerging contaminants including microplastics (MPs), pharmaceuticals and personal care products (PPCPs), bisphenol A (BPA), phthalates, alkylphenols (APs), and perfluoroalkyl and polyfluoroalkyl substances (PFASs) in bottled water from different countries. Also, the findings related to CECs' levels, their possible sources, and their risks are summarized. The gathered data indicate that MPs within the size range of 1-5 µm are the most predominant and potentially toxic classes of MPs in bottled water. In addition, PPCPs, PFASs, APs, and BPA occur in concentration levels of ng/L, while phthalates occur in the µg/L level in bottled water. The bottle type plays an important role in the contamination level. As expected, water in plastic bottles with plastic caps is more polluted than in glass bottles. However, other sources of contamination such as contact materials during cleaning, bottling, and storage are not negligible. Based on the gathered data in this review, the CEC levels except for MPs (no threshold values) in bottled water of most countries do not raise a safety concern for the human. However, the occurrence of individual CECs and their association in bottled water need more accurate data to understand their own/synergistic effects on human health.


Assuntos
Água Potável/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental
13.
Mar Pollut Bull ; 154: 111036, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32174489

RESUMO

The presence of chemicals in marine organisms is an important issue for human health due to the growing rate of seafood consumption. Potential exposure to seven bisphenol analogues through seafood consumption was investigated in some popular seafood from the Persian Gulf. Bisphenols were analyzed by gas chromatography-mass spectrometry. Bisphenol A (BPA) and bisphenol B (BPB) were the first and second most common bisphenols in the studied samples, respectively. The highest levels of BPA (mean 13.58 ± 5.70 µg/kg.dw) and BPB (mean 10.30 ± 7.98 µg/kg.dw) were found in E.coioides species. Bisphenol F and bisphenol AF were detected only in P. armatus and L. klunzingeri, respectively. Trophic transfer investigation demonstrated that BPA and BPB were biomagnified in the studied organisms through their diet. The eco-toxicity and estrogenic risk assessment indicated that seafood consumption does not pose a health threat to consumers. However, routine monitoring of bisphenols in seafood seems to be necessary to ensure food safety.


Assuntos
Compostos Benzidrílicos , Exposição Ambiental/estatística & dados numéricos , Alimentos Marinhos/estatística & dados numéricos , Poluição da Água/estatística & dados numéricos , Dieta , Humanos , Oceano Índico , Estado Nutricional , Fenóis , Medição de Risco
14.
Artigo em Inglês | MEDLINE | ID: mdl-31393815

RESUMO

High bioavailability of microplastics (MPs) in the marine environment has raised serious concern during the last few decades. Nevertheless, the trophic transfer of MPs within edible parts of the marine food webs remain unknown. In this study, bioaccumulation, biomagnification, and potential human intake of MPs in muscles and gills of five popular commercial species (3 fish, 1 crab, and 1 prawn) from the Persian Gulf were investigated. The surface structure characteristics of the material and elemental composition signatures were used to screen for likely MPs and rule out non-plastics. Among the studied species, Penaeus semisulcatus and Epinephelus coioides displayed the highest (mean 0.360 items/g muscle) and lowest (mean 0.158 items/g muscle) MPs level in their muscles, respectively. The number of extracted MPs from the gills was higher than the muscle of the analyzed species, especially when it comes to scavengers and filter feeders such as (Liza klunzingeri, Portunus armatus, and P. semisulcatus).The results of the trophic magnification factor (TMF) and biomagnification factor (BMF) calculation indicated that MPs were not biomagnified in edible parts of the marine food web of the Persian Gulf. Hence, contrary to previous belief, MPs trophic dilution occurs rather than magnification in edible parts of seafood. The assessment of human intake of MPs highlights the possible risks posed by seafood consumption to the the human population depending to a great extent on a seafood diet. Considering possible physical and chemical toxicity of MPs and their associated contaminants, routine consumption of high doses of the studied seafood should be controlled for vulnerable groups such as pregnant/lactating women and their children to ensure their safety.


Assuntos
Monitoramento Ambiental , Contaminação de Alimentos/análise , Plásticos/efeitos adversos , Plásticos/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/efeitos adversos , Poluentes Químicos da Água/análise , Animais , Sedimentos Geológicos , Brânquias , Humanos , Irã (Geográfico) , Músculos , Plásticos/metabolismo , Controle de Qualidade
15.
Environ Geochem Health ; 41(6): 2803-2820, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31177477

RESUMO

High bioavailability of man-made pollutants in marine environments raises serious concern regarding the safety of seafood. In the present study, the presence, trophic transfer, and risks of polycyclic aromatic hydrocarbons (PAHs), and potentially toxic elements (PTEs) in 170 benthic marine organisms (87 prawn; 28 crab; 55 fish) from the Persian Gulf were investigated. Among investigated species, E. coioides displayed the lowest level of metal pollution index (MPI), while P. armatus and P. semisulcatus showed the highest level of MPI and total PAHs, respectively. Principal component biplot exhibited a significant association of PTEs (except Hg) and PAHs in less motile benthic species. The results of trophic transfer investigation revealed that PTEs (except Hg) and PAHs were not biomagnified in the studied organisms through diet. However, Hg biomagnification factors greater than 1 indicated trophic transfer of mercury. In order to gain nutritional benefits of seafood, consumption of two fish/prawn meals/week for adults (except vulnerable groups such as pregnant women) and one fish/prawn meals/week for children is recommended. However, lifelong consumption of crabs (P. armatus) may threaten human health. In addition, the maximum allowable fish consumption rate (CRlim) for studied fish is 120 g fish/day for adults and 30 g fish/day for children. In the case of prawns, the safe dose is 30 and 10 g prawns/day for adults and children, respectively.


Assuntos
Exposição Dietética/efeitos adversos , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Adulto , Animais , Criança , Exposição Dietética/análise , Exposição Dietética/prevenção & controle , Feminino , Peixes , Humanos , Oceano Índico , Mercúrio/análise , Metais/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Gravidez , Medição de Risco , Frutos do Mar/análise , Poluentes Químicos da Água/toxicidade
16.
J Environ Health Sci Eng ; 17(2): 657-669, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32030141

RESUMO

Soil contamination with heavy metals due to the application of fertilizers and biocides in agricultural activities is a potential threat for human health through the food chain. The present work was designed to study the spatial distribution of heavy metals, pollution level and possible reasons for their contamination in agricultural soils of Aghili plain, Khuzestan, Iran. The median concentrations of As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, V, Zn, and Hg were 2.90, 0.29, 8.10, 39.0, 17.75, 354.0, 0.97, 58.35, 5.90, 34.0, 42.0, and 0.01 mg/kg, respectively. The results revealed that average concentrations of all studied heavy metals with an exception of Co, Cu, and Ni, were lower than background values. Analysis of source identification showed that Zn, Pb, and Cu (P < 0.01, r > 0.9) and Co, Cr, Mn, Ni, and V (P < 0.01, r > 0.7) were mainly from anthropogenic. In addition, Cd probably was originated from agricultural activities (application of manure and phosphorous fertilizers). Enrichment factor values of all metals (except Ni), were in the range of non to moderate enrichment (EF < 5). According to the degree of contamination (Cd) and ecological risk factor (ERF), all stations were categorized as low to moderate contaminated sites (4.5 < Cd < 17), and biological communities in some locations may be at risk (ERF >65). Results indicate that application of fertilizers, herbicides and pesticides in agricultural soils has led to soil contamination and special management and educational plans are needed for public and farmers to prevent further adverse effects.

17.
Environ Sci Pollut Res Int ; 25(31): 31407-31420, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30196464

RESUMO

Oil- and gas-produced water (PW) which contains various pollutants is an enormous threat to the environment. In this study, a novel low-cost bio-adsorbent was prepared from shrimp shell and acid-activated montmorillonite. The results of FT-IR spectroscopy, energy dispersive X-ray (EDX) analysis, and SEM-EDX technique indicated that the chitosan-activated montmorillonite (CTS-A-MMT) was prepared successfully. The synthesized CTS-A-MMT was applied to remove simultaneously five cationic and anionic metal species and crude oil from synthetic and real oilfield PW. The adsorption data indicated that crude oil and all studied metals (except As) were adsorbed to CTS-A-MMT in a monolayer model (best fitted by Langmuir model), while As adsorption fits well with Freundlich model. Kinetic models' evaluation demonstrated that the adsorption kinetics of metals on CTS-A-MMT are initially controlled by the chemical reaction (film diffusion) followed by intra-particle diffusion. Application of the prepared CTS-A-MMT in real oilfield PW indicated removal efficiency of 65 to 93% for metals and 87% for crude oil in simultaneous removal experiments. Presence of additional ions in PW decreased the removal of studied metals and crude oil considerably; however, the concentration of the investigated pollutants in treated PW is less than the ocean discharge criteria. It is concluded that the prepared CTS-A-MMT composite is a low-cost and effective adsorbent for treating wastewater contaminated with crude oil and heavy metals (i.e., PW).


Assuntos
Bentonita/química , Metais Pesados/isolamento & purificação , Campos de Petróleo e Gás , Petróleo , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Quitosana/química , Cinética , Metais Pesados/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
18.
Environ Pollut ; 232: 154-163, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28943346

RESUMO

Although weekly consumption of fish is recommended, the presence of contaminants in seafood has raised many concerns regarding the benefits of fish intake. In the present study microplastics (MPs) and metals' concentration in muscles of both benthic and pelagic fish species from northeast of Persian Gulf were investigated and the risk/benefit of their consumption was assessed. The results demonstrated that MPs and Hg in all species and Se in benthic species increase with size, while relationship between other metals, and fish size is not consistent. Consumption of a meal ration of 300 and < 100 g/week for adults and children, respectively, is recommended since it would provide the required essential elements with no human health risk. On the other hand, the estimated intake of MPs from fish muscles revealed that the mean intake of MPs for P. indicus, E. coioides, A. djedaba, and S. jello consumption is 555, 240, 233, and 169 items/300 g-week, respectively. Moreover, the relationship between MPs and metals in fish muscles were positive for A. djedaba, and negative for E. coioides. Considering the chemical toxicity of MPs and metals, and their good linear relationships in some species, consumption of high doses of the studied fish may pose a health threat to the consumers.


Assuntos
Exposição Ambiental/análise , Plásticos/análise , Poluentes Químicos da Água/análise , Adulto , Animais , Criança , Exposição Ambiental/estatística & dados numéricos , Peixes , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Oceano Índico , Mercúrio/análise , Metais , Músculos/química , Medição de Risco , Alimentos Marinhos/análise , Alimentos Marinhos/estatística & dados numéricos , Poluição Química da Água/estatística & dados numéricos
19.
Data Brief ; 14: 20-27, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28761913

RESUMO

Soil is an important component of life cycle affecting agriculture and food crops. Quality of soil resources is defined according to their potential impact on human health by exposure of harmful constituents through the food chain. Heavy metals especially As, Pb and Cd are among the most hazardous elements which could be released to the top soil through different wastewaters, fertilizers, herbicides and etc. In this research Aghili plain in Khuzestan province, Iran was selected as a total of 54 samples were prepared based on a systematic gridding procedure. Selected heavy metals concentrations were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and then zoning was performed using kriging method. Pollution level was assessed through single factor indices and pollution load index. A separate map dealing with each heavy metal was prepared to present the distribution of heavy metal in Aghili plain. In all samples the heavy metals concentrations were followed the bellow trend: Pb>As>Cd. Furthermore, based on the PLI, all stations were categorized as moderately to highly polluted sites (1

20.
Environ Sci Pollut Res Int ; 24(25): 20360-20371, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28707239

RESUMO

Environmental pollutants such as microplastics have become a major concern over the last few decades. We investigated the presence, characteristics, and potential health risks of microplastic dust ingestion. The plastic load of 88 to 605 microplastics per 30 g dry dust with a dominance of black and yellow granule microplastics ranging in size from 250 to 500 µm was determined in 10 street dust samples using a binocular microscope. Fluorescence microscopy was found to be ineffective for detecting and counting plastic debris. Scanning electron microscopy, however, was useful for accurate detection of microplastic particles of different sizes, colors, and shapes (e.g., fiber, spherule, hexagonal, irregular polyhedron). Trace amounts of Al, Na, Ca, Mg, and Si, detected using energy dispersive X-ray spectroscopy, revealed additives of plastic polymers or adsorbed debris on microplastic surfaces. As a first step to estimate the adverse health effects of microplastics in street dust, the frequency of microplastic ingestion per day/year via ingestion of street dust was calculated. Considering exposure during outdoor activities and workspaces with high abundant microplastics as acute exposure, a mean of 3223 and 1063 microplastic particles per year is ingested by children and adults, respectively. Consequently, street dust is a potentially important source of microplastic contamination in the urban environment and control measures are required.


Assuntos
Poeira/análise , Monitoramento Ambiental , Material Particulado/análise , Plásticos/análise , Adulto , Criança , Cidades , Poeira/prevenção & controle , Humanos , Irã (Geográfico) , Tamanho da Partícula , Material Particulado/química , Plásticos/química
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