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1.
Environ Res ; 251(Pt 2): 118645, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38485077

RESUMEN

Every year, a significant amount of antimony (Sb) enters the environment from natural and anthropogenic sources like mining, smelting, industrial operations, ore processing, vehicle emissions, shooting activities, and coal power plants. Humans, plants, animals, and aquatic life are heavily exposed to hazardous Sb or antimonide by either direct consumption or indirect exposure to Sb in the environment. This review summarizes the current knowledge about Sb global occurrence, its fate, distribution, speciation, associated health hazards, and advanced biochar composites studies used for the remediation of soil contaminated with Sb to lessen Sb bioavailability and toxicity in soil. Anionic metal(loid) like Sb in the soil is significantly immobilized by pristine biochar and its composites, reducing their bioavailability. However, a comprehensive review of the impacts of biochar-based composites on soil Sb remediation is needed. Therefore, the current review focuses on (1) the fundamental aspects of Sb global occurrence, global soil Sb contamination, its transformation in soil, and associated health hazards, (2) the role of different biochar-based composites in the immobilization of Sb from soil to increase biochar applicability toward Sb decontamination. The review aids in developing advanced, efficient, and effective engineered biochar composites for Sb remediation by evaluating novel materials and techniques and through sustainable management of Sb-contaminated soil, ultimately reducing its environmental and health risks.

2.
Environ Pollut ; 339: 122644, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37827352

RESUMEN

Anthropogenic-driven selenium (Se) contamination of natural waters has emerged as severe health and environmental concern. Lowering Se levels to safe limits of 40 µg-L-1 (recommended by WHO) presents a critical challenge for the scientific community, necessitating reliable and effective methods for Se removal. The primary obectives of this review are to evaluate the efficiency of different biosorbents in removing Se, understand the mechanism of adsorption, and identify the factors influencing the biosorption process. A comprehensive literature review is conducted to analyze various studies that have explored the use of modified biochars, iron oxides, and other non-conventional biosorbents for selenium removal. The assessed biosorbents include biomass, microalgae-based, alginate compounds, peats, chitosan, and biochar/modified biochar-based adsorbents. Quantitative data from the selected studies analyzed Se adsorption capacities of biosorbents, were collected considering pH, temperature, and environmental conditions, while highlighting advantages and limitations. The role of iron impregnation in enhancing the biosorption efficiency is investigated, and the mechanisms of Se adsorption on these biosorbents at different pH levels are discussed. A critical literature assessment reveals a robust understanding of the current state of Se biosorption and the effectiveness of non-conventional biosorbents for Se removal, providing crucial information for further research and practical applications in water treatment processes. By understanding the strengths and limitations of various biosorbents, this review is expected to scale-up targeted research on Se removal, promoting the development of innovative and cost-effective adsorbents, efficient and sustainable approaches for Se removal from water.


Asunto(s)
Selenio , Contaminantes Químicos del Agua , Purificación del Agua , Hierro , Carbón Orgánico/química , Temperatura , Adsorción , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Cinética
3.
J Environ Sci (China) ; 133: 152-160, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37451784

RESUMEN

Solid fuel use (SFU) is common in most developing countries and would release many hazardous air pollutants posing high risks on human health. The Global Burden of Disease (GBD) study highlighted risks associated with household SFU in Pakistan, however, high uncertainties prevail because of scanty data on SFU and unaccounted energy stacking. This study conducted a field campaign aiming at collecting first-hand data on household energy mix in Pakistan. The first survey was in Punjab and Azad Kashmir, and revealed that stacked energy use was pervasive, especially for cooking. The stacking was found to be much more obvious in SFU households (defined as those using SFU dominantly) compared to those non-SFU. There were significantly substantial differences between Azad Kashmir and Punjab because of distinct resources available and economic conditions. Woody materials comprised up to nearly 70% in Azad Kashmir, but in Punjab, gas was frequently used for cooking. Only investigating primary household energy would probably overestimate main energy types that being used for a longer time but underestimated other supplements, suggesting the preference of multiple-energy surveys in household energy studies.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Humanos , Pakistán , Composición Familiar , Contaminantes Atmosféricos/análisis , Encuestas y Cuestionarios , Culinaria , Contaminación del Aire Interior/análisis
4.
Environ Geochem Health ; 45(3): 585-606, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35347514

RESUMEN

In order to expound on the present situation and potential risk of road dust heavy metals in major cities, a total of 114 literatures mainly over the past two decades, involving more than 5000 sampling sites in 61 cities of 21 countries, were screened through the collection and analysis of research papers. The concentration, sources, distribution, health risk, sample collection, and analytical methods of heavy metal research on road dust in cities around the world are summarized. The results show that Cd, Zn, and Cu in many urban road dusts in the world are higher than the grade II of the Chinese maximum allowable concentration of potentially toxic elements in the soil. Geo-accumulation index values show that Pb > Cd > Zn > Cu had the highest contamination levels. Hazard index assessment indicates Pb and Cr had the highest potential health risk, especially for children in which ingestion was found as the main exposure pathway. Moreover, through comparative analysis, it is found that some pollutants are higher in developed and industrialized cities and transport (53%) followed by industrial emissions (35%) provide the major contributions to the sources of heavy metals.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Niño , Humanos , Monitoreo del Ambiente/métodos , Polvo/análisis , Ciudades , Cadmio/análisis , Plomo/análisis , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Medición de Riesgo/métodos , China
5.
Environ Geochem Health ; 45(3): 1013-1026, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35635682

RESUMEN

The current study features PAHs exposure on Karakoram Highway, a route of utmost importance in Pakistan. The drivers of heavy traffic vehicles (HTV) on Karakoram Highway spend long hours amid dense traffic and therefore, inevitably inhale huge amount of PAH carcinogens. The urinary metabolites of PAHs in such drivers (meeting selection criteria n = 48) and a control group (n = 49) were comparatively profiled. The higher urinary biomarkers among ninety-six percent HTV drivers were evident of PAHs exposure. We observed elevated concentrations of urinary benzo[a]pyrene metabolites (3-OH-BaP = 3.53 ± 0.62 ng g-1 creatinine and 9-OH-BaP = 3.69 ± 0.74 ng g-1 creatinine) in HTV driver's samples compared to controls (0.85 ± 0.08 and 0.31 ± 0.03 ng g-1 creatinine, respectively). Interestingly, urinary benzo[a]pyrene metabolites were detected in almost similar amount among HTV drivers irrespective of their working hours. A distinct smoking effect was manifested with rising urinary levels of 1-hydroxypyrene, 2-hydroxyphenanthrene, and 3-hydroxybenzo[a]pyrene with corresponding increase in driving hours per day. These metabolites exhibited characteristic exposures to low molecular weight volatile PAHs that are commonly found in vehicular exhaust. The elevated PAH body burden was directly linked to the nature of their job and the route-long environmental pollution on Karakoram Highway. Additionally, the poor economic status and smoking also increased HTV driver's health vulnerability and significantly declined their health capacity. There was conclusive evidence that HTV drivers were exposed to PAHs during a ride on Karakoram Highway, back and forth, an aspect not reported earlier.


Asunto(s)
Exposición Profesional , Hidrocarburos Policíclicos Aromáticos , Benzo(a)pireno/análisis , Exposición Profesional/análisis , Creatinina , Monitoreo del Ambiente/métodos , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/orina , Pirenos/metabolismo , Biomarcadores/orina
6.
Environ Geochem Health ; 45(5): 1359-1389, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35972610

RESUMEN

Selenium (Se) is an essential metalloid and is categorized as emerging anthropogenic contaminant released to the environment. The rise of Se release into the environment has raised concern about its bioaccumulation, toxicity, and potential to cause serious damages to aquatic and terrestrial ecosystem. Therefore, it is extremely important to monitor Se level in environment on a regular basis. Understanding Se release, anthropogenic sources, and environmental behavior is critical for developing an effective Se containment strategy. The ongoing efforts of Se remediation have mostly emphasized monitoring and remediation as an independent topics of research. However, our paper has integrated both by explaining the attributes of monitoring on effective scale followed by a candid review of widespread technological options available with specific focus on Se removal from environmental media. Another novel approach demonstrated in the article is the presentation of an overwhelming evidence of limitations that various researchers are confronted with to overcome achieving effective remediation. Furthermore, we followed a holistic approach to discuss ways to remediate Se for cleaner environment especially related to introducing weak magnetic field for ZVI reactivity enhancement. We linked this phenomenal process to electrokinetics and presented convincing facts in support of Se remediation, which has led to emerge 'membrane technology', as another viable option for remediation. Hence, an interesting, innovative and future oriented review is presented, which will undoubtedly seek attention from global researchers.


Asunto(s)
Selenio , Selenio/análisis , Ecosistema , Contaminación Ambiental
7.
Environ Sci Pollut Res Int ; 29(22): 32513-32544, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35190984

RESUMEN

Erythromycin (ERY), designated as a risk-prioritized macrolide antibiotic on the 2015 European Union watch list, is the third most commonly used antibiotic, most likely due to its ability to inhibit the protein. ERY has revealed record-high aquatic concentrations threatening the entire ecosystem and hence demands priority remedial measures. The inefficiency of various conventional ERY degradation methodologies opened up a gateway to advanced technologies. The conventional approach comprising of a chemically formulated, single photocatalyst has a major drawback of creating multiple environmental stresses. In this context, photocatalysis is grabbing tremendous attention as an efficient and cost-effective antibiotic treatment approach. Several studies have ascertained that ZnO, TiO2, Fe3O4, and rGO nanoparticles possess remarkable pollution minimizing operational capabilities. Additionally, composites are found much more effective in antibiotic removal than single nanoparticles. In this review, an attempt has been made to provide a comprehensive baseline for efficient reactive radical production by a phyto-mediated composite kept under a certain source of irradiation. Considerable efforts have been directed towards the in-depth investigation of rGO-embedded, phyto-mediated ZnO/TiO2/Fe3O4 photocatalyst fabrication for efficient ERY degradation, undergoing green photocatalysis. This detailed review provides photocatalytic nanocomposite individualities along with a hypothetical ERY degradation mechanism. It is assumed that derived information presented here will provoke innovative ideas for water purification incorporating green photocatalysis, initiating the construction of high-performance biogenic hierarchical nanocatalysts.


Asunto(s)
Purificación del Agua , Óxido de Zinc , Antibacterianos , Catálisis , Ecosistema , Eritromicina
8.
PLoS One ; 17(1): e0262451, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35045121

RESUMEN

Climate change has been discussed as to exert shifts in geographical range of plants, animals or insect species by increasing, reducing or shifting its appropriate climatic habitat. Globally, Pakistan has been ranked at 5th position on the list of countries most vulnerable to climate change in 2020. Climate change has resulted in the losses of biodiversity and alteration in ecosystem as a result of depletion of natural habitats of species in Pakistan as well as in the world. Ants have been regarded as indicators of environmental change and ecosystem processes. Brachyponera nigrita (Emery, 1895) was reported for the first time from Pakistan (Pothwar region). Objective of our studies was to model geographic distribution of newly recorded ant species, B. nigrita based on two representative concentration pathways (RCP) (RCP4.5 and RCP8.5) for 2050s using maximum entropy model (Maxent) in Pakistan. In modeling procedure, 21occurrence records and 8 variables namely Bio4 (Temperature seasonality), Bio8 (Mean temperature of wettest quarter), Bio10 (Mean temperature of warmest quarter), Bio12 (Annual precipitation), Bio13 (Precipitation of wettest month), Bio15 (Precipitation seasonality), Bio17 (Precipitation of driest quarter) and Bio18 (Precipitation of warmest quarter) were used to determine the current and future distributions. Performance of the model was evaluated using AUC (area under curves) values, partial ROC, omission rates (E = 5%) and AICc (Model complexity).The results showed the average AUC value of the model was 0.930, which indicated that the accuracy of the model was excellent. The jackknife test also showed that Bio4, Bio18, Bio17 and Bio15 contributed 98% for the prediction of potential distribution of the species as compared to all other variables. Maxent results indicated that distribution area of B. nigrita under future predicted bioclimatics 2050 (RCP 4.5 and RCP8.5) would be increased in various localities of Pakistan as compared to its current distribution. In Pothwar region, moderately suitable and highly suitable areas of this species would increase by 505.932321km2and 572.118421km2as compared to current distribution under 2050 (RCP 4.5), while under 2050 (RCP 8.5), there would be an increase of 6427.2576km2and 3765.140493km2 respectively in moderately suitable and highly suitable areas of B. nigrita. This species was associated with termites, collembolans and larval stages of different insects. White eggs, creamy white pupae and many workers of this species were observed in a variety of habitats. Unknown nesting ecology, species identification characters supported with micrographs has been given which will help researchers for further ecological studies.


Asunto(s)
Hormigas/fisiología , Demografía/tendencias , Biomarcadores Ambientales/fisiología , Animales , Biodiversidad , Cambio Climático , Ecología , Ecosistema , Modelos Epidemiológicos , Geografía , Pakistán , Temperatura
9.
Innovation (Camb) ; 2(1): 100071, 2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33521765

RESUMEN

The COVID-19 outbreak has already become a global pandemic and containing this rapid worldwide transmission is of great challenge. The impacts of temperature and humidity on the COVID-19 transmission rate are still under discussion. Here, we elucidated these relationships by utilizing two unique scenarios, repeated measurement and natural experiment, using the COVID-19 cases reported from January 23 - February 21, 2020, in China. The modeling results revealed that higher temperature was most strongly associated with decreased COVID-19 transmission at a lag time of 8 days. Relative humidity (RH) appeared to have only a slight effect. These findings were verified by assessing SARS-CoV-2 infectivity under the relevant conditions of temperature (4°C-37°C) and RH (> 40%). We concluded that temperature increase made an important, but not determined, contribution to restrain the COVID-19 outbreak in China. It suggests that the emphasis of other effective controlling polices should be strictly implemented to restrain COVID-19 transmission in cold seasons.

10.
Sci Total Environ ; 772: 145389, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33578171

RESUMEN

Wide spread documentation of antibiotic pollution is becoming a threat to aquatic environment. Erythromycin (ERY), a macrolide belonging antibiotic is at the top of this list with its concentrations ranging between ng/L to a few µg/L in various global waterbodies giving rise to ERY-resistance genes (ERY-RGs) and ERY- resistance bacteria (ERY-RBs) posing serious threat to the aquatic organisms. ERY seems resistant to various conventional water treatments, remained intact and even increased in terms of mass loads after treatment. Enhanced oxidation potential, wide pH range, elevated selectivity, adaptability and greater efficiency makes advance oxidation processes (AOPs) top priority for degrading pollutants with aromatic rings and unsaturated bonds like ERY. In this manuscript, recent developments in AOPs for ERY degradation are reported along with the factors that affect the degradation mechanism. ERY, marked as a risk prioritized macrolide antibiotic by 2015 released European Union watch list, most probably due to its protein inhibition capability considered third most widely used antibiotic. The current review provides a complete ERY overview including the environmental entry sources, concentration in global waters, ERY status in STPs, as well as factors affecting their functionality. Along with that this study presents complete outlook regarding ERY-RGs and provides an in depth detail regarding ERY's potential threats to aquatic biota. This study helps in figuring out the best possible strategy to tackle antibiotic pollution keeping ERY as a model antibiotic because of extreme toxicity records.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Antibacterianos , Ecosistema , Eritromicina , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
11.
Environ Sci Pollut Res Int ; 28(20): 25939-25948, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33483925

RESUMEN

Sampling is a critical step in pesticide atmospheric analysis. Passive sampling offers advantages of inexpensive and convenient air monitoring. Polyethylene films (PE) were used as a passive sampler at multiple heights in greenhouse and agricultural field for 15 days to trap atmospheric chlorothalonil and lambda-cyhalothrin in the months of May and July. Among the two PE film thicknesses (20 and 80 µm), 20 µm PE was the most effective at absorbing target pesticides from air and attains equilibrium stage earlier than 80 µm PE film. After approximately 240 h of PE exposure in greenhouse and fields, chlorothalonil and lambda-cyhalothrin reached an equilibrium stage of partitioning between air and PE. Atmospheric concentrations of chlorothalonil (p < 0.01) and lambda-cyhalothrin (p < 0.001) at 1.5 m height were higher with the concentrations of 1855.59 ± 243.85 ng/m3 and 3682.11 ± 316.71 ng/m3, respectively, in the month of May as compared to the other three respective heights. The concentrations of chlorothalonil in air at 2 m height (1587.27 ± 284.19 ng/m3) were slightly higher than 0.5 m (1392.28 ± 205.09 ng/m3). Atmospheric concentrations of lambda-cyhalothrin at 2 m (3178.26 ± 299.29 ng/m3) were significantly lower than the other heights (p < 0.05). The greenhouse air concentrations of chlorothalonil and lambda-cyhalothrin in the months of May (1855.59 ± 243.85 and 3682.11 ± 316.71 ng/m3, respectively) and July (1749.33 ± 378.61 and 3445.08 ± 390.32 ng/m3, respectively) were higher than fields. The results indicate the usability of PE films to monitor chlorothalonil and lambda-cyhalothrin and potential other semi-volatile pesticides in agricultural fields.


Asunto(s)
Polietileno , Piretrinas , Monitoreo del Ambiente , Nitrilos , Piretrinas/análisis
12.
PLoS One ; 15(11): e0241705, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33142315

RESUMEN

Plant species of the Poaceae family are not only used as fodder and forage but also contribute substantially to the treatment of various health disorders, particularly in livestock. Consequently, the present study was aimed to document the therapeutic uses of Poaceae practiced by the inhabitants of the Punjab Province for the treatment of various veterinary health disorders. Semi structured interviews, group discussion and field walks were conducted to collect the data. Quantitative indices including cultural significance index (CSI), relative frequency of citations (RFC), fidelity level (FL), relative popularity level (RPL), and Jaccard Index (JI) were used for the data analysis. Traditional uses of 149 species belonging to 60 genera and 16 tribes of 5 sub families of Poaceae were recorded. Whole plants and leaves were the most consistently used parts with 40.94 and 29.53%. The plants were mainly given orally as fodder (59 reports) without processing followed by decoction (35 reports). Most of the species were employed to treat infectious diseases (25.93%), and digestive disorders (14.10%). Triticum aestivum had the highest CSI, RFC and RPL levels at 8.00, 0.96, 1.00, respectively, followed by Oryza sativa and Poa annua. Likewise, T. aestivum and Saccharum spontaneum had 100% FL and ROP. Jaccard index ranged from 12.25 to 0.37. Twelve plant species namely Chrysopogon zizanioides (anti-inflammatory), Pennisetum lanatum (improve bull fertility), Cymbopogon citratus (glandular secretion), Sorghum saccharatum and Themeda triandra (malaria), Aristida funiculate (anticancer), Koeleria argentia (skin allergies), Tetrapogon villosus (antibacterial), Cynodon radiatus (eyes infection), Sporobolus nervosa (Jaundice), Enneapogon persicus (antifungal), and Panicum repens (dysfunctional cattle organs) were reported for the first time, with novel ethnoveterinary uses. The inhabitants of the study area had a strong association with their surrounding plant diversity and possessed significant knowledge on therapeutic uses of Poaceae to treat various health disorders in animals. Plant species with maximum cultural and medicinal values could be a potential source of novel drugs to cure health disorders in animals and human as well.


Asunto(s)
Medicina Tradicional/métodos , Poaceae/química , Animales , Enfermedades Transmisibles/tratamiento farmacológico , Enfermedades del Sistema Digestivo/tratamiento farmacológico , Plantas Medicinales/química
13.
Environ Pollut ; 266(Pt 3): 115419, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32829033

RESUMEN

Road dust samples from industrial, urban, and tourist areas of the international tourist city of Guilin, China, were collected to study the concentration, spatial distribution, pollution level, and health risk of potentially toxic elements (PTEs) using an array-based risk assessment model from the United States Environmental Protection Agency. The geoaccumulation index (Igeo), ecological risk index, and spatial interpolation were used to investigate the road dust pollution level. The results indicated that apart from Ni and Al, the concentration of all the heavy metals (Pb, Zn, Ni, Cu, Cr, Cd, Fe, Mn, and As) were markedly higher than the corresponding background values in the three functional areas. Based on the Igeo, the study area had an uncontaminated to moderate pollution level, and the industrial area was slightly more polluted and posed a greater ecological risk than the urban and tourist areas. Comparatively, Pb, Zn, and Cu exhibited higher pollution levels in the three functional sites. Hotspots of PTEs were more concentrated in urban and industrial areas than in tourist areas. Furthermore, the health risk model revealed significant non-carcinogenic risks to children from As in urban, industrial, and tourist areas as the hazard quotients (1.64, 2.04, and 1.42, respectively) exceeded the threshold standard of 1.00. The carcinogenic risk via ingestion (RIing) illustrated significant risks to children from Cr, As, and Ni because the RIing values were considerably higher than the threshold standard (1.00E-6 to 1.00E-4) in the three functional areas. However, no cancer risk was observed from the dermal and inhalation pathways.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Niño , China , Ciudades , Polvo/análisis , Humanos , Medición de Riesgo
14.
Environ Sci Pollut Res Int ; 27(10): 11164-11173, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31956951

RESUMEN

The priority feature of coal drying which accounts for its industrial use is moisture removal. Though much improvement is made in thermal-drying process, volatilization of harmful elements during coal slime drying is mostly ignored which has manifold environmental implications. In view of this, the present study attempted to investigate the moisture and selenium (Se) volatilization proportion during coal slime drying by using electric blast oven (conventional) and microwave oven (microwave) drying procedures. X-ray photoelectron spectroscopy (XPS) technique was employed to investigate the chemical changes of raw and dried coal. The results indicated that the microwave-drying process eliminates the moisture in line format, whereas, moisture content was removed slowly (initial stage) during conventional drying and then rapidly (final stage) with increasing drying period. It was confirmed that the microwave drying took less drying time to remove water and make the coal dried compared with the conventional drying. Volatilization proportion of Se to the atmosphere was 38.81 and 61.13% during conventional and microwave drying, respectively. Findings of XPS analysis demonstrated an increase in C-C and C-H content, while a decrease in C-O fraction on the coal surface, after execution of drying procedures. Microwave drying appeared not only energy efficient but also proved an optimized method for removing oxygen-functional groups than conventional drying methods. Peak fittings of XPS spectra gave indication of several oxidation forms including selenide, selenate, and oxide species in coal slime after drying. It was concluded that Se volatilization including speciation characteristics should be considered an indicator of efficiency for coal drying process from environmental safety perspective.


Asunto(s)
Carbón Mineral , Selenio , Desecación , Microondas , Volatilización
15.
J Hazard Mater ; 365: 186-195, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30439618

RESUMEN

The study was undertaken to investigate deposition behaviors of various size-segregated particles and indoor air quality using dust accumulated on the air conditioner filter acting as a sink for PTEs and nanoparticles that can pose a significant health risk. However, the particulate matter size and chemical composition in AC dust and its relationship with PTEs remains uncertain. Current study aims to investigate the PTEs and nanoparticles composition of AC dust using different analytical approaches including ICP-MS, XRD, XPS, SEM/TEM along with EDS and Laser Diffraction particle size analyzer. The mean concentration of PTEs like Al, As, Cd, Cu, Li, Pb, Sb, Se, Sn, Ti, V and Zn exceeded the corresponding background value. Pb, As, Sn, Sb, Cd were categorizing under geo-accumulation index class IV. Most of the particles were found to be > 100 µm and it decreased significantly with increase in floor altitude. A significantly negative correlation was found between particles size and PTEs concentration showing a significant increase in PTEs content with decrease in particles size. The XPS results showed dominant peaks for TiO2, Ti-O-N, As2O3, Fe+3, Fe+2, Al-OH and Al203. Additionally, As, Pb, Si and Fe were dominant metallic nanoparticles identified using SEM/TEM along with EDS.

16.
RSC Adv ; 8(46): 25983-25996, 2018 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35541944

RESUMEN

Recently, nanosized metal-oxides have been extensively investigated for their ability to remove metal ions from aqueous media. However, the activity and capacity of these nanosized metal-oxides for removing metal ions decrease owing to their agglomeration in aqueous media. Herein, we synthesized a highly stable and magnetically separable rosin-biochar-coated (RBC) TiO2@C nanocomposite through a facile and environment-friendly wet chemical coating process, followed by a one-step heating route (pyrolysis) for efficient removal of Cr(vi) from aqueous solution. An array of techniques, namely, TEM, HRTEM, TEM-EDS, XRD, FTIR, VSM, BET and TGA, were used to characterize the prepared nanocomposite. The pyrolysis of rosin into biochar and the fabrication of Fe onto the RBC-TiO2@C nanocomposite were confirmed by FTIR and XRD examination, respectively. Moreover, TEM and HRTEM images and elemental mapping using TEM-EDS showed good dispersion of iron and carbon on the surface of the RBC-TiO2@C nanocomposite. Sorption of Cr(vi) ions on the surface of the RBC-TiO2@C nanocomposite was very fast and efficient, having a removal efficiency of ∼95% within the 1st minute of reaction. Furthermore, thermodynamic analysis showed negative values of Gibb's free energy at all five temperatures, indicating that the adsorption of Cr(vi) ions on the RBC-TiO2@C nanocomposite was favorable and spontaneous. Conclusively, our results indicate that the RBC-TiO2@C nanocomposite can be used for efficient removal of Cr(vi) from aqueous media due to its novel synthesis and extraordinary adsorption efficacy during a short time period.

17.
Chemosphere ; 191: 704-720, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29078193

RESUMEN

The use of fluoroquinolones (FQs) antibiotics as therapeutic agents and growth promoters is increasing worldwide; however their extensive uses are also resulting in antibiotic resistance among world communities. FQs have also become one of the major contaminants in the waste water bodies, which are not even completely removed during the treatment processes. Furthermore, their abundance in agricultural resources, such as the irrigation water, the bio-solids and the livestock manure can also affect the soil micro-environment. These antibiotics in soil tend to interact in several different ways to affect soil flora and fauna. The current review endeavors to highlight the some critical aspects of FQs prevalence in the environment. The review presents a detailed discussion on the pathways and abundance of FQs in soil. The discussion further spans the issue of sorption and FQs transformation into the soil better understand of their behavior and their toxicity to soil flora and fauna.


Asunto(s)
Antibacterianos/análisis , Fluoroquinolonas/análisis , Contaminantes del Suelo/análisis , Agricultura , Antibacterianos/metabolismo , Antiinfecciosos , Monitoreo del Ambiente , Contaminación Ambiental , Estiércol , Suelo , Aguas Residuales
19.
Environ Sci Pollut Res Int ; 24(21): 17881-17887, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28616739

RESUMEN

This is the first study from Pakistan to report the exposure of petrol filling workers (n = 120) to naphthalene (Nap) and pyrene (Pyr) in relation to their functional capacities and health outcome. A group of non-exposed subjects (controls n = 46) was also recruited for comparison. The perceived health risk of the exposed workers was monitored using a questionnaire based on the self-reporting survey. The observed physical anomalies related to the health disorder included the acidity after meals, eye redness, appetite loss, skin lesions, and dryness of oral cavity, while those related to neurasthenic symptoms included the body aches, energy loss, twitching, fatigue, sleeplessness, fainting, and irritability. Mean Nap level observed in the exposed group (106 µg L-1) was significantly correlated (r = 0.49; p < 0.01) with cigarette smoking, while the average Pyr concentration (19.18 µg L-1) was associated with job duration. Workers exposed for 6 h per day or more had significantly high prevalence of physical disorders (OR = 2.79, 95% CI = 1.28-6.09). Neurasthenic symptoms were found in 65% of the subjects and were associated with years of involvement in job. Ten years or more work duration at petrol pumps could be associated with a substantial development of neurasthenic effects (OR = 2.80, 95% CI = 1.23-6.34). In conclusion, the subjects ascribed the disturbances in physical and neurological behavior to their occupation (petrol filling) and also rated their overall health and functional capacity as poor. To promote health of petrol pump workers, reduction in work hours and provision of masks and gloves could be introduced as occupational health interventions.


Asunto(s)
Gasolina , Exposición Profesional , Salud Laboral , Estudios de Casos y Controles , Ciudades , Humanos , Pakistán
20.
Environ Toxicol Pharmacol ; 52: 14-20, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28364637

RESUMEN

The unchecked production and use of fluoroquinolones (FQs) for the treatment of infections in human and livestock has increased in Pakistan, which resulted in large amount of antibiotics in water bodies. In the current study, the prevalence and associated ecological risk of three FQs were investigated in waste-water bodies and sludge samples of Kahuta and Hattar industrial zones. The average concentrations of ciprofloxacin (CIP), enrofloxacin (ENR) and levofloxacin (LEV) in the waste-water samples were slightly higher in Kahuta (i.e. 58, 32.9, and 36.7µgL-1 respectively), than those in Hattar sites (i.e. 42.1, 41.2, and 48.9µgL-1 respectively). However, the concentrations of CIP, ENR and LEV in the sludge samples were significantly higher (i.e. 159; 153 and 164µgkg-1 respectively) in Hattar sites, compared to those in Kahuta sites (i.e. 129, 58 and 91µgkg-1 respectively). The uses of FQs in the health sector resulted in water pollution and poses the ecological risk to aquatic organisms. The individual risk associated with CIP was highest in Kahuta industrial sites for green algae ranging (2900-9100) followed by M. aeruginosa (5800-18200), cyanobacteria (580-18204) and invertebrates (24.2-75.8). These values suggested that the prevalence of antibiotics in the waste-disposal sites could be potential risk for the aquatic ecosystem, and harmful to biodiversity.


Asunto(s)
Antibacterianos , Fluoroquinolonas , Aguas Residuales , Contaminantes Químicos del Agua , Animales , Antibacterianos/análisis , Antibacterianos/toxicidad , Chlorophyta/efectos de los fármacos , Cianobacterias/efectos de los fármacos , Daphnia/efectos de los fármacos , Monitoreo del Ambiente , Peces , Fluoroquinolonas/análisis , Fluoroquinolonas/toxicidad , Invertebrados/efectos de los fármacos , Pakistán , Medición de Riesgo , Aguas Residuales/análisis , Aguas Residuales/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
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