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1.
Environ Sci Pollut Res Int ; 30(47): 103390-103404, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37697195

RESUMEN

To improve farming productivity, a large number of pesticides have been used worldwide in recent decades, leading to the pollution of soil, agri-products, and water, directly/indirectly affecting human health. In this regard, many studies were conducted in different countries on residual pesticides in the environment. In the current study, residual pesticides including chlorpyrifos, cypermethrin, diazinon, malathion, and metalaxyl in tomatoes were meta-analyzed and health risk of consumers was estimated. For this purpose, based on a systematic review, data from 47 studies were extracted and meta-analyzed, and the health impact of pooled concentrations was assessed via a health risk method. According to the results, metalaxyl had the most concentration followed by malathion, cypermethrin, diazinon, and chlorpyrifos, respectively. The non-carcinogenic risk (n-CR) was calculated from crop consumption also showed that exposure to malathion has the most risk. Among the investigated communities, Iranian consumers were in considerable health risk (THQ > 1). Considering that the potential for the use of pesticides will increase with the need for food in the future, hence, governments must manage the usage by governments via alternative methods such as cultural, biological, physical, and genetic modifications.


Asunto(s)
Cloropirifos , Plaguicidas , Solanum lycopersicum , Humanos , Plaguicidas/análisis , Cloropirifos/análisis , Diazinón/análisis , Malatión , Irán , Medición de Riesgo
2.
Heliyon ; 9(7): e17640, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37483757

RESUMEN

The reduction of traditional fuel sources and the unpredictability of the global economy have led to a push for renewable energy alternatives. Waste recycling can significantly reduce greenhouse gas emissions. In this study, the effects of different proportions of biochar on the efficiency of mesophilic anaerobic digestion of automotive paint sludge were investigated over a period of one month. A combination of paint sludge and anaerobic sludge in a ratio of three to one was used, and biochar was added to the anaerobic digestion reactor in two different amounts of 10 and 26 g/l, with a control sample without biochar. The cumulative volume of biogas produced at the end of the one-month experiment was recorded for three samples: the control sample (without biochar), the second sample (with 2 g of biochar), and the third sample (with 5.2 g of biochar). The volumes of biogas produced were 300, 380, and 530 ml, respectively. Additionally, the COD reduction rates were 25%, 33%, and 48%, and the VS decrement rates were 21%, 27%, and 43%, respectively. The findings showed that adding biochar to the anaerobic digestion reactor containing automotive paint sludge increased biogas production. Additionally, gas chromatography results for an optimal sample of biogas extracted from the anaerobic digestion reactor indicated the presence of about 50% methane gas. These results highlight the potential for utilizing biochar in anaerobic digestion processes to improve renewable energy production and waste management.

3.
Environ Sci Pollut Res Int ; 30(6): 14630-14640, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36161559

RESUMEN

In this study, simultaneous removal of an organic matter (diazinon, DIZ) and an inorganic substance (chromium, Cr) was used. Breaking down of organic matter by UV irradiation produces various radicals, including sulfides, carboxyl, hydroxyl, hydrated electrons, and various organic radicals that are highly reactive and help us to precipitation inorganic substance (Cr). The optimal condition was 30:1 DIZ:Cr molar ratio, pH 9, and about 100% and 82.3% of DIZ and Cr were obtained in 30 min. Cr deposition was very slow at first. After the destruction of the DIZ structure, Cr deposition began, and various types of sludge with disturbed properties were formed. These sledges were analyzed by FTIR analysis and showed that green sludge could be chromium (III) hydroxide; brown sludge due to chromium (III) hydroxide, tiny green crystals from chromium (III) oxide, red brick from chromium (II) acetate chromium trioxide, as well as black sludge caused by chromium oxide were identified. In UV/DIZ/Cr process, kobs and robs range obtained 0.33-0.15 and 16.8-23.4 $ with both Cr and DIZ concentration increased from 50 to 150 mg L-1. Also, EEO for Cr precipitation was 24.65 to 5.74 and for DIZ 12.54 to 4.73 (kwh m-3). Depending on the amount of energy consumption, TCS was 37.19 to 10.47 for Cr precipitation and 4.46 to 1.25 $. It is important to note that when both pollutants are exposed to ultraviolet light, more energy and cost are generally required from UV/DIZ process and less than of UV/Cr process. But it should be noted that in fact 50 mg L-1 of chromium and 50 mg L-1 of DIZ are being removed at the same time. In UV/DIZ and UV/Cr processes that are exposed to ultraviolet radiation alone, only one of them is removed. Also, when these two pollutants are being removed at the same time, the total amount of energy is much less than the total energy consumption of the pollutants one by one.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Aguas del Alcantarillado/química , Fotólisis , Diazinón , Rayos Ultravioleta , Oxidación-Reducción , Cromo/química , Contaminantes Ambientales/análisis , Contaminantes Químicos del Agua/análisis
4.
Environ Sci Pollut Res Int ; 30(1): 1562-1578, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35917072

RESUMEN

Amine modified pumice-derived silica aerogel (AMPDSA) was synthesized and grafted up to 6.52 [Formula: see text] with (3-aminopropyl) triethoxysilane for cefixime antibiotic adsorption. Using Response surface methodology, at the pH of 3, the maximum removal of cefixime of 80.42% for an initial concentration of 3.56 mg L-1 was achieved at an equilibrium time of 150 min. The compliance of various kinetic and isotherm models for the batch sorption system was corroborated from the correlation coefficient (R2) values. The maximum adsorption capacity of 19.76 mg g-1 and 49.63 mg g-1 was calculated for Langmuir and Khan isotherm models, respectively. The removal by fixed-bed column as a function of flow rate, initial cefixime concentration, and bed height was also performed. The maximum adsorption capacity of column with the bed height of 15 cm was found to be 31 mg g-1 at the flow rate of 10 mL min-1 for the initial concentration of 20 mg L-1. The compliance of Thomas model with the column sorption was observed. The characterization using SEM, BET, and XRD was carried out for the virgin and regenerated AMPDSAs. The regeneration experiments confirmed the ability of AMPDSA for its cefixime removal efficiency of 80% up to eight cycles.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Cefixima , Dióxido de Silicio , Adsorción , Antibacterianos , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Purificación del Agua/métodos
5.
Environ Sci Pollut Res Int ; 29(43): 64914-64923, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35476267

RESUMEN

Regarding the cost-effective photo-degradation of ofloxacin (OFL), present study investigates UV/sulfite /ZnO (USZ) in reactor conventional (without baffles) and baffled photocatalytic reactor (BPCR). The optimal condition was 0.77:2:50 sulfite/ZnO/OFL molar ratio, pH 7, and 30 min reaction time for 100% degradation of 200 mg L-1 concentration of OFL. As information obtained, the UZI process reduces the BOD and COD level about 66% to 86.29% within 80 min reaction, respectively. Also, BOD/COD ratio initial from 0.26 reaches 0.6 after 30 min of reaction time. Kinetic investigation increasing OFL concentration, kobs and robs increase, and, secondly, in the conventional and BPCR reactor, kobs increase is about 17% and 50% with increasing OFL concentration from 50 to 200 mgL-1. Also, figure-of-merit EEo varies from 12.66 to 17.41 and 7.26 to 10.15 kWhm3 for conventional reactor and 8.66-13.61 to 5.24-8.12 kWhm3, respectively. Also, kinetic model EEo declines from 15.23 to 8.61 and from 13.31 to 5.37 kWh m-3 in conventional and BPCR, respectively. Total cost of the system (TCS) decreases from 7.31 to 2.16 $ in conventional reactor and 4.57 to 0.55 $ in PCBR reactor. Total cost of the system (TCS) was investigated at different concentrations.


Asunto(s)
Contaminantes Químicos del Agua , Óxido de Zinc , Cinética , Ofloxacino , Sulfitos
6.
Ecotoxicol Environ Saf ; 212: 111986, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33540338

RESUMEN

Population exposure to environmental contaminants can be precisely observed through human biomonitoring studies. The present study aimed to systematically review all the biomonitoring studies conducted in Iran on some selected carcinogen environmental pollutants. In this systematic review study, 11 carcinogen agents were selected including arsenic, cadmium, chromium, nickel, lindane, benzene, trichloroethylene (TCE), pentachlorophenol (PCP), radon-222, radium-224, - 226, - 228, and tobacco smoke. The Web of Science, PubMed, and Scopus databases were searched for peer-reviewed articles published in English. After several screening steps, data were extracted from the studies. Meta-analyses (a random-effect model using the DerSimonian-Laired method) were performed only for the biomarkers with more than three eligible articles, including cadmium in blood and breast milk, and arsenic in breast milk. Methodological quality of the studies was assessed using the Newcastle-Ottawa Quality Assessment Scale adapted for cross-sectional studies. Of the 610 articles found in the database search, 30 studies were eligible for qualitative review, and 13 were included in the meta-analysis (cadmium in blood (n = 3), cadmium in breast milk (n = 6), and arsenic in breast milk (n = 4)). The overall pooled average concentrations (95% CI) of cadmium in blood, cadmium in breast milk, and arsenic in breast milk were 0.11 (95% CI: 0.08, 0.14), 5.38 (95% CI: 3.60, 6.96), and 1.42 (95% CI: 1.02, 1.81) µg/L, respectively. These values were compared with the biomarker concentrations in other countries and health-based guideline values. This study showed that there is a need for comprehensive action plans to reduce the exposure of general population to these environmental contaminants.


Asunto(s)
Monitoreo Biológico , Contaminantes Ambientales/análisis , Arsénico/análisis , Cadmio/análisis , Cromo/análisis , Estudios Transversales , Exposición a Riesgos Ambientales/análisis , Contaminación Ambiental/análisis , Femenino , Humanos , Irán , Leche Humana/química , Níquel/análisis
7.
J Environ Sci (China) ; 100: 167-180, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33279029

RESUMEN

The contamination of fish type products such as silver pomfret fish fillets by potentially toxic elements (PTEs) has raised global health concerns. Related studies regarding the concentration of PTEs in fillets of silver pomfret fish were retrieved among some international databases such as Scopus, PubMed and Embase between 1 January 1983 and 10 March 2020. The pooled (mean) concentration of PTEs in fillets of silver pomfret fish was meta-analyzed with the aid of a random-effect model (REM). Also, the non-carcinogenic risk was estimated via calculating the 95th percentile of the total target hazard quotient (TTHQ). The meta-analysis of 21 articles (containing 25 studies or data reports) indicated that the ranking of PTEs in fillets of silver pomfret fish was Fe (11,414.81 µg/kg wet weight, ww) > Zn (6055.72 µg/kg ww) > Cr (1825.79 µg/kg ww) > Pb (1486.44 µg/kg ww) > Se (1053.47 µg/kg ww) > Cd (992.50 µg/kg ww) > Ni (745.23 µg/kg ww) > Cu (669.71 µg/kg ww) > total As (408.24 µg/kg ww) > Co (87.03 µg/kg ww) > methyl Hg (46.58 µg/kg ww). The rank order of health risk assessment by country based on the TTHQ for adult consumers was Malaysia (2.500) > Bangladesh (0.886) > Iran (0.144) > China (0.045) > Pakistan (0.020) > India (0.015), while the corresponding values for child consumers was Malaysia (11.790) > Bangladesh (4.146) > Iran (0.675) > China (0.206) > Pakistan (0.096) > India (0.077). The adult consumers in Malaysia and children in Malaysia and Bangladesh were at considerable non-carcinogenic risk. Therefore, following the recommended control plans in order to reduce the health risk associated with the ingestion of PTEs via consumption of silver pomfret fish fillets is crucial.


Asunto(s)
Metales Pesados , Medición de Riesgo , Plata , Adulto , Animales , Niño , China , Monitoreo del Ambiente , Humanos , India , Irán , Malasia , Metales Pesados/análisis , Pakistán
8.
J Hazard Mater ; 377: 418-426, 2019 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-31176077

RESUMEN

The aim of this study is to develop the process relies on the UV irradiation of ZnO and I-, i.e. UV/ZnO /I- (UZI), to create both oxidizer and reducer agents simultaneously for photo-degradation of the Ciprofloxacin (CIP). This paper shows that while applying UV irradiation, UV/ZnO and UV/I- for 20 min can lead to achieve 37.5%, 58.12%, and 61.4% photo-degradation of 100 mg L-1 CIP at pH 7, respectively. Moreover, the UZI treatment can provide 91.54% photo-degradation efficiency. The LC-MS analysis of the UZI effluent indicates that 10 min process was adequate to degrade CIP into simple ring-shaped metabolites while 15 min treatment, mostly of CIP intermediates were linear and biodegradable organic compounds. Furthermore, fourteen little fragments were identified in the CIP photo-degradation via UZI, during the photoreaction time of 2.5 to 20 min. Then, a pseudo first-order kinetics equation was utilized to model the observed photo-degradation process. Finally, the computational results show that the increased concentration of the CIP solution from 100 to 400 mg L-1 decreases the observed rate constant (kobs) from 0.4125 to 0.2189 min-1 while increases the photoreaction rate (robs) from 41.25 to 87.56 mg L-1 min-1.


Asunto(s)
Ciprofloxacina/química , Ciprofloxacina/efectos de la radiación , Procesos Fotoquímicos , Algoritmos , Análisis de la Demanda Biológica de Oxígeno , Catálisis , Costos y Análisis de Costo , Depuradores de Radicales Libres , Radical Hidroxilo , Yoduros , Cinética , Sustancias Reductoras , Rayos Ultravioleta , Contaminantes Químicos del Agua/química , Óxido de Zinc
9.
Data Brief ; 19: 1600-1604, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30246077

RESUMEN

Contamination of environment, especially soil, is in great concern and can cause health problems. Thus, remediation of these pollutants through environmentally friendly methods should be considered. The aim of this data was bioremediation of TNT from contaminated soil. Two plastic pans were used as bioreactor. In each pan, 3 kg of soil was used. Concentration of TNT in contaminated soil was 1000 mg/kg. Rhamnolipid in concentration of 60 mg/l was added to intended pan. Sampling was done in each two weeks. In order to assessment of TNT degradation, samples were analyzed with HPLC. The data showed that after 154 days of experiment, TNT removal in soil that amended with rhamnolipid was 73% and in experiment with no addition of rhamnolipid was 58%. Based on the obtained data rhamnolipid was effective in remediation of TNT contaminated soil.

10.
Electron Physician ; 9(10): 5623-5630, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29238507

RESUMEN

BACKGROUND: Cleanup of areas contaminated by explosives is a public health concern. Some explosives can be carcinogenic in humans. Pentaerythritol Tetranitrate (PETN), a powerful explosive with very low water solubility, can be easily transported to ground waters. OBJECTIVE: This study was conducted to determine the removal efficiencies of PETN from soil by bioremediation, and obtain kinetic parameters of biological process. METHODS: This experimental study was conducted at the Environmental Health Engineering Lab (Isfahan University of Medical Sciences, Isfahan, Iran) in 2015-2016. In the present work, bioremediation of the explosive-polluted soils by PETN in anaerobic-aerobic landfarming method was performed. The influence of seeding and biosurfactant addition on bioremediation was also evaluated. The data were analyzed using Microsoft Excel software. RESULTS: The results show that, as the initial concentration of PETN increased, the lag phase was increased and the specific growth rate was increased up to 0.1/day in concentration of 50 mg/kg, and then it was decreased to 0.04/day. Subsequent decreases in specific growth rate can cause substrate inhibition. Seeding causes decrease in lag phase significantly. Biosurfactant addition had little to no impact on the length of lag phase, but biosurfactant plus seeding can increase the growth rate to 0.2/day, however, inhibitory effect of the initial concentration was started in very high concentration of PETN (150 mg/kg). CONCLUSION: Biosurfactant addition and seeding together have an impressive effect on biodegradation of PETN, furthermore seeding can enhance active microbial consortium and biosurfactant can improve the poor aqueous solubility of PETN, therefore making the substrate more accessible.

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