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1.
Environ Geochem Health ; 45(5): 1635-1653, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35567675

RESUMEN

South Pars Industrial Energy Zone, located in the southwest of Iran along the Persian Gulf coast, encompasses many industrial units in the vicinity of urban areas. This research study investigated the effects of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) on human health and the environment. Suspended particulate matters (SPM) in the air sampled, in summer and winter 2019, from ten stations next to industrial units and residential areas. The samples were analyzed by gas chromatography-mass spectrometry (GC-MS). Spatial distribution maps of pollutants in the region were prepared using GIS software. The highest carcinogenic risk due to PAHs and PCBs measured as ([Formula: see text]) and ([Formula: see text], respectively. According to the US Environmental Protection Agency limit ([Formula: see text]), the cancer risks from PAH compounds were significant and need further investigation. The PCB cancer risks were within acceptable ranges. The highest adsorption ratios for PAHs were obtained through skin and PCBs by ingestion. The maximum measured non-carcinogenic hazard indexes (HI) turned out to be 0.037 and 0.023 for PAH and PCB, respectively, and were reported as acceptable risks. The predominant source of PAH in industrial areas was liquid fossil combustion, and in urban areas replaced by coal-wood-sugarcane combustion. Petrochemical complexes, flares, power plants (69%), electric waste disposal sites, and commercial pigments (31%) were reported as PCB sources. Industries activities were the most effective factors in producing the highest level of carcinogenic compounds in the region, and it is necessary to include essential measures in the reform programs.


Asunto(s)
Contaminantes Atmosféricos , Neoplasias , Bifenilos Policlorados , Hidrocarburos Policíclicos Aromáticos , Compuestos Policíclicos , Humanos , Bifenilos Policlorados/análisis , Compuestos Policíclicos/análisis , Compuestos de Bifenilo/análisis , Monitoreo del Ambiente/métodos , Irán , Polvo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Carcinógenos/toxicidad , Carcinógenos/análisis , Neoplasias/inducido químicamente , Neoplasias/epidemiología , Carbón Mineral/análisis , Medición de Riesgo , Carcinogénesis , Contaminantes Atmosféricos/análisis
2.
Environ Geochem Health ; 45(7): 4425-4437, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36811701

RESUMEN

Microplastics (MPs) contamination in the marine environment is a global threat. The present study is the first to comprehensively investigate the MPs contamination in the marine environment in Bushehr province along the Persian Gulf. For this purpose, 16 stations were selected along the coast and 10 fish samples were collected. The results obtained from MPs in sediment samples indicate the mean abundance of MPs in different sediment samples was 57.19 Particles/Kg. The dominant MPs color in sediment samples was black, accounting for 47.54%, followed by white (36.07%). As for MPs in fish, the highest MPs digested in different fish samples were 9. In addition, over 83.3% of MPs observed in fishes were black followed by red and blue (6.67%). Overall, the presence of MPs in fish and sediment can be attributed to improper disposal of industrial effluents; an efficient measurement is required in order to improve the quality of the marine environment.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Plásticos , Irán , Océano Índico , Sedimentos Geológicos , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Peces
3.
Environ Monit Assess ; 194(2): 118, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35072808

RESUMEN

Benzene, toluene, ethylbenzene and xylene (BTEX) are a challenging group of volatile organic compounds in industrial and energy areas. Since these aromatics may cause serious diseases such as cancer and respiratory illnesses, they must be monitored. Pars Special Economic Energy Zone (PSEEZ) in Iran is the second largest energy zone of the world with numerous gas refineries and petrochemical complexes for producing a wide range of products. This study is focused on determination of BTEX concentration in the whole South Pars area (46 sampling points) which is the active site of PSEEZ using passive sampling. Then, the results of the passive sampling are used for providing spatial distribution of BTEX using GIS. The annual BTEX measurements revealed that benzene and toluene concentration violates the maximum permitted values at numerous points most of which are located in the vicinity of petrochemical complexes. Active sampling in these complexes not only confirms the results of passive sampling, but also suggests a more intensified BTEX pollution in the air quality of the area which reaches as high as 3500 µg.m-3 and 18,000 µg.m-3 for benzene and toluene, respectively, being far beyond the acceptable standards. Health risk analysis also confirms the intensity of BTEX at the selected points. This study suggests a reconsideration of the location of non-operational sites and personnel who are more vulnerable to BTEX contamination. Also, BTEX profile provided by GIS in this research gives a suitable plan for relocating.


Asunto(s)
Contaminantes Atmosféricos , Xilenos , Contaminantes Atmosféricos/análisis , Benceno/análisis , Derivados del Benceno/análisis , Monitoreo del Ambiente , Medición de Riesgo , Tolueno/análisis , Xilenos/análisis
4.
Environ Monit Assess ; 195(1): 157, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36441256

RESUMEN

South Pars Industrial Zone is located near an Assaluyeh city on the coast of the Persian Gulf and is known as the energy capital of Iran. In this study, environmental and health effects due to PCB congeners had an assessment. In this study, 10 air stations, 10 seawater, and sediments stations were systematically selected and sampled in two seasons. Air, seawater, and sediment pollution made by polychlorinated biphenyls (PCBs) were evaluated. Seawater-sediment exchange conditions using the fugacity coefficient reviewed. PCB levels in marine sediments, seawater, and air based on the analysis of the obtained data were 107.33-172.92 ng/g, ND-135.68 ng/L, and ND-4.4 ng/m3, respectively. The highest concentration was observed in the vicinity of refineries, petrochemicals, and petroleum export facilities. These values had increased significantly compared to values of studies, conducted in similar areas. The sources were electrical wastes, storage sites, power generation units, and wastewater treatment. The ecological risk of seawater was assessed to be low to high, while sediment risks were reported with a low to moderate risk range. In 70% of the stations, the predominant transfer was from sediments to seawater; sediments were in fact the secondary source of seawater pollution. It is suggested for the area to be continuously monitored, while engineering and management measures should be adopted to improve the situation and also prevent the spread of pollution.


Asunto(s)
Bifenilos Policlorados , Agua , Irán , Monitoreo del Ambiente , Industrias
5.
Environ Res ; 198: 111260, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33939979

RESUMEN

The present investigation was designed to remove ibuprofen from aqueous solutions and wastewater by activating hydrogen peroxide using ultrasonication (US)/ultraviolet (UV) radiation/zeolite-titanium. The physical-chemical properties of the photocatalyst were determined using BET, FTIR, XRD, FESEM, and EDX-mapping techniques. The titanium oxide crystal size and the catalyst BET were determined to be 4.97 nm and 39.88 m2/g, respectively. Tests were performed in a reactor (with a volume of 316 mL) located in an ultrasonic bath to intensify reactions. The synergistic impact of the components of the UV/US/H2O2/Photocatalyst system was explored. The maximum efficiency (99.58%) was obtained at H2O2 concentration of 0.05 mM, pH 5, UV power of 6 W, photo-catalyst dose of 1 g/L, and contact time of 100 min. The pH variable was more effective than the other parameters. Ions of NO3-, Cl-, and SO42- had a slightly negative effect on contaminant removal efficiency. The ibuprofen removal (based on COD) from urban water and hospital wastewater was attained 77.82% and 66.24%, respectively. The ibuprofen removal by the developed system followed the first-order kinetic. The results show that the system has high efficiency and reasonable costs (with treatment cost of 6.25 €/m3) for ibuprofen decontamination.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Zeolitas , Peróxido de Hidrógeno , Ibuprofeno , Sonicación , Rayos Ultravioleta , Aguas Residuales , Agua , Contaminantes Químicos del Agua/análisis
7.
Environ Monit Assess ; 185(12): 9871-88, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23797635

RESUMEN

One hundred and thirty composite soil samples were collected from Hamedan county, Iran to characterize the spatial distribution and trace the sources of heavy metals including As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn, and Fe. The multivariate gap statistical analysis was used; for interrelation of spatial patterns of pollution, the disjunctive kriging and geoenrichment factor (EF(G)) techniques were applied. Heavy metals and soil properties were grouped using agglomerative hierarchical clustering and gap statistic. Principal component analysis was used for identification of the source of metals in a set of data. Geostatistics was used for the geospatial data processing. Based on the comparison between the original data and background values of the ten metals, the disjunctive kriging and EF(G) techniques were used to quantify their geospatial patterns and assess the contamination levels of the heavy metals. The spatial distribution map combined with the statistical analysis showed that the main source of Cr, Co, Ni, Zn, Pb, and V in group A land use (agriculture, rocky, and urban) was geogenic; the origin of As, Cd, and Cu was industrial and agricultural activities (anthropogenic sources). In group B land use (rangeland and orchards), the origin of metals (Cr, Co, Ni, Zn, and V) was mainly controlled by natural factors and As, Cd, Cu, and Pb had been added by organic factors. In group C land use (water), the origin of most heavy metals is natural without anthropogenic sources. The Cd and As pollution was relatively more serious in different land use. The EF(G) technique used confirmed the anthropogenic influence of heavy metal pollution. All metals showed concentrations substantially higher than their background values, suggesting anthropogenic pollution.


Asunto(s)
Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Suelo/química , Agricultura , Industrias , Irán , Análisis de Componente Principal , Análisis Espacial
8.
J Environ Health Sci Eng ; 21(2): 455-462, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37869597

RESUMEN

Purpose: Anaerobic-anoxic-aerobic process is one of the biological removal processes of nutrients in wastewater treatment. Phosphorus removal by biological method is a new and developed technique that is done by changing the design of suspended growth systems. Methods: This is a cross-sectional descriptive study, which is a pilot workshop based in the first module, and chemistry, physics and microbiological tests were carried out at the wastewater treatment plant laboratory in one of the cities (Pardis) of Tehran province in 2020-2021 during a period of 12 months. Was completed. In this research, a total of 500 samples were taken from raw wastewater, aeration pond, effluent, secondary sedimentation and return activated sludge. Results: In this research, the internal decay coefficient and the growth efficiency coefficient are equal to d-1 0.1264 and 0.6579 gVSS/gCOD, respectively. And the maximum specific rate of consumption of food substance and the semi-saturation constant of food substance respectively were gCOD/gVSS.d 3.3467 gCOD/m 25.305. If the specific rate of consumption of food substance or efficiency factor in our research is 0.27 gCOD/gVSS.d and the semi-constant Ks saturation equal to 27.9 gCOD/m has been obtained, this actually shows that the organic matter (COD) in the waste water of Pardis city had a higher degradability (sbCOD). Conclusion: According to the obtained results, the synthetic coefficients in the Lineweaver-Burk and Hanes models are suitable, but in the Hofstee model, the amount of K and Kd is less than the optimal amount for the proper exploitation of the pilot.

9.
Bull Environ Contam Toxicol ; 87(6): 674-7, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21956764

RESUMEN

Anzali and Gomishan wetlands are considered as two of the most important wetlands in southern coast of Caspian Sea. To investigate mercury accumulation in these ecosystems, total mercury concentrations were measured in the muscle tissue of two fish species. Higher mercury concentrations were detected in C. carpio, an omnivorous benthic/pelagic species (Anzali wetland: 0.2 µg g(-1) wet weight; Gomishan wetland: 0.2 µg g(-1) wet weight), than in S. lucioperca, a carnivorous pelagic species (Anzali: 0.06 µg g(-1) wet weight; Gomishan: 0.15 µg g(-1) wet weight).


Asunto(s)
Carpas , Monitoreo del Ambiente/métodos , Mercurio/farmacocinética , Percas , Contaminantes Químicos del Agua/farmacocinética , Animales , Ecosistema , Sedimentos Geológicos/química , Irán , Mercurio/análisis , Océanos y Mares , Contaminantes Químicos del Agua/análisis , Humedales
10.
Chemosphere ; 284: 131337, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34225119

RESUMEN

In this study, wasted sediment (sludge waste from shipping docks) was coupled with titanium isopropoxide by the thermal and sol-gel method as a new photocatalyst. The sediment-titanate catalyst alongside ultrasonic and UV was activated hydrogen peroxide to produce OH radicals and decompose cephalexin (CEP). The photocatalyst was crystalline with 52.29 m2/g BET area. The best destruction rate of 87.01% based on COD test was achieved at optimal conditions (pH: 8, cephalexin concentration: 100 mg/L, H2O2: 1.63 mg/L, UV: 15 W/m2, ultrasonication time: 100 min at 40 kHz, photocatalyst quantity: 1.5 g/L). The trend of anions effect was NO3- ≤ SO42- ≤ Cl-. Decomposition of cephalexin in water solution followed the first-order kinetics (k > 0.01 min-1, R2 > 0.9). The percentage of cephalexin removal from urban water (76%) and hospital wastewater (63%) has decreased compared to the distilled water solution (87%), which is probably due to the presence of radical inhibitors. The consumed electrical energy of the studied system was calculated by 0.031 kW/h. The developed system is a promising and economical method to remove cephalexin.


Asunto(s)
Cefalexina , Peróxido de Hidrógeno , Análisis Costo-Beneficio , Mejoramiento de la Calidad , Titanio , Ondas Ultrasónicas
11.
Environ Sci Pollut Res Int ; 28(40): 57099-57114, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34085196

RESUMEN

Novel copper-nickel ferrite nanocatalyst loaded on multi-walled carbon nanotube (MWCNTs-CuNiFe2O4) was synthesized and applied to activate peroxymonosulfate (PMS) in the degradation of the reactive black 5 (RB5). The structure of the catalyst was well characterized by scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD). The MWCNTs-CuNiFe2O4/PMS system showed a high performance in the degradation of RB5 with a kinetic rate of 1.5-2.5 times higher than homogeneous and heterogeneous systems. Maximum degradation efficiency (99.60%) was obtained at an initial pH of 7, catalyst dosage of 250 mg/L, PMS dosage of 4 mM, the temperature of 25 °C, and reaction time of 15 min. Anion experiments emphasized that the presence of nitrate, carbonate, and phosphate in the solution reduced the degradation efficiency by producing reactive species with low oxidation potential. The RB5 degradation rate evolved with temperature, and the activation energy was obtained to be 44.48 kJ/mol. The mechanism of PMS activation and production of free radicals was proposed based on tert-butyl alcohol (TBA), ethanol (EtOH), and potassium iodide (KI) scavengers. Trapping experiments showed that both sulfate (SO4•-) and hydroxyl (•OH) radicals are involved in the catalytic degradation of RB5. The effective treatment of real wastewater and tap water by the MWCNTs-CuNiFe2O4/PMS system requires a long reaction time. Gas chromatography-mass spectrometry (GC-MS) analysis indicated that RB5 can be degraded via methylation, decarboxylation, hydroxylation, and ring/chain cleavage pathways. The stable catalytic activity after three consecutive cycles suggested that MWCNTs-CuFe2O4 is a novel reusability catalyst in PMS activation.


Asunto(s)
Nanopartículas , Nanotubos de Carbono , Fenómenos Magnéticos , Naftalenosulfonatos , Peróxidos
12.
Ultrason Sonochem ; 67: 105122, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32276173

RESUMEN

In this study, a photo-catalyst of titanium oxide was coated on zeolite by the sol-gel method. The generation of the zeolite-titanate photo-catalyst was optimized at conditions of calcination temperature (300, 350, 400 and 500 °C), calcination time (1, 2, 3, and 4 h), and titanate content (0, 2, 4, 6, and 8 mL). The catalyst was used for 'Sonication/UV/H2O2″ activity and finally, eliminating ibuprofen. Physicochemical properties of the as-built photo-catalysts for all optimized conditions were determined using FESEM-EDX-mapping, BET, FTIR, and XRD. The highest percentage of ibuprofen removal (98.9%) was obtained at conditions of zeolite to titanium ratio of 1 g: 2 mL, time in the furnace of 1 h, and temperature of the furnace of 350 °C. The optimum photo-catalytic (namely, Cat-350-1-2) had a surface area value of 39 m2/g and a crystalline size of 4.9 nm. The surface area for all photo-catalysts increased after being used for ibuprofen removal, possibly due to ultrasonic waves. The presence of Ti-O, benzene ring, O-Al-O, O-Si-O, C-H, and O-H in the photo-catalysts structure were confirmed. Growing the calcination time resulted in an increase in the crystallinity of titanium dioxide in the photo-catalysts and, ultimately a reduction in the ibuprofen removal. The consumed energy by the developed system was calculated for the presence (0.094 kJ/g) and absence (17.5 kJ/g) of the ultrasonic wave. The degradation pathway and reaction kinetic are also explored and proposed. The results showed that the ultrasonic-UV-activated H2O2-based technique can be applied as an alternative method for ibuprofen removal from aqueous media.

13.
Ultrason Sonochem ; 65: 105062, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32172148

RESUMEN

The aim of the current study was directed to develop a new sea sediment/titanate photocatalyst to remove cephalexin from aqueous media in the presence of ultraviolet (UV) light, hydrogen peroxide (H2O2), and ultrasonic waves. The influence of furnace temperature (300, 350, 400, and 500 °C), furnace residence time (1, 2, 3, and 4 h), and ratio of sea sediment: titanium (0-6 v: w) on the physicochemical properties and the cephalexin removal by the sea sediment/titanate photocatalyst was explored. The technique of FTIR, SEM/EDX, XRD, BET, BJH, and Mapping was used to determine the physicochemical properties of the generated photocatalyst. The maximum cephalexin removal (94.71%) was obtained at the furnace temperature of 500 °C, the furnace residence time of 2 h, and the sea sediment: titanium ratio of 1:6 (=12 mL TiO2/2 g sea sediment). According to the acquired results, the surface area of the optimized catalyst, namely Cat-500-2-12, was computed to be 52.29 m2/g. The crystallite size of titanium oxide on the optimum photocatalyst was calculated ~17.68 nm. The FTIR test confirmed the presence of C=C, O-H, C=O, C-S, and C-H functional groups in the photocatalyst. The transformation pathway for the degradation of cephalexin by the developed system was drawn. The present investigation showed that the developed technique (sea sediment/titanate-UV-H2O2-ultrasonic) could be used as a promising alternative for attenuating cephalexin from aqueous solutions.

14.
Pak J Biol Sci ; 11(8): 1132-6, 2008 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18819552

RESUMEN

The objective of this study closely focuses on the settlement of the effect of marginal land use on plant diversity. The location of this study was Sar Firouze Abad region with rainfall of over 350 mm and slope of over 12%. Five treatments in terms of land use (exclusion area, grazed range, fallow, annual medic cultivation, wheat cultivation) done with the repetition of five times. The factors, such as the number of species, the number of plant bases in each species, the percentage of plant cover and biomass in each sampling were measured. The method used here is based upon complete randomized design applying Duncan test and Raunkiaer method for classification of plant species and also Shannon's diversity index of diversity and homogeny utilized. The results show that there are 76 species belonging to 60 genus and 19 families spreading in the region under study. The most dominant families are Fabaceae with 15 species covering 20% and Poaceae with 13 species covering 17%, respectively. According to Raunkiaer method the life form of the region species can be classified as Therophytes 66%, Geophytes 3%, Hemicryptophytes 26% and Chamaephytes 5%. The results also illustrate that the treatment of exclusion area has the most plant diversity, the percentage of plant cover and biomass in comparison with the rest of treatment cultivation and range grazed.


Asunto(s)
Agricultura , Biodiversidad , Biomasa , Plantas/clasificación , Análisis de Varianza , Geografía
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