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1.
Environ Res ; 254: 118676, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38763285

RESUMO

In this study, magnetic CoFe2O4-PAC nanocatalysts were synthesized through facile hydrothermal and co‒precipitation approaches with ultrasonic irradiation, which were used for the treatment of hypersaline petrochemical wastewater (HPCW). When an ultrasound‒induced synthesis process (US@CoFe2O4‒PAC) was used, a more efficient and stable magnetic spinel CoFe2O4‒PAC nanocatalyst was developed. The application of this nanocatalyst as a PMS activator, not only caused eradication of 90.4% of chemical oxygen demand (COD) of a HPCW after 90 min reaction time under the optimum conditions (pH 5-6, catalyst dose 1.0 g/L and 1.0 mM PMS), but also led to marginal leaching of iron (314 µg/L) and cobalt (95 µg/L) from the nanocatalyst. Recycling experiments over five consecutive runs showed a negligible decrease (7.2%) in COD removal efficiency which proved the stability and reusability of magnetic US@CoFe2O4-PAC. Two main mechanisms of adsorption and catalytic oxidation processes (homogeneous and heterogeneous PMS) are involved simultaneously in the PMS/US@CoFe2O4-PAC system, which are responsible for the destruction of refractory contaminants of HPCW through the generation of SO4•‒ and OH• radicals. COD of HPCW was mainly removed through SO4•- radical attack (73.6%) and the biodegradability of HPCW was enhanced dramatically after 90 min reaction time. The germination index (GI) of raw HPCW was increased 17.1 ± 4.2% and 24.3 ± 8.8% after 15 and 90 min reaction time, respectively, even PMS/US@CoFe2O4-PAC system showed less impact on phytotoxicity mitigation. Hence, it can be recommended to dilute the effluent before using for irrigational purpose. The findings of this study present practical significance of spinel US@CoFe2O4-PAC, which is an environment‒friendly catalyst, easy to handle and can sustain long‒term operation for the treatment of recalcitrant hypersaline wastewater and the other potential practical applications.


Assuntos
Cobalto , Compostos Férricos , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Cobalto/química , Compostos Férricos/química , Catálise , Biodegradação Ambiental , Eliminação de Resíduos Líquidos/métodos , Salinidade
2.
Int J Environ Health Res ; 34(3): 1270-1283, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36787704

RESUMO

The lichen Usnea articulata collected from an unpolluted area was exposed for 6 months at 26 sites for the sample chosenusing a stratified random design, and the content of potentially toxic elements (PTEs) including As, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sn, V, and Zn, was assessed using ICP-MS. The health risk for both adults and children was then calculated using the PTEs concentrations. The results showed that despite the hostile urban conditions, transplanted lichens depicted clear deposition patterns of airborne PTEs, mostly associated with industrial sites, where As and other elements showed remarkably high values. The cumulative hazard index was below the risk threshold, both for adults and children. For the entire population (particularly children) residing in areas surrounding industrial sites, As and Cr appeared to be potentially carcinogenic elements.


Assuntos
Líquens , Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Metais Pesados/análise , Poluição Ambiental/análise , Solo , Medição de Risco , Poluentes do Solo/análise , China
3.
Int J Environ Health Res ; 34(2): 803-814, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36709497

RESUMO

Per- and polyfluoroalkyl substances (PFASs) such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are environmental contaminants with unfavorable impacts on human health and nature. This study aimed to determine the PFOA and PFOS concentration in water and fish samples from Karun, the largest river in Iran. According to the results, the PFOA and PFOS in water samples were 5.81-69.26 ng/L and not detected (n.d.)-35.12 ng/L, respectively. The dry season displayed higher concentrations in water samples than in the wet season. The maximum PFOS concentration measured was related to Barbus barbules sp. (27.89 ng/g). The human health risk assessment indicated minor risks (hazard ratio, HR < 1) from PFOA and PFOS through consuming contaminated drinking water and fish. Only HR value of PFOS in downstream area exceeded slightly 1.0, indicating potential health risk due to consumption of the river fish. Considering the average PFASs concentration, the risk quotients (RQs) showed low ecological risk.


Assuntos
Ácidos Alcanossulfônicos , Caprilatos , Água Potável , Fluorocarbonos , Poluentes Químicos da Água , Animais , Humanos , Irã (Geográfico) , Fluorocarbonos/toxicidade , Fluorocarbonos/análise , Medição de Risco , Peixes , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
4.
Environ Monit Assess ; 195(8): 917, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37402828

RESUMO

Trihalomethanes (THMs) are the first disinfectant by-products in the drinking water distribution network and are classified as potential carcinogens. The presence of THMs in chlorinated water depends on the pH, water temperature, contact time between water and chlorine, type and dose of disinfection, bromide ion concentration, and type and concentration of natural organic materials (NOMs). In the present study, the formation of THMs was evaluated by six simple and easy water quality parameters and modeled by an artificial neural network (ANN) approach through five water distribution networks (WDNs) and the Karoun River in Khuzestan province. The results of this study that was conducted from October 2014 to September 2015 showed that THM concentration ranged in five WDNs, including Shoushtar, Ahvaz (2), Ahvaz (3), Mahshahr, Khorramshahr, and total WDNs through N.D.-9.39 µg/L, 7.12-28.60, 38.16-67.00, 17.15-90.46, 15.14-29.99, and N.D.-156, respectively. The concentration of THMs exceeded Iran and EPA standards in many cases in Mahshahr and Khorramshahr WDNs. Evaluation of R2, MSE, and RMSE showed the appropriate correlation between measured and modeled THMs, indicating a reasonable ANN potential for estimating THM formation in water sources.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Trialometanos/análise , Qualidade da Água , Purificação da Água/métodos , Monitoramento Ambiental , Desinfecção/métodos , Cloro , Poluentes Químicos da Água/análise , Halogenação
5.
Int J Environ Health Res ; 33(1): 71-82, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34781808

RESUMO

Total petroleum hydrocarbons (TPHs) are common environmental pollutants in aquatic ecosystems that tend to adsorb onto the sediments. This study aimed to monitor the concentration and assessment of contamination level of TPHs in the sediments of Karun River and Bahmanshir estuary, which will eventually flow into the Persian Gulf. GIS-mapping technique was used to indicate the distribution of TPHs. The samples were collected during dry and wet seasons at 15 monitoring stations. - The maximum amount of TPHs was obtained at station No. 14 in the dry season (225.29 µg/g). The indices of determining the pollution source showed that hydrocarbons in polluted areas were mainly of biogenic origin. Compared to sediment quality guidelines (SQGs) and contamination factor (Cf), the study area sediments were in the conditions of moderate pollution and had a low ecological risk.


Assuntos
Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Estações do Ano , Ecossistema , Rios , Irã (Geográfico) , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Hidrocarbonetos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco
6.
J Environ Health Sci Eng ; 19(1): 319-330, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150238

RESUMO

This study investigates the concentrations of PM10-bound PAHs and their seasonal variations in three cities of Ahvaz, Abadan, and Asaluyeh in Iran. The mean concentrations of PM10 in two warm and cold seasons in Ahvaz were higher and in Abadan and Assaluyeh were lower than the national standard of Iran and the guidelines of the World Health Organization. The Σ16 PAHs concentration in ambient air PM10 during the cold season in Ahvaz, Abadan and Asaluyeh was 244.6, 633, and 909 ng m- 3, respectively, and during the warm season in Ahvaz, Abadan, and Asaluyeh was 242.1, 1570 and 251 ng m- 3, respectively. The high molecular weight PAHs were the most predominant components. The most abundant PAHs species were Pyr, Chr, B [ghi] P, and Flt. The results showed that the total PAHs concentration in the cold and warm seasons was dependent on industrial activities, particularly the neighboring petrochemical units of the city, vehicular exhausts, traffic and use of oil, gas, and coal in energy production. The total cancer risk values as a result of exposure to PAHs in ambient air PM10 in all three cities for children and adults and in both cold and warm seasons were between 1 × 10- 6 and 1 × 10- 4, and this indicates a potential carcinogenic risk. Therefore, considering the various sources of air pollutants and its role on people's health, decision makers should adopt appropriate policies on air quality to reduce the ambient air PAHs and to mitigate human exposure.

7.
J Environ Health Sci Eng ; 19(1): 851-866, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150277

RESUMO

This study reports temporal and spatial variations of 16 different species of particulate polycyclic aromatic hydrocarbons (particle-bonded PAHs) in the indoor and outdoor environments of three sampling sites in Bandar Mahshahr city, Iran. A low-volume air sampler was employed to collect size-segregated particulate matter during winter (October to December 2015), and summer (July to September 2016). The results showed that the annual concentrations of indoor and outdoor PM10 and PM2.5 were much higher than the related World Health Organization guidelines. The concentration of total particle-bonded PAHs (TPAHs) was higher in winter than in summer and a significant difference between the two sampling seasons was observed. The indoor and outdoor carcinogenic PAHs to TPAHs concentrations ratios in the sampling sites in summer and winter were as follow: for PM10 40.15-42.51%, PM2.5 41.30-42.97%, and PM1 43.07-44.36%, respectively; furthermore, the smaller the particle size, the higher the percentage of carcinogenic PAHs. 2 ring PAHs had a very small contribution to the total PAHs (about 1%), whereas PAHs with 3-to-4 rings had much larger contributions, ranging from 71.65% to 75.17%. The results demonstrated that as PM size decreased, the proportion of 5-to-6-ring PAHs to the total PAHs increased. Since 5-to-6- ring PAHs are considered to be more toxic, hence more attention should be paid to fine particles. The diagnostic ratios of indoor and outdoor of three sampling sites in both seasons suggested that petrogenic sources, as well as combustion of petroleum and other fossil fuels were the main PAHs sources.

8.
J Environ Health Sci Eng ; 19(1): 1069-1074, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150295

RESUMO

BACKGROUND AND PURPOSE: The Karoon River, located in southwest Iran, has always been considered as an important water source for people in the southward areas. Khuzestan Province is one of the strategic provinces of Iran thus the development of this province is significantly affected by the water pollution of the Karoon River system. Therefore, the current study aims to assess the environmental vulnerability of the Karoon River as well as preparing a classified map of its vulnerabilities using the fuzzy logic method via the geographical information systems (GIS). METHODS: In this study, the required data were gathered from the Water and Electricity Organization of Khuzestan Province. Afterward, the primary maps were created by converting the map of the study origin into a raster format. Then, fuzzy membership was performed by placing the digits in the range of zero and one using the fuzzy membership function. The primary maps were mixed, and finally, the risk map was prepared by applying the fuzzy overly function. RESULTS: According to the results, a clear trend of water quality deterioration exists since water moves from upstream to downstream areas. The ecological vulnerability of the Karoon basin is mostly located at a low-level (78.05 %) rank. The vulnerable areas were ranked extremely high, high, medium, and low as 2.09, 8.09, 12.08, and 78.05, respectively. CONCLUSIONS: Considering that 22 % of the Karoon River drainage basin in Khuzestan province is considered to have a medium to extremely high risk range, it is mandatory for the authorities to take precautions to prevent the entry of polluting sources into this precious river.

9.
Environ Geochem Health ; 43(8): 3229-3235, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33544269

RESUMO

From a public health point of view, years of life lost (YLL) is a more important index than the number of deaths to evaluate the effect of risk factors. The objective of the present study was to estimate the burden of disease including years of life lost (YLL) and expected life remaining (ELR) attributed to long-term exposure to PM2.5 in Ahvaz, one of the most polluted cities of the world, during March 2014 through March 2017. AirQ + software was used for the estimation of YLL and ELR due to all natural causes of death. Hourly concentrations of PM2.5 were acquired from the Department of Environment (DoE) of Ahvaz. Several steps were performed to validate the raw air quality data. Only the monitors were included that had minimum data completeness of 75%. Two age groups were selected for this study, including 0-64 and 65 < years. The life table approach was used to estimate YLL and ELR. Annual averages of PM2.5 were 5.2-8 times higher than the air quality guideline (10 µg/m3) set by WHO for long-term exposure to PM2.5. In total, PM2.5 has caused 234,041 years of life lost due to mortality. About 84% of YLLs were attributed to people older than 65 years old. The YLLs of men were higher than those for women. The YLLs in the third year were greater than the first two years. PM2.5 has caused the average age of total population, people aged 0-64 years old, and people > 65 years old decreased by 2.5, 3, and 1.6 years, respectively. These studies indicated that people in a city that the air quality is highly affected by dust storms, industrial emissions, and urban air pollution are significantly at risk. Air pollution control strategies and actions should be designed and executed to improve the quality of ambient air.


Assuntos
Material Particulado/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Cidades , Exposição Ambiental/análise , Feminino , Humanos , Masculino
10.
Mar Pollut Bull ; 160: 111569, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32861938

RESUMO

Recently, atrazine has been increasingly used to control weeds in the corn and sugarcane farms, which affects the water resources and aquatic organisms. In this study, atrazine residual concentrations in water and fish samples of the Shadegan wetland (Iran) were investigated. Furthermore, the health and ecological risk assessment were calculated. A total of fifty water samples were collected from the wetland during three periods with a four-month time interval. Also, ten samples of ten different fish species were analyzed at the same time. The estimation of acceptable daily intake and comparison with international standards indicates danger to adjacent residential areas of wetland. Non-carcinogenic risk analysis showed that total hazard quotient (HQing + HQderm) were below the acceptable limit and there is no danger to the residents of the area. Atrazine concentration in the water and fish samples ranged between 0 and 2175.8 µg/L, and 0 to 35.58 µg/L, respectively. Results showed that 88% of the water samples were higher than EPA and WHO guidelines for drinking water in summer. The concentrations of atrazine in fish samples in summer were more than other seasons. Analysis of ecological risk assessment also showed that considering the average atrazine concentration in three seasons, the risk exposure was very high. This study will be beneficial to the both residents and government officials in management of Shadegan wetland pollution in term of toxic compounds.


Assuntos
Atrazina , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Irã (Geográfico) , Medição de Risco , Poluentes Químicos da Água/análise , Áreas Alagadas
11.
Environ Sci Pollut Res Int ; 26(11): 10941-10950, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30783934

RESUMO

In recent years, concerns over the issue of air pollution have increased as one of the significant environmental and health problems. Air pollutants can be toxic or harmful to the life of plants, animals, and humans. Contrast to primary pollutants, ozone is a secondary pollutant that is produced by the reaction between primary precursors in the atmosphere. The average of air pollutant data was compiled for the purpose of analyzing their correlation with the pulmonary function of students and the FENO biomarker from the air pollutants of the Environmental Protection Agency. According to the average of 3 days, the concentration of ozone in the (S3) region was higher than the other regions, and this level was significantly different from the ANOVA test (p < 0.05). The results of artificial neural network modeling for three particular combinations in the cold season, two hidden layers with 9 and 12 neurons, with R2 = 0.859 and in the warm season, layer with 13 neurons, with R2 = 0.74, showed the best performance.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Óxido Nítrico/análise , Ozônio/efeitos adversos , Sistema Respiratório/efeitos dos fármacos , Poluentes Atmosféricos/análise , Biomarcadores/análise , Criança , Pré-Escolar , Expiração , Humanos , Irã (Geográfico) , Masculino , Redes Neurais de Computação , Ozônio/análise , Valor Preditivo dos Testes , Testes de Função Respiratória , Estações do Ano
12.
Pathol Res Pract ; 214(9): 1462-1466, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30104077

RESUMO

Long non-coding RNAs (lncRNAs), are lengthy noncoding transcripts with pivotal roles in biological pathways including cell cycle, apoptosis and chromatin remodeling. Aberrant expression of lncRNAs has been strongly connected with tumor progression and metastasis. However, the prognostic significance of lncRNAs in diffuse large-B-cell lymphoma (DLBCL) remains unclear. In this study, the expression levels of 189 approved lncRNAs were considered in DLBCL patients using several different genomic and transcriptome datasets. The analyses showed that the lncRNA GAS5 allocated the maximum score of RNA dysregulation and can be considered as good choice in DLBCLs' researches.


Assuntos
Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , RNA Longo não Codificante/genética , Simulação por Computador , Humanos , Transcriptoma
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