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Showing 706 results for Type of Study: Research
Assessment of efficient photocatalytic fenitrothion elimination from aqueous solution using magnetic graphene oxide functionalized with cerium dioxide nanocomposite
Seyed Khabat Naynava, Bahareh Lorestani, Mehrdad Cheraghi, Soheil Sobhanardakani, Behzad Shahmoradi,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Fenitrothion is a phosphorus-based pesticide that enters water resources through various sources,including industrial wastewater and agricultural effluent. its non-biodegradability, which results from the formation of strong chemical complexes, advanced oxidation methods are required to remove it from environmental matrices.  This study aimed to evaluate the performance of a magnetic graphene oxide nanocomposite functionalized with cerium dioxide in the removal fenitrothion from aqueous solution.
Materials and Methods: In this applied research, GO@Fe3O4@CeO2 was synthesized and subsequently used as a photocatalyst for the removal of Fenitrothion from aqueous solutions. Characterization of GO@Fe3O4@CeO2 was conducted using X-Ray Diffraction (XRD), Scanning Electronic Microscopy (SEM), SEM-EDX elemental analysis, Fourier transform infrared spectroscopy (FT-IR), and vibrating sample magnetometry (VSM) methods. The effects of various parameters, including pH (2-9), photocatalyst dosage (10-40 mg), and contact time (0-90 min), were assessed to determine their influence on fenitrothion removal efficiency. 
Results: The results demonstrated that the removal efficiency increased up to 60 min contact time, 20 mg of photocatalyst. The optimal pH for fenitrothion removal was found to be 4. Additionally, kinetic analysis of the photocatalytic removal process indicated that it followed a pseudo first-order (PFO) model.
Conclusion: The GO@Fe3O4@CeO2 nanocomposite proved to be an effective and accessible photocatalyst for the removal of fenitrothion from industrial wastewater under UV light.
 

Ecological and human risk assessment of some heavy metals in the dust of elementary schools in selected areas of Mashhad city
Hassan Malvandi,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Dust particles in urban environments are often contaminated with heavy metals, posing significant health risks, particularly to children. Schools are one of the environments where children are exposed to dust particles. Therefore, the aim of this study was to determine the concentration of heavy metals in the dust collected from Mashhad schools and to assess the associated health risks.
Materials and Methods: Dust samples were collected from 27 schools in the fall of 2022 using a brush.  The values of various indices were estimated, including the geoaccumulation index (Igeo), contamination factor (CF), pollution load index (PLI), enrichment index (EF), potential ecological risk index (PERI), and health risk indices such as hazard quotient (HQ) and hazard index (HI).
Results: The average concentrations of cobalt (Co), iron (Fe), calcium (Ca), aluminum (Al), lead (Pb), and barium (Ba) were 9.63, 18538.58, 84017.79, 11270.42, 32.07 and 111.56 µg/g, respectively. The Igeo values ranged from -3.69 to 1.51, while the CF values ranged from 0.16 to 4.26. The results of the pollution indices indicated that most of the studied elements were at the first level of pollution, suggesting that the degree of pollution was negligible or low. Additionally, the HQ and HI values were both less than 1.
Conclusion: Overall, the concentrations of the studied elements were not a concern, remaining at uncontaminated levels, and there was no potential health risk associated with exposure to these elements.
 

Determination of diazinon and cypermethrin levels in milk, cheese, and butter in Gonbad-Kavus city in 2021-2022
Farzad Kalteh, Mohammad Hosein Movassagh,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective:  The presence of pesticides in milk and dairy products poses a potential risk to consumers. The current study aimed to determine the concentrations of diazinon and cypermethrin in milk, cheese, and butter distributed in Gonbad-Kavus City.
Materials and Methods: A total of 50 samples including raw milk, pasteurized milk, ultra-high-temperature milk, traditional cheese, and traditional butter, were randomly collected from supply centers in Gonbad-Kavus from between 2021 and March 2022. The concentrations of diazinon and cypermethrin in the samples were measured using high-performance liquid chromatography (HPLC).
Results: The mean diazinon levels in raw milk, pasteurized milk, and ultra-high-temperature milk samples were 41.91 ± 9.68, 28.07 ± 5.86, and 40.21 ± 9.52 µg/kg, respectively. The mean cypermethrin levels in raw milk, pasteurized milk, and UHT milk samples were 34.06 ± 8.20, 22.63 ± 5.88, and 29.82 ± 8.09 µg/kg, respectively. Significant differences were observed among the sample types for both diazinon and cypermethrin levels. In cheese samples, the mean diazinon and cypermethrin levels were 57.23 ± 10.59 and 38.12 ± 8.69 µg/kg, respectively. In butter samples, the mean diazinon and cypermethrin levels were 16.77 ± 4.15 and 17.50 ± 6.47 µg/kg, respectively.
Conclusion: The results of the present study showed that the various types of milk distributed across Gonbad-Kavus contain excessive diazinon residues, while the residual cypermethrin levels were below the allowable limit. Therefore, a codified program to reduce diazinon the residuals in milk, cheese, and butter distributed in Gonbad-Kavus should be implemented.
 

Evaluation of the amount of acrylamide formation in crackers and wafers
Saeed Hoseini Majd, Seyed-Ahmad Shahidi, Nabi Shariatifar, Mohammad Ahmadi, Mahdi Sharifi Soltani,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Healthy food consists of beneficial components for health consumer and is free of harmful substances. Acrylamide (2-propenamide), a known carcinogen, is one such harmful substance. Foods like wafers and crackers can become contaminated with acrylamide during the cooking process. The aim of the present study was to measure acrylamide formation in crackers and wafers.
Materials and Methods: In this study, 64 wafer and cracker samples were prepared (in duplicate), and evaluated for acrylamide content using a GC-MS device.
Results: According to the results, the mean ± SD (minimum-maximum) acrylamide concentration in the samples was 2.648 ± 1.814 (0.132-4.505) mg/kg. The mean ± SD (minimum-maximum) concentration of acrylamide in wafer samples was 3.369 ± 1.735 (0.320-4.505) mg/kg, while in cracker samples, it was 1.446 ± 1.161 (0.132-2.955) mg/kg (p =0.001). Cocoa wafer with cocoa cream had the highest level of contamination among wafers (4.505 ± 0.73 mg/kg), and crispy salty cracker had the highest level of contamination among cracker samples (2.955 ± 0.63 mg/kg).
Conclusion: Since the average concentration of acrylamide exceeded European Union standards, further studies are warranted. Additionally, regulatory standards should be established in Iran to ensure factories adhere to stricter guidelines in this area.
 

Effect of EDTA on soil quality and growth and nutrients characteristics of the medicinal plant Marrubium cuneatum under potentially toxic elements stress
Sadegh Hosseinniaee, Mohammad Jafary, Ali Tavili, Salman Zare,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Ethylenediaminetetraacetic acid (EDTA) is known as a synthetic chelating agent used for the remediation of soils contaminated with potentially toxic elements. Marrubium cuneatum is a medicinal plant with phytoremediation capabilities. This study investigated the effect of EDTA on the morph-physiological characteristics of this species and its rhizosphere soil.
Materials and Methods: Under greenhouse conditions, M. cuneatum was grown for six months in mine-contaminated soil with different levels of EDTA (0, 1, 3, 5 mmol/kg).  Subsequently, its biomass, concentration of macro- and micronutrients, and soil biochemical properties—such as organic matter content, soil enzyme activity, and microbial biomass—were measured. Additionally, a regression model was established between EDTA concentration and shoot weight to predict the plant's growth response.
Results: A concentration of 5 mmol/kg EDTA decreased the dry weight of shoots and roots by 11% and 21.9%, respectively, compared to the control. The reduction in root macronutrient content was less pronounced with EDTA application compared to that of the shoots, with the greatest decrease observed for shoot potassium (40.70% compared to the control). The potassium-to-sodium ratio also decreased significantly. Despite improvements in some soil biochemical parameters at low EDTA levels, the 5 mmol/kg dose resulted in a 30% and 10% inhibition of urease and dehydrogenase activity, respectively. The regression relationship between EDTA concentration and shoot weight indicated that the maximum dry weight was obtained at a concentration of 2.4 mmol/kg.
Conclusion: Considering the adverse effects of EDTA at concentrations of 3 mmol/kg on soil and plants, as well as the predictive model of the growth response of M. cuneatum, it is suggested to investigate EDTA levels above 2.4 mmol/kg to determine the precise dose that initiates negative effects in soil and plants.
 
Evaluation of risk and pollution load of heavy metals (Fe, Zn, Pb, Cd, Cu, Mn, and Mo) in surface soil of Al-Qasim city, Babylon governate, Iraq
Jawad Kadhim Noor, Atefeh Chamani, Ahmed Najm Abdallh Al-Mosawy, Narges Kargari,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: The pollution of trace elements in urban soil has attracted wide attention due to its detrimental environmental and health effects. Therefore, this research was conducted to evaluate of the content, pollution levels, and health risks associated with trace elements (Fe, Zn, Pb, Cd, Cu, Mn, and Mo) in the surface soil of Al-Qasim City in Babylon Governate in 2024.
Materials and Methods: This descriptive cross-sectional study involved, a total of 50 surface soil samples from a depth of 0-20 cm. The elemental content of the samples was determined using inductively coupled plasma optical spectroscopy (ICP-OES). Additionally,, the enrichment factor (EF), pollution index (PI), pollution load index (PLI), hazard index (HI), and carcinogenic risk (CR) were calculated. Statistical data analyses were done using SPSS software. 
Results: The average concentrations of Fe, Zn, Cd, Cu, Mn, and Mo in the soil were 27240, 62.7, 0.302, 33.8, 570 and 0.999 mg/kg, respectively. The highest average concentrations of Fe (30,331 mg/kg), Cu (37.3 mg/kg), Mn (639 mg/kg), and Mo (1.08 mg/kg) were found in downtown areasm whilefor the highest concentrations of Zn (65.3 mg/kg) and Cd (0.332 mg/kg) were observed in rural and midtown areas.
Conclusion: The results of this research demonstrate the impact of urban activities—such astraffic, industry, and agriculture—on the trace element pollution in the soil of Al-Qasim City. Therefore, regular monitoring of trace element concentrations and identification of their pollution sources are recommended to reduce and manage associated environmental and health risks.
 

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