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Showing 47 results for Quality
Golin river water quality assessment in Kermanshah province using water quality index and river pollution index
Houshang Ghamarnia, Meisam Palash, Zoleikha Palash,
Volume 15, Issue 3 (12-2022)
Abstract
Background and Objective: Increasing the productivity of surface water, the unsustainable development of agriculture in the boundaries of rivers, and human sewage have reduced the quality of these water resources. Therefore, investigating the amount of pollution and its sources is very necessary for regional planning. This study aimed to evaluate the water quality of the Golin River using WQI and Liou indexes.
Materials and Methods: Sampling of Golin river water was performed to check water quality based on (WQI) and (Liou) indices in Najjar village station for one year from April 2019 to March 2020.
Results: Water quality, according to the Liou index, during the research period in the sampling station in September and March, was in a good category and other months were slightly polluted. According to the results of the WQI index, water quality in September and March were in the excellent descriptive category, with values of 47.82 and 49.74, respectively, but in other months it was in a good category. In September and March, water quality improved compared to other months because of lower BOD5 due to reduced agricultural activities, and both indicators showed these quality changes well.
Conclusion: Due to the lack of stable conditions in water quality affected by seasonal changes and its departure from the category of high-quality water according to the results of the WQI index and also a little water pollution according to the Liou index, the direct use of Golin River water for drinking purposes is recommended and for this purpose, regular purification should be done and accurate and continuous evaluations of water quality in Golin River are necessary.
 

Investigating the amount of heavy metals in compost produced in the compost industries of Mazandaran province
Mohammadali Zazouli, Samaneh Dehghan, Mahdieh Mohammadi Alashti, Afsaneh Fendereski, Reza Dehbandi,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: One of the main limitations of using compost is the possibility of heavy metals with high concentrations. Unlike organic contaminants, these elements resist decomposition by microorganisms and, when present at elevated levels, pose a toxicity risk to soil, plants, aquatic ecosystems, and human health.
Materials and Methods: This study was a descriptive cross-sectional study conducted in 2021-2022w. Samples were collected from three compost factories in Mazandaran (Babol, Behshahr, and Tonekabon) using random sampling methods and prepared according to the acid digestion method (National Standard Institute 5615). The concentration of heavy metals in the samples was measured using an ICP-OES.
Results: The average concentration of arsenic, zinc, lead, cadmium, cobalt, chromium, copper, and nickel in the analyzed samples were 1.38±3.47, 490±151.5, 74±12, 2.56±0.65, 4.5±1.46, 31.72±16.47, 186.11±49.9, 22.72±4.2 mg/kg dry weight of compost, respectively. The average concentration of heavy metals in different cities was compared using the Kruskal-Wallis test, based on which the concentration of heavy metals in none of the cities was significantly different from each other (p>0.05).
Conclusion: The concentration of heavy metals in the investigated compost samples was lower than the limits specified in both domestic and international standards. Therefore, the final product of the examined compost factories meets the health standards for heavy metals and is safe for use in environmental applications.
 

Investigating the physicochemical characteristics in edible oils produced by cold press and industrial methods in Sabzevar city
Ehsan Manavipour, Akbar Eslami, Abbas Shahsavani, Ahmad Alahabadi, Reza Saeedi, Fatemeh Shokri Dariyan, Mehrnoosh Abtahi,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: In today's society, preparing healthy food has become challenging due to the variety of food production methods. Oil is produced in several ways in our country. In the cold pressing method, there is insufficient monitoring of the manufactured product. The aim of the present study is to investigate the physicochemical characteristics and the levels of heavy metals of industrial oil compared to cold-pressed oil.
Materials and Methods: In this research, 54 samples of sunflower, sesame, and canola oil produced by both cold pressing and industrial refiningmethods were prepared. Their physicochemical characteristics, including refractive index, acid value, iodine value, saponification value, peroxide value, anisidine value, as well as the concentrations of lead, iron, arsenic and copper were determined. Additionally, the effect of storage time on these characteristics was investigated.
Results: The Iodine number showed the highest deviation from the standard (61%), with an average of 136.70 gI/100g for the cold-pressed oil and 134.48 gI/100g for industrially refined oiland. The average value of the physicochemical characteristics, except for the saponification value, were higher in the cold-pressed oil samples  compared to the industrially refined oil samples, but the observed difference was not statistically significant. An investigation into the effect of storage time on physicochemical properties revealed a significant increase in peroxide value (p<0.01) and anisidine (p <0.05) in both oil groups over a two-month period. The average concentration of arsenic, lead, iron and copper in the studied oils was 0.03, 0.78, 0.05 and 0.05 mg/kgoil, respectively. A deviation from the standard was observed only in one sample of cold-pressed sunflower oil, with an arsenic concentration of 0.11 mg/kgoil).
Conclusion: Based on the obtained results, the refined industrial oils exhibited more favorable chemical characteristics and stability.  It is suggested that cold-pressed oils should be consumed within a short period of time. For frying purposes, refined industrial oils are preferable.
 

Evaluation of the quality of unconventional water (wastewater treatment plant effluent) of Pakdasht city for Cucurbits irrigating in 2022
Abbas Khazaee, Mehrnoosh Abtahi, Mahsa Jahangiri-Rad, Fatemeh Shokri-Daryan, Mohammad Rafiee,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Identifying the quality of non-conventional waters and exploring their optimal utilization are fundamental measures for maintaining public health. This study aims to investigate the effluent quality of the irrigation canals in Pakdasht farms.
Materials and Methods: In this cross-sectional descriptive study, 120 samples were collected from 6 irrigation canals in Pakdasht fields over a period of 5 months. The physicochemical and microbial characteristics of the canal effluents were determined based on the standard methods of water and wastewater tests. The concentration of heavy metals was measured using an ICP device. To determine the possibility of using the effluent of Pakdasht canals for agricultural purposes, the Environmental Protection Organization of Iran and FAO standards were used.
Results: The average concentrations of COD, BOD5, TSS, TDS, NO3-, SO4-2, PO4-3 parameters were 259, 125, 105, 697, 4.5, 94.4, 13.5 mg/L. Additionally, the average number of total and fecal coliforms in the effluent of the canals exceeded the standard values set by IRNDOE and FAO. The mean pH was 6.97, the electrical conductivity (EC) was 1014 μm/cm, and the turbidity was 76.2 NTU. The detected concentrations of heavy metals were awithin the following ranges: Cr (0.025-0.045 mg/L), Cd (0.0006-0.001 mg/L), Pb (0.0006-0.001 mg/L), Co (0.038-0.059 mg/L), and Ni (0.05-0.06 mg/L), which were roughly lower than the suggested standards. However, both HEI and WWQI indices confirmed that the water was unsuitable for agricultural irrigation.
Conclusion: Based on the comparison of the results of the parameters measured in this study with the environmental and FAO standards, the effluent from the irrigation canals of Pakdasht city is deemed unsuitable for the irrigation of warm-season crops but suitable for fodder and industrial crops.
 

Evaluation of ambient air quality in Arak with emphasis on aggregate and health risk-based indices
Adel Sheykhan, Gholamreza Moussavi, Mohsen Heidari,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: The air quality index (AQI) does not account the interaction of multiple pollutants, meaning the high concentration and health risk of one pollutant may amplify the effects of others. The main aim of this study was to characterize the ambient air quality of Arak by assessing the combined effects and health risks associated with criteria air pollutants.
Materials and Methods: This study evaluated the ambient air quality of Arak for the year 1401 on the Persian Calendar, using the concentrations of criteria air pollutants averaged over appropriate timeframes. Additionally, the AQI, aggregate air quality index (AAQI), and health risk-based air quality index (HAQI) were calculated.
Results: Findings showed that the 1-hour concentrations of NO2, SO2, PM10, and PM2.5 exceeded national standards in 0.05%, 0.2%, 12.1%, and 35.5% of hours, respectively. The AQI, AAQI and HAQI values were above 100 in 54.4%, 77.3%, and 56.2% of hours, respectively. PM2.5 was the major pollutant in over 99% of cases.
Conclusion: The results indicated that AAQI and HAQI, in comparison to AQI, characterized the air quality as more polluted. This stricter assessment by AAQI and HAQI may encourage more precautionary measures by authorities and the public. Thus, it is recommended that the decision-makers in Iran’s air quality monitoring in consider adopting these indices.
 

Advanced evaluation of indoor air purification by plants: modeling the impact of Chlorophytum comosum and Aglaonema silver in benzene
Farzaneh Borzabadi Farahani, Mahmood Alimohammadi, Jamshid Rahimi, Sanaz Khoramipour, Emad Dehghanifard,
Volume 18, Issue 2 (9-2025)
Abstract
Background and Objective: People spend over 90% of their time indoors, where air pollutant concentrations—including volatile organic compounds (VOCs)—are significantly higher than outdoors. Among these VOCs, benzene is particularly critical due to its carcinogenic properties. Phytoremediation offers a sustainable solution for removing such pollutants from indoor environments. This study evaluates the benzene-reduction efficiency of two ornamental plant species, Aglaonema ‘Silver’ and Chlorophytum comosum, under controlled temperature and humidity conditions.
Materials and Methods: The plants were exposed to two temperature levels (18°C and 24°C) and two relative humidity conditions (35% and 50%). Benzene was introduced into sealed chambers at concentrations of 1, 0.5, 0.25, and 0.125 µL/mL. After 12 hours of exposure, benzene reduction was quantified using gas chromatography.
Results: At 20°C and 35% RH, Aglaonema 'Silver' removed 96% of benzene, outperforming Chlorophytum comosum (38%). Removal efficiency depended on species, environmental conditions, and initial concentration. Predictive models (Eq. 2–3) correlated strongly with experimental data (R² > 0.9).
Conclusion: Aglaonema 'Silver' demonstrated superior benzene removal compared to Chlorophytum comosum under lower temperature and humidity conditions. Our findings highlight that selecting plant species adapted to specific environmental parameters can significantly improve phytoremediation effectiveness. Furthermore, the proposed model indicates that elevated temperature and humidity levels may enhance benzene removal efficiency by indoor plants.
 

Investigation of the chemical and microbial parameters of sludge produced at the Khoy city municipal wastewater treatment plant and assessment of its agricultural application
Mohammad Aqanaghad, Amir Sheikhmohammadi, Esrafil Asgari, Hamidreza Tajfar,
Volume 18, Issue 3 (12-2025)
Abstract
Background and Objective: This study aimed to assess the chemical and microbial quality of sludge generated at the Khoy wastewater treatment plant using an SBR process, and to compare the results with established agricultural standards.
Materials and Methods: In this study, monthly sludge samples were collected and analyzed using standard EPA methods, including the 15-tube technique for coliforms, flotation for Ascaris eggs, and acid digestion for heavy metals. Data were analyzed using SPSS v.25 and statistical analyses included Pearson correlation tests.
Results: The analyzed sludge exhibited an acceptable pH (7.14) and a high organic carbon content (27.32%). However, its elevated salinity (9891 µS/m) and low C/N ratio (6.38) indicated biological instability and limitations for direct agricultural application. The concentrations of heavy metals—including arsenic (10.27 mg/kg), copper (134.86 mg/kg), and zinc (530.93 mg/kg)— exceeded Iran’s national standards. Heat-map analysis confirmed a significant correlation between salinity, and the levels of chloride (Cl-), and sulfate (SO42-). Despite its nutritional value, the sludge is not recommended for direct agricultural use without prior treatments such as stabilization, salinity reduction, and pathogen removal.
Conclusion: Despite the substantial nutrient content of the sludge, including nitrogen, phosphorus, and organic carbon, its direct application in agriculture faces serious limitations due to high salinity, an imbalanced C/N ratio, severe microbial contamination (e.g., nematode eggs), and the exceedance of permissible levels for several heavy metals. Safe utilization of this sludge requires corrective treatments such as stabilization, disinfection, desalination, and regular monitoring of heavy metal concentrations.

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