Iranian Journal of

Background and Objective: Environmental pollution with heavy metals and consequently their entry into food chains leads to irreparable damage to human health. The aim of this study was to determine the concentration of heavy metals including copper, zinc, lead and cadmium in blood and milk of grazing livestock around Zinc industry in Zanjan province (VSIPZ).
Materials and Methods: A total of 10 samples of grazing blood and milk were taken in each of the four geographical directions of the desired location. Also, in order to compare the current situation in the study area with the non-polluted areas, the control area (Qarah Poshtlu area of Zanjan) was considered. Dry ash method was used to digest organic matter.
Results: The results showed that the concentration of copper in the blood of cows and sheeps and the concentration of lead in the blood of cows in the west of VSIPZ was higher than the control group (p <0.05). There was no significant difference between the study areas and the control in terms of zinc and cadmium concentration in blood samples. Copper concentrations in cows and sheeps milk were lower than the control group in the southern and eastern regions of the VSIPZ, respectively (p <0.05). Zinc and lead concentrations in sheeps’ milk were higher than the control in the south and west of the VSIPZ, respectively (p <0.05).
Conclusion: In general, the results implied that the accumulation of lead in sheeps’ milk in the west of VSIPZ is more than maximum allowable concentration and can endanger the health of consumers.

Background and Objective: Dolochar is the residual ash from the production of sponge iron in the process of direct reduction of iron ore by the coal-based method. In Iran, this waste is transported to the nearest landfill. However, these methods are a major environmental concern due to the fineness of the waste and the presence of heavy metals in its composition. The aim of the present study is to investigate the methods of reusing dolochar in order to solve the environmental problem and further use it as auxiliary materials in applications such as road construction and wastewater treatment.
Materials and Methods: In depth investigation of the word “Dolochar” in Science Direct, SID, and MagIran databases showed that there is no long history of reusing it. Only 14 English articles were found, all of which were used in research; Therefore, the present article deals with the issue of reusing Dolochar in Iran for the first time.
Results: By reviewing previous studies, reuse of Dolochar has been classified into five sections. Dolochar use in wastewater treatment (removal of copper, chromium, paint, phosphate, nitrate, surfactant), removal of chromium from mine effluent (more than 94%), as a synthesis gas, as a filter medium (three times better than sand filters) and it is also used in construction and road construction (alternatives to aggregates).
Conclusion: The high capacity of Dolochar in waste absorption and wastewater treatment shows that it is necessary to reuse it in Iran instead of burying or leaving it in the environment.

Background and Objective: It is important to determine the quality of the compost to use compost properly. The aim of this study was to determine the effect of mixing ratio of bulking agent on stability and maturity indices in poultry waste compost.
Materials and Methods: Two piles of sawdust mixture with poultry wastes and volume ratios of 1:1 (W1) and 2:1 (W2) were prepared by Windrow method and a pile containing poultry manure was used as control (W0). In order to determine the stability and maturity indices in compost, the most important physicochemical and biological parameters were studied.
Results: The thermophilic phase lasted about 7 weeks for W1 and about 4 weeks for W2. The initial C/N ratios in the W0, W1 and W2 were 27.10, 31.40 and 56.24, respectively, which eventually reached less than 20. The reduction of organic matter in the three piles was 8.30%, 62.59% and 85.53%, respectively. The thermophilic phase caused a sharp decrease in the population of indicator and pathogenic microorganisms in all piles. The highest dehydrogenase activity in W1 pile was 2.95 mgTPF/gDW.h and by decreasing temperature until the last day, its value decreased to 0.29 mgTPF/gDW.h.
Conclusion: The best ratio for mixing sawdust with poultry manure was 1:1 (v:v). Microbial and enzymatic activities are useful parameters for monitoring poultry composting process and determining the rate of compost stability, and the use of this compost in agriculture will improve soil quality.
 

Background and Objective: Nowadays, individuals spend a lot of time indoors; thus they are exposed to hazardous compounds including polycyclic aromatic hydrocarbons (PAHs) with teratogen, mutagen, and carcinogen potential. Therefore, this study was conducted to detect, and determine the content and source apportionment of PAHs in office building dust samples of Isfahan metropolis in 2023.
Materials and Methods: In this descriptive cross-sectional study, 84 indoor dust samples were collected from 28 sampling sites. After extraction of analytes, the gas chromatography/mass spectrometry (GC–MS) method was used to determine PAHs content in the samples. Molecular diagnostic ratios (MDRs) were used to determine the origin of PAH compounds. Furthermore, all statistical analyses were performed by SPSS software.
Results: The results showed that 16 priority PAHs were detected in the office building dust samples with the minimum, maximum, and mean values (µg/kg) of 4575, 16589, and 9838. Moreover, based on the results obtained, the mean contents of NAPH, FLU, PHE, FULA, PYR, BaA, CHR, BbF, BkF, BaP, DahA, BghiP, and IcdP species were higher than the maximum permissible concentration (MPC) established by Iran DOE. The results of the MDRs method indicated that although PAHs originated from both pyrogenic and petrogenic sources, the pyrogenic sources had the main role in the pollution of office building dusts with PAHs.
Conclusion: Due to risks arising from exposure to PAHs, detection, determination of contents, source identification, and especially health risk assessment of PAHs in indoor dust of other closed places such as commercial, educational, and recreational buildings as well as households is recommended.
 

Background and Objective: The health and safety of the employees of any industry is one of the most important issues to prevent the occurrence of accidents. This study aimed to identify and assess related risks in a battery-manufacturing industry using FMEA method and estimate the ratio of the cost of accidents to prevention.
Materials and Methods: In this descriptive and analytical study, the production activities of the industry were first identified. Then the work process, employee duties, and Potential risks were determined by the HAZID method. Evaluation and prioritization of risks were done using FMEA method. Risks whose RPN was higher than 145 were determined as important risks and the ratio of incident cost to accident prevention was calculated.
Results: In 62 active units of this industry, 716 risks were identified and prioritized, 16 of which (2.23%) had RPN above 145 with the highest priority. The financial pulp unit with falling and fire hazards and the assembly unit with the risk of fumes and lead dust leakage with RPN 245 were among the most dangerous units and hazards identified in the industry. In all units except one unit, the ratio of the cost of accidents to prevention varied from 1.2 to 25.
Conclusion: The results showed that it is necessary to consider the correction of the important risks by the industry officials, according to the set priorities so that potential accidents caused by these risks are minimized. This prioritization can play an effective role in optimal risk management and reduce related costs.
 

Background and Objective: The development of the automobile industry has caused various pollutants to enter the environment, one of which is fluoride. Therefore, this study aims to improve the fluoride removal from wastewater pre-paint units of the automotive industry to achieve discharge standards to surface waters.
Materials and Methods: The study is descriptive and on an applied scale, which has been carried out to compare the efficiency of the chemical coagulation process using lime and alum, as well as the electrocoagulation process using aluminum anodes in the presence of lime to remove fluoride.
Results: The results of real wastewater characteristics showed that the pH of wastewater is in the range of 6.1 to 6.3, and its fluoride concentration is in the range of 45 to 55 mg/L. The results of the experiments show that in the most optimal possible state in the chemical coagulation process, it is possible to achieve fluoride removal efficiency in the range of 76 to 81 percent. However, the removal efficiency in the electrocoagulation process using an aluminum anode at a concentration of 5 mol/L of calcium ions, and current density of 20 A/m² after reaction time of min 20 to 99% can also be achieved.
Conclusion: Considering the high fluoride removal rate (more than 99%) in the electrocoagulation process in the presence of calcium ions, this process can be introduced as an efficient technology for fluoride removal.
 

Background and Objective: Given the concern about the presence of microplastics in the air and settled dust, and the lack of a standard approach for their detection, it is necessary to investigate the methods and techniques used to study this type of pollution in Iran. Therefore, this study aimed to systematically review the methods and techniques used for sampling, quantification, and characterization of microplastics in the air and settled dust in indoor and outdoor environments in Iran.
Materials and Methods: In this systematic review, the keywords Microplastic*, Air*, Atmosphere*, Dust, Indoor, Outdoor, Iran, and their corresponding Persian equivalents were searched until Dec 1, 2023, in Scopus, PubMed, Web of Science, Google Scholar, Magiran, and SID databases. Obtained articles from the databases were analyzed in order to find the eligible ones.
Results: Overall, 175 articles were found in the initial search, and after removing the duplicates and nonrelevant, 13 eligible articles were included in the study. In most of the studies, the samples were digested with H₂O₂, and the microplastics were mainly analyzed using a variety of microscopes and µRaman spectroscopy. The abundance of microplastics in the indoor environment was much higher than in the outdoor environment.
Conclusion: The results of this study showed that there is the required equipment for the sampling and analysis of microplastics in air and settled dust in Iran, and these pollutants have been detected in both indoor and outdoor environments.
 

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.