فصلنامه سلامت و محیط زیست
سال سیزدهم شماره 4 (پیاپی 50، زمستان 1399)

Improper treatment of PAHs in oily drilling cuttings cause adverse effects on the environment. The present study aimed to investigate the efficiency of two bioremediation and fixation methods for PAHs removal from oily drilling cuttings. The efficiency of the two mentioned methods were analyzed and subsequentelythe more effective one was selected using environmental protection approach.

The sampling of oily drilling cuttings at the beginning and end of the treating process was performed for the studied methods, according to standard protocols. The amounts of PAHs, are determined by Soxhlet apparatus and gas chromatography-mass spectrometery.

The results showed that the removal efficiency of PAHs from oily drilling cuttings was 97% (440.3 mg/kg) for bioremediation and 78% (354.7 mg/kg) for the fixation method, respectively. The findings showed that the bioremediation method provides the standard requirements for the discharge of PAHs to the environment.

Bioremediation is more effective than the fixation method for removing PAHs compounds and exhibits higher environmental protection performance.

The bibliometric analysis is the most effective way to study the scientific output and trend of research. The purpose of this study is to analyze the scientific output of the Institute of Environmental Research (IER) at Tehran University of Medical Sciences using bibliometric technique.

All related IER articles that have been indexed in Scopus and WoK were retrieved from the beginning of 2009 till November 23, 2019. The bibliometric data were extracted and analyzed using R software.

The document production follows an increasing exponential trend with a rate of 10% per year. 807 documents were retrieved with an average citations of 19.26 per each document. The documents per author and authors per document were obtained 0.196 and 5.1, respectively. The highest citations to documents was in 2017 (35.5 citations). The most frequent keywords were found “Adsorption”, “Drinking water”, “Air pollution”, “Particulate matter”, “Risk assessment” and “Response surface methodology”. Thus, engineering-based studies are more prominent in the published studies. Health-based studies, including risk assessment studies, accounted for the most area of research. The largest numbers of international research collaboration were recorded with the United States, Switzerland, Canada and India. While, in the national scale, Shahid Beheshti University of Medical Sciences’ collaboration was prominent.

It is still necessary to promote the level of the IER’s international collaborations to raise its regional status. In addition, more attention should be paid to health-based topics like risk assessment studies. These studies need to be given higher priority in the action plan of the IER’s centers and research groups.

Monitoring of traffic emissions is a good way to build a safe ecosystem for living organisms. Therefore, the present study was conducted to assess the feasibility of using Achillea wilhelmsii and Cardaria draba located along the suburban roads of Hamadan for Zn, Pb and Ni removal by their aerial and underground organs in 2020.

In this descriptive study, after selecting 3 sampling stations, a total of 126 plant samples and 63 soil samples were collected. In the laboratory, the samples were prepared, and were then digested with acid. Subsequentely, the concentration of each heavy metal was measured by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Moreover, bioconcentration factor (BCF), bioaccumulation factor (BAF), transfer factor (TF) and metal accumulation index (MAI) were also calculated. Statistical analyses of the results were performed using SPSS statistical software.

The mean values of BCF and BAF in both A. wilhelmsii and C. draba for all tested elements were greater than 1. On the other hand, A. wilhelmsii showed TF greater than 1 for zinc while C. draba showed TF greater than 1 for zinc and lead. The highest mean values of MAI in unwashed and washed shoots and roots of A. wilhelmsii were 98.48, 64.87 and 72.38, respectively.

Based on the calculated average values of BCF, BAF and TF of each elements, it can be argued that A. wilhelmsii and C. draba species have the potential of phytoextraction and Phytostabilization of the measured heavy metals and can be used for biomonitoring and bioremediation from soil and air in the heavy metals polluted areas.

 Landfills as municipal solid waste are considered as the source of pollution. The present study aimed to assess the ecological risk of heavy metals in Tehran landfill soil and the adjacent residential area.

 Having consulted with the specialists and considered the waste processing facilities, 12 sampling points were selected and sampled in four seasons. Soil samples were digested using HNO3: HClO4: HCl: HF. The levels of metals were measured using ICP-OES which further applied for the calculation of ecological risk. Kolmogorov-Smirnov, Kruskal-Wallis, and Pearson correlation coefficient analyses were run to determine the significant differences between metals concentrations in various seasons and sampling points. 

 Metal concentration showed to follow theorder: Al > Fe > Mn > Zn > Cr > Pb > Cu >Ni > Co > As > Cd. Kruskal-Wallis results and pairwise comparison showed a statistically significant difference between metal concentrations across sampling points and seasons, especially in rainy seasons. Pearson correlation coefficient displayed a strong relationship between the mean concentrations of Cu - Pb, Cu - Zn, and Pb - Zn with obtained values of 0.932, 0.874, and 0.883, respectively. Cu exhibited the highest contamination factor at the compost and fermentation sites (13.2 and 9.89, respectively). The geo-accumulation index proved the anthropogenic sources of pollution. The potential ecological risk index (ERI) for the sampling sites ranged from 67.3 to 154, with the order of Cd > Cu > Pb > Ni > As > Cr > Zn > Co > Mn. 

 Due to the obtained moderate to severe ecological risk and exceeded background concentrations of heavy metals, it can be concluded that metal changes and soil pollution are both affected by landfill activities.

Air pollution is one of the most important environmental risk factors that exposure to it can cause many acute and chronic effects on human health. Some regions of Iran, especially the western, southern and southeastern provinces of the country, have been affected with dust storm for years. Studies on the frequencies of dusty days in the country show that central pits of Iran and the cities of Zabol and Zahedan have the highest incidence of dusty days. The purpose of this study was to determine the concentration of suspended particles with aerodynamic diameter of 2.5 μm or less (PM2.5) in various seasons and months during 2019 in Zahedan.

In this descriptive-analytical and cross-sectional study samples were typically collected once every 6 days during a 24-hour period as well as on dusty days using an air sampler (PQ200 / BGI) from July 2018 to July 2019.

The results show that the mean concentration of PM2.5 in Zahedan during this study was 36.86 µg/m3. The maximum and minimum PM2.5 daily concentrations in the sampling days were also measured as 130.8 and 4.75 µg/m3, respectively.

In conclusion, 88% of samples contained PM2.5 concentration above the WHO 24-hr air quality guideline level (25 µg/m3), which could be due to the high incidence of summer dust storms. This indicates that particulate matters are a serious health threat to people living in those areas and calls for the implementing measures to tackle the problem.

Transportation sector generates the largest share of greenhouse gas emissions (CO2 and CH4) which causes global warming. “Stop-and-go” driving and congested traffic flow results in a decrease in average car speeds, an increase in traffic incidents, and finally escalates GHGs emissions. Hence, congestion is directly related to carbon emissions. The objective of this study was to estimate the GHGs emissions of urban transportation sector using the congestion index.

The traffic flow in the main street of Hamadan city was continuously monitored in 8 time periods from 8 am to 12 pm in August 2018. Then, a traffic congestion map was prepared. Subsequently the surface area and weight coefficient of each road were obtained based on the traffic assignment model. Finally, the amount of GHGs emissions from transportation sector, CO2 emission per capita, and annual amount of CO2 and CH4 release in each street were calculated and estimated.

Results showed that the total CO2 and CH4 emissions from the transportation sector of Hamadan city are 776000 and 396 ton/year, respectively. Imam Khomeini Highway (29166 ton CO2/year) and Mirzadeh Eshghi Street (24453 ton CO2/year) recorded the highest level of carbon emission due to the highespeed and more width “stop and go” driving conditions.

The conformity of the congestion index with the traffic assignment model can be used to estimate the amount of urban traffic pollution. Finally, because of the high growth rate of CO2 and CH4 and the role of forests in maximizing carbon sequestration, it is imperative to manage and increase green spaces to reduce CO2.

SO2 pollution has become a serious concern. The aim of this study is SO2 removal from JP-4 fuel combustion.

Experiments were performed by thermogravimetric analysis at different temperatures and various SO2 concentration. Kinetic study of non-catalytic gas-solid reaction was performed using mathematical modeling based on random pore model.

The pore size distribution curve was obtained. The structural parameters of the random pore model were measured as r=1.92×10-5, ε0=0.64, S0=1.27×106 and ψ=3.81. Thermogravimetry diagram and conversion-time curves were extracted. Fractional reaction modeling is obtained based on gas reactant.

The obtained kinetic parameters can be used to design flue gas desulfurization systems at low temperatures.

One of the most important factors affecting communities’ health is safe drinking water. The UN general assembly considers “ensure availability and sustainable water and sanitation for all “as one of the 17 goals of SDGs for the 2030 development agenda.  Target 6.1 of SDGs aims to provide universal and equitable access to affordable drinking water and to provide safe drinking water for all households. Target 6.2 calls for an end to defecation in an open environment to ensure that each person has access to the toilet and safe disposal system. In current study, 143 Savadkooh villages with defects in water supply systems and health services were selected to update the indicators and implement sustainable development goals.  

A checklist was designed to extract targets 6.1 and 6.2 based on the Joint Monitoring Program (JMP). Considering 7400 households, margin of error of 5%, confidence limit of 95%, and the most conservative mode for response distribution (50%), the sample size was determined (512 households). Samples were collected randomly from all villages and then analysis was performed by SPSS 19.

In drinking water sector, 84% of people have access to safe services, while only 15% and 1% have access to basic services and unimproved services, respectively. In sanitation sector, 98.8% of people use safe services though only 0.2% utilize limited services. In hygiene sector, 98.8% of people are provided with safe services.

Lack of drinking water safety and failure to improve water resources’ quality are the main problems in the drinking water sector. Lack of access to sewage network, wastewater disposal in the land is the biggest health hazard in the region. This study can provide solutions to improve the health quality of affected community.

Bioremediation and one of its main branches, namely phytoremediation, is one of the most important and basic processes for eliminating pollutants from the environment. Due to the large number of silica factories in Azandarian area of ​​Malayer city and high soil silica pollution in this area, this study was conducted to compare the bioremediation effect of Fusarium oxysporum and Portulace olerace.L phytoremediation on silica uptake.

For this purpose, portulaca oleracea was cultivated in greenhouse conditions and different concentrations of silica and under the treatment of fungi in a completely random statistical design. For this purpose, portulaca oleracea cultivation was carried out under greenhouse conditions, fungal treatment and in different concentrations of silica in a completely randomized manner.

The results showed that the fungus grew easily at high speed at 95% concentration of silica and was able to absorb 84.50% of the silica in the soil and the plant was able to absorb 80% of silica, the highest absorption rate of 69.71% and the highest rate of silica uptake in plant and fungus coexistence is 80% silica and 69.90%. The results showed that the fungus grew easily in the presence of silica with 95% concentration and could absorb 84.50% of silica in the soil. In the presence of 80% silica, the plant demonstrated the highest adsorption rate of 61.71%. The highest rate of silica uptake (69.90%) was reached at the 80% initial concentration of silica under the coexistence activities of plant and fungi.

In conclusion, silica exhibited a positive and significant effect on the physiological traits of Portulaca oleracea and also increased the amount of phenol, flavonoids, and anthocyanins. The coexistence of fungi and plants also increased the mentioned physiological traits in Portulaca oleracea. Also, the coexistence of plants and fungi showed a positive effect on silica adsorption, which can be effective in reducing silica contamination in the region.

Air quality and distribution of trace elements in the Tehran metropolis were evaluated using transplants of the epiphytic lichen Ramalina sinensis.

Thalli of R. sinensis were collected from a non-contaminated area and transplanted in the six urban sites of Tehran for six months. After the end of the exposure period, the content of twelve elements in lichen was determined by ICP-MS method and the obtained data were evalusted using statistical analysis and various indicators.

Based on the results, the order of mean concentration of the trace elements in the R. sinensis lichen samples was determined as: Ca > K > Fe > Mg > Na > Mn > Zn > Pb > Cr > Cu > Ni > Co and the highest amount of bioaccumulation was found for the essential elements. For sevelar elements, significant differences were observed in various sampling sites. Based on the pollution load indexes (PLIs), two sites at Sharif university and Setad Bohran were more polluted than other areas. Exposed-to-control (EC) ratio values for Pb, Zn, Cr, Fe, Mn, Ni, Mg, and Co were also found in the range of 1.25-1.75. Based on the relative accumulation factor (RAF), the accumulation preference of elements by R. sinensis lichen was observed as Na > Cr > Cu > Fe > Mg > Ni > Zn > Mn > Co > Pb > Ca > K, respectively, which represents the significant ability of this species in the accumulation of elements such as Na, Cr, Cu and Fe. PCA and EF analysis indicated that trace elements adsorbed by lichen were mainly sourced from vehicle transportation.

This study demonstrates the application and importance of R. sinensis lichen in biomonitoring of air pollutants elements in urban areas. This approach can justify the suitability, accuracy and cost-effectiveness of lichen compared to other biomonitors for air pollutants and more importantly highlights its capability to the determination of wide levels of air pollution in large scales.

The aim of this study was to investigate the effect of seasonal variation on the diversity of fungal airborne species in the composting process.

Samples were taken based on the 0800 NIOSH method at a height of 1.5 m above the ground during the waste separation, turning of windrow and stabilization of compost. Air samples were collected in two various seasons; summer (108 samples) and winter (108 samples) at the composting plant in Shiraz. The culture media consisted of Sabouraud Dextrose Agar with chloramphenicol for the selective isolation of fungi, which was further incubated at 37 and 45°C. The results were analyzed by a t-test method using MATLAB 2018.

The highest mesophilic fungi density was related to the segregation process of composting. The variation of fungi observed was higher during summer throughout separation and stabilization process (p < 0.05). The predominant species were found to be Aspergillus flavus (4449.8 CFU/m3) (p < 0.05) and Paecilomyces (1850.9 CFU/m3) (p < 0.05), respectively. Furthermore, the highest varieties of fungal species in the turning of windrow mass were observed during winter (p < 0.05) and the predominant species was yeast (420.6 CFU/m3). At all stages of composting, the varieties of thermophilic fungal species were higher during summer with the large number of Aspergillus fumigatus, Mucoral, and Paecilomyces.

The density and diversity of mesophilic fungi during summer was higher than winter. The concentration of Aspergillus, was beyond the guidelines set by the EPA, ACGIH, NIOSH and EU. Thus, the use of self-protection is essential.

Pollutants emitted from industries can endanger human health if they enter the food chain, so environmental monitoring is essential. The aim of this study was to investigate the bioaccumulation of heavy metals including lead, copper and nickel and the level of air pollution tolerance index in Prosopis juliflora and Conocarpus erectus tree species during one-year period (1399-1400) in Mahshahr city.

In order to investigate the bioaccumulation of heavy metals by two species of Prosopis juliflora and Conocarpus erectus, 15 stations were selected separately. After recording the coordinates of each tree (station), 4 leaveas were taken from each tree that accounted for total 60 samples. The samples were then transferred to the laboratory and digested then analyzed using atomic absorption spectrometer. For statistical analysis, K.S test was used to normalize data and independent t-tests were applied to determine the level of significance. The correlation between variables were tested by Pearson correlation. Spatial distribution of heavy metals was performed using Ver.10.4 Arc GIS software.

Conocarpus erectus established the highest adsorption value for metals such as lead (0.1223±0.35 mg/kg), copper (0.2101±0.053 mg/kg) and nickel (0.2023±0.094 mg/kg). No significant correlation was observed between heavy metals. Evaluation of air pollution tolerance showed that Conocarpus erectus (6.53±0.026 mg/kg) was more tolerant than Prosopis juliflora (4.77±0.029 mg/kg). Spatial distribution revealed that heavy metals accumulation in the leaves of trees were more obvious in the southest area of the city.

Conocarpus erectus is more tolerant of air pollution than Prosopis juliflora. Therefore, it can be used in areas with the high levels of pollution. Moreover, the spatial distribution of heavy metals’ bioaccumulation illustrated that the south and southeast parts of the city (due to industry concentration) are more affected by the heavy metals pollution which call for more palnting trees.