فصلنامه سلامت و محیط زیست
سال سیزدهم شماره 2 (پیاپی 48، تابستان 1399)

In this study, we aimed to assess Iran’s position and trends for environmental health status among the countries of “Iran’s perspective document in 1404” according to the indicators used in Environmental Performance Index (EPI) report in 2018.

The score of indicators in environmental health area; air quality (including household solid fuels, exposure to PM2.5, and PM2.5 exceedance), water and sanitation (including drinking water and sanitation) and heavy metals (including lead) were extracted for all studied countries as well as for the last and baseline (generally ten years prior to last report) years from EPI 2018 database. According to EPI scores, the performance of the studied countries in each indicator was ranked. The percent change in the score of each indicator from baseline to current year was calculated and compared with the mean percent change for all studied countries.

Iran ranked 7th regarding air quality in 2016. Also, it ranked 6th, 8th, and 9th in terms of household solid fuels, exposure to PM2.5, and PM2.5 exceedance, respectively. The EPI score for Iran regarding water and sanitation was 54.4 in 2005 and 58.74 in 2016 (percent change=7.98%). Iran ranked 21st in 2005 regarding lead exposure index. Although this index showed a growth of 100% in 2016, which is very desirable compared to the average growth of all countries (34.47%), but only leads to one step up in the ranking of Iran and was ranked 20th in comparison with other countries.

Totally, according to EPI 2018, Iran ranked 6th in the field of environmental health issues among 23 countries of “Iran’s perspective document in 1404”. However, there is uncertainty in the accuracy of the EPI raw data used for calculating index scores. Hence, caution should be exercised in their interpretation.

During the last few years, air pollution and increasing levels of particulate matters (PMs) have become major public health issues in the megacity of Tehran. The high cost of constructing and maintaining air pollution monitoring stations has made it difficult to achieve adequate spatial-temporal coverage of PM data over various regions. In this regard, the use of remote sensing data such as aerosol optical depth (AOD) can be a simple and cost-effective way to overcome the problem.

Due to the weakness of univariate linear relationship of PM10-AOD under normal conditions, this relationship has been studied for the time periods of dust storm occurrence during 2007-2010 in Tehran. Satellite product with spatial resolution of 3 and 10 km obtained from MODIS sensor were used to fit the models.

Results showed that the best performance of univariate model was achieved for 5 km radius of AOD extraction and daily mean of PM10 concentrations (r = 0.55). Moreover, the use of meteorological auxiliary variables and the development of multivariate linear regression model have improved the performance of the model (r = 0.64). The final model also exhibited accurate capability for prediction of high PM10 concentrations during dusty days.

Overall, the obtained univariate linear relationships of PM10-AOD was stronger during dusty episodes than those of normal conditions, suggest a higher correlation between AOD and PM10 from dust activities as compared with PM10 originating from other sources. Furthermore, the final developed model could be used to predict daily level of PM10 concentrations during dusty episodes.

Since people spend a lot of time indoors, assessment of Sick Building Syndrome (SBS)is the first step to improve working and living conditions in closed environments. This study wasconducted to evaluate the SBS symptoms among staff in Razi Hospital of Chalous, to identify the affecting environmental parameters on these symptoms and to provide solutions to reduce the symptoms of SBS.

This descriptive-analytical study was conductedrandomly among 72 out of 240 hospital’s staff. Questionnaire MM040EA was used to collect demographic data, SBS symptoms and affecting environmental factors. Statistical analysis was carried out using Pearson’s Chi-squared test and Fisherchr('39')s exact test in Excel software.

60% of people showed moderate to severe SBS symptoms. Fatigue, headache, and sneezing were the most common symptoms among staff, with 85%, 75%, and 63%, respectively. Significant correlation was observed between SBS symptoms and room temperature fluctuations (p <0.001), low ambient temperature (p = 0.037), unpleasant odor (p = 0.043) and gender (p = 0.011) with significance level of α=0.05.

Investigating the influence of work environmental related factors on the general symptoms of SBS as well as on fatigue, headache and sneezing symptoms showed room temperature fluctuation and unpleasant odor as the most important driving factors. These symptoms were mainly due to the improper air conditioning system operation at the hospital to control the temperature. Therefore, it is expected that the prevalence of SBS among staff can be reduced significantly by improving the ventilation system performance, especially in winter.

The purpose of this cross-sectional study is to evaluate the microbial contamination of food-handlerschr('39') hands and food contact surfaces in food preparation and distribution centers.

This study was performed in 2019 in Fardis city of Alborz province. In this study, 100 samples of food contact surfaces and 48 samples of staff hands were collected from three traditional bakery units, pastry centers and snack shops and the microbial load was determined using a luminometer device. The samples were then analyzed for the presence of coliforms, Escherichia coli and Staphylococcus aureus bacteria.

Among the samples studied, 62 samples (62%) of contact surfaces and 27 samples (56.25%) of food-handlerschr('39') hands had microbial load more than 30 RLU.  According to the results, the main cause of microbial contamination of equipments were 44.40% of Coliform bacteria and 11.10% of Staphylococcus aureus on the equipment of confectionery centers,  10% of Escherichia coli, 20% of coliforms and 20% of Staphylococcus aureus were detected on food tools and 2.30% of Escherichia coli, 14% of coliforms and 14% of Staphylococcus aureus –on the tools of traditional bakeries.Moreover coliform bacteria was noticed onconfectionary-handlerschr('39') hands and all three types of bacteria were also found on the hands of bakers.

The results showed that the cleanliness of food contact surfaces and the personnel hands hygiene was in poor condition which may pose serious threat to public health. Therefore, adequate personal hygiene practices, food safety and inspections should be implemented to protect the health of society.

Silver is a toxic heavy metal that is used in various industries and has adverse effects on both human health and the environment. In this respect its determination with sensitive and economic analytical methods is of great importance.

In this research, a novel ion selective electrode based on perphenazine as an ionophore was developed for determination of Ag+. The optimum composition that showed the highest sensitivity was constructed by mixing 9% ionophore, 2% NaTPB as ionic additive, 59% DOP as the plasticizer and 30% PVC.

The designed sensor showed a linear response over the concentration range of 1×10-6-1×10-2 M with the slope of 60.3 mV/Decade. The detection limit of the electrode was obtained 9×10-7 M. The response time and lifetime of the proposed sensor were 5 seconds and 10 weeks, respectively. The selectivity of electrode was evaluated by matched potential method and no serious interference was observed.

In the end, the sensor applicability in determination of Ag+ in three waste water specimens as real samples was evaluated and the good agreement between the results of sensor and the results of flame atomic absorption spectroscopy showed the designed electrode has enough accuracy and it can be used for determination of Ag (I) in the aqueous environmental samples. In conclusion, finally the performance of the prepared sensor in determining the amount of silver ions in three effluent samples was evaluated as the real samples. The results were in good agreement with those obtained by flame atomic absorption method which indicates that the designed sensor can be successfully employed in the accurate determination of silver (I) in environmental aqueous samples.

Global market growth of reverse osmosis (RO) has led to an increase in annual disposal of membrane wastes. Therefore, evaluation of membrane waste management strategies is important to reduce their adverse environmental impacts. Due to the widespread domestic RO membrane market and their economic considerations, this study aims at investigation the direct recycling methods of RO membranes to extend their life cycles.

Academic search engines and citation databases such Scopus and PubMed was used to retrieve relevant papers. Selected documents were analyzed and compared in three aspects of technical, economic and environmental issues. 

Direct recycling of RO is performed with fouling removal and degradation of polyamide layer (PA) using oxidizing agents like KMnO4 and NaOCl. The degradation rate of the PA layer is controlled by optimizing the oxidant concentration during the oxidation process. Factors such as the type of membrane used, its storage conditions, the operating units’ conditions and the final expected product will determine the required concentration-time values. Strategies to reduce these values are very important from an economic and environmental point of view. Decreasing the concentration of oxidizing agent reduces the chlorinated and halogenated compounds emitted from the oxidizing unit which subsequently lessen their harmful environmental impacts and reduces the energy consumption required for treatment.

 The conversion of RO membranes to porous filters is technically possible by optimizing the conditions. In addition, the proper choice of RO membrane and final product type lead to economic and environmental productivity.

One of the major challenges facing landfill operation is the pollution caused by leachate infiltration beneath the landfill site. Comprehensive leachate management requires knowledge of production rate and factors affecting it Therefore, in this study, HELP software was used to calculate leachate quantity and analyze input data.

After designing a landfill by the existing conditions in Urmia city, the quantity of leachate was calculated using HELP software. Then, in different scenarios, the effects of precipitation, Curve number, and removal of the geomembrane layer on leachate production -were investigated. Finally, the impact of similar layer aggregation on the simulation process was discussed.

According to the results, 7.67% of precipitation is converted to leachate. NO significant correlation was observed between precipitation and leachate production in a short period of time due to the absorption of rain by landfill layers. However, for the long term, as the absorption capacity was reached leachate produced. With increasing the Curve number from 70 to 90, leachate production decreased by 23%. Also, the removal of geomembrane from the final coating increased the amount of leachate by 78.46%. Furthermore, by replacing a 76cm dense clay layer instead of capping geomembrane layer, the same leachate generation rate was observed. Re- running the software after layer aggregation showed a slight difference in leachate estimation compared to the baseline state.

Leachate generation modeling and identifying influential parameters with the aim of HELP software, may be helpful in landfill leachate management prior to its construction.

Surface water is usually highly variable in chemical composition due to contact with different geological formationsand other surface and groundwater resources.  Knowledge on water quality and the impact of human activities are particularly important for sustainable management and planning of water resources. The aim of this study was to investigate the physicochemical and hydrochemical quality of Chehelchai river water in Golestan province.

In this study, 6 sampling stations were selected based on standard criteria including land use type, accessibility and standard distributions along the river in 2018. 10 river water quality parameters including pH, electrical conductivity, total soluble solids, sulfate, chloride, bicarbonate, sodium, potassium, calcium and magnesium - were measured according to standard methods for one year period. Piper, Schuler, Durov, Wilcox and Gibbs diagrams were applied for hydrochemical analysis using RockWorks.17 software.  Statistical analysis was performed using one-way ANOVA.

 Results indicated the abundance of major ions was found in the order of HCO3- > SO42- > Cl- and Ca2+ > Na+ > Mg2+ > K+. The river water type was predominantly determined as calcic bicarbonate. The findings revealed that the water of the study area is acceptable for drinking purpose based on Schuler diagram and also appropriate for agricultural uses considering Wilcox diagram (80% of the samples in class S1-C3 (saline - usable for agriculture)) and the average sodium uptake ratio (0.79).

The presence of dolomite ores, the absence of factories and domestic sewage and adhering to hygiene regulations by the residents, are the main reasons which have increased the quality of Chehelchai river water.

Urban traffic, while affecting human health, causes physiological and biochemical changes in plants. The aim of this study was to investigate the bioaccumulation potential of Pb and Cd and assess air pollution tolerance index for a number of plants grown high traffic areas of Yazd.

This cross-sectional, descriptive-analytical study was performed in both control and high traffic areas of Yazd city by random sampling of trees, shrub and herb species. After transferring the samples to laboratory, relative water content, pH of leaf extract, total chlorophyll and ascorbic acid content (the factors for calculating APTI) in plants were measured using standard methods. Furtheremore, Pb and Cd concentrations were measured to find their relation with APTI index in plants. All statistical analysis, including Kolmogorov–Smirnov test, ANOVA, Duncan test and Pearson correlation coefficient between the studied parameters, were performed in SPSS software version 22.

The highest relative water content (84.73%) and ascorbic acid (5.98 mg/g) were measured in contaminated area for Canna indica and Rosa damascena, respectively. Also, the highest acidity (7.01) and total chlorophyll (1.48 mg/g) in the control area were measured for Verbena hybrida and Ligustrum vulgar, respectively. The highest air pollution tolerance values were recorded in Rosa damascena and Ligustrum vulgar. Moreover, the results obtained showed that APTI index was positively and significantly correlated to Pb, ascorbic acid and relative water content.

According to the classification of air pollution tolerance index, two species of Rosa damascena and Ligustrum vulgar exhibited moderately tolerant to traffic pollutant. Therefore, based on ecological requirements of these two species, they can be used to develop green spaces in high-traffic areas of Yazd.  This study showed that Pb increased physiological response of the studied plants, while the plants did not exhibit a significant physiological response to the Cd element. The results also showed that the relative water content and ascorbic acid were more important in the air pollution tolerance index than other factors.

Hexavalent chromium is reported to be highly toxic, mutagenic and carcinogenic; hence treatment of water and wastewater contaminated with this element by low-cost and environmentally friendly methods is of great importance. Therefore the aim of present study was to evaluate the efficiency of Fe(II) modified bentonite for hexavalent chromium removal from a simulated wastewater.

In this study, Fe(II) modified bentonite was synthesized. Structure and morphology of bentonite were investigated by XRD and SEM techniques. Experiments were carried out as central composite design with three input parameters namely initial hexavalent chromium, pH and adsorbent dosage at 5 levels. Finally, the results were assessed by adsorption isotherm models.

The findings revealed that complete removal efficiency of Cr (VI) achieved at pH of 2, initial hexavalent chromium concentration of 20 mg/L and adsorbent dose of 5 g/L. The adsorption isotherm model found to fit well with Langmuir isotherm model and revealed that the monolayer adsorption of hexavalent chromium at adsorbent surface was happened. The equilibrium data better fitted the Langmuir isotherm model suggested a monolayer adsorption nature of the modified bentonite.

  The findings in this study showed the promise of use of Fe(II) modified bentonite for Cr (VI) removal. Moreover, response surface methodology can be used as an effective method to optimize hexavalent chromium removal from wastewaters.

Heavy metal contamination of surface soils has become a serious concern. The aim of this study was to evaluate the potential risk of heavy metal (loid) pollution on human health in the surface soils of Arak industrial areas, the capital of Markazi province in western Iran.

235 surface soil samples were collected from a depth of 0-5 cm. Concentrations of lead, cadmium, nickel, zinc, copper and arsenic were determined by digestion with nitric acid (4 N). The level of soil pollution in the region was measured using geo- accumulation index (Igeo) and enrichment factor (EF). The model proposed by the U.S Environmental Protection Agency (USEPA) was used to assess the health risks of heavy metals.

The Mean concentrations of Pb, Cd, As, Cu, Ni, and Zn were 37.88, 1.17, 151.78, 13.48, 92.98 and 104.04 mg/kg, respectively. The calculated enrichment factor values ​​for soil samples varied from deficiency to significant enrichment. The mean geo-accumulation index (Igeo) for Pb, Cd, Cu, Ni, Zn and arsenic were 0.37, 1.59, -2.53, -0.48, -0.63 and 2.9, respectively. The results of the health risk assessment showed that hazard quotient (HQ) for children and adults through the ingestion route was higher than dermal contact and inhalation pathway. The Hazard index values for all studied metals were lower than the safe level of 1 except for As. Arsenic showed the highest risk of carcinogenicity (CR) for children (2.37 x 10-4) through ingestion.

The carcinogenic risk (CR) of As in children and adults is higher than the safe limit of 1 × 10-4, which indicates an unacceptable risk.

Improper landfilling of drilling waste has adverse effects on the environment and human health. This study aims to select suitable landfills for oil and gas drilling waste on Qeshm Island using GIS and AHP.

In this study, a weighted map was prepared based on each criterion affecting the site location. In the next step, each of the prepared layers was ranked. Higher rating indicated the importance of each layer while lower values corresponded to their insignificane.

The reasults of this study showed that the distance from population centers (weight 0.222), communication network (roads) (weight 0.169) and surface waters (weight 0.142) are important parameters for landfill siting. The combination of ranked maps and the weights obtained from AHP, divided the landfill area to “completely suitable”, “suitable”, “relatively suitable”, “relatively unsuitable” and “unsuitable”.

Priorities identified in “completely suitable” areas can be the basis for decision-making, and appropriate locations can be on the agenda as next priorities.