فصلنامه سلامت و محیط زیست
سال دوازدهم شماره 2 (پیاپی 44، تابستان 1398)

Research has shown that assessing the toxicity and ecological risk of various types of pollutants, including heavy metals, using specific indicators, is indispensable in the ecological risk assessment of the ecosystem. Accordingly, the aim of this study was the assessment of the ecological effect of heavy metals presence (Pb, Zn, Cu, Cd and, As) in Anzali wetland using Heavy Metals Pollution Index (HPI). 43 water samples were collected from the eastern, western and central parts of Anzali wetland. The samples were transferred to the laboratory, and the preparation steps were carried out using the ASTM method. Concentration of the elements was determined by Inductively Coupled Plasma -Atomic Emission Spectroscopy (ICP-AES). According to the concentration of heavy metals in the water samples, the index (HPI) was calculated. The results of the HPI index were classified into three classes: low risk (<15), moderate (15-30), and high risk (> 30). The numerical value of the HPI index was 3.59-23.3 with an average of 27.97, indicating the average level of heavy metals pollution in Anzali wetland. Indicator (HPI) in the eastern part of Anzali wetland and ​​the Pirbazar area showed a severe contamination and ecological hazard of the heavy metals and in the Abkenar region showed an acceptable ecological status. Although the average of HPI in the whole Anzali wetland was modest, but at some stations, especially in the east of the wetland, the HPI indicates the occurrence of ecological hazards in the wetland in the event of uncontrolled entry of pollutants in future. Therefore, monitoring the sources of these pollutants entering to the wetland and controlling the ecological risks is necessary.

Humans are always exposed to ionizing radiation that could potentially have harmful effects. The aim of this study was to evaluate the background gamma dose rate, the estimated annual effective dose, and the excess cancer risk assessment in Dargaz. This study was a cross sectional study which was conducted in January- March and July – September 2016. In this study, 5 stations (4 in the main geographical directions and 1 in the center city) were selected based on the map of the city to determine the dose rate of background gamma radiation in outdoor areas. A dosimeter was used (Geiger Müller detector STEP OD-02 with sensitivity of 0-2000 mSv/h) to measure gamma rays. The device was designed to monitore X-rays, gamma rays and beta rays. The results showed that the maximum and minimum mean values of background gamma dose rate were 147±12 nSv/h and 113±11 nSv/h in the center and west-direction of the city, respectively. The annual effective dose for Dargaz residents in outdoor was determined to be 0/15 mSv/yr, and the amount of excess lifetime cancer risk was estimated as 0.6×10-3. The results indicated that there are significant differences between the rates dose in the center and other parts of the city (p≤0.05).

Heavy metals enter to water resources through various ways, causing dangers such as illness, cancer, and, in general, a disorder in the body of living organisms. Mullet (Liza aurata) is highly consumed by the people living in Guilan province, Iran. Therefore, the amount of heavy metals included copper, zinc, and nickel was investigated in the muscle tissue of mullet. A total number of 11 mullet were obtained from Bandar Anzali.  After a preparation step, the fish samples were digested using chemical digestion, and the amounts of heavy metals were determined by atomic absorption. The average concentration of copper, zinc, and nickel in muscle tissue was 10.07±0.93, 28.39 ±3.99, and 4.01 ± 0.55 μg/g dry weight, respectively. The concentrations of the studied metals were lower than the FAO, WHO, FDA, NHMRC and UKMAFF international standards, except for the nickel. The daily absorption rates of the studied metals (EDI) for children and adults were lower than the reference dose set by the EPA and the TI provided by the FAO / WHO Organization. The risk potential (THQ) of seven days, three days and one day consumption per week of Golden grey mullet for both adults and children were found less than 1. The hazard index (HI) of 7 days a week consumption of mullet for children was greater than 1. According to the results of the present study, the consumption of this fish has a harmful effect on consumer health in children age group.

Since mobile resources are the most important sources of air pollution in the metropolis of Rasht and due to the importance of air pollution in wet weather condition in Rasht, this research was carried out in a specific area to determine the pattern governing the change in the monthly emissions of pollutants on a small scale, using the results obtained from that area. In this study, the amount of air pollutants was estimated on a small scale by continuous monitoring of traffic throughout the year (four days per month and six hours per day) and using MOVES software. The maximum annual average emissions of CO and NOx in the study area were 15.76 (between Gas and Razi squares) and 2 (between Imam Hossein Square and Nirou Daryaee square) g/(m.hr), respectively. In addition, the results showed that the average monthly emission of NOX throughout the year in each of the sections was constant and the average monthly emission of CO in the first half and the second half of the year was constant, and its value in the first half was higher than that in the second half. Hourly distribution of CO emission in different months was affected by events and, in general, the pattern of people's life styles. But the hourly distribution for NOX was roughly constant throughout the year. Also, according to the results, with a single measurement (for CO) and twice measurement (for NOX) of traffic instead of monthly measurements, the pollutant emission estimation in other parts of the city was possible with an acceptable accuracy. Because the generalization of the method used in this study to estimate the emission of pollutants in all roads of the city is not reasonable and cost-effective.

Medical waste is among the environmental problems. Failure to manage these wastes leads to the prevalence of various diseases. This study aimed to rank the educational hospitals of SBUMS by assessing medical waste reduction. First, a review of past national and international studies was performed and accordingly, 12 criteria and 30 sub-criteria for reduction of medical waste production were selected. After developing a questionnaire based on such criteria, data was collected from six SBUMS hospitals. Then, TOPSIS and VIKOR techniques in MATLAB were used as ranking methods of hospitals. The combined results of TOPSIS and VIKOR methods using weighted average indicated that Hospital (C), Hospitals (B) and (A) were respectively ranked first, second and third in terms of waste management. Moreover, the effective measures to reduce the amount of waste production and to improve the waste management system include human resource, management support, proper management of supplies, proper model of service delivery, quality of supplies and equipment, and waste sorting at source. A combined method consisting of TOPSIS and VIKOR for evaluation of ranking of hospitals in terms of waste management can be a helpful tool in planning waste management, and can provide a basis for improving measures and promoting programs and activities.

Human adenoviruses transmitted from contaminated water are one of the major pathogens that has been introduced as one of the most important new qualitative water indicators due to their resistance against the purification processes. The main objective of this study was to evaluate efficiency of human adenovirus removal in different units of Isfahan Water Treatment Plant. Sampling was conducted from 5 points of a water treatment plant including raw water, clarifier, ozonation, filtration, and treated water for one year. Virosorb 1MDS electropositive cartridge filter was used for the concentration of water samples. To test the adenovirus antigens, enzyme-linked immunosorbent assay (ELISA) was employed. Real-time PCR and PCR were also employed for quantitative identification and genotyping, respectively. Moreover, total and fecal coliform and physicochemical parameters of the samples were measured. Out of the 60 samples examined, 12 (20%) samples were diagnosed with ELISA and 16 (26.67%) with molecular method. The highest number of adenoviruses detected in autumn was 7 (12%) in raw water influent, 6 (10%) in clarifier, and 3 (5%) samples in ozonation. The high frequency of adenovirus detection was in autumn (50%) and the lowest was in spring (12.5%). Furthermore, it was found that the total coliform in raw water influent was between 102-103 CFU/mL. The results showed that the removal efficiency of adenovirus in filtration and disinfection units of the treatment plant was high and the filtration unit in the plant was an effective unit for the virus removal.

Heavy metals fixation in-situ by using inorganic amendments is a method for immobilization of polluted soils. The goal of this research was to determine efficiency of five amendments for heavy metals fixation of waste-water-irrigated soils around Tabriz city. Cadmium, Pb, Cu, Ni, and Zn- containing solutions were added to 0.5 gram of five amendments including calcite, hematite, zeolite, illite, and bentonite. 10 soil samples from around of Tabriz city were taken. After shaking the samples, the concentrations of the five elements were determined in the filtered solution by using atomic absorption instrument. Retention capacity percentages of these elements were calculated, and the best amendments were determined by using Dunkan method. There were differences of heavy metals retention between amendments. Calcite had the highest retention of Cd (91%), Ni (78%), and Zn (94.7%); hematite had the highest Cu (90.5%) and Pb (94.3%); and illite showed the lowest retention of the 5 elements. Calcite, zeolite, bentonite, and hematite had significant higher retention capacities of Cd, Ni, and Zn in compared to 10 the soil samples. Among the studied amendments, retention capacities of calcite and hematite for the five elements were higher than the remaining ones for addition to the soil. These two amendments can cause low uptake and low accumulation of the elements in agricultural crops in polluted soils.

Wastewater from pharmaceutical industry has high chemical oxygen demand as a result of the presence of organic drugs and antibiotics. In order to meet the environmental requirements, several treatment methods like chemical and electrochemical methods have been widely applied due to their high ability to remove organic compounds from pharmaceutical wastewater. Therefore, the present study aimed to evaluate the efficiency of chemical coagulation/Electro-Fenton treatment method to degrade the organic matter-containing pharmaceutical industry wastewater. The experimental tests were carried out using batch mode. The chemical coagulation process was evaluated as a function of aluminum chloride concentration (25-300 mg/L) and pH (3-10). The effluent from chemical coagulation process was transferred to Electro-Fenton reactor. Effects of H2O2 concentration (100-4000 mg/L), reaction time (up to 120 min), voltage (10-30 V), and pH (3-10) were evaluated. The removal efficiency was determined in term of COD removal. The results showed that the highest removal of COD in the chemical coagulation was 49% (coagulant dose of 200 mg/L, and pH of 7). In addition, the Electro-Fenton process could be eliminating of 93.5% of COD at the optimum conditions concentration (100 mg/L H2O2, voltage of 20, pH of 3, and contact time of 30 min). According to the results, it can be concluded that the combination of chemical and electrochemical processes was found to be effective methods for treatment of pharmaceutical wastewater in comparison to the application of each process separately. To reach to the maximum removal efficiency, the environmental parameters should be carefully controlled at their optimum values in each single process.

 Bioremediation of contaminants by living microorganisms is a favorable method for elimination or degradation of pollutants to less harmful substances. In the recent decades, cell immobilization technique has been applied to improve biodegradation efficiency and also overcome to free cells disadvantages. The purpose of this review article is to investigate the application of cell immobilization technology with emphsize on polymeric matrices in the aromatic pollutants removal in laboratory scale (shake flask and bioreactor). Also, the performance of free and immobilized cells has been compared in various environmental conditions.  In this survey 401, 78, 49, 1450, 0 and 0 relevant articles were found on Scopus, Web of Science, PubMed, Google scholar, SID and Magiran databases, respectively by using keywords such as “Cell immobilization”, “Biodegradation” and “Aromatic. Out of 1978 articles, 1167 articles were excluded from the study. Finally, 811 articles were further reviewed.  According to the previous studies, removal of contaminants by immobilized cells using appropriate matrices is higher than freely suspended cell systems. Also, among the cell immobilization systems, cell entrapment in the polymeric carriers is the most widely used method for the bioremediation of aromatic contaminants.  Regarding the superiority of immobilized cells in comparison with free cells specially in harsh environments, the reuse of immobilized cells and their application in bioreactors as well as their scale up potential, development and application of these methods can be considered by researchers for wastewater treatment in our country.

The activities of various industries produce a wide range of pollutants and toxic compounds. One of these compounds is the catechol, a cyclic organic compound with high toxicity and resistant to degradation. Therefore, the purpose of this study was to investigate efficiency of powder activated carbon magnetized with Fe3O4 nanoparticles in the removal of catechol from aqueous solutions by response surface methodology. The co-precipitation method was used to synthesize magnetic powder activated carbon and its properties were analyzed by SEM and XRD analysis. Then, the effect of the parameters such as pH, contact time, absorbent dose, initial concentration of catechol and temperature on the efficiency of adsorption process were investigated using a response surface methodology (Box–Behnken). The residual concentration of catechol was measured by HPLC at 275 nm. The results showed that the maximum efficiency of the adsorption process was obtained at concentration of 20 mg/L, pH=3, contact time 90 minutes, at 25 °C and absorbent dose of 1.5 g/L. The study of isotherm and kinetics showed that the experimental data of the catechol adsorption process correlated with the Langmuir and pseudo-second order models, respectively. Thermodynamic study of the reaction also expresses the Exothermic and Spontaneous process. The results showed that the adsorption process using powder activated carbon magnetized with Fe3O4 nanoparticles at acidic pH had better efficiency. As a result, the studied process as an effective, rapid and inexpensive method for removal of catechol from aqueous solutions is proposed. Due to its short reaction time, it is economically affordable process.

Nutrient-rich effluents (mainly nitrogen and phosphorus) may lead to algae blooms and many harmful effects in aquatic environments. Micro-algae have been more effective among the various methods used for the removing of nutrients from wastewater. Microalgae Chlorella vulgaris has specific characteristics such as rapid growth, resistant to systems manipulation, simple and inexpensive production technology, as well as the rapid uptake of nutrients such as phosphate and nitrate. In the present study, two concentrations of chlorella vulgaris microalgae (13 and 26 million cells/mL) were injected into dairy effluent, diluted using distilled water by 25, 50 and 75%, and the amount of nutrient removal and microalgae growth were examined during the growth period. Results indicated that different concentrations of algae at various percentages of dilution (25, 50, 75%) had a significant effect on the removal of nutrients and algal growth (p<0.05). The absorption of nutrients (nitrate, phosphate and ammonia) were 57.01, 51.84 and 43.15 percent respectively that containing lower density of initial algae compared to the treatments of 2nd group (29.15, 51.84 and 43.15 percent) with higher algae concentration. In both algal concentrations, the highest percentage of phosphate and ammonia adsorption were in dilution of 25% effluent and the highest percentage of nitrate adsorption were in the first group with 50% dilution and in the second group with 75% dilution. The more percentage of nutrients (nitrate, phosphate, ammonia) was eliminated compared to the second group (26 million cells / mL) when the microalgae concentration (group I) was 13 million cells / mL. Absorption of nutrients was decreased by increasing the concentration of microalgae. Regarding to the percentage of nitrate adsorption, the higher absorbance in the dilution was occurred at the highest concentration of algae.

Environmental burden of disease (EBD) studies are one of the most important needs for determining the current situation, increasing the effectiveness of health policies and programs and prioritizing environmental health interventions. This review article was evaluated the status of the EBD in Iran based on the results of the latest Global Burden of Disease (GBD) Study, other international studies and national estimates in the country. In this study, the researches on the EBD in Iran were identified by searching in the international and national scientific databases and the search results were studied and analyzed. The review of the EBD studies showed that based on the results of the GBD study, the share of environmental risk factors in the total burden of diseases in the country in 2017 according to the disability-adjusted life years (DALYs) and deaths were about 8 and 13%, respectively. According to the results of the GBD study, the contributions of environmental risk factors in the attributable DALYs in the country in 2017 (a total value of 1,648,329) were as follows: ambient air PM2.5 for 45.0%, occupational risk factors for 25.1%, exposure to lead for 19.4%, unsafe water source for 5.0%, tropospheric ozone for 1.7%, lack of access to handwashing facility for 1.5%, unsafe sanitation for 1.4%, residential radon for 0.6%, and household air pollution from solid fuels for 0.3%. The total DALY rate and death rate attributable to solar ultraviolet radiation in Iran in 2000 were estimated to be 46.2 and 0.7, respectively. The DALY and the DALY rate attributable to elevated levels of fluoride in drinking water due to dental fluorosis in the country in 2017 were 3,443 and 4.14, respectively. The evaluation of the effect of water fluoridation as an environmental protective factor showed that the intervention by reducing the risk of dental caries could fall the DALY and DALY rates in the country by 14,971 and 18.73, respectively. In the period of 2005-2017, the DALY rate (per 100,000 people) attributable to ambient air PM2.5, tropospheric ozone, residential radon, and occupational risk factors rose that the result increases the importance of the preventive measures and controls of these risk factors. There was a considerable difference in the burden of disease attributed to each risk factor in various international studies as well as between national and international studies. The results of national studies on the burden of diseases attributable to environmental risk factors are considered to be more reliable and practical due to the application of more detailed data and conducting subnational evaluations; therefore, the strengthening and continuing these studies at the national and sub-national levels with regard to priorities, needs, and spatiotemporal trends using domestic reliable data and information are necessary and strictly recommended.