فصلنامه سلامت و محیط زیست
سال نهم شماره 2 (پیاپی 32، تابستان 1395)

Milk is a full meal that can provide an appropriate growing environment for different bacteria. Hence, it can be hazardous to human health in unpasteurized conditions. The present study was conducted in order to assess the prevalence and antimicrobial resistance of Staphylococcus aureus in raw and pasteurized milks of Sari City in the summer of 2014.
This cross-sectional study was conducted in the summer of 2014 in the city of Sari. Totally, 160 samples- each 200 mL of raw milk were collected from collection and distribution centers (80 samples) of raw milk, and pasteurized milk from food stores (80 samples). Under aseptic conditions, confirmatory tests were carried out in Chapman and Blood agar media. Antibiogram test was performed for positive samples. Results were analyzed using SPSS (Ver. 19) software through the t-test descriptive statistical analysis.
The results showed that 38.75% of 80 samples of raw milk collected were contaminated by Staphylococcus aureus, while no contamination was observed in pasteurized milk samples. The average number of colony formation of raw milk was estimated to be within 3×104 to 7×104 Cfu/mL. Maximum sensitivity was found against vancomycin, gentamicin, and Co-trimoxazole antibiotics and the maximum resistance was observed against ampicillin, methicillin and cephalotin antibiotics with of 87.5, 25, and 12.5%, respectively.
The raw milk showed the prevalence of Staphylococcus aureus. Therefore, compliance with and control of sanitation at different steps of preparation, supplying and consumption of milk can prevent the human infection with this type of contamination.

Street dust reflects one of the most important indicators of pollution in the urban environment. Most studies carried out in the world on heavy metal pollution are related to cities and metropolitans¡ while less attention has been paid to towns. Masjed-e- Soleiman¡ the most oil-rich town is located in the north eastern part of Khuzestan Province in Iran. This town contains geogenic pollutants such as gas and oil sources¡ oil and gas activities¡ oil and gas combustion¡ industries¡ and heavy traffic¡ which make it important from the viewpoint of environmental impact assessment.
For monitoring and management of pollution¡ 11 samples of street dust were collected and prepared from different stations within the town during the dry season (June 2013). Each sample was analyzed using ICP-OES instrument.
Possible sources of the heavy metals were identified by multivariate analyses such as Principal Component Analysis (PCA) and Cluster Analysis (CA). In addition¡ factors such as the Index of Geo-accumulation (Igeo)¡ Pollution Index (PI)¡ Integration Pollution Index (IPI)¡ and Enrichment Factor (EF) were assessed to determine the degree of heavy metals pollution in street dust of the Masjed-e- Soleiman Town. The results of PCA and CA indicated that the region is mostly affected by oil pollution (both natural and combustion of fossil fuels)¡ traffic¡ and industrial activities (PI revealed high levels of Pb¡ Cd¡ Cu¡ and Zn pollution in samples and the average level of Ni¡ As¡ and V pollution in other samples). Igeo indicated the moderate to severe pollution of some samples to Pb¡ Cd¡ Cu¡ and Zn while no to moderate pollution against Ni¡ As¡ and V in other samples. EF for Pb¡ Cd¡ Cu¡ and Zn showed a significant pollution in some samples and other samples represented the least pollution against Ni¡ As¡ and V.
Results showed that the concentrations of heavy metals in dust samples were higher than control samples in Masjed-e- Soleiman. Thus¡ the classification of pollution in street dust in Masjed-e- Soleiman is as follows: IPI> EF> Igeo ≈ PI.

Heavy metals are seriously dangerous for the human body and their accumulation in the body can cause pathological changes in the organs and this can result in cardiovascular, liver and bone diseases, and even cancer. Human is exposed daily to these pollutants via consumption of food and water.
Considering the cumulative properties of these metals in plant organs, the amount of Cr, Mn, and Fe in soil and leaf, stem, and root tissues of cabbage, lettuce, spinach, and onions in Karaj City were investigated. For this purpose, 15 samples were randomly collected from each part of the plants, and then, the density of heavy metals was measured via atomic absorption spectrometer after cleansing, grinding, drying, and acid digestion. The data were then analyzed using SPSS software.
It was found that leaves of spinach, cabbage, lettuce, and onion have higher concentrations of Cr, Mn, and Fe rather than their stems and roots. The roots of plants contain the least densities of metals. Moreover, concentrations of Fe, Cr, and Mn in soil were 11.87, 3.99 and 17.78 mg/kg, respectively. This was due to the high transportation of these metals to air-related parts of the plant like leaves. This research also showed that the densities of Cr, Mn, and Fe in leaves of studied spinach, onion, cabbage, and lettuce exceeded the FAO/WHO standard limitations (0.15, 0.3, and 0.3 mg/kg for Cr, Fe and Mn, respectively).
Due to the high concentrations of Cr, Mn, and Fe in studied vegetables in Karaj City, the consumption of these kinds of vegetables by citizens must be taken into consideration by regulatory agencies.

Fluoride has both beneficial and detrimental effects on health. Therefore, it is important to determine its concentration in drinking water. Dental fluorosis and skeletal fluorosis are health effects caused by long term exposure to high levels of fluoride in drinking water. The aim of this research was to investigate fluoride removal using modified diatomite-supported ferric oxide nanoparticles and to determine the adsorption kinetics and isotherm.
This fundamental and practical study was performed at laboratory scale. The effects of pH (3.5-9.5), contact time (20-100 min), adsorbent dosage (1-5 g/L), and initial concentrations of fluoride (5-25 mg/L) on the adsorption efficiency were evaluated. The properties of adsorbent were investigated using XRD, XRF, FTIR and FESEM. Finally, the suitability of pseudo first and second order kinetics, and Langmuir and Freundlich isotherms for the data were investigated.
This study showed that the removal efficiency of F- increased with increase in contact time, decrease in pH, increase in adsorbent dose, and increase in initial fluoride concentration. The highest removal efficiency was observed at pH=3.5, 60 minutes contact time, and 3 g/L of adsorbent dose in the initial concentration of 5 mg/L F-. Pseudo first order and Freundlich were the best fitted kinetic and isotherm models, respectively, for describing F- adsorption process.
The present study indicates that the modified diatomite-supported ferric oxide nanoparticles can be used as an effective and environmentally friendly biosorbent for the removal of fluoride ions from aqueous solutions.

Conventional methods of leachate treatment are inefficient due to high pollution loads and characteristics of the leachate. In recent years, an integrated method has been developed considerably. The aim of this research was to evaluate the effect of powdered activated carbon on the treatment of landfill leachate of Kermanshah City by a columnar aerobic sequencing batch reactor.
This study was carried out in three reactors having a total volume of 2000 mL and each having an effective volume of 600 mL in the bench scale. To the reactors 2 and 3 that were similar from environmental conditions and operation point of view with reactor 1 (with no carbon powder), 5 and 10 g/L of PAC were added, respectively. The effects of different doses of PAC (0, 5, 10 g/L) and hydraulic detention times (HRT = 48, 96, 144 h) were investigated in order to remove the Chemical Oxygen Demand (COD) and ammonia nitrogen (NH3-N) from the leachate. The efficiency was investigated using two -way ANOVA test in SPSS software (Ver. 16).
The results of two-way ANOVA showed that there was a significant difference (P-value=0.001) between the removal efficiency of COD and NH3–N at different HRTs with different doses of PAC. The highest removal efficiency achieved at HRT=144 h for COD and NH3-N was in Reactor 1 were 50.11 ± 4.42 and 19.85 ± 1.49%; in reactor 2: 55.67 ± 1.6 and 25.7 ± 0.89%; and in reactor 3: 58.02 ± 3.99and 25.48 ± 1.7%, respectively.
It can be concluded that the combination of biological - activated carbon compared with the biological process, can remove COD and NH3–N of strong sewages such as landfill leachate, although achieving standard treatments using this method is not possible.

Bioaugmentation is a superior technique in bioremediation of contaminated soils with petroleum hydrocarbons. The aim of this study was to evaluate the effect of isolated bacteria from activated sludge of Asalouyeh special zone municipal wastewater treatment for bioaugmentation of kerosene-contaminated soils and to study the growth of isolated bacteria in the presence of different concentrations of this product.
Sampling of activated sludge was carried out from two treatment plants in Asalouyeh zone. Isolation of degrading bacteria was performed by culturing the samples on basal mineral medium. Emulsification test and evaluating the kinetic growth of bacteria were carried out in different concentrations of kerosene. Isolated bacteria were inoculated to polluted soils with kerosene oil compound for bioaugmentation and measuring their bioremediation potentials and the rate of biodegradation were measured by InfraRed (IR) spectroscopy.
In this study, three bacterias: Pseudomonas putida, Serratia marcescens, and Proteus mirabilis were isolated and identified as kerosene degrading bacterias from activated sludge. P. putida was recognized as the most powerful degrading bacterium of this oil product according to the emulsification tests, measuring the growth of bacteria in various concentrations of kerosene, the results of bioaugmentation of contaminated column of soil with kerosene, and reducing the level of Total Petroleum Hydrocarbons (TPHs). This bacterium with emulsification rate of 3.8 could reduce 71.03% of TPHs within 30 days.
According to the adaption of Pseudomonas putida, Serratia marcescens, and Proteus mirabilis in activated sludge with variety of pollutants in sewage, they can be used as non-indigenous bacteria for bioaugmentation and cleaning up the soil contaminated petroleum hydrocarbons.

Money as a common tool is exchanged between people all over the world. Thus, it can be a source of chemical and biological contaminations causing serious diseases. The purpose of this research was to determine bacterial contamination of the currency notes and coins collected in Kermanshah.
160 currency notes and 96 coins were randomly chosen from different jobs and parts of the city. Total count experiment was done and bacteria were identified and isolated through standard methods.
Average total count in 1000, 2000, 5000, 10000, and 20000 Rials currency notes were 147.6, 147.8, 148.5, 96.3, and 87.9 and in 500, 1000, and 2000 Rials coins were 104.66, 77.66, and 96.56 CFU/cm2, respectively. The research showed that currency notes carries more bacterial load than coins (P In summary, the most important microorganisms isolated from currency notes and coins (E.coli and Staphylococcus aureus) were pathogenic, causing serious food poisoning and gastroenteritis infectious. Therefore, preventing food from cross contamination with money is necessary.

Nowadays, indicators related to human physiology have special roles in human bioclimatic and environmental studies. One of these indices is Physiological Equivalent Temperature (PET). In the present study, trends of physiological equivalent temperature index over the past half century, which is the foundation of plans, especially in the field of health and environment, were evaluated in four climatic regions of Iran (Mashhad, Rasht, Esfahan, Tabriz and Bandar Abbas).
Material and In this study, the data required to calculate the heat stress in the daily scale for 50 years during 1961-2010 were obtained from Iranian Meteorological Organization. Then, PET index at the daily scale was calculated and values greater than 35°C were identified for warm periods of the year. In the next step, the seasonal trends were analyzed by Mann-Kendall test.
Changes in the frequency of days with heat stress in stations of Mashhad, Isfahan, and Tabriz have been rising during spring and summer. In other words, the greatest amount of positive change has occurred over the long-term average in these cities. The highest frequency of hot days was observed in Rasht and Bandar Abbas stations. The main reason for this subject has to do with how adjacent they were to the sea and the high rate of evaporation in such areas.
The 1980s-1990s have been allocated as the most days of hot stress. Upward trend of thermal stress occurring in the studied stations has increased the attention to the problem of heat stress and disease (thermal attack, fainting, muscle cramps) from the field of planning and management of the crisis.

Dyes are important pollutants that lead to producing serious hazards to human, other animals and organisms. Dyes are not biodegradable by aerobic treatment processes. Therefore, their removal from industrial effluents before discharging into the environment requires extreme and great attention. The aim of this research was to evaluate removal efficacy of methyl orange dye from aqueous solutions using NiFe2O4 nanoparticles.
This study was an empirical investigation in which NiFe2O4 nanoparticles were synthesized by co-precipitation method and were used as an adsorbent for the removal of methyl orange from aqueous solution. NiFe2O4 nanoparticles were characterized using X-Ray Diffraction (XRD), Transmission Electronic Microscopy (TEM), pHpzc and SEM-EDX elemental analysis methods. Experiments were conducted discontinuously using 20 mL methyl orange solution of 40 mg/L. The effect of variables such as pH (2-8), amount of adsorbent (0.009-0.07 g) and contact time (2-70 min) on the efficacy of dye removal was studied. Finally, experimental data were compared by Langmuir, Freundlich, and Temkin isotherms and pseudo-first-order and pseudo-second-order kinetic models.
TEM images showed that the NiFe2O4 nanoparticles had spherical shapes with the size of 12 nm. The results indicated that removal efficiency increased up to 0.04 g adsorbent and 20 min contact time. The optimum pH for methyl range removal was 2. Moreover, under these conditions, the adsorption process followed the Langmuir adsorption isotherm with a correlation coefficient of 0.995 and pseudo-second-order kinetic model with a correlation coefficient of 0.999. Also, the maximum adsorption capacity of the prepared adsorbent was 135 (mg/g) for Langmuir isotherm.
The NiFe2O4 nanoparticles are effective and available adsorbents for the removal of methyl orange from industrial wastewater.

Surfactants can be found in soaps, detergents, pharmaceutical products, personal care products, as well as in leather industries. In this study, adsorption of Sodium Dodecyl Sulfate (SDS) on magnetic multi-walled carbon nanotubes in the aqueous solutions was investigated.
Surfactant concentration, adsorbent dosage, and pH values were considered as variables. Residual surfactant was measured using methylene blue method and adsorbent characteristic was determined by X-Ray diffraction and Fourier transform infrared spectroscopic analysis. Adsorption capacity, adsorption isotherm, and kinetic reaction were also investigated.
Adsorption investigations demonstrated that the increase in initial SDS concentration or pH values, led to the decrease in SDS adsorption. Conversely, the same result was achieved by decreasing adsorbent dosage. After 120 min SDS adsorption became stable. By increasing in SDS concentration from 15 to 150 mg/L, adsorption capacity improved from 8 to 61 mg/g. Isotherm and kinetic data demonstrated that experimental data pursued Langmuir isotherm (R2=0.993) and pseudo-second order equation (R2=0.992).
Magnetic multiwall carbon nanotubes can be used as an effective and useful sorbent for SDS removal due to several advantages including: high adsorption capacity, relatively low equilibrium time, and easy separation of magnetic multiwall carbon nanotubes from aqueous solutions.

B> The continuous increase in solid waste generation worldwide due to population growth and industrialization, calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, Life Cycle Assessment (LCA) is a tool which can contribute to answering that call. The aim of this study was to evaluate environmental pollutants resulting from various treatment options including anaerobic digestion, incineration, and landfill of Municipal Solid Waste (MSW) generated daily in Tehran.
First, the physical properties of the waste and consumption of inputs in the study area were determined from September to October, 2014- 2015. Then the different steps of LCA in relation to each of the subsystems were followed (with SimaPro software). Finally, the results based on the CML Baseline 2000 were presented and analyzed.
It was found that when the higher rate of separation and processing in any subsystems increases, the emission of environmental pollutants decreases, so that the global warming potential, acidification, eutrophication, and abiotic depletion as the most important impact categories in the subsystems of anaerobic digestion were obtained as -125935 kg CO2/day, -449 kg SO2/day, -1690 kg PO43-/day and -0.43 kg Sb/day, respectively and in incineration were obtained as -264872 kg CO2/day, -974 kg SO2/day, -3471 kg PO43-/day and -0.76 kg Sb/day, respectively, while in the landfill subsystem, they were estimated to be 74478 kg CO2/day, 362 kg SO2/day, 118 kg PO43-/day, and 0.13 kg Sb/day, respectively.
According to the constituent processes of each of the subsystems and the results of the evaluation of exhaust emissions subsystems, it can be concluded that in an integrated system of waste management, the energy-generating systems such as anaerobic digestion and incineration should be as the first priority and the traditional subsystems such as landfill should be as the last priority.

Compost is beneficial for conditioning the structure and nutrient content of soil. Toxic metals are the most important contaminants that can enter the food chain through the compost products and affect human health. The aim of this study was to assess the arsenic, mercury, cadmium, and lead levels in six brands of vermicompost produced from the organic solid wastes in Tehran and to compare the amounts with the international and national standard levels.
This was a descriptive - analytical study in which samples of six brands of vermicompost products were randomly selected from the distribution centers in Tehran, and from each brand four samples were prepared (24 samples). Then the samples were extracted using the TCLP (Toxicity Characteristic Leaching Procedure) method and after filtration the metal concentrations were measured by Inductively Coupled Plasma (ICP). All data were analyzed using Excel software.
The means and standard deviations of the toxic metals concentrations (arsenic, mercury, cadmium, and lead) in the collected samples of each brand were reported in terms of mg/kg. The maximum concentrations of these toxic metals were 7.45, 0.15, 0.19, and 79.95 mg/kg, respectively.
The results indicated that the levels of toxic metals in the vermicompost samples derived from the municipal solid waste in Tehran were lower than the permissible limits of the national and international standards.