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Study of Heavy Metals in the Atmospheric Deposition in Zanjan, Iran
Z Farahmand Kia, M.r Mehrasbi, M.s Sekhawatju, A.sh Hasanalizadeh, Z Ramezanzadeh,
Volume 2, Issue 4 (9 2010)
Abstract

Backgrounds and Objectives : Heavy metals in dust can enter to the human body through ingestion andinhalation. They can pollute the water and soil resources via atmospheric precipitation and accumulate in the plants tissue and enter human body by water and food. The aim of this study was measurement of the heavy metals in wet and dry atmospheric precipitation and effects of pollution sources at the ground surface on the concentration of heavy metals in the atmospheric precipitations.
Materials and Methods: In this study the zanjan city was divided into 5 zones and wet and dry precipitations were collected in autumn, winter and spring (2008- 2009) from zones. The concentrations of Pb, Cd, Cr and Zn the collected precipitations were determined by Atomic Absorption spectroscopy method.
Results: The averages of concentrations of Pb, Cd, Cr and Zn were 0.082, 0.286, 0.018, and 0.009 (mg/m 2.d)respectively. The correlation coefficients between Pb-Zn was 0.8 (P<0.01) and for Cr-Cd, Cd-Pb, and Cr-Pb were 0.89, 0.58 and 0.61 respectively.
Conclusion: The results showed that the industrial sources of heavy metals play the main role in concentration of heavy metals in wet and dry atmospheric precipitation in Zanjan.The correlation coefficients showed that the lead and zinc result from a common source. This source can be the lead and zinc factories locating around the city. The measurement of heavy metals in atmospheric precipitation shows the effects of anthropogenic sources in air quality. The heavy metals concentration in atmospheric precipitation can be use as air pollution index.


The determination of total microbial count and prevalence of Salmonella in the shrimp supply in Khuzestan province
Mj Sana, Z Hosseini Siahi,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Food-borne diseases are among the most important public health problems. Among them, Salmonella is one of the most important food pathogens. Different Salmonella serotypes enter body through food and causes food infections in consumers. One of the most important evaluation criteria for health is to determine the microbial load of food.
Materials and Methods: In this study, 245 shrimp samples supplied in Khuzestan province were taken randomly. The samples kept on ice were transferred to the laboratory and immediately tested microbiologically.     
Results:  In this study, in 50.2 percent of the samples, the average number of bacteria per mL of the rinse water used to rinse the shrimps was 2200 bacteria, in 29.8 percent of the samples, it was 13600 bacteria and in 20.0 percent of the samples, the average number of bacteria per mL of the rinse water, it was 36700 bacteria. Based on these results, the average number of bacteria in the total samples was 20000 bacteria per mL rinse water. Out of the total samples assessed 33 samples were positive and 212 were negative for Salmonella, showing a 13.4 percent prevalence of Salmonella contamination in the shrimp production in Khuzestan Province.
Conclusion: Due to the microbial load and Salmonella contamination in shrimp supply in the province of Khuzestan raw or undercooked consumption of shrimps can increase the possibility of problems for consumers.
 

Evaluation of the performance of Tehran drinking water treatment plants in removing nanoplastics and microplastics
Fatemeh Tabatabaei, Roya Mafigholami, Hamid Moghimi, Sanaz Khoramipour,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: Microplastics can have harmful effects on living things, including humans. These particles have been identified in all water, soil, and food sources. Among these, freshwater resources are more important, because they are considered a water source for humans through drinking water treatment plants (DWTPs). Therefore, this study investigates the performance of Tehran DWTPs in removing these particles.
Materials and Methods: In this study, the performance of three DWTPs in Tehran in removing these particles was investigated. In most studies worldwide, particles larger than 1 µm were examined, but in this study, nanoplastic particles smaller than 1 µm, as well as the effect of the warm and cold seasons of the year on the concentration of these particles were also examined.
Results: According to the results of the study, the amount of micro and nanoplastic particles at the inlet of treatment plants in the warm season of the year was 2569 ± 309 to 3918 ± 425 MP/L, and the output was 1492 ± 32 to 2279 ± 146 MP/L, which indicates an increase in these particles in the warm season. As a result, the studied treatment plants were only able to remove 32.1 to 59.9% of these particles. In addition, using electron microscopy, MPs were classified into three categories in terms of appearance: fiber, fragment, and film. This study completes the knowledge of MPs in this area.
Conclusion: Based on the results of this study, Tehran DWTPs have poor performance in removing these particles.
 

Cigarette butts pollution on Guilan beaches and the main factors affecting their distribution
Sanaz Ghaffari, Alireza Riyahi Bakhtiari, Seyed Mahmoud Ghasempouri, Ali Nasrolahi,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Today, cigarette butts have become one of the most significant forms of waste. This study aims to assess the level of cigarette butts pollution along the Guilan coasts and explore the factors influencing their distribution. Additionally, this study discusses experiences and management options related to this issue.
Materials and Methods: In this study, we implemented a standard sampling method adapted from the "NOAA Marine Debris Program" to collect samples from eight beaches. Each station yielded 18 square quadrant measuring 1 × 1 m2. We estimated the severity of cigarette butt pollution along the Iranian coastline and conducted a review of published articles on the harmful effects of cigarette butts.
Results: The density of cigarette butts ranged from 0.22 to 2.11 items/m2. Bojagh National Park showed the lowest contamination of cigarette butts, while Bandar Anzali exhibited the highest. The results indicate an increase in cigarette butt pollution on beaches in densely populated cities compared to less developed coastal areas. Moreover, stations corresponding to tourist beaches and coasts with gentle slopes have a higher potential for cigarette butt accumulation. The level of cigarette butts pollution along the coasts of Bandar Anzali may be attributed to the extensive tourism activities on these beaches.
Conclusion: Given the high level of cigarette butt pollution on crowded coasts, it is imperative to identify beaches with a higher potential for waste accumulation and implement plans for coastal waste cleanup. Furthermore, effective management programs should be developed to promote cultural awareness and reduce cigarette butt contamination.
 

A comparison on the effects of alginate and chitosan in the synthesis of granular zeolite adsorbents used for arsenic removal
Maryam Tahmasebpoor, Leila Sanaei, Masoomeh Chaharkam,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Zeolites are among the widely used adsorbents for the removal of arsenic-toxic pollutants. The objective of this study is to prepare granulated zeolite adsorbents using chitosan (CS/Fe-Clin) and alginate (Alg/Fe-Clin) and compare them in terms of physical appearance and arsenic adsorption efficiency.
Materials and Methods: Granular adsorbents were prepared via the ionotropic gelation method. The effects of the type and concentration of the cross-linking solution and the initial ratio of materials in granules formation, as well as the effect of initial arsenic concentration, and the amount of adsorbent used on the adsorption efficiency, were investigated. SEM, XRD, FTIR, and AAS analyses were used to confirm the results. Equilibrium data were matched with Freundlich and Langmuir isotherms.
Results: A weight percentage of 2 % iron chloride (III) and an initial ratio of 1:4 of alginate: nanocomposite for Alg/Fe-Clin and a weight percentage of 2 % (1 % sodium hydroxide + 1 % sodium tripolyphosphate) and an initial ratio of 1:3 of chitosan: nanocomposite for CS/Fe-Clin were chosen as the optimal values. Maximum adsorption efficiency of Alg/Fe-Clin and CS/Fe-Clin adsorbents was determined 88.1 and 92.9 % at dosages of 0.6 and 1 g/L and at initial concentrations of 200 and 300 µg/L, respectively. The qmax values for Alg/Fe-Clin and CS/Fe-Clin adsorbents were 11.11 and 10 mg/g, respectively. Results better fitted with Freundlich isotherm.
Conclusion: Due to the proper adsorption capacity, both synthesized adsorbents showed the ability to effectively remove arsenic; whoever, alginate binder was more efficient.
 

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