فصلنامه پژوهش در بهداشت محیط
سال هفتم شماره 4 (زمستان 1400)

The present study stimulated the groundwater quality parameters of Zeidoun plain including Sodium Adsorption Ratio (SAR), Electrical Conductivity (EC), Total Dissolved Solids (TDS), using ANN and ANN-GA models and in the end compare their results with measured data. The input data for TDS quality parameter consist of Na, EC, Ca, Mg, SO4 and SAR, for SAR including the Na, TDS, Hco3, Ca and Mg and quality parameter of EC contains Ca, Mg, SO4, Na and SAR, gathered from 2011 to 2018.The results showed that in ANN and ANN-GA models, the highest accuracy of SAR simulation in the model with sigmoid tangent function, in EC simulator model, the highest accuracy in ANN and ANN-GA models, respectively, related to logarithm stimulus functions. Sigmoid and tangent is sigmoid. Also in ANN and ANN-GA models, the highest accuracy of TDS simulation was obtained in the model with sigmoid tangent stimulus and sigmoid logarithm, respectively. so that the MAE and RMSE statistics have the minimum and R^2 has the maximum value for the model. In general, according to the obtained results, the accuracy of ANN-GA model is higher than ANN model, to simulate the groundwater quality parameters of Zeidoun plain. Therefore, the use of artificial neural network model along with genetic algorithm is a good tool to simulate high quality groundwater quality parameters, without the need for measurement and laboratory work, which requires high time and cost.

Sediment monitoring in aquatic environments is very important due to long-term exposure of various pollutants. This study was conducted to monitor the pollution of some heavy metals (Cd, Cu, Fe, Pb and Zn) in the surface sediments of Anzali wetland.

For this purpose, sediment samples were collected from east, west and central parts of the wetland in different seasons of 2020. Heavy metals contamination zoning for sediments in the study area was performed using Arc GIS 10.7

The results showed that the highest level of contaminants were obtained in the western part of the wetland. The average concentrations of heavy metals in the sediments were related to Cu (18.47), Zn (74.15), Cd (0.67), Pb (12.05) and Fe (1.97) mg. kg-1 in the western part. The pattern of changes of studied metals was in conformity with Cd 0.05) between Pb, Cu and Zn. According to the zoning map of the parts located in the middle of the center to the west of the wetland, higher amounts of metals have been deposited in its sediments.

In general, various human activities and the development of industries and the existence of agricultural lands in the area of Anzali Wetland and incoming rivers can be considered as factors affecting pollution. Therefore, with continuous biological and ecological monitoring of the wetland, it is possible to estimate the amount of heavy metals and the share of each in the wetland. Also, management in order to protect and monitor the wetland seems necessary.

Today, plastics have a special place among the various issues that are considered as sources of pollution. Most of these plastics are in the dimensions of Micro and Nano. One of the most important sources of Microplastics transfer is wastewater treatment plants, where a large amount of these particles, which are not removed in the treatment process, enter the receiving environment. The purpose of this study is to first determine the optimal method of identifying and extracting particles from wastewater for counting and then to investigate the amount of removal and also to determine the amount of particles leaving the treatment plant.Sampling of inlet and outlet of wastewater treatment plant located in Mazandaran province was done seasonally in three seasons of spring, summer and autumn to determine in which season of the year, the amount of microplastics in wastewater increases or decreases. Also, the extraction and identification method is based on acid washing operation and based on creating a density difference, which has resulted in a favorable result with optimization and innovation.Using this method, the amount of Microparticles and microfibers along with the size and shape of the particle was determined and it was determined to what extent the normal treatment process is able to separate Microplastics from wastewater. The treatment plant can remove an average of 95% of the particles, which means that the remaining 5% of the particles are removed with the effluent and enter the aqueous environment.Finally, it was found that the determined laboratory method can identify and extract Microplastics in very small sizes to a very desirable extent. Also, determining the appropriate parameters of liquid volume, salt consumption and the use of dual capacity iron increased the efficiency compared to other methods and led to the identification of smaller particles than previous research.

Due to the high pollutant load of paper mill effluent and in order to decrease contaminants, effluent should be treated before being discharged into the environment.

After collecting samples of paper mill effluent in Babol city, high levels of COD and TSS were found. Therefore, polymeric coagulants such as iron sulfate, ferric chloride, polyaluminum chloride, and alum were employed, as well as anionic and cationic polyacrylamide flocculants.

Ferrous sulfate, ferric chloride, aluminum polychloride and alum at their optimum pH removed 12%, 13.5%, 15%, and 23% of effluent COD, respectively, as well as 45.5%, 47%, 49% and 52% of TSS. Then, by examining the coagulants concentration effect, alum with an optimal concentration of 1 g/l removed 23.7% COD and 56.4% TSS. Additionally, the effects of anionic and cationic polymeric coagulants were studied. According to the results, using an anionic coagulant at a concentration of 0.004 g / l in combination with the optimal amount of alum resulted in the elimination of 48.6 % COD and 69.6 % TSS.

Based on the results, the coagulation and sedimentation methods can be utilized to treat the effluent of paper mills. Furthermore, using an alum coagulant and an anionic coagulant at the same time improves the efficiency of the coagulation and flocculation processes in removing pollutants from paper mill effluent.

Assessing the health effects of air pollution can provide useful information for health policy . AirQ + software is a tool for determining and modeling the health effects attributed to air pollutants such as O3, NO2, PM10 and PM2.5. The aim of this study was to quantify the health effects of PM2.5 pollutants in the air of Mashhad.

In order to present this analytical study, air quality data were obtained in 2019 from the General Department of Environment of the province and the Environmental Pollutants Monitoring Center of Mashhad Municipality. Hourly data of each validated station and stations that less than 75% of the data were not registered or were not valid were eliminate. Demographic and meteorological information were also obtained from relevant organizations. AirQ + software was used to quantify the health effects of suspended particles. The desired cut-off concentration was 10 μg / m3 according to WHO guidelines.

The results show that the total death rate attributed to PM2.5 in 2019 was about 1069 cases, which is about 9.5% of the total deaths in Mashhad. In the long term exposure, the rate of premature death attributed to PM2.5 due to COPD in that year was about 14%, due to cancer about 12%, due to IHD about 6% and due to stroke about 8% of the total deaths in Mashhad in the upper25 years old population.

Among air pollutants, PM2.5 due to its special structure composition can be one of the risk factors for public health. This study does not consider the synergistic effects of air pollutants, which is due to the lack of studies worldwide. If the synergistic effects of pollutants are taken into account, the rate of deaths attributed to air pollution could be much higher than currently estimated.

Vegetables are among the valuable foods. However, in addition to essential elements, they may contain toxins in excess of permissible concentrations, which has raised many concerns about the quality and safety of these products and human health. Therefore, the present study was conducted to investigate the effect of atmospheric pollutants of carbon dioxide, gasoline and acid rain on the resistance of basil and parsley.

This factorial study was performed based on a completely randomized design with 3 replications and 54 treatments . In this study, CO2 with three concentrations of 0, 1000 and, 1800 ppm, gasoline with three conditions without adding gasoline, with ordinary gasoline and with the addition of super gasoline, and acidic solution at two levels of pH 4 and 6 were studied. It should be noted that distilled water with pH = 7 was selected as a control treatment.

The results showed that the concentration of 1000 ppm carbon dioxide increased plant yield by 178.63%, while its concentration up to 1800 ppm, led to the destruction of the plant in two days. It was also found that super gasoline due to the high-octane number and supplements in it has a less polluting effect (5.7%) on the plant than regular gasoline. In addition, no significant difference was observed between different concentrations of acidic solution on plant resistance. In this experiment, parsley showed more resistance to contaminants than basil.

carbon dioxide than other pollutants and also its key role in global warming, we need effective management to promote public health and control the production sources of this gas in the atmosphere.

Today, due to the dangers of chemical preservatives in food, alternative and safe methods such as the use of natural extracts of natural plants have increased. The aim of this study was to evaluate the antibacterial effects of Kenar fruit extract on the bacteria of Salmonella, Shigella, Escherichia coli and Bacillus cereus.

We prepared Kenar fruit extract by soaking or immersing in methanol. After concentrating by rotary device, we prepared 9 concentrations of the extract serially, then performed antibiogram by well method and determined MIC and MBC. We also used volumetric-volumetric solution of methanol and dimethyl sulfoxide in equal proportions as negative control and control disks and standard commercial antibiotics as positive control.

Based on the results, the diameter of inhition zone for dropletsfor Shigella, Salmonella, Bacillus cereus and Escherichia coli at a concentration of 80 mg/mL of methanolic extract of the plant was 24, 17, 59 and 19 mm, respectively. It was also found that methanolic extract of Kenar fruit had very good antibacterial effects on gram-positive bacterium Bacillus cereus compared to other target bacteria (which are gram-negative) and had significant growth inhibition and bactericidal effects at very low concentrations.

The results showed that methanolic extract had very favorable antibacterial effects against four target bacteria. Therefore, it can be said that the compounds of methanolic extract of this plant can be used as important components of various products in the food, pharmaceutical, cosmetic and health industries.

The Covid-19 pandemic has had a significant impact on various aspects of people's lives. Different countries have adopted different policies to combat this disease. The purpose of this study is to review the policies adopted in the field of environmental health to combat Covid-19 in Iran.

This qualitative study was performed by document analysis method in February 2022. The research population was purposefully determined in consultation with six health policy and environmental health experts. For this purpose, the policies of the National Corona Headquarters as the highest policy reference in the field of Covid-19 were studied. Data analysis was performed using conventional content analysis method and MAXQDA software version 12.

In total, 255 codes, 25 sub-themes and 7 main themes in the field of environmental health to combat Covid-19 were identified. Public social activities, public environmental health, social distancing, borders control, infrastructure development, procurement and distribution of personal protective and disinfection equipment, and monitoring were the main themes identified in this research.

So far, a range of different policies in the field of environmental health have been adopted in Iran to deal with Covid-19. Local and international evidence, experiences of other countries, and socio-economic and political determinants play significant roles in policy development, policy reform, or abandoning previous policies.