فصلنامه پژوهش در بهداشت محیط
سال هشتم شماره 1 (بهار 1401)

One of the complications of transportation in cities is noise pollution caused by vehicles. Today, noise in urban environments is an important issue in the field of public health. Due to the negative effects of noise pollution on human health and well-being, it is necessary to identify and understand these effects on the health of exposed people. In this study, the type of traffic axis composition of the highway was identified and the type of traffic information required was identified by identifying the locations for the sound station along the highway axis and preparing sound data and identifying the factors affecting sound propagation. At each sampling station, the required variables in the intervals of 7: 30-9: 30, 12: 30-14: 30, 18: 30-20: 30, 23: 30-1: 30 And 3: 30-5: 30 and different seasons of the year were measured and recorded for modeling. The results show that the comparison of the average parameters of noise pollution in different stations of Shahid Kalantari Highway at a significant level of 5% showed that the highest amount of noise and sound indicators measured are related to the first station of Abadgaran with the amount of deci, respectively. Bell is 79.61 dB, the entrance road to Kuhsangi is about 80 dB and the lowest station of Hafez Square is about 58 dB. The parameters Lmax, Leq, L10, L50 and L90 are visually uniform distribution of results in the fit line range. According to the results of this study, it is announced that in all seasons of the year, the average equivalent sound level in all stations studied is higher than the recommended daily ambient sound level in the Iranian open air sound standard. While the standard sound level in residential areas is 55 decibels during the day and 45 decibels at night.

Emitted pollutants in indoor environment of printing industries are the most serious risks to labor’s health according to WHO. The health effects of these pollutants range from acute diseases like eye irritation to chronic effects such as cancer and DNA damage.

To study air pollution in indoor environment of the printing industry, using EPA methodology and ranked set sampling, samples were collected and then analysed through gas chromatography.

Based on the results, despite the concentration profile at the sampling sites, the total concentration of very volatile and volatile organic compounds at the nearest point to the dye tank, the location of the operator at a distance of one and two meters from the heliogravure machine, and the general working space were 20.83%, 5.41%, 1.85% and 1.46%, respectively . About 52% of the observed putants were ink organic solvents, 38% were sulfur compounds and 52% were nitrogen compounds. About 24% of pollutants have a complex structure of 12 carbons or more. The concentrations of pollutants observed not only exceed OSHA and NIOSH standards but also very high compared to similar international research; so that they are in the range of danger code announcement and have worrying health effects on employees.

The results indicate the need for urgent intervention to reduce pollution in the printing industry. The preferred method for managing indoor air quality is control or replace the source of pollution, proper air conditioning equipment use, and simultaneous use of filters and air conditioning system to reduce emissions.

The turbidity of treated water is measured as an important parameter in determining the quality of drinking or industrial water in all treatment plants. Due to the importance of the prevalence of pathogens such as Giardia and Cryptosporidium, which cause dangerous diseases such as dysentery, the relationship between reducing turbidity and increasing the elimination of these microorganisms has been proven in studies.

In this study, an artificial neural network (ANN) model and multiple linear regression(MLR) were developed and their performance was compared to predict the turbidity of treated water of Tabas water treatment plant. Total dissolved solids, pH, temperature and input turbidity of raw water were used as input parameters of the models in the predictions. The best backpropagation algorithm and number of neurons were determined to optimize the model architecture.

The results showed that the Levenberg–Marquardt algorithm was selected as the best algorithm and the number of optimal neurons was determined to be 16.Also, the results of the sensitivity analysis of the neural network model showed that the input turbidity with a value of 29% is the most important parameter in the development of the ANN model.

The results of correlation coefficient of MLR and ANN models were obtained for training data 0.63 and 0.8921 and for testing data 0.60 and 0.8571, respectively, which show the superiority of ANN model in Predicting the turbidity of the output of Tabas water treatment plant.

River sediments are one of the most important environmental indicators to determine the level of pollution in ecosystems. The purpose of this study is to investigate the quality of Mahabad river sediments in West Azerbaijan province.

For this purpose, 15 samples of surface sediments (from 0-20 cm depth) of the river were collected. Physical and chemical properties of sediments including: texture, organic matter, Total neutralizing Value, electrical conductivity, pH, and total amount of heavy metals was measured. Correlation between physical and chemical properties of sediments with heavy metals was performed using Pearson correlation test in SPSS software.

Mean total concentrations of heavy metals including arsenic, nickel, zinc, cadmium, lead, cobalt, chromium and copper, were respectively 13.29, 63.40, 60.53, 0.47, 0.39, 18.40, 44.47 and 25.93 mg / kg. Arsenic, nickel and cadmium had higher levels of standard concentrations of heavy metals in sediments. According to the results of Pearson correlation coefficient, cation exchange capacity, organic matter, clay and silt have the most significant positive correlation with the distribution of heavy metals. On the other hand, except for copper, chromium and cobalt, all other elements show a significant positive correlation of 99%. The results showed that all the elements have the same origin.

According to the separation of upstream and downstream samples, it can be said that the concentration of elements in the upstream was due to natural factors, and downstream, heavy metal pollution has increased with increasing human activity.

Human activities, especially in construction and agriculture, introduce large amounts of nitrogen, phosphorus and organic matter into aquatic ecosystems.

In this study, municipal and industrial wastewater samples were obtained from wastewater treatment plant No. 1 of Parkand Abad and wastewater treatment plant of Kalat industrial park, respectively. Before starting the reactor, wastewater samples were allowed to settle for 2 h to remove coarse suspended solids and then sterilizes in autoclave. Chlorella vulgaris was purchased from Jahad Daneshgahi of Mashhad and grown in specific culture media under temperature 25±2°C, photoperiod of 14 h light and 10 h dark, monochrome light with intensity of 5000±350 lux, pH of 7-8.5 and time of 10 d. Then 1 L of the above solution were transferred to three 10 L reactors loaded with municipal, industrial and culture media and aerated under sterile conditions in the presence of light for 10 d. In predetermined time intervals (each 2 d), 100 mL sample were taken from reactors and COD, total phosphorous, total nitrogen, pH and chlorophyll a measured.

Removal efficiency of COD, total nitrogen, and phosphorus in municipal, industrial and culture media by Chlorella vulgaris was 63.69, 12.52, and 13.79%, 66.57, 34, and 50.18%, respectively. According to results, the efficacy of algae for removal of COD was higher than other parameters, while that for total nitrogen was lowest. Efficacy of algae for removing pollutants from industrial was better than those in domestic wastewater.

The results of this study showed that municipal and industrial media could be a suitable culture media for growing Chlorella vulgaris algae. It also has the ability to remove nutrients from wastewaters.

Polycyclic aromatic hydrocarbons are a large group of ubiquitous environmental pollutants with teratogenic, mutagenic and carcinogenic potential, which are products of incomplete combustion and pyrolysis of fossil fuels and combustion of organic matter. This study was performed to determine and identify the origin, concentration and source of PAHs compounds in surface soils of industrial areas, Hamedan, Iran, in 2021. In this descriptive study, 36 surface soil specimens were collected from 12 sampling sites of industrial areas. After extraction of analytes based on the soxhlet method, the gas chromatography/mass spectrometry (GC–MS) method was used for the determination of PAHs compounds in the samples. Molecular diagnostic ratios (MDRs) were used to determine the origin of PAH compounds. Furthermore, the amounts of pH, electrical conductivity (EC) and total organic carbon (TOC) parameters of soil samples were measured. Statistical data processing was performed using SPSS statistics 20 software. The results showed that the total concentrations of 16 identified isomers ranged from 2417 to 16279 µg/kg with a median of 7675 µg/kg and with a dominance of 4-6 rings hydrocarbons (66% of total PAHs). Furthermore fluoranthene (Fla), pyrene (Pyr) and benzo(b)fluoranthene (BbF) were the most abundant compounds in soil and the average of compounds such as benzo(a)anthracene (BaA), benzo(b)fluoranthene (BbF), benzo(a)pyrene (BaP) and dibenzo(a,h)anthracene (DB(ah)A) were higher than MPC established by The Dutch Ministry of Health, Welfare and Sport (MHWS). The results of the MDRs method indicated that both pyrogenic and petrogenic sources are the origin of PAHs in the study area. The result of this study indicates the high impact of anthropogenic activities on the contamination of the study area with PAH compounds. Thus, appropriate soil remediation (especially bioremediation) approaches should be considered.

Nowadays, the coronavirus disease (Covid-19) outbreak has become a special and important problem in human societies. Unfortunately, this disease has led to extensive damage and injuries. This study aimed to investigate and compare the feedback obtained from the level of preventive behaviors of Iranians from getting Covid-19 in 1399 and 1400.

In the present descriptive cross-sectional study, a total of 744 participants in the years 1399 and 1400 were included in the study by available sampling method. The data collection tool was an electronic questionnaire that was made available to users via the Internet. To describe the quantitative data, the findings were expressed as Mean ± SD, and frequency was used to describe the qualitative data. Data were recorded and analyzed using Excel software version 2016.

In this study, individuals stated that in 1400, they observed personal and public health to an average (18%) and less (21%). But in the study of 1399, the rate of people who have observed moderate and less personal and public health has been about 8% and 13%, respectively. Also, the number of referrals to the bank in 1400 compared to 1399 has increased significantly. In general, observance of other preventive behaviors such as observing social distance, regular washing of hands, and not holding parties and ceremonies has decreased compared to 1399.

The results of the research findings can provide useful information for formulating policies and guidelines of the Iranian health system to show the state of preventive behavior of the general public. In general, the study indicates that people in the community in 1400 have followed the health instructions to a lesser extent than in 1399. It can be said that this important issue is rooted in people facing environmental stressors, long-term anxiety, and indifference to emerging phenomena.

Due to the Covid19 Pandemic and its impact on the environment from different dimensions, aim of this study was to identify and prioritize the educational needs of students of Payame Noor University in the center of South Tehran in order to achieve university green management during the Pandemic.

the study is practical, cross-sectional and data collection method was descriptive-survey. The statistical population of the study was students of Payame Noor University in the center of South Tehran with 7160 in the year 2020-2021 and the sample size was calculated with Cochran relation with 365 people. the sampling method is stratified and random. Educational needs were extracted by documentary method and were provided to students in the form of a questionnaire. The face validity, content and structure and reliability of it were examined and Friedman test was used to prioritize the indicators of each category.

70% of the study population is female, 30% are male, 57% are undergraduate, 39% postgraduate and 4% doctoral students. The priority of educational needs in three areas of knowledge, attitude and behavior were examined, the educational needs of students in the direction of green management in the field of attitude with an average rating of 2.34 is in the first place.

In all three areas of knowledge, the first priority was to maintain distance with other students and not to gather, especially in roofed places and, utilizing the identified priorities, the necessary proposals were presented in each area.