فصلنامه پژوهش در بهداشت محیط
سال هشتم شماره 3 (پاییز 1401)

BTEX compounds cause adverse effects on the health of employees in various industries, including the oil industry. This study was conducted with the aim of measuring these compounds and their effect on serum lipid parameters of Abadan oil refinery workers.

In this study, 80 workers (40 exposed people from operational units and 40 non-exposed people from administrative departments) were investigated. Sampling and measurement of employees’ respiratory area was done using individual sampling pump and measurement of lipid parameters of employees’ blood was done using commercial kits of Pars Azmoun company.

The obtained results showed that the average concentration of toluene, ethylbenzene and xylene compounds in the respiratory area of the exposed employees was lower than the standard limit, but the average concentration of benzene compound was higher than the recommended standard limit. The results obtained from the comparison of blood serum lipid parameters showed that there is no significant difference between the two groups of exposed and non-exposed employees. The results of Spearman’s test did not find any significant relationship between these parameters and demographic characteristics in the two groups. However, Pearson’s statistical test showed that there is a significant relationship between some blood serum lipid parameters in two groups, and in both groups of employees, the average blood plasma lipid parameter was higher than the normal range.

The results showed that the concentration of benzene compound is higher than the permissible limit of the standards and the effect of benzene on employees should be prevented with adequate engineering and management controls and periodic inspection.

More than 90% of people’s lives are spent indoors and indoor air pollution is the cause of more than 2.2 million deaths annually worldwide. Contrary to popular belief, the dangers of pollutants in enclosed spaces are greater than in open environments. In this study, the ability of the computer models to simulate flow behavior in the interior space of an industrial workshop was investigated to may check the satisfaction of the environmental standards

The flow pattern and flow mixing and dilution were investigated by developing a specific solver in OpenFOAM and comparing the results with the ex[perimental data.

Due to the initial buoyancy, the plume enters from the lower opening with high concentration and after diluting in indoor space, goes out from the roof opening. It is then observed that while there are no openings, the concentration of Carbon Monoxide in the breathing height of workers will reach the dangerous limit of (100 ppm <) in different models.

In this study, the concentration of Carbon Monoxide in the building’s interior space was estimated far higher than the maximum allowable centration mentioned in the standards. Therefore, the high level of pollution concentration in indoor spaces indicates the inadequacy of natural ventilation and the need for mechanical ventilation to could decrease pollution down to the breathing standard of ocupants.

80% of air pollution in urban areas comes from heavy vehicles. The purpose of this study is to investigate the amount of CO2 , CO, HC, NOX pollutants, types of diesel cars and their relationship with the life of the car.

In this study, out of all diesel cars in Mashhad, which is 5861 cars, 425 cars were randomly selected and after recording the year of car production, using OPTIMA7 NDIR five-gas pollutant device in bright engine mode (Engine operation). Sampling was performed continuously (except for the first to the fourth of April) in the period of December 6, 2017 to May 9, 2017 at nine to twelve and fifteen to twenty o’clock and Then, using SPSS software and statistical tests. The relationship between these pollutants and vehicle life was investigated.

According to the amount of sig (p=0/531>0/05) between the life of the car and carbon monoxide, the amount of sig (p=0/571>0/05) between the life of the car and the amount of hydrocarbon, the amount of sig (p=0/153>0/05) between the life of the car and carbon dioxide output and the amount of p=0/290>0/05 (sig) there is no significant relationship between car life and nitrogen oxides. There is an inverse correlation between the car’s year of manufacture and CO2 and NOX pollutants, So that the higher the car’s year of manufacture, the lower the amount of carbon dioxide and nitrogen oxides. And there is a positive correlation between HC and CO pollutants.

The significant level value (sig) between car life and all pollutants is greater than 0.05, so there is no statistically significant relationship between car life and all exhaust gas pollution. Therefore, the amount of air pollution by diesel cars should be reduced by taking correct management methods.

Consumers often think that food is safe when stored in refrigerators at 4°C. However, food can still spoil and cause foodborne illness, which is one of the most important health challenges. The present study was conducted with the aim of investigating bacterial and fungal contamination in domestic refrigerators.

In this study, 30 domestic refrigerators were examined. First, microbial plates including blood agar and Saburo were placed on the refrigerator shelves for one hour. Then the bacterial cultures were incubated for 48 hours at 36°C and the fungal cultures were incubated for 5 days at 28°C and the colonies were counted. Finally, in order to check the level of contamination of the refrigerator surfaces, treated samples were prepared from the surface of the refrigerator shelves using moist sterile swabs.

Based on the results, 100% bacterial contamination and 58% fungal contamination were observed in the air of household refrigerators, and the amount of bacterial and fungal contamination on the surface of domestic refrigerators was 4.7-8.9 and 3.6-7.2 (log CFU/cm2) respectively

As seen in this study, bacteria enter food through unwashed hands, raw foods, leaking packaging, unwashed shelves, refrigerator surfaces, and long-term storage of food in the refrigerator. Therefore, if refrigerators are not maintained properly, they become a place for the growth of microorganisms and directly and indirectly contaminate the refrigerator and food and make people sick.

the investigation of the adsorption of pollutants from aquatic environments with the least number of experiments, is one of the concerns of researchers. In the present study, the aim is to model the adsorption process of acid dye 62 by a metal-organic framework containing aluminum (MIL-53(Al)-NH2).

In this study, MIL-53(Al)-NH2 was synthesized from the raw material of 2-amino terephthalic acid and aluminum nitrate. After examining the effective parameters on dye adsorption, artificial neural network (ANN), multiple linear regression (MLR) and multiple nonlinear regression (MNLR) have been used to predict the amount of dye adsorption.

The results of XRD, FE-SEM and FTIR analyzes indicated the appropriate synthesis of MIL-53(Al)-NH2. The optimal conditions are: pH=2, time 60 minutes, adsorbent dosage 0.02g and temperature 25°C. According to the results, in the comparison between the three used methods, the neural network model has the highest prediction accuracy. The output of this model has the lowest root mean square error (RMSE) and the highest correlation coefficient (CC) with true data in comparison with multiple linear and nonlinear regression models.

According to the results, it can be seen that the MIL-53(Al)-NH2 is an efficient compound and in addition, due to the high efficiency of the artificial neural network model, this model can be used to ensure the results of dye removal and reduce costs by reducing the number of experiments.

Phytoremediation is a new technology for remediation of contaminated soils, this study was conducted to evaluation of efficiency of EDTA, citric acid and salicylic acid chelating agents in phytoremediation enhancing of Amaranthus caudatus and Tagetes patula for elimination of Cr(III) and Cu(II) from contaminated soils in 2018.

After soil pots contaminating by 50 and 100 (mg/kg) K2Cr2O7 and 200 and 400 (mg/kg) CuSO4 salts, and 2.5 (mmol/kg) of EDTA and citric acid (CA) and 2.0 (mmol/kg) of salicylic acid (SA) solution treating, the cultured seedlings were harvested after 60 days. Then, after seedlings digestion, Cr and Cu contents were determined using ICP-OES

Based on the results obtained, the maximum contents of Cr (mg/ kg) in cultivated soil, root and stem samples of A. caudatus were 2.40, 5.18 and 1.86 were found in the SA, EDTA and EDTA treatments, respectively and in T. patula with 2.74, 6.00 and 1.30 were found to be in the SA, EDTA and EDTA treatments, respectively. Also, the maximum contents of Cu (mg/kg) in cultivated soil, root and stem samples of A. caudatus with 6.74, 3.77 and 3.34 were found to be in the SA, SA and EDTA treatments, respectively and in T. patula with 6.65, 3.45 and 9.50 were found to be in the SA, EDTA and EDTA treatments, respectively. On the other hand, translocation (TF) and bioconcentration (BCF) factors of A. caudatus both were greater than 1 in soils with 100 mg/kg added K2Cr2O7 containing CA, which indicates that this species can be known as hyperaccumulator of Cr

In conclusion, concerning to the considerable role of organic acids in soil refining electrokinetic and phytoremediation efficiency enhancing, using of these soil amendment agents is recommended to cleanup of contaminated soil with heavy metals

In this study, heavy metals in the soil around the Zanjan city, by using indicators of pollution, carcinogenic and non-carcinogenic risk and determining the origin by using statistical methods.

In this study, 30 soil samples were taken from a depth of 0-20 cm and analyzed based on the method of acid digestion by induction coupled plasma spectroscopy.

The enrichment factor for zinc and cadmium was in the extreme enrichment category with an average of 42.1 and 34.5, respectively, and the land accumulation index for cadmium was in the high pollution category with an average of 2.8. Spatial changes of the index of pollution load and modified degree of pollution showed that the intensity of pollution increased near the industrial centers and the linear regression between the ecological risk and the median coefficient of the medium effect range (R2=0.903) showed that 76% of the samples They are in the possibility of toxicity. Cadmium had the highest risk in children and adults with an average non-carcinogenic risk index of 2 and 0.5, especially exposed to skin absorption with an average of 0.5. It shows the risk of more cancer diseases. The result of determining the origin and contribution of heavy metals with the help of statistical evaluations showed that lead, zinc and cadmium are the result of human activities and chromium, copper and arsenic are the result of the combination of human and earth-born activities. have gathered in the area

In order to reduce the negative environmental effects of heavy metals in the soil of the study area, measures such as reducing the entry of pollutants into the soil and refining polluted Soil.

COVID-19 can be transmitted directly through respiratory droplets or indirectly through devices that transmit infection. SARS-CoV 2 has been identified on various environmental levels in hospitals and communities.

Sampling was done according to the instructions of the World Health Organization; environmental samples were taken using a swab with an artificial tip and a plastic shaft. In this study, sampling was done during the busy hours of the hospital and the total numbers of samples 48 samples were collected and finally the samples were analyzed by polymerase chain reaction-reverse transcription (RT-PCR) method.

The results showed that within 36 samples of the hospital, 8 samples were positive and in 10 samples of the comprehensive laboratory, two positive samples were reported. Due to the abnormality of the data, the Kruskal-Wallis test was used to compare datasets of different levels such as (plastic, metal, wood, glass, fibers and living body). According to the results, no significant relationship was observed between levels with different genders and the degree of positive tests (P value = 0.341)

Contaminated airborne droplets can be displaced by air currents and deposited on surfaces. Due to the type of surfaces and higher durability of these viruses on these surfaces, the need for regular and daily disinfection before and after shifts, and in case of exposure to virus infection, must be disinfected with appropriate antiviral compounds with the surface. No contamination has been observed on other surfaces such as fabrics and fibers, but due to the spread of this virus, necessary precautions should be taken.