آلاینده ها

Human activities, such as production and consumption, generate waste that pollutes environment. This pollution creates unfavorable conditions for humans and other living beings.  Microorganisms, however, offer potential solutions. These tiny can be both beneficial and harmful to humans. While their negative aspects, like pathogenicity or corrosion, have been exclusively studied, this review focuses on the positive potential of these often-threatened bacteria. Here, we explore their ability to clean and biodegrade environmental pollutants. The review draws on research conducted by the authors and other researchers, examining how bacteria responsible for corrosion can biodegrade and purify various pollutants such as PCP, pesticides, detergents, and even bioplastics. Since the biodegradation pathways for these pollutants have been identified and their safety for living organisms considered, the use of such bacteria for environmental cleaning is recommended.

Despite its great impact on economic progress, the cement industry produces a variety of environmental pollutants, including NOx, carbon dioxide, and carbon monoxide, the release of which can cause serious damage to the environment. In the meantime, the biggest impact of this industry on the environment is related to its burners, and the present research was written with the aim of investigating the effect of the location of calciner burners on reducing the emission of environmental pollutants in Qaen Cement Factory. The research method in the current research is quantitative, and in order to numerically investigate the effect of two positions for calciner burners in the lower part (main position) and in the upper part on the emission of pollutants, was used Ansys Fluent 2022 software. The findings of the research show that the Qaen cement factory in the calciner section is facing the problem of incomplete combustion, which has led to the production of carbon monoxide instead of carbon dioxide. In addition to reducing temperature and increasing fuel consumption, this incomplete combustion causes the production of significant carbon monoxide, which destroys the environment. Also, the results indicate that in the upper burner mode, due to the reduction in the chance of fuel and air mixing, the combustion becomes incomplete and the emission of carbon monoxide increases, but the production of Nox decreases due to the decrease in the combustion temperature.

Pleurotus florida is an edible mushroom with a high potential for removing oil pollutants. In this study, the effect of gas oil on pin creating and amino acids content was investigated. The gas oil concentrations were used 2.5- 10% and for 30 days.The results showed that gas oil has a positive effect on the pinning stage, and increasing its concentration increases the number of pins. Increasing the concentration of gas oil in the treatments reduced the water consumption pattern. The highest consumption of the aqueous phase belonged to the control sample. Seventeen amino acids were evaluated. The study of amino acids showed that the growth of fungi in gas oil-contaminated environments causes a significant increase in the content of amino acids (15 amino acids). The amino acid hydroxyproline was not reported in the selected gas oil treatment sample. According to these findings, P. florida can be considered as a safe species, with fast growth and resistance to petroleum pollutants for simultaneous removal of contaminants and the use of biomass to produce the required amino acids in the industry.

The present study was accomplished to purify and biochemically characterize the phenol-degrading enzyme from the bacteria existed in petroleum-contaminated soils. The catechol 1, 2 dioxygenase was extracted from Aneurinibacillus migulanus Isolate ZNU05 and purified using Q-Sepharose ion exchange chromatography column. The enzyme activity was examined under different pHs (ranged from 4 to 9), at different temperatures (ranged from 20 to 70˚C), in the presence of various metal ions chloride salts (Ca2+, K+, Mn2+, Co2+, Zn2+, Mg2+, Cu2+ and Na+), and with various solvents (ethanol, ethyl acetate, petroleum ether, acetonitrile, N-amyl alcohol, N-hexane, and toluene). In addition, the enzyme activity was investigated using different substrates such as phenol, catechol, benzoic acid, pyrogallol and α-naphtol. SDS-PAGE analysis indicated that there was a single-band protein with a molecular weight of approximately 40 kDa. The catechol 1, 2 dioxygenase had a maximum activity at temperature 30˚C at pH 8.5. Moreover, the catalytic activity of the enzyme was increased in the presence of cobalt and zinc ions as well as organic solvent of amyl alcohol, while it was decreased or inhibited in the presence of the other metal ions and organic solvents used. Among different substrates on enzyme activity, catechol was the most favorable for the enzyme, so that, the Vmax and Km were 8.959 U/mg and 4.992 µg/mL for the substrate, respectively.

The high application of the nanoparticles in industry, health and agriculture increases the possibility of nanoparticles entering the environment, especially the aquatic environment. In the present study, the effects of nano colloidal silver and copper oxide nanoparticles (Cu2ONPs) were investigated on the liver and blood plasma of the Caspian kutum (Rutilus kutum) fry by measuring the activity of the ALT, AST, ALP and LDH enzymes. The samples (17.1±3.6 g) were prepared from the Propagation and Reconstruction Center of Dr. Yousoufpour. After exposing the fish to different concentrations of the nano colloidal silver and Cu2ONPs, the blood was collected on the 7th and 21st days of the experiment. At the same time, the liver tissue of the fish was removed and stored in the -70oC until analyzes of the parameters. The results showed changes in the activity of the enzymes in the liver and plasma of the Caspian kutum fry. The most changes of enzymes were observed in the plasma on the 7th day of the experiment. The LDH enzyme had the most changes in the plasma other than the enzymes. On the 21st day, only the plasma LDH had a significant variation. In the liver, the levels of ALT, AST, ALP and LDH enzymes were almost increased during exposure to the nanoparticles. In the liver, as with plasma, the most changes of the enzymes belonged to the LDH. In conclusion, fluctuations in the metabolic enzymes indicate a change in the physiological state of fish under nanoparticles stress that can threaten aquatic health.

Envirnmental factors such as seasonal winds, together with pollutants, dust and dune sand, reduce the drivers’ visibility, and when settled over the road surfaceproduce a negative impact on the skid resistance of asphalt pavements. In this study, the effect of dust and dune sand on the surface macro texture of road asphalt pavements in several sites, located in the Sistan and Balouchestan Province in Iran, was investigated. For this purpose, five road sections located in the areas with long periods of intense dusty and sandy winds , were monitored over a period of one and half months. In each site, the road surface under consideration was initially cleaned. Then, throughout the monitoring process, the images from these road surfaces were digitally taken and processed using an image processing software. Thereby, the road surface brightness parameter was calculated. Moreover, the macro texture depth of road surface in each site was also measured. The results indicated that there is an adverse relationship with strong correlation between the surface contaminations or brightness with the mean macro texture depth of road surface. The results also indicated that the rate of reduction in the mean road surface texture depth and brightness would reduce with time.

Nano based sensors have sensitivity and specificity to sensors made from other industrial materials. Nanosensors work on a similar scale to natural biological processes. Suitable for use in environments with chemical, biological, and cognitive molecules that make physical changes more recognizable. In this study, we will the rate of methane emissions from coal mines and the monitoring and management of gases with the help of Nanosensors in the Central Mine of Tabas Parvadeh. Improvements in sensitivity have increased the efficiency of nanosensors due to the high surface to volume ratio of nanoscale materials as well as the new physical properties of nano materials. Potential applications for Nanosensors include the detection of workplace pollutants, the environment and the monitoring of production processes, equipment and transportation systems. The intensity of emissions from coal mines depends on the levels of coal and the volume of their gas. The method of coal extracting is effective on the amount of emissions from mines. The prediction of gas emissions from coal mines is based on experimental and computational operations that have yielded acceptable results in this study, which can be considered.

Natural and artificial forests absorb air pollutants and reduce pollution in addition to wood production. This study investigated the role of Polchahr forestation region in Kermanshah was investigated in reducing pollution due to petrochemical industry and also the effect of zinc and chromium on physiological characteristics and growth of Pinus eldarica Medw. and Cupressus Sempervirens L. The plantation area in Petrochemicals factory (infected site) and a plantation area around Petrochemicals (control site) were designated for the study. Results showed that the concentration of the two elements in roots and stems of both species in the infected site were significantly higher than the control site. Also in the area infested with the two elements, the shoot and root lengths of Pinus eldarica Medw. species decreased significantly compared to the control area while in Cupressus sempervirens L. only root length in the contaminated area was significantly difference from the control areas. Moreover, results showed that in the infected area, total chlorophyll, and proline and sugar contents in the leaves of the Pinus eldarica Medw. and Cupressus sempervirens L. species were significantly different compared to the disinfected area. In general, reduction in the pollution with zinc and chromium was more in Pinus eldarica Medw. than in Cupressus sempervirens

1. According to the studies report about the rates of diseases in the world in 2015, air pollution is responsible for 1.5 million deaths in China and 4.2 million people around the world. Despite statistics that compare the amount of Tehran’s pollutants with international standards, the claim is not far from reality that the air pollution is the main environmental problem in Tehran. Millions of people breathed in the most polluted air of Tehran throughout the day and if the growth of pollution sources continued to produce, so this issue can become a humanitarian disaster. The result of fuel consumption in various sectors is to produce the particles and gases that constant exposure against them involves problems and dangerous complications for human health and other living things and this is only part of the adverse effects of air pollution.
2. AIRREX device, Model HG-550 or analyzer of pollutants for the vehicles made of Korea that is one of standard devices by capability to measure the output gases from exhaust of vehicles; is used in the study to measure the pollutants emitted from exhaust of commercial vehicles in an industrial unit. The analyzer displays also the air ratio to fuel and excess air ratio. The instruction for usage the device is that probe of device puts inside the exhaust of vehicle, the device is turned on and after warming, it starts to analyze the output gas. The amount of pollution of output materials is determined based on standards developed by Iranians national standards organization to number ISIR 9181 and standard set by the environmental protection agency under standard of pollution limit for all vehicles according to the standard table of pollution limit for domestic and imported vehicles as follows.
3. As it has been shown, the major emitted pollutants include carbon monoxide and unburned hydrocarbons that have adverse effects to the air pollution and human health and the environment. Most of these gases are emitted from exhaust because of technical fault of vehicles; and the first step to reduce the production of pollutant gases is their timely service and adjustment because the results of most researches reveal the importance of motor adjustment and circular services of vehicles for reduction of amount of air pollution. One of other tools and techniques to reduce the pollutants in the exhaust of vehicles is the use of catalytic converters on the route of vehicles’ exhaust. Catalyst converter is a device that installs in the engine exhaust system and then converts three harmful exhaust compounds from engine (hydrocarbons, carbon monoxide and nitrogen oxides) into harmless compounds by the catalyzers.

Plants exposed to air pollution show returnable and unreturnable biochemical and physiological alterations. So biochemical parameters can provide valuable information about physiological condition of plants that are subjected to air pollution. This study was performed to determine the effects of air pollutants on the amount of proline، protein، calcium and phosphorus in Medicago sativa and Phaseolus vulgaris leaf and root. We also investigated M. sativa and Ph. vulgaris resistance to the air pollution in Arak Oil Refinery area. The plant samples were collected from polluted and non polluted area and the amount of proline، protein، calcium and phosphorus in leaf and root of plants were determined. The results showed that air pollution led to a significant increase of proline in leaf and roots of both M. sativa and Ph. Vulgaris. Air pollution also led to a significant increase of protein concentration in M. sativa (leaf and root)، but a significant decrease of protein concentration in Ph. vulgaris leaf and root. Concentration of calcium in M. sativa leaf and root under air pollution implied a significant increase. However air pollution caused a significant decrease of calcium in Ph. vulgaris root and no significant alteration of calcium rate in Ph. vulgaris root. Air pollution led to a significant increase of phosphorus rate in M. sativa root، but no significant alterations in M. sativa leaf، instead a significant increase of phosphorus rate in Ph. vulgaris leaf and root. In this study، increasing of protein and calcium in M. sativa plant was indicative of its resistance to the air pollution، and changes in biochemical parameters in Ph. vulgaris implied its sensitivity to the air pollution.