Maryam Sarkhosh; Mostafa Hadei; Sima Nourbakhsh; Hossein Alidadi; Mohammad Pazira; Gholam Reza Farahzad
Abstract
Background and Purpose: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 ...
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Background and Purpose: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.materials and methods: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.result: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. Conclusion: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.
Muhammad Pazira
Abstract
Background and objective: Paper, pulp and cardboard manufacturing industries discharge large amounts of waste which contain a variety of pollutants and paints. These wastes are believed to generate the most environmentally hazardous industrial wastewaters. Biological procedures alone may not suffice ...
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Background and objective: Paper, pulp and cardboard manufacturing industries discharge large amounts of waste which contain a variety of pollutants and paints. These wastes are believed to generate the most environmentally hazardous industrial wastewaters. Biological procedures alone may not suffice the treatment of such wastes due to having a high BOD5/COD ratio. On the other hand, applying costly chemical approaches to remove all these pollutants in a short time often results in the production of large quantities of sludge. Therefore, these industries are obliged to combine both these methods in order to optimize wastewater treatment. Methods: In this experimental study, the sample wastewater was provided from the discharge channel of Pazh cardboard factory located in Tous Industrial Zone of Mashhad, Iran. The wastewater samples were collected from this factory by composite sampling. Coagulation of these samples was accomplished by clay soil as the single coagulant. The optimum pH of the treatment was determined by Jar tests in various pHs (from 4 to 9). Afterwards, the optimum concentration of the coagulant was also verified at the optimum pHof 8 by Jar tests. Results: The optimum dosage and pH of treatment by clay soil wasdetermined to be 75 g/L and 8, respectively. Under optimized conditions, the removal efficiency of COD, BOD5 and TSS was calculated as 47%, 26% and 57%, respectively. In addition, the pH adjustment at 8 resulted in a 60% reduction of clay consumption. Conclusion: According to the results of this study, the coagulation of cardboard wastes by clay soil could be a suitable pretreatment method. This particular material makes it possible to improve the quality of wastewater in subsequent bio treatments in a much less costly way compared to other conventional coagulants or adsorbents. It was also observed that the ratio of BOD5/COD reduced from 4.5 to about 3. Although the clay dosage required for the wastewater treatment is relatively high, this approach could stillbe recommended for the pretreatment of this type of wastewater as well as the wastes produced by similar industries mainly because the overall cost of this treatment is insignificant. Paper Type: Research Article