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Showing 27 results for Naddafi
Investigating the Trend of Changes of Organic Carbon, Nitrogen, Phosphorus, and Temperature During Oily Sludge Composting Process
A Koolivand, K Naddafi, R Nabizadeh, A Jonidi Jafari, M Yunesian, K Yaghmaiean, S Naseri,
Volume 9, Issue 3 (12-2016)
Abstract

Background and Objective: The performance of in-vessel composting process, as one of the most effective methods of oily sludge treatment, depends on factors such as nutrients and temperature. Therefore, it is crucial to investigate the trend of changes of these factors. The aim of the present study was to investigate the trend of changes of organic carbon, nitrogen, phosphorus, and temperature during the composting of bottom sludge of crude oil storage tanks.

Materials and Methods: The sludge was mixed with the immature compost at the various ratios of sludge to compost including 1:2, 1:4, 1:6, 1:8, and 1:10 with the initial C/N/P of 100/5/1 and then was composted for a period of 10 weeks. The process of mixing and moisture adjustment of the mixtures was done 3 times a day during the composting period. Sampling and analysis were performed every week for organic carbon, nitrogen, and phosphorus and every day for temperature.

Results: The research indicated that the concentrations of organic carbon, nitrogen, and phosphorus were decreased sharply during the first weeks of the process and then they were decreased gently. At the final stage of the composting, the ratios of C/N and C/P increased from 20:1 and 100:1 to 26:1 and 166:1, respectively. In addition, the temperature of the reactors was kept in the mesophilic range during the process period.

Conclusion: The similar trend of decrease of organic carbon, nitrogen, and phosphorus in the composting reactors is an indication of decreasing the activity of the microorganisms involved in petroleum hydrocarbons degradation.  


Source identification of PM10-bound Polycyclic Aromatic Hydrocarbons (PAHs) of Tehran ambient air in year 2013
K Naddafi, M Yunesian, S Faridi, A Rafiee, S Parmy, Gh Safari, R Nabizadeh Nodehi , K Yaghmaeian, N Rastkari, R Ahmadkhaniha, S Niazi, M Hoseini,
Volume 10, Issue 1 (6-2017)
Abstract

Background and Objective: Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants that are mostly generated during the incomplete combustion. The main objective of this study was to characterize potential sources of PAHs in Tehran.

Materials and Methods:, Samples of PM10 were collected at 10 monitoring stations belonging to Tehran Air Quality Control Company (AQCC) and transferred to laboratory for analysis. Besides, a SKC Flite 2 Air Sampling Pump (SKC, USA) equipped with a sampling head and PM10 size-selective inlet was used at four stations to compare the results obtained by collecting AQCC monitors (AQCCMs) tapes with the standard sampling procedures for assessing the interchangeability of two field sampling methods. The principal component analysis (PCA) and diagnostic ratios were applied to identify emission sources and source contribution.

Results: The average diagnostic ratios of phenanthrene (Phe)/ (Phe+anthracene (Ant)), benzo(a)anthracene (BaA)/ (BaA+chrysene (Chry)), fluorantene(Flu)/ (Flu+pyrene (Py)), and indeno(1,2,3cd) pyrene (IcP)/(IcP+benzo(ghi)perylene (BghiP)) in samples were 0.79, 0.52, 0.43 and 0.38, respectively. These ratios showed that the combustion, especially fossil fuels and motor vehicles, was the main sources of PAHs emission in Tehran. The results of  PCA analysis also indicated that 49, 29 and 22% of PAHs sources in Tehran atmosphere were attributed to gasoline-driven vehicles, diesel vehicles and other sources, respectively.

Conclusion: According to the results, the combustion, especially fossil fuel and motor vehicle, was the main sources of PAHs emission in Tehran.


Investigation of indoor radon concentration in dwellings and public places of Firuzkuh
M Banar, Ar Mesdaghinia, K Naddafi, Ms Hassanvand,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Radon is a radioactive, odorless gas. Radon gas with the emission of alpha radiation and sticking to aerosols in the air can cause lung cancer. This study evaluated the concentration of radon in residential houses and public places in Firuzkuh city and compared the values with the recommended international guidelines.
Materials and Methods: Radon gas concentration was measured by passive measurements using CR-39 detectors. The detectors were placed in houses and schools of the city for three months. After this time, the detectors were located and placed in a 6.25% normal solution at 85 °C for 4 hours in a laboratory. After preparation, using an automatic scan and appropriate statistical method, the concentration of radon gas was determined.
Results: The results indicated that the average concentrations of radon gas in homes and public places were 137.74 and 110.17 Bq/m3, respectively. Comparing the results with the WHO guideline showed that 76.3% of the homes and 66.7% of the sites had a concentration above the guideline (100 Bq/m3).
Conclusion: The results of this study can be used to prepare the National Radon gas map in the country.
 

Measurement of radon concentration in indoor air of residential and public buildings in Nourabad Mammasani city and estimation of its effective dose
H Hassanvand, N Dehghan, K Naddafi, Ms Hassanvand, R Nabizadeh, S Faridi, Z Yousefi,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Radon gas is one of the environmental risk factors which can increase the risk of lung cancer and it is well known as the second-leading cause of lung cancer after smoking. The aim of the present study was to investigate indoor radon gas concentration in residential and public environments of Nourabad Mammasani city and to estimate the effective dose due to radon exposure.
Materials and Methods: In this study, 52 homes and 8 public places were investigated to measure the concentration of indoor radon gas. Indoor radon concentrations were measured using passive sampling approach, alpha-track detectors (CR-39) for three months, and after that, detectors were sent to the laboratory to count the number of tracks.
Results: The results of this research showed that the average radon concentration (± SD) in the homes and public places was 42.4(±14.7) and 32.9(±20.1) Bq/m3, respectively. All radon concentration values were lower than the US Environmental Protection Agency standard and WHO guideline. The average of annual effective dose due to the radon exposure in homes was estimated to be 1.07 mSv. The evaluation of the results showed that there was a significant relationship between the room type and the number of floors with radon concentration in the residential buildings.
Conclusion: The results indicated that the indoor radon concentration as an environmental risk factor in the studied places was lower than the WHO guideline levels. Consequently, the indoor radon is not likely a major environmental risk factor in the studied environments.

Review of studies on air quality status and its health effects in Iran
K Naddafi, Ms Hassanvand, S Faridi,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Air pollution is a leading environmental risk factor on health and it is the major cause of death and disease at global level. Air pollution has been shown to have a significant share in the non-communicable diseases (NCDs) burden. After smoking, it is the second cause of deaths due to NCDs, associated with an increased risk of developing acute and chronic diseases and mortality.
Materials and Methods:  In this study, a review was initially conducted on the basis of indices conducted in the world, the status of ambient air pollution and its effects on health in Iran and other countries, and then the status of ambient air quality and its effects on health in Tehran metropolitan between 2006 and 2017 were shown, based on the results of the studies conducted by the Environmental Research Institute of Tehran University of Medical Sciences.
Results: The results showed that the annual mean of ambient air population-weighted PM2.5 exposure concentration in Iran was about 48 μg/m3, which is relatively lower than its global mean concentration (51 μg/m3). Based on the most recent study (in 2018) about 8.9 (7.5-10.3) million deaths in those aged above 25 years were attributed to exposure to outdoor air PM2.5 in the world. Although there are substantial differences between the results of studies have been done regarding the number of air pollution attributed deaths, numerous studies showed that air pollution is a major cause of death. Results regarding temporal variations of air quality in Tehran that is performed by the Institute for Environmental Research (IER) of Tehran University of Medical Sciences (TUMS), indicated that PM concentration had an increasing trend from 2006 to 2011. The maximum mean concentration of PM2.5 over the past 12 years has occurred in 2011, which was 38 μg/m3. The PM concentration had a decreasing trend from 2012 to 2015, reaching about 30 μg/m3. However, in the years 2016 and 2017, the annual mean PM2.5 concentration in Tehran was increased compared to its corresponding value in 2015. Furthermore, results of this study demonstrated that, in Tehran, not even one day was classified as "good” (AQI=0-50) from 2011 to 2017 based on the air quality index (AQI), but the number of days in which AQI was “moderate” (AQI=51-100) was increased from 2011 to 2015, and the number of days with the AQI of “moderate” reached 80 in 2015, while the rest of the days having an unhealthy air quality. In 2017, AQI was “moderate” in 20 days, “unhealthy for sensitive groups” in 237 days, “unhealthy” in 107 days, and "very unhealthy” in 1 day. The obtained results indicated that about 4878 (3238, 6359( of deaths due to all (natural) causes were attributable to long-term exposure to PM2.5 in Tehran in 2017.
Conclusion: Studies showed that air pollution has a considerable share in the number of attributed deaths. Moreover, there were substantial differences between the results of national and international studies in the burden of disease attributed to air pollution. Therefore, there is a crucial need for accessing to reliable data on air pollution as well as baseline mortality and morbidity in order to study the status of air quality and its effects on health over the country. 

A review of studies on burden of disease attributable to environmental risk factors in Iran: achievements, limitations and future plans
K Naddafi, A Mesdaghinia, M Abtahi, Ms Hassanvand, R Saeedi,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Environmental burden of disease (EBD) studies are one of the most important needs for determining the current situation, increasing the effectiveness of health policies and programs and prioritizing environmental health interventions. This review article was evaluated the status of the EBD in Iran based on the results of the latest Global Burden of Disease (GBD) Study, other international studies and national estimates in the country.
Materials and Methods: In this study, the researches on the EBD in Iran were identified by searching in the international and national scientific databases and the search results were studied and analyzed.
Results: The review of the EBD studies showed that based on the results of the GBD study, the share of environmental risk factors in the total burden of diseases in the country in 2017 according to the disability-adjusted life years (DALYs) and deaths were about 8 and 13%, respectively. According to the results of the GBD study, the contributions of environmental risk factors in the attributable DALYs in the country in 2017 (a total value of 1,648,329) were as follows: ambient air PM2.5 for 45.0%, occupational risk factors for 25.1%, exposure to lead for 19.4%, unsafe water source for 5.0%, tropospheric ozone for 1.7%, lack of access to handwashing facility for 1.5%, unsafe sanitation for 1.4%, residential radon for 0.6%, and household air pollution from solid fuels for 0.3%. The total DALY rate and death rate attributable to solar ultraviolet radiation in Iran in 2000 were estimated to be 46.2 and 0.7, respectively. The DALY and the DALY rate attributable to elevated levels of fluoride in drinking water due to dental fluorosis in the country in 2017 were 3,443 and 4.14, respectively. The evaluation of the effect of water fluoridation as an environmental protective factor showed that the intervention by reducing the risk of dental caries could fall the DALY and DALY rates in the country by 14,971 and 18.73, respectively. In the period of 2005-2017, the DALY rate (per 100,000 people) attributable to ambient air PM2.5, tropospheric ozone, residential radon, and occupational risk factors rose that the result increases the importance of the preventive measures and controls of these risk factors.
Conclusion: There was a considerable difference in the burden of disease attributed to each risk factor in various international studies as well as between national and international studies. The results of national studies on the burden of diseases attributable to environmental risk factors are considered to be more reliable and practical due to the application of more detailed data and conducting subnational evaluations; therefore, the strengthening and continuing these studies at the national and sub-national levels with regard to priorities, needs, and spatiotemporal trends using domestic reliable data and information are necessary and strictly recommended.
 

Assessment of environmental health status of Iran according to the environmental performance index report in 2018
Mansour Shamsipour, Homa Kashani, Masud Yunesian, Kazem Naddafi, Mohammad Sadegh Hassanvand, Reza Saeedi, Mahdi Hadi, Alireza Mesdaghinia,
Volume 13, Issue 2 (8-2020)
Abstract
Background and Objective: In this study, we aimed to assess Iran’s position and trends for environmental health status among the countries of “Iran’s perspective document in 1404” according to the indicators used in Environmental Performance Index (EPI) report in 2018.
Materials and Methods: The score of indicators in environmental health area; air quality (including household solid fuels, exposure to PM2.5, and PM2.5 exceedance), water and sanitation (including drinking water and sanitation) and heavy metals (including lead) were extracted for all studied countries as well as for the last and baseline (generally ten years prior to last report) years from EPI 2018 database. According to EPI scores, the performance of the studied countries in each indicator was ranked. The percent change in the score of each indicator from baseline to current year was calculated and compared with the mean percent change for all studied countries.
Results: Iran ranked 7th regarding air quality in 2016. Also, it ranked 6th, 8th, and 9th in terms of household solid fuels, exposure to PM2.5, and PM2.5 exceedance, respectively. The EPI score for Iran regarding water and sanitation was 54.4 in 2005 and 58.74 in 2016 (percent change=7.98%). Iran ranked 21st in 2005 regarding lead exposure index. Although this index showed a growth of 100% in 2016, which is very desirable compared to the average growth of all countries (34.47%), but only leads to one step up in the ranking of Iran and was ranked 20th in comparison with other countries.
Conclusion: Totally, according to EPI 2018, Iran ranked 6th in the field of environmental health issues among 23 countries of “Iran’s perspective document in 1404”. However, there is uncertainty in the accuracy of the EPI raw data used for calculating index scores. Hence, caution should be exercised in their interpretation.

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