فصلنامه پژوهش در بهداشت محیط
سال پنجم شماره 1 (بهار 1398)

Environmental problems caused by arrival of antibiotics in water resources due to toxicity and lasting effects are a serious threat. This study has been aimed to evaluate the efficiency of granular activated carbon as adsorbent for the removal of Cephalexin from aqueous solutions. This study was performed at laboratory scale and batch system. The influence of process variables such as pH of solution, adsorbent dosage, initial Cephalexin concentration and contact time were Investigated. Equilibrium study data were modeled using Langmuir, Freundlich and Temkin, moreover, kinetic studies were done by models of pseudo first order and pseudo second order. This research found that the Cephalexin adsorption efficiency decreased by increasing pH from 2 to 14, so that after 3 hours, the adsorption efficiency at the 20 mg.L-1 initial Cephalexin concentration and 0.2 g adsorbent, obtained 92.812%, 90.525% and 41.394% at pH 2, 3.5 and 14, respectively. The adsorption of Cephalexin was compatible with Langmuir isotherm and pseudo second order kinetic. Discussion and The present study showed that the granular activated carbon has high potential for adsorption and separation of Cephalexin and such pollutants from aqueous solutions, in addition to features like simple and rapid separation.

Heavy metals can be serious threat to food security because of the ability to accumulte in the body of fish. Therefore, considering the important role of fish play in human nutrition, the concentration of heavy metals, especially in the edible part of the fish, is necessary. In order to investigate the concentration of heavy metals mercury, lead and cadmium in muscle tissue of three fish species, Tuna )Scomberomoruscommerson(, Tap)Thunnustonggol (and tilapia due (Oreochromisniloticus) 20 pieces of fish were randomly collected from fish sailes in Jiroft city in winter 2017. samples were prepared by acid digestion. Data analysis was performed using SPSS 19 software, ANOVA and t-test. The presence or absence of significant difference was determined at 5% level (P <0.05). The results showed that there is a significant difference between the accumulation of lead and cadmium in Tuna, Tap and tilapia muscle tissue (p <0/05) and the rate of lead accumulation in the tuna The concentration of mercury in the fish muscle tissue was lower than the global standard but the two metals of cadmium and lead in the tissues of Tilapia and tap were higher than the global standard. Key words: Jiroft, Cadmium, Heavy metals, food chain.

Using plants to monitor contamination is a suitable method. In this regard, biomonitoring is one of the inexpensive and easy ways to evaluate the quality of air and soil. Considering the problem of contamination of metals such as chromium, cadmium, nickel and lead in the industrial city of Arak, which is reported by researchers, it is likely that these pollutants will be highly absorbed by existing greenhouse plants. Therefore in this study, the amount of heavy metals contamination in mulberry trees (Morus alba) was investigated in different site of the Arak city during the months of May to June 2012. The amount of 13 elements was measured in the fruit and leaf organs of the Morus alba var. pendula and Morus alba with three replications in the landscapes of the Arak city. The map of distribution of heavy metals concentration in fruit and leaf separately in each individual case was carried out using Inverse Distance Weighted method in GIS environment. Based on the comparison of the limitations of metals in food products and the amount of metals found in fruits of berry trees in Arak areas, the berries were high and unauthorized due to contamination of aluminum (29 mg l-1), cadmium (0.66 mg l-1) and lead (1.3 mg l-1). Metal pollution contamination mapping showed that the distribution of most metal contaminants is outside the industrial zone and there is more accumulation in the central regions. Probably, the dispersion of heavy metal particles from industrial sites has led to an increase in the concentration of metals in these areas. Therefore, due to the contamination of the mulberry fruit of these heavy metals, there is a serious warning about the consumption of this fruit, especially in the city of Arak.

Dust modeling can be considered as an appropriate tool for predicting future industrial dust and identifying pollutant emission control strategies. Perceptron (MLP) and radial base (RBF) neural networks were used as a means for predicting the outflow dust from the main cogeneration of Sabzevar cement factory located in Khorasan Razavi Province. the concentration of dust from the main cement chimney in the study area was measured through field measurements. Then, the parameters of the production line (temperature, speed of gas output, voltage, fuel, raw materials, and time of sampling) were used as input data to the nerve networks to predict the concentration of dust. The values obtained from the implementation of the models were compared with the results of field measurements as a superior model selection. The analysis of figures and statistical parameters showed that the mean squared errors for the two MLP and RBF models were as much as 1.787 and 21.263, respectively, and the correlation coefficients were as much as 0.99693 and 0.95811, respectively, which indicates a lower error and greater correlation between the MLP and RBF model in predicting the concentration of dust. Because of the high ability of perceptron nervous networks to predict dust concentration, this model can be a convenient and fast solution to predict the amount of dust in the industry.

Carbon monoxide is a toxic gas and since it is colorless, odorless and tasteless, it often has no warning signs for people who are at risk of this pollutant. This study focused on the spatial distribution of carbon monoxide on a monthly basis with the interpolation method in Mashhad city. In this study, data were collected from 19 metropolitan stations in the city. Then the inverse weighing intervals, ordinary kriging, and universal kriging methods were used. To determine the best spetial distribution, the root mean square error were applied .finally, the best interpolation methods was selected.with the help of geostatistical map in Arc GIS, monthly zoning map have prepared during 2017-2018. The results showed that ordinary kriging is a best method rather than universal kriging and inverse weighteing due to the lees error. By providing monthly zoning map in 2017-2018, it was cleared that in the months of April, May and June, the middle belt of the city was more polluted from northwest to southeast. The estern part of city in July, August and September have been more contaminated rather than other area. The months of October, November and December wre more polluted in central part of the urban area and from the western to southwestern of the city, in December, February and March, were indicated more pollution. A mong the metropolitan stations for measuring air pollution, southern part of Khayam and sadaf had a highest levels of carbon monoxide and Khaghani and Elahie were lowest rate. Also, monthly zoning maps indicated that the highest pollution rate in hot season was in the eastern and in cold season was in the western part of the city. However, the amount of carbon monoxide was less than standard level during 2017-2018.

Perfectly clean air cannot be found in nature. It contains a certain abundance of particles, including dust, dirt, soot, smoke, and liquid droplets. Mounting evidence indicates increase in particle concentrations and health effects attributed to them in developing countries. In this work, we focused on the determination of number of cardiovascular, respiratory diseases and total death associated with PM2.5 in Karaj city during 2012 to 2015. The health effects of PM2.5 concentrations in ambient air of Karaj was determined using AirQ+ software. Air pollution data was obtained from the Department of Environmental Protection of this city. To validate the data, WHO criterion was performed. After all, data processed by Excel was given to the model. The annual average PM2.5 concentrations in ambient air of this city during the study was higher than WHO health protective guideline (10 µg m–3). The concentration of pollutant has been reduced during the study period but there is a sudden increase in 2015. In addition, the most attributable proportion was estimated in Karaj in 2012 (59.04% for long-term and 5.86 for short-term effects). PM2.5 exposure has caused 275 and 60 natural deaths due to long-term and short-term exposure in 2012 which is unexpected. Regarding the health effects of PM2.5 in ambient air of Karaj city, the importance of controlling air pollution in this metropolis is becoming increasingly evident.

Background and Various factors are involved in proper waste management. One of the most important and effective components is the scientific and specialized capability of experts and managers working in the waste management field. This research was conducted to investigate the education level and specialty of managers and experts of waste management in cities of Iran. In order to conduct this research, a special checklist was developed and sent to waste management organizations in 31 provinces of Iran in an official letter. Data were collected from 15 waste management organizations of different provinces of Iran and they were analyzed using SPSS software. The research results revealed that there are about 29 unrelated fields of education, 6 semi-related fields of education, and 2 completely related fields of education) including environmental health engineering and environmental engineering( at various positions in waste management organizations. Only 8.14% of managers and experts had a specialty in completely related fields of study and 33.22% of them were graduates of semi-related fields of study and 58.64% of them graduates of completely unrelated fields of study, working in waste management organizations in the studied provinces. Based on the research results and also Clause 28 of Waste Management Legislation, reviewing and modifying the process of personnel recruitment and using managers and experts with a relevant specialty in waste management organizations as one of the most effective factors in enhancing the current undesirable condition of waste management seems to be essential.