Iranian Journal of health, safety andenvironment

403-411

Authors: Elham Rahmanpour Salmani, Akram Ghorbanian, Saeid Ahmadzadeh, Maryam Dolatabadi, Nasrin Nemanifar

Release of textile industries waste especially their dying effluent impose a serious pollution on the environment. Reactive dyes are one of the most used dyes which are recalcitrant to conventional treatment processes. In the performed project, the effectiveness of electrocoagulation process was studied on decolorization. RR141 was selected as model dye and treatment process was performed in a simple batch of electrocoagulation (EC) cell using iron electrodes. Central Composite Design (CCD) was used to plan study runs. Experiments were done under 5 levels of various operational parameters at bench scale. Initial concentration of dye was varied among 50 and 500ppm, pH ranging from 4-12; retention time was ranged between 3-30 minutes, 1-3cm was selected as the distance between electrodes, and current intensity studied under the range of 5-30 mA/cm2. EC treatment process of dyestuff wastewater was satisfactory at high levels of current density, pH, and retention time. While increasing the initial dye concentration and electrodes gap had a negative effect on decolorization performance. Determined optimal conditions to treat 200ml of sample were including pH: 9.68, electrode gap: 1.58cm, dye concentration: 180ppm, retention time: 10.82 minutes, and current intensity: 22.76mA/cm2. Successful removal of the model dye about 99.88% was recorded in the mentioned values of variables. Simple design and operation of the experiments can be an interesting option for implementation and applying of inexpensive electrocoagulation treatment process which was successful to reach nearly a complete decolorization.

421-427

Authors: Amir Mohammadi, Mohammad Miri, Afshin Ebrahimi, Hassan Khorsandi, Sepide Nemati

Trihalomethanes (THMs) formation in treated water is a consequence of a reaction between the chlorine used for water disinfection and some natural organic matters. The objectives of the present study were monitoring of THMs concentration in Isfahan (A metropolis city in center of Iran) water distribution network (IWDN), evaluation factors that affect the THMs formation potential and identification of critical points by using geographical information system (GIS). The study was performed in summer months of 2014. For sampling point's selection, city divided into 30 zones and water quality parameters such as pH, Electric Conductivity (EC), residual Chlorine, Total Organic Carbon (TOC) and THMs of IWDN measured. Multi regression analysis was used to estimate the correlation between THMs formation and these variables. While the statistical analysis with Spearman non-parametric correlation coefficients showed a positive correlation between distance from treatment plant and THMs concentration(r=0.45, P =0.01) and negative strong correlation(r=-0.95, p>0.001) between THMs and TOC concentrations, there was no strong significant relationship between THMs formation in IWDN and some variables including pH, temperature and residual Chlorine. The results reveal that the average value of the THMs at sampling points for summer attained 42.56 ppb which was lower than the EPA and WHO standards. It is recommended that the distance from the treatment plant was used as an effective parameter for estimation of THMs formation potential.

434-440

Authors: A. Ansarimoghaddam, M. Davatgar, F. Laal, R. Mirzaei

Technological progress and oil industry development accompanies have a high rate of risk. This study was conducted with the aim of evaluating occupational accidents and related indicators for decreasing the number of damages by offering control measures. In this descriptive-analytical study, essential information was extracted from the records and agendas of the technical safety committee and the evaluation of accident frequency was done based on the accident type, the time and the location of its occurrence, environmental condition, root factors, and demographic variables of the injured. The relationship between repetition, severity, frequency of the accidents and marital status of the company’s personnel was also studied. Accident analysis was done by Chi square test . The occurrence of about 102 accidents was reported in an incident evaluation, which was done between the years 2008 and 2010. The average age of the injured was 29.1± 8.61. Accidents and clashes were 31.4% of the accidents and falling from height 21.6% of them. Many of the accidents occurred in plumbing activities (24.5%), tank construction (23.5%), and civil operations (15.7%). 47% of the accidents happened in 2009, 43% in 2010, and 10% in 2008. Occurrence rate of accidents was 48.1 and their intensity rate equaled 0.15 for one mi llion working hours. The relationship of accident type and marital status was a meaningful relationship based on Chi-square test (P = 0.014); this test showed the relationship of accident type and its reasons a significant one as well. (P = 0.035) Considering the calculated coefficients and evaluated factors in this study, safety training, constant inquiring of sub -activities, inserting safety and HSE provisions and guidelines to the contractors’ contracts and monitoring their application would be effective in decreasing the number accidents. .

445-459

Authors: Maryam Jalili

Aflatoxins (AFs) are cancerous secondary metabolites produced primarily by Aspergillus flavus and Aspergillus parasiticus in agricultural foodstuff such as peanuts, maize grains, cereals, and animal feeds. Food and Agricultural organization (FAO) estimated that as much as 25% of the world’s agricultural commodities are contaminated with mycotoxins, leading to significant economic losses. Moreover, AFs are highly toxic, mutagenic, teratogenic and carcinogenic. Therefore AFs reduction in food and feedstuffs is a major global concern. This review aims to bring up to date the detoxification methods applied for reduction of aflatoxins by physical (cleaning, heating, irradiation, adsorption), chemical (chemical compound, ozonization) and biological (applying bacteria, yeast and nontoxigenic Aspergillus strains) methods in different foods from 2000 to 2015. Papers related to aflatoxin reduction by managing aflatoxins risks, using resistant crops varieties, and good agricultural practices and papers related to other aflatoxins (M1, M2) were excluded.