ABSTRACT
Background: bromide is found naturally in groundwater and surface water. The rapid growth of industrial activities, drainage of surface runoff, and use of methyl bromide in pesticides has increased bromide discharge to the environment. Disinfection of water-containing bromide causes the creation of additional products of organo-halogenated that are considered cancer-causing agents. In this study, the effect and optimization of factors in removal of this ion was evaluated by using the nano-photocatalytic UV/ZnO process
Methods: this analytical study was conducted in a batch system by the phenol-red method. The test design was performed through the analysis model of multi-factor variance with 99 subjects, while the main, interactive, and reciprocal effects of variables, such as reaction time, catalyst concentration, bromide concentration, and pH at different levels of each factor, were analysed by using SPSS version 16
Results: the main, interactive, and reciprocal effects of factors were significant in three different levels with P < 0.001, and the optimal level of the factors reaction time, catalyst concentration, bromide concentration, and pH were 120 minutes, 0.5, 0.1, and 7 mg/L, respectively, by using the Schaffer test. The highest removal efficiency of 95% was obtained at least 91.56 and a maximum of 94.76% was obtained under optimal conditions of all factors
Conclusion: the results show that by optimization of factors, this process can be effectively used to remove bromide from aquatic environments
ABSTRACT
Background: Given that the share of imported rice from India and Pakistan, the current study was conducted to determine the concentration of lead, arsenic and cadmium in the rice imported from the two mentioned countries in comparison to Iranian rice
Methods: This cross-sectional study was conducted in 2014 in Bandar Abbas, using a completely randomized block design. Five samples of each brand [India,Pakistan and Iran] and a total of 75 samples were selected. To measure the amount of arsenic in them, atomic spectrum poll and to determine the amount of lead and cadmium, the graphite furnace atomic absorption spectrometer optical-compliant were used. To analyze the data, we applied descriptive statistics and analysis of variance using SPSS software
Results: The mean of Cd, As and Pb were 0.045, 0.057, and 0.022 mg/kg, respectively. There was a significant difference for Cd in the local and imported rice [P=0.002]. Difference for As in the local and imported rice was not significant [P=0.218]. A statistically significant difference was found between the imported and Iranian rice [P=0.354]. There were no significant differences among all the measured heavy metals in the tested samples of India and Pakistan rice, both legally and illegally [P=0.144]
Conclusion: It was found that the rice was contaminated with heavy elements; it is recommended that measures should be taken to promote healthy rice production, including periodic monitoring of heavy metals in the water and rice seeds, establishing an appropriate operating system to reduce heavy metal emissions, using international experiences on the effects and complications of heavy metals in water resources and farming, and performing quality control measures on the imported rice
ABSTRACT
Background: Traffic noise is one of the major sources of environmental pollution that can cause permanent or temporary loss of hearing in drivers. The purpose of this study was to estimate the prevalence of hearing loss among professional long-distance drivers in Bandar Abbas freight terminal
Methods: One thousand long distance occupational drivers in Bandar Abbas freight terminal not certified by underlying medical conditions were selected for this study. The demographic background, experience, type and kind of vehicles were recorded in a check list. Audiometry test was done at 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz using Welton 1300 audiometer equipped with AD-19 supra-aural earphones. Statistical analysis was done using analysis of variance [ANOVA]
Results: The age, experience, vehicle kind and weight of drivers were 34.02 +/- 13.19, 8.21 +/- 7.84, and 8.73 +/- 6.12 years and 68.30 +/- 15.61 kg. Approximately 52% of drivers studied had a degree of hearing loss. The most common type of hearing loss was sensorineural with mild loss of 69% and 70.9% for the left and right ears, respectively
Conclusion: Periodic medical examination with emphasis on the audiometry can be a way of diagnosing hearing loss in the drivers In addition to providing training courses for the drivers on hearing protection, the use of ear muffs equipment in the truck noise can also be considered as a solution
ABSTRACT
Background: Cadmium [Cd] is a heavy metal that is widely utilized in industries and contaminates soil and groundwater. There are several environmental problems related to cadmium, therefore, the technical and economic methods of removing Cd are of great importance. So this study was conducted to evaluate the efficiency of a type of plant to remove the Cd from aqueous environments
Methods: In this cross-sectional study, the adsorption of Cd examined from synthetic aqueous solutions was evaluated using the seed powder of Miracle tree [Moringa oleifera]. In this order, 70 samples were prepared and tested. To determine the absorption of metals by this sorbent, different pH [5, 7 and 9], sorbent dose [1.5, 3 and 5 g], temperature [20, 30 and 45 degree C], concentrations of Cd [2, 5, 10 and 20 ppm] and exposure time [0, 30, 60, 120, 180 and 210, 240 minutes until reaching equilibrium] were experimented upon, using atomic absorption spectrometer [Varian-AA240FS], and the residual concentration of Cd was read
Results: The highest removal efficiency of Cd under optimum condition [180 minutes and pH of 5] was 70%. The optimum sorbent dose was 1.5 g, which achieved a removal efficiency of 75%. The removal trend was an inverse of Cd concentration. The adsorption of Cd using M. oleifera fitted into both models [Freundlich and Langmuir], but was somewhat better fitted with the Freundlich model and followed pseudo second order kinetics
Conclusion: The results indicated that under optimized absorption conditions [pH: 5, sorbent: 1.5 g, temperature of 45 degree C, Cd concentration of 2 ppm and exposure time of 180 minutes], the removal rate of Cd was 80% and thus the nature of the adsorption reaction was endothermic. Based on the results obtained, the studied sorbent could be introduced as a practical sorbent to the Industrial society. In some sorbents, for M. oleifera, the adsorption capacity was determined based on the results obtained, and the adsorption capacity was found to be 0.1 mg/g. This means that, in order to remove any pollutant [in this case Cd], 10 times of the sorbent weight need to be added
ABSTRACT
Background: Pre-chlorination of raw water containing natural organic matters may lead to forming harmful disinfection by-products such as trihalomethanes [THMs], the measurement of which needs expensive advanced analytical instruments. This study was conducted to anticipate THMs formation potential in Bandar Abbas drinking water system using cheap and simple experiments and a mathematical model
Methods: In a 24 week sampling program, 96 samples were collected weekly from raw water [RW], clarification [CE], filtration [FE], and disinfection effluent [DE]. After measuring the Dissolved Organic Carbon [DOC], residual chlorine, contact time, temperature and pH of water, THMs concentration was calculated using a mathematical model
Results: The means of DOC concentration in RW, CE, FE and DE were 5.56, 4.21, 3.50, and 3.01 [mg/l], respectively. The mean of temperature values varied from 22.28 in RW to 21.25 in DE and the mean of pH variations was measured from 6.75 in DE to 8.37 in CE. Also, the mean of residual chlorine concentration was 0.0 to 1.72 in RW and DE, respectively
Conclusion: The means of calculated THMs were 37.92 +/- 4.82microg/l, 51.15 +/- 9.44microg/l, and 52.71 +/- 8.37microg/l for CE, FE, and DE respectively; this did not meet the related EPA standard [30-40microg/l]; therefore, further detailed studies should be conducted to resolve the consumers' concerns in this regard
ABSTRACT
Background: This study aimed to determine the efficiency of the intermittent cycle extended aeration system [ICEAS] and the removal conditions of treating contaminants, especially nitrogen phosphorus from sea shopping center wastewater
Methods: Experiment was carried out on fish distribution center of Bandar Abbas and 30 samples were collected in a 6 month period from the inlet of the market septic tank. The used pilot study carried out consisted of two zones: pre-react and main react zones. They were divided using a baffle wall. Firstly, wastewater enters a pre-react zone and then through the opening at the bottom of the baffle wall it enters the main react zone. The experiment was carried out with three simultaneous cycles per day
Results: The results showed that the mean of BOD5, COD, phosphorus, and nitrate and nitrite removal was 91.5, 86.7, 59.5, 49, and 80.8 percent, respectively
Conclusion: It was shown that the system is able to remove nitrogen and phosphorus almost similar to other proprietary phosphorus removal processes and with lower cost; however, it is not a proprietary process