Journal of Environmental Health and Sustainable Development
Volume:3 Issue: 3, Sep 2018

The use of arsenic contaminated water can cause a variety of adverse health effects in humans. Therefore, it is essential to seek out a method to remove arsenic more efficiently. This study examined the amount of arsenic oxidation by response surface methodology (RSM) based on Box-Bencken design. In this study, oxidizing arsenite to arsenate was performed by activation of persulfate with UV and the optimal conditions determined using the RSM based on Box-Bencken design to evaluate the effects of independent variables on the response (arsenite oxidation efficiency) performance and to predict the best response rate. In this study, the effects of different parameters such as pH (3-11), concentration of persulfate (4-14 mM), and initial concentration of arsenic (0.1-0.9 mg/l) on process efficiency were investigated. The number of tests in this study was 45, and the oxidation rate was measured using the UV visible spectrophotometer (DR 6000) and the molybdate colorimetric method. Increasing the concentration of arsenic increased oxidation. However, with increasing pH, the oxidation rate decreased and the highest oxidation rate at all concentrations was observed at pH 3. The value higher than R2 (0.934) indicated that the oxidation of arsenic (v) could be determined by this model. Arsenite is a highly toxic metal that is difficult to remove by conventional treatment methods, but a pre-treatment phase can convert arsenite into arsenate and facilitate the removal process. In this study, the use of UV-activated persulfate increased the efficiency of arsenic oxidation to 96%.

Environmental behavior helps to minimize environmental damage and increase the environmental benefits and advantages. The present study aimed to determine the environmental behaviors of students in Jahrom University of Medical Sciences. This cross-sectional study was conducted on 285 students in the academic year 2016-2017 by the stratified sampling method. The data collection tool was a standard questionnaire. The data were analyzed by SPSS 16 software and using descriptive statistics, independent t-test, one way ANOVA, and Pearson correlation coefficient at significant level of α = 0.05. The study participants included 66.3% female and 33.3% male with an average age of 21.41 ± 20.40 years. Among the students, 36.14% had a weak environmental knowledge, 53.34% intermediate knowledge and 10.52% high level of environmental knowledge respectively. The largest source of environmental information was television, internet, and social networks. The students’ knowledge, attitude, and behavior was at a moderately upward level and there was a significant difference between girls and boys regarding environmental behaviors (p < 0.05). There was a weak significant correlation between environmental attitudes and environmental behaviors (r = 0.39)
(p < 0.001). However, there was no significant correlation between environmental knowledge and environmental behavior (r = 0.69, p = 0.25). The environmental behavior of students in Jahrom University of Medical Sciences was relatively good, among which energy consumption behavior was the highest and waste recycling behavior was the lowest. Therefore, it can be concluded that having environmental knowledge cannot be a guarantee of environmental behavior.

Application of point-of-use (POU) drinking water treatment units is expanding across the world due to the increased concerns about the adverse health effects of water pollution. The main treatment systems of these devices are mostly activated carbon and nano-filter or reverse osmosis. This study was conducted to evaluate the effect of using POU units on physical and chemical characteristics of water supply by people of Tabriz. The results were compared with national drinking water standards of Iran. A total of 60 samples were collected from 30 devices and analyzed for physical and chemical parameters especially heavy metals. According to the findings, the physical and chemical parameters of the treated water were acceptable. Concentration of Pb was significantly higher than standards in the input water and effluent obtained from units. Although drinking water plays an indirect role in providing minerals for the body, consumers of these devices should be made aware of the reduced intake of minerals through drinking water. Considering the efficiency of household POU drinking water treatment units to reduce heavy metals that have health effects on humans, adequate supervision should be performed on the supply of standard and suitable products in the market.

Hospitals are one of the main water consumers in urbane area. Due to lack of enough information, the challenges and some of the solutions were investigated for optimization of water management. This study was a cross-sectional study in a Shiraz educational hospital. Data were collected by questionnaires with 146 items. The items was classified in several steps; (1) determination of present situation; (2) identification of challenges in water management; (3) identification of opportunities for reducing water consumption; (4) writing several practical scenarios; (5) cost-benefits analysis for each scenarios; (6) providing the results to the hospital for decision-making. Scenarios were including: installation of a bottle 1.5 litters in toilet flushing, substitution of water cooling with mixture ventilation system (natural and artificial air conditioning system), reuse of regeneration water from cation exchanger, substitution of flooding irrigation with dropping system, using the native or adaptable plants with dry climate. According to the results, 48488 m3/month water was required; however, it was 431125 and 12491500 m3/month in winter and summer (present situation). The cost-benefit of scenario 1,2,3,4 and 5 were 960,170,2370000,13500 and 7500 USD, respectively. Moreover, the investment repayment were 4 years, 1 month, 3.06 years, lower than 1 month, and 3.8 years, respectively. Water consumption was 8-200 times higher than really water demand. It could be result of traditional distribution system and improper management. The scenario 4 was the best alternative for this hospital. Since the cost-benefit ratio to investment repayment period was higher than others.

There are different methods for removal of cadmium from aqueous solutions. Adsorption based methods are among the bests. One of the most important aspects for adsorption techniques is the availability of an accessible and economical adsorbent. This study aims to investigate cadmium removal from aqueous solutions by walnuts shell waste. Walnut Shell (WS) was used as a carbon and was activated by a chemical agent. The surface characteristics of the synthesized Activated Carbon (AC), kinetic and isothermic variation were investigated under laboratory conditions. The results showed that adsorption could be affected by the amount of adsorbent and pH. The adsorption of cadmium was in the maximum level when pH was 6. Between two investigated adsorption isotherms, Langmuir (R2=0.98) and Freundlich (R2 = 0.97) isotherms well described the cadmium adsorption on walnut shell produced activated carbon. Walnut shell as an agricultural waste can be synthesized into a suitable absorbent to absorb the toxic metal cadmium from aquatic solutions.

Chlorpyrifos is an organophosphorus pesticide that is commonly used in agriculture. This toxin is harmful to a wide range of organisms, including living organisms, useful arthropods, fish, birds, humans, animals, and plants. There are many physical, chemical, and biological methods for the removal of organophosphorus pesticides from ecosystems, among which biodegradation is preferable because of environmental compatibility and cost-effectiveness. Identifying the effective genes and enzymes in the specific functional groups of pesticides and understanding the kinetics of biodegradation is essential for successful biorefining. This study was a narrative review article. For this purpose, relevant studies indexed in a variety of databases such as Google Scholar, Elsevier, Scopus, Science Direct, Magiran, and SID which published between 2004 and 2018 were retrieved using the key words Bioremediation, chlorpyrifos, Dursban, and microorganism. Finally, a total of 51 articles were studied. The major processes of chlorpyrifos destruction are evaporation, photolysis, chemical hydrolysis, and microbial degradation. Biodegradation is an environmentally friendly and highly efficient process that can be used as an alternative to chemical and physical methods. In this process, the microbial population is used to convert complex toxic compounds into less toxic ones. Chlorpyrifos, which was previously thought to be resistant to advanced biodegradability, has currently shown to undergo advanced biodegradation by bacterial and fungal species. In the future, studies of genes that are highly capable of biodegradation will lead to a complete degradation method that is involved in the microbial destruction of this toxin.