Archives of Hygiene Sciences
Volume:2 Issue: 4, Autumn 2013

Background & Aims of the Study: The global consumption of bottled water is growing with substantial growth in sales volumes on every continent. The highest growth rates are occurring in Asia and South America. Biological and chemical monitoring of these waters is necessary. The aim of current study was determination of nitrate concentration in bottled drinking water in Qom, Iran in 2012. A cross-sectional study carried out in Qom, Iran. First of all, 18 most frequent brands of bottled drinking waters were purchased in June 2012 randomly. Then concentration of nitrate was measured according to the spectrophotometric method. In next step, experiment data were analyzed by Excel Software and Pvalue was obtained by statistical calculations. Finally data were comprised with written nitrate concentration on labels and recommended permissible values. The median nitrate concentration was 2.1 mg/L with the minimum 0.8 mg/L and maximum 8.1 mg/L. In 66.7 % of the samples, the measured nitrate concentrations were less than the written nitrate concentrations and in 33.3% of samples, the nitrate concentration was higher. The statistical calculation proved the significant difference between the median of written nitrate concentration on the label and investigated nitrate concentration (Pvalue > 0.05). It be concluded that the measured nitrate concentration in all of the water samples is below the recommended permissible level.

Background & Aims of the Study: Corrosion and scaling are the most common problems of water facilities. Corrosion imposes many financial and health loss on system and consumer respectively, scaling also causes clogging and head loss in network. The purpose of this study is to determine the corrosion and scaling potential of water supply sources of Qom villages. This cross-sectional study was done in 12 months (from 2011-2012). 100 samples were collected to determine pH, total dissolved solids (TDS), temperature, alkalinity, Calcium hardness and residual chlorine, and water corrosion and scaling have been studied by using Langelier, Ryzner, aggressive and Puckorius indexes. The results illustrate that Qom village water according to the Langelier index equals 1.62 (±0.11), according to Rayzner index equals 10.5 (±0.17), based on Aggressive index equals 12.035 (±0.14) and based on Pokurious index equals 9.92 (±0.13) respectively. Comparison of four index’s were showed that Water conditions in all villages of Qom is in corrosive range. According to this study, water supply in Qom village is corrosive, one of the effective ways for solves this problem is pH adjustment by lime

of the Study Irradiation with ultraviolet light (UV) is used for the disinfection of bacterial contaminants in the production of potable water. The main objective of the study was to investigate and model Disinfection By-Products (DBPs) formation due to the UV Irradiation of the Tajan River water under different Irradiation conditions. Water samples were collected throughout September 2011 to August 2013. Transportation of the sample to the laboratory was done on ice in a cooler, and physiochemical analysis was conducted immediately within one day. Dissolved organic carbon (DOC) was determined by a TOC analyzer. Irradiation experiments were conducted in a series of 25 mL glass serum bottles with Teflon septa. The present study adopts an orthogonal design. The design involved irradiation with UV at a UV/DOC ratio of 0.5–3.0 and incubating (headspace-free storage) for 5–25 sec. A 1 mM phosphate buffer maintained the pH at 6, 7, or 8 respectively, and an incubator maintained the temperature (Temp) at 15, 20, or 25 °C respectively. The development of empirical models for DBPs formation used a multivariate regression procedure (stepwise) which applied the SPSS System for Windows (Version 16.0). The results showed that the total DBPs formation ranged between 12.3 and 67.4 mg/l and that control of the levels was primarily due to the reaction time and the dissolved organic carbon level (DOC) in the water. Reaction time and level of DOC concentrations in water exerted a dominant influence on the formation of DBPs during the UV irradiation of water from the Tajan River. The relationships between the measured and predicted values were satisfactory with R2 values ranging from 0.89 (for Octanal)–0.92 (for Formaldehydes). The DOC level in water is the key factor in controlling DBPs formation.

of the Study: The 2, 4, 6-Trichlorophenol (TCP) is a phenolic compound which it can produce adverse effects on human and environment. Therefore, the removal of these compounds is necessary. The aim of this study is the investigation of TCP removal by using Azolla filiculoides biomass. The Azolla biomass was dried in the sunlight, and then it was crushed and sieved to particle sizes in range of 1-2 mm. Next treated with 0.1M HCl for a period of 5h. The Azolla was washed with distilled water and it was used as adsorbent. The effect of operating parameters such as pH, contact time, TCP concentration and adsorbent dose on the TCP removal efficiency was investigated. The residues concentration of TCP was measured by spectrophotometer in λ max of 296 nm. In optimum condition (pH 3, contact time 120 min, adsorbent dose 10 gr/l and TCP concentration 10 ppm), Azolla was able to remove 95% of TCP from aqueous solutions. The equilibrium data follows the Langmuir isotherm and the proper kinetic model is pseudo-second model. Adsorption process by Azolla filiculoides is an efficient method for removal of 2, 4, 6-Trichlorophenol from aqueous solutions.

Background & Aims of the Study: Collection and transportation of municipal solid waste (MSW) for various reasons, especially economic and social are considered as one of the most important elements of the solid waste management system. More than sixty percent of the costs in solid waste management systems in different countries are due to the collection and transportation process including laboring cost, the high price of fuel and machinery and equipments maintenance. This paper aims optimization of solid waste collection routes of Marvdasht, located in Fars province of Iran. This approach consists of several steps. First step includes filed visits, surveys, and interviews with relevant authorities and individuals in the form of questionnaires through which available information about the current route of solid waste are collected. TransCAD, a professional and specialized software for solid waste routing, is then employed for solid waste collection optimization taking into account factors such as shortest path length and time, minimum U-turn and capacity of machinery, etc… The proposed routes were compared to the existing routes for collection of waste considering costs and collection time. According to the results obtained from TransCAD software for the considered case, compared to the current service the total distance and travel time can be decreased up to 16% and 30%, respectively. TransCAD software can perform appropriate routing for solid waste collection, which has the optimized total distance travelled and travel time as did for Marvdasht city.

Background & Aims of the Study: Dyes have significant role in environmental problems, due to their toxic effects on the food chain and sources of water. The purpose of this research was to study the adsorption of acid yellow 36 dye onto pinecone using batch system. This research was performed at laboratory scale and batch system. Equilibrium isotherms were modeled using Langmuir, Freundlich, and D-R models. Also kinetic studies were done by three models of pseudo first order, pseudo second order, and intra-particle diffusion. The maximum adsorption was achieved at pH 5.0, adsorbent dose 0.7 g/l and contact time 20 min. The equilibrium adsorption capacity (mg/g) increased with increasing initial dye concentration. The Langmuir model (R2=0.99) provided the best fit for the experimental data. The adsorption kinetics were studied and best fit was achieved by pseudo- second order model (R2= 0.96). According to the results obtained of equilibrium and kinetic studies on the adsorption of acid yellow 36, pinecone can be a suitable and efficient adsorbent in the removal of yellow acid 36 dye from industrial wastewater.