ARCHIVE OF HYGIENE SCIENCES
Year:2013 | Volume:2 | Issue:1|Papers Count:5

Background & Aims of the Study: Extended-spectrum beta-Lactamases (ESBLs) represent a major group of beta-lactamases which are responsible for resistance to oxyiminocephalosporins and aztreonam and currently being identified in large numbers throughout the world. The objective of this study was to characterize ESBL producers among nonfermenter gram-negative bacteria isolated from burnt patients.Materials & Methods: During April to July 2012, 75 non-fermenter gram-negative bacilli were isolated from 240 bacterial cultures collected from wounds of burnt patients admitted to the Burn Unit at Shahid Motahari Hospital (Tehran, Iran). Bacterial isolation and identification was done using standard methods. Antimicrobial susceptibility testing was performed by disk diffusion method for all strains against selected antibiotics and minimum inhibitory concentration was determined by microdilution test. The ability to produce ESBL was detected through double disk synergy test among candidate strains.Results: Of 75 non-fermenter isolates, 47 Pseudomonas aeruginosa and 28 Acinetobacter baumanniiwere identified. The resistance of P. aeruginosa isolates to tested antibiotics in antibiogram test were 100% to cefpodoxime, 82.98% to ceftriaxone, 78.73% to imipenem, 75% to meropenem, 72.72% to gentamicin, 69.23% to ciprofloxacin and aztreonam, 67.57% to cefepime, 65.95% to ceftazidime, and 61.53% to piperacillin. The results for Acinetobacter baumanniiwere 100% to ceftazidime, cefepime, ciprofloxacin, imipenem, meropenem, cefpodoxime, and cefotaxim, 96.85% to gentamicin, 89.65% to ceftriaxone, 65.51% to aztreonam, and 40% to piperacillin. Double disk synergy test showed that 21 (28%) of non-fermenter isolates were ESBL producer.Conclusions: None of the third or fourth generation of cephalosporins is suitable for treatment ofPseudomonas aeruginosa and Acinetobacter baumannii isolated from burnt patients.

Background & Aims of the Study: Discharge of textile industry colored wastewater without enough treatment into natural water resources cause serious pollution. Most of the conventional wastewater treatment methods are not effective enough to remove these dyes from wastewater. In this study, efficiency of electrocoagulation process with iron electrodes for treatment of Reactive Yellow 14 dye from synthetic solution has been studied and concluded.Materials & Methods: This experiment was conducted in a batch system with a volume of 2 L that had been equipped with 4 iron electrodes. The effect of operating parameters, such as voltage, time of reaction, initial dye concentration, and interelectrode distance on the dye removal efficiency was investigated.Results: In optimum condition (pH 2, voltage 40 V, electrolysis time 25 min, and interelectrode distance 1 cm), electrocoagulation method was able to remove 99.27% of Reactive Yellow 14 from synthetic solution.Conclusions: Electrocoagulation process by iron electrode is an efficient method for removal of reactive dyes from colored solution.

Background & Aims of the Study: The wastewater created as a result of stone cutting industries enters some pools for re-consumption so that its suspended solids settle by gravity. By taking to account the high volume of water and sludge, treatment of wastewater and removal of sludge cause many problems for stone cutting units. The objective of this study was to determine the quality of wastewater and to investigate the effects of coagulants on suspended solids removal efficiency from wastewater of some stone cutting industries (Qom, Iran).Materials & Methods: In this experimental study, the effects of different doses of coagulants including Alum, poly aluminum chloride, Polymer, Ferric chloride (Fecl3) and Lime on Turbidity, “total suspended solids” (TSS) and “total solids” (TS) removal were investigated by Jar Test. Removal efficiency of different coagulates was estimated.Results: The results indicated that lime in dose 100 PPM is the best coagulant for turbidity removal and the highest efficiency for TS removal is related to using Alum in dose 100 PPM.Conclusions: Considering the findings of this study, it can be concluded that using coagulants causes reduction in settling time and speeds up the return of water to the consumption cycle of stone cutting factories, and also increases turbidity removal efficiency.

Background & Aims of the Study: Pharmaceuticals are considered as an emerging environmental problem due to their continuous discharge and persistence to the aquatic ecosystem even at low concentrations. The purpose of this research was the investigation of advanced oxidation processes (Fenton and Fenton-like) efficiency for the removal of nonbeta lactam Antibiotics of azithromycin and clarithromycin from synthetic wastewater.Materials & Methods: In this laboratory scale study, samples of synthetic wastewater were prepared from azithromycin and clarithromycin antibiotics. Concentration of samples was 200 mg/L. Chemical oxygen demand (COD) index was selected as the parameter for evaluation in this study. Fenton and Fenton-like oxidation processes were done on synthetic wastewater of azithromycin and clarithromycin. In Fenton (Fe2+/H2O2) and Fenton-like (Feo/H2O2) processes the influence of pH, iron and hydrogen peroxide on the removal efficiency of the antibiotics were studied and the optimum values for each parameter were determined.Results: The optimum condition for Fenton in removal of azithromycin and clarithromycin were pH=7 and 7, Fe2+0.45 mmol/L and 0.45 mmol/L, hydrogen peroxide 0.16 mmol/L and 0.2 mmol/L, and contact time of 1 h and 1 h, respectively. The optimum condition for Fenton-like in removal of clarithromycin and azithromycin were pH=7 and 7, Feo 0.3 mmol/L and 0.36 mmol/L, hydrogen peroxide 0.3 mmol/L and 0.38 mmol/L, contact time of 30 min and 30 min. Conclusions: The findings of this study demonstrate that the Fenton and Fenton-like processes under optimum conditions can play an important role in the removal of azithromycin and clarithromycin antibiotics from industrial wastewater.

Background & Aims of the Study: The aim of this study was to determine the ecology of malaria vectors in order to select the vector control masseur in the future. This study was carried out on trend of malaria cases and malaria vectors in Saravan county, Sistan & Baluchestan Province, Iran.Materials & Methods: The adult mosquitoes were collected by standard Pyrethrum space spray collection and larvae by dipping method twice a month in 2011 for 12 months.Samples were identified by systematic keys. The 5-year epidemiological data was collected from Malaria Control Centre, Iranian Ministry of Health and Medical Education.Results: Four Anopheles species identified including; An opheles (Cellia) stephensi Liston, Anopheles (Cellia) dthali Patton, An. (Cellia) culicifacies Giles, An. (Cellia) fluviatilis James.Anopheles stephensi was predominant species whereas An. fluviatilis was the lowest species in adult collection. A minimum temperature of larval habitat was 14oC for An.fluviatilis and maximum was 26oC for An. stephensi. Monthly peak activity of An.stephensilarvae found in April and October and in adult form found in May and October.Monthly peak activity of An. culicifacies larvae found in June and September whereas observed in July and November for adults. An. dthali larvae collected more in September and November whereas Adult form found more in July and November. The number of malaria cases between 2007 to 2011 showed the decrease in first 4 years and then increase in the last years.Conclusions: The dominant species was An. stephensi comprised 54.07% of larvae and 49.16% of adults. We suggest studying on biological forms of this species with specific focus on the bordering areas between Iran and Pakistan in the future.