International Journal of Environmental Health Engineering
Volume:1 Issue: 4, Oct 2012

 This study was designed to evaluate the validity of urinary 1-hydroxypyrene as a biomarker in carcinogenic PAHs (cPAHs) exposed Iranian carbon anode plant workers. 

 The study population consisted of 42 workers working in a carbon anode plant and control group consisted of 43 office workers. Personal air sampling was performed to assess workers atmospheric exposure to carcinogenic PAHs . Urine samples were collected for analysis of urinary 1-hydroxypyrene using high performance liquid chromatography (HPLC). Statistical analysis was performed with SPSS version 16 software. 

 The mean concentration of occupational exposure to cPAHs in the exposed group was 11.42±7.56 ΅g/m 3</sup> . Mean level of urinary 1-hydroxypyrene in the exposed and control groups were 6.32±4.9 and 0.54±.48 ΅mole/mole creatinine, respectively . Urinary level of 1-hydroxypyrene in the exposed group was significantly higher than the control group (P</em><0.001). A strong and significant correlation between total cPAHs exposure and urinary 1-hydroxypyrene (r=0.79, P</em><0.001) was found .

 The results confirm urinary 1-hydroxypyrene level as a good biomarker in cPAHs exposed workers. In addition, considering the level of urinary 1-hydroxypyrene, it can be concluded that studied carbon anode plant workers are exposed to substantial risk of cancer and other genotoxic effects which are the result of cPAHs exposure.

 The aim of this study was the investigation of musculoskeletal disorders risk factors among building demolition workers. 

 Posture, activity, tools, and handling (PATH) method as a work sampling method was applied to record the postures, activities, and handling of building demolition workers in four tasks. The percentage of working time is reported for each item to compare the risk factors in tasks. Nordic musculoskeletal questionnaire also was used to study the prevalence of musculoskeletal disorders over 12 months. 

 Trunk, leg(s), and arm(s) postures differed significantly among tasks. Neutral arm posture and non-neutral leg(s) and trunk postures were observed frequently. Manual materials handling (MMH) activities are distributed differently among tasks. Moving was the most observed (35%) and carrying was the less observed (11.8%) MMH activity. Gross grasp was the most observed (78.5%) hand activity in building demolition workers. The most observed weight category was 0 kg≤load<5 kg. Low back had the highest prevalence of MSDs symptoms (91.1%) and hip had the lowest prevalence of symptoms (6.7%). 

 PATH is applicable to building demolition process. Ergonomic intervention is necessary in high prevalence body regions such as lower back and wrist to decrease the symptoms. With respect to the results of PATH method, ergonomic interventions for trunk and leg(s) are necessary in all tasks, but only task #3 is in the priority of arm(s) intervention.

The aim of this study was to evaluate the performance of photoionization detector (PID) system as a substitution for gas chromatography in the measurement of a 3 xylene isomer mixtures as a representative of the volatile organic compounds in photocatalytic studies.

This study has been carried out by using test setup for generating known concentrations from equal ratio of 3 xylene isomers. The concentration values to be evaluated were classified into 4 concentration ranges from 0.1 of threshold limit values (TLV) to 2 of TLV to evaluate the PID system appliance compared with that in the reference method. The test was done 4 times for each evaluation concentration in 3 relative humidity levels (0%, 20%, and 80%).

The correlation between the PID results and the National Institue of Occupational Safety and Health (NIOSH) reference method results in an atmosphere with relative humidity of 0%, 20%, and 80% were good and, respectively, were 0.993, 0.992, and 0.991 and total correlation was 0.989. The paired t test indicates a significant difference between actual concentrations in reference method and the extracted concentration from PID.

Although the results presented by PID in the present study are different from those extracted from the reference method (from 10 to 260 ppm), the equipment response is linear. So, the results are acceptable in photocatalytic studies in case the contaminant concentration is measured by the same equipment either before or after the reactor for calculation of the removal efficiency. PID calibration with the test material(s) is recommended.

 The aim of this study was to study the sleep quality of truck and trailer drivers in Yazd and its relation with traffic accidents and associated expenses. 

 This cross-sectional descriptive study included nonrandom simple method including 200 truck and trailer drivers. A two-sectional questionnaire was used: the first section included the standard Pittsburgh sleep quality questionnaire, while the second section included demographic characteristics of the subjects. Data were analyzed using descriptive statistical method and T-test analysis through SPSS 17 software. 

 The mean daily sleep period of the subjects under study was 6.46 ± 1.8 h and the mean of sleep quality score was 7.22 ± 2.72 h. Of the total, 75.5% had a sleep quality score greater than 5 that depicts the low quality of sleep in them. 29.5% had suffered from accidents in the last decade and 28% of those were due to sleepiness. The distribution of the sleep quality score on basis of sleep duration and falling sleep time was meaningful. The distribution of history of cigarettes smoking, narcotics abuse, and use of sedatives on basis of sleep quality score was also significant (P</em> < 0.05).

The results showed that 75.5% of the truck and trailer drivers had sleep quality disorders and accidents resulting in injuries. Sleep quality in drivers who had precedence of accidents was lower than the drivers without any accidents so sleepiness can be one of the main causes of accidents among the professional drivers in Iran.

 This study aims to simulate dissolved oxygen of Zayandehrood river from regulating dam to Polle-Kalleh bridge using MIKE11 software that is a hydrodynamics and water quality model. 

 During 5 months the samples were taken from four hydrometric stations and water quality parameters such as dissolved oxygen, pH, BOD (1 day, 3 days, 5 days, and 7 days), NH 4</sub> , NO 3</sub> -</sup> phosphate (PO4 3-</sup> ), and temperature were measured. Morphological and hydrological data were provided and introduced into the model. The model was calibrated and its accuracy was investigated. 

 The results indicated that concentration of PO4 3-</sup> , BOD5</sub> , COD, NH 4</sub> , and NO3 -</sup> exceeded surface water standards from regulating dam to Pole-Kalleh bridge. The results of the prediction for the next 25 years indicated that due to growth of population and industries along the river, concentration of some pollutants will be increased. 

 The results indicated that although the current DO level is suitable for aquatic environment, this is not adequate for fish reproduction and migration. Prediction of the river water quality parameters for the future conditions showed that discharge of urban and rural wastewater to river should be avoided. In situations where release of effluent into the river is inevitable, nitrification process should be added to wastewater treatment processes.

 In this study the concentration of SO 2</sub> in Khark Island was evaluated via passive sampling. 

 The climate of the region and SO 2</sub> level were investigated during one year. For SO 2</sub> sampling, sulphatation pages was used and SO 2</sub> was determined by PbO 2</sub> method monthly. The climate data was obtained from Khark airport meteorology station. 

 For SO 2</sub> sampling, the sulphatation pages were installed at six locations in the region for a month. The results indicate the level of this gas is more than air standard. So that, SO 2</sub> concentration in residential Khark area was more than 8.5 ΅g/cm 2</sup> day. 

 High gas concentrations and climate conditions can cause accelerated corrosion of facilities and can have adverse effects on human and natural resources of the island.

 The aims of this study were to determine the efficiency of Kermanshah wastewater treatment plant (conventional activated sludge) and Gilan-e-Gharb wastewater treatment plant (stabilization ponds) in removal of organic matters (BOD 5</sub> and COD), suspended solids, total coliform, protozoan cyst, and parasitic eggs in order to reuse their effluent for agriculture. 

 In this study, the samples were taken every five days from both inlet and outlet of wastewater treatment plants (WWTPs) for five months. Identification and counting of the protozoa cysts and parasitic eggs was carried out using McMaster slide according to Bailenger method. Other parameters were determined according to standard methods. Appropriate statistical techniques (T-test, Kolmogorov Smirnov test, and Mann-Whitney U test, Using SPSS ver. 16) were applied to interpret data. 

 The efficiencies of Kermanshah wastewater treatment plant in removing BOD 5</sub> , COD, TSS, total coliform, parasitic eggs, and protozoan cyst were 82 ± 4%, 83 ± 2%, 78 ± 5%, 66.2 ± 4.2%, 97-99%, and 99-100%, respectively. The respective efficiencies for Gilan-e-Gharb stabilization ponds were determined as % 84 ± 3, %82 ± 8, %84 ± 5.3, %75 ± 6, %100, and %100. 

 According to the results, the removal efficiencies of all parameters except COD in stabilization ponds are higher than those in the activated sludge. Effluent quality in both plants met agricultural effluent reuse standards in view of all studied parameters except total coliform.

 The purpose of this study was to survey the antibiotics effects of oxytetracycline, tylosin, and amoxicillin on anerobic wastewater treatment process. 

 To evaluate the inhibitory antibiotics amoxicillin, tetracycline, and tylosin on biomass activity, specific methanogenic activity (SMA) using anerobic biomass batch; into 120 ml vials: 30 ml biomass and 70 ml substrate including volatile fatty acids, mainly acetic acid and various concentrations of antibiotics were added. Methane gas production replacement through solution of KOH (2 N) as an absorber of CO 2</sub> and bromine thymol blue as indicator was measured. Each batch was tested for 10 days. 

 Based on the findings, inhibitory concentration of oxytetracycline, amoxicillin, and tylosin were 8000, 9000, and 9000 mg/L, respectively. 

 This study showed that with increasing concentrations of antibiotics, the produced biogas volume from biomass per unit weight is decreased. COD removal was 42-82 % due to long retention time and adsorption to flocks.

 This study deals with molecular identification, susceptibility, and metal biosorption of a Geobacillus genospecies isolated from Deeymand hot spring at the south east region of Kerman, Iran. 

 Two samples were collected from water and sediment of the hot spring. Genomic DNA was extracted by sucrose lysis technique and polymerase chain reaction (PCR) was performed using the universal primers corresponding to Escherichia coli 16S rRNA gene. Both strands of the PCR product were sequenced by dideoxy chain termination method. The susceptibility of the isolate to Cu 2+</sup> and Ni 2+</sup> was determined by broth dilution method. Biosorption of dried biomass for the metal solutions was measured at different time intervals (5-300 min). Effect of temperature on biosorption of Cu 2+</sup> and Ni 2+</sup> was also determined. 

 Temperature of hot spring was 73°C and pH was 8. As result of sequencing of 16S rRNA gene, it was found that the organism had 99.8% similarity with member of genus Geobacillus. Phylogenetic tree and neighbor-joining phylogeny revealed that the isolate had 99.22% sequence similarity with Geobacillus uzenensis and 99.15% with Geobacillus jurassicus. The isolate exhibited minimum inhibitory concentration (MIC) of 4 mM to Cu 2+</sup> and 5 mM to Ni 2+</sup> . Minimum biosorption of Ni 2+</sup> occurred at 5 min (0.07%/0.1 g biomass) and maximum biosorption occurred at 120 min (29.6%/0.1 g biomass), while minimum biosorption of Cu 2+</sup> ion occurred within 5 min (16.6%/0.1 g biomass) and maximum occurred at 210 min (77.8%/0.1 g biomass) (P < 0.05). Biosorption of Ni 2+</sup> was the highest at 27°C (89.8%) and Cu 2+</sup> biosorption occurred at 65°C (77.8%). Geobacillus genospecies IRKM1 did not carry any plasmid. 

 The above results showed that the isolate was a member of Geobacillus spp. and the thermophilic bacteria was moderately resistant to Cu and Ni metals even though there was not any previous contamination of that biological niche. The organism exhibited highest biosorption of Cu 2+</sup> at 65°C and Ni 2+</sup> at 27°C. No plasmid was detected in the Geobacillus isolate.