This study aimed to investigate young adults’ intention regarding water conservation in Iran. To achieve this goal, we applied a modified theory of planned behavior, with moral norm and self-identity being two additional determinants of intention and behavior. A face-to-face survey (N = 428) was undertaken in two universities, in south-western Iran. The reliability and validity of the instruments were examined and approved. Data were analyzed using structural equation modeling. The key findings were that self-identity, moral norm, attitude, and perceived behavioral control were all significant in determining intention, while subjective norm was not a significant predictor of intention. The findings of this study provided preliminary support for the theory of planned behavior and an extended model being used as an effective framework for examining water conservation among Iranian citizens. In addition, we found that self-identity and moral norm can capture a significant proportion of the variation in intention regarding water conservation.

Motor vehicle traffic is the main emission source of benzene. We undertook this study in order to compare benzene exposure and urinary levels of trans,trans-muconic acid (t,t-MA) in taxi drivers and petrol station workers. Air benzene levels were analyzed with gas chromatography using a Flame Ionization Detector. t,t-MA was extracted from urine and analyzed using high performance liquid chromatography. Significant differences in levels of urinary t,t-MA were found in drivers and petrol station workers when compared to a control group (p<0.05). Correlation coefficients between benzene in air and t,t-MA for petrol station workers and drivers were 0.65 and 0.30, respectively. The concentration of benzene in the breathing zone of petrol station workers was 2-3 times higher than drivers, and also 3 times greater than a threshold level (0.5 ppm) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH). The lowest benzene concentration at which urinary t,t-MA increased to a measurable level was approximately 0.17 ppm. In conclusion our results suggested that high benzene levels are emitted in petrol stations in west Iran. t,t-MA analysis was able to separate those exposed from the non-exposed benzene group when benzene in the breathing zone of subjects was greater than 0.17 ppm.

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The authors studied respiratory symptoms and lung function among welders at welding workshops, and among nonwelders, in Hamadan, Iran. They used a questionnaire to record demographic data, smoking habits, and respiratory symptoms. The authors measured pulmonary functions with subjects standing upright. They collected metal fume samples from the respiratory zone of workers and analyzed the samples by atomic absorption spectroscopy. The concentrations of iron and manganese were higher than threshold limit values. The prevalence of asthma and clinical symptoms was higher in welders than nonwelders. Also, bronchitis was more common among welders (17.45%) than among nonwelders (2.56%). The average respiratory function values of welders were lower than those of nonwelders, with a significant difference between the means (p < 0.001 for all terms). The results of this study also strongly suggest a synergistic relationship between the effects of smoking and welding exposure.

a b s t r a c tSince most industrial wastewaters contain phenol compounds, achieving eco-friendly and economic processes for filtration of such wastewaters is one of the concerns of environmental researchers. Thus, present study aims to determine the efficiency of bio-filter and activated sludge (BF/AS) combined process in phenol removal from aqueous solution. In this experimental study, BF/AS reactor in a pilot scale with continuous flow and useful volume of 24 L, made of Plexiglas was utilized. Effect of dissolved oxygen concentration, hydraulic residence time, mixed liquor suspended solids (MLSS) and glucose concentration on phenol removing efficiency were evaluated. In order to determine the phenol removal model and optimum removal conditions using central composite design in response surface methodology environment, the reactor was studied in separate runs according to software design. Accuracy of results was evaluated in MLSS concentrations of 2,250 mg/L, glucose of 250 mg/L and dissolved oxygen of 3 mg/L and quadratic model (R 2 = 0.99) well fitted to the results. With regard to high yield of BF/AS biological system in decreasing phenol content from wastewater, the system under study could be used widely in refining the toxic wastewaters of industries given the appropriate operation conditions.

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Removal of toluene using cobalt oxide supported on sepiolite catalysts was investigated. Deposition precipitation method was used to prepare the catalysts. The catalysts were characterized using X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, thermogravimetric analysis (TGA) and Brunauer-Emmet-Teller methods. The results of catalytic testing showed that 20% cobalt oxide/sepiolite (Co20/Sep) had higher catalytic activity for degradation of toluene. A temperature of 400 °C was found to be the optimum calcination temperature for Co20/Sep, since it achieved 90% toluene conversion at about 300 °C. The results showed that the selectivity of the catalysts towards CO 2 was complete and no byproducts were detected. Stability tests also indicated that Co20/Sep remains stable at 320 °C with complete conversion of toluene after 24 h. In conclusion, the results of this study confirmed sepiolitesupported cobalt oxide catalyst as an efficient catalyst for degradation of toluene.