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Exposure to high concentrations of ambient particulate matters (PMs) has a strong potential to cause adverse respiratory outcomes. Recent PMs increase due to the drying of Urmia Lake remains a major health challenge in the west of Iran. This study was conducted to assess the correlation of the exposure to PM10 and PM2.5 on respiratory hospitalization in Urmia, Iran. Daily hospital admissions and air pollutants data were collected during the study period. Conditional logistic regression models were used to estimate the risks of hospitalization in exposure to PMs. There was a significant adverse effect between PM10 and asthma hospitalization based on the adjusted and unadjusted models. In the adjusted model, an interquartile range (IQR) increment of PM10 and PM2.5 increased the risk of admissions for asthma by [1.124 (1.062-1.191)] and [1.117 (1.055-1.184)], respectively. The estimated odds ratio for females was 1.5 times higher than males. A comparison of the associated risks of PM2.5 indicates a significant increase in the group aged 18-60 and >60 years. Not including asthma, a significant correlation was found between all causes of hospitalization and exposure to PM2.5 during cold seasons. Taken together, the results provide important insights into that exposure to ambient PMs were associated with an increased risk of respiratory hospitalization. A case-crossover design was used to evaluate the correlation of PMs and hospital admissions. Conditional logistic regression models were used to estimate the risks. The estimated odds ratio for females was 1.5 times higher than males. A significant correlation was found between hospitalization and PM2.5 exposure during cold seasons. Group aged 18–60 years and >60 years were faced at more risks in exposure to PM2.5. [ABSTRACT FROM AUTHOR]

Background and purpose: Ammonia in form of ammonium ions pollutes the acceptor water through industrial, domestic and agricultural wastewater. Ammonium ions are toxic and could decrease the dissolved oxygen in water and endanger the aquatic life. One of the conventional methods for removing ammonia from water and wastewater is exchanging the ions using zeolites. The aim of this study was to assess the efficacy of zeolite Clinoptilolite in removing ammonia from water, in both batch and continuous systems. Materials and methods: In this study batch experiments were exposed to different concentrations of natural Clinoptilolite (5, 10, and 50 g/l) with aqueous solution containing ammonium ions (1, 5and, 10 mg/l) in different exposure times (10 to 240 minutes). The continuous experiments were also conducted at ammonium concentrations of 5 and10 mg/l. Results: The maximum ammonium absorption occurred at pH=7 and in 60 minutes exposure time. Increase in initial concentration of ammonium increased the sorption capacity. Also, sorption capacity decreased when the absorbent material increased. Considering higher correlation coefficient (R2) the isotherm obtained in this study matches the Freundlich isotherm model. The results of column tests showed longer time to reach the breakpoint when initial concentration of ammonium decreased. Breakpoints for ammonium concentrations of 5 and 10 mg/l were 6.45 and 6.32 mg/g, respectively. Conclusion: This study proved that ion exchange using zeolite Clinoptilolite is a low cost method that could result in complete removal of ammonium from water. [ABSTRACT FROM AUTHOR]