Physical Activity- and Alcohol-dependent Association Between Air Pollution Exposure and Elevated Liver Enzyme Levels: An Elderly Panel Study / 예방의학회지

OBJECTIVES: The deleterious effects of air pollution on various health outcomes have been demonstrated. However, few studies have examined the effects of air pollution on liver enzyme levels. METHODS: Blood samples were drawn up to three times between 2008 and 2010 from 545 elderly individuals who regularly visited a community welfare center in Seoul, Korea. Data regarding ambient air pollutants (particulate matter < or =2.5 mum [PM2.5], nitrogen dioxide [NO2], ozone [O3], carbon monoxide, and sulfur dioxide) from monitoring stations were used to estimate air pollution exposure. The effects of the air pollutants on the concentrations of three liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma-glutamyltranspeptidase [gamma-GTP)]) were evaluated using generalized additive and linear mixed models. RESULTS: Interquartile range increases in the concentrations of the pollutants showed significant associations of PM2.5 with AST (3.0% increase, p=0.0052), ALT (3.2% increase, p=0.0313), and gamma-GTP (5.0% increase, p=0.0051) levels; NO2 with AST (3.5% increase, p=0.0060) and ALT (3.8% increase, p=0.0179) levels; and O3 with gamma-GTP (5.3% increase, p=0.0324) levels. Significant modification of these effects by exercise and alcohol consumption was found (p for interaction <0.05). The effects of air pollutants were greater in non-exercisers and heavy drinkers. CONCLUSIONS: Short-term exposure to air pollutants such as PM2.5, NO2, and O3 is associated with increased liver enzyme levels in the elderly. These adverse effects can be reduced by exercising regularly and abstinence from alcohol.

Enhancement of 4-nitrophenol ozonation in water by nano ZnO catalyst

The removal of 4-nitrophenol [4NP] from aqueous solution by ozone combined with nano-ZnO was investigated in a laboratory-scale reactor in which pH of solution, ZnO dosage and initial 4-nitrophenol concentration were considered as variables. The degradation of 4-nitrophenol was determined using UV-Vis and HPLC methods. Interestingly, the degradation of 4-nitrophenol was high under acidic condition where the degradation was about 93% at initial phenol solution pH=3. It was due to aggregation of nano-ZnO particles above pH=6.5. This result was different from the case of ozonation alone, in which higher pH had positive effect on the degradation of 4-nitrophenol due to the formation of hydroxyl radical. As expected, degradation efficiency increased by increasing the nano ZnO dosage and initial 4-nitrophenol concentration. It was found that the nanosized ZnO enhanced the degradation of ozone and the catalytic ozonation enhanced the degradation of 4-nitrophenol on the surface of the nanosized ZnO. In addition, the degree of degradation was also determined indirectly through Total Organic Carbon [TOC] of the samples. Carbon mineralization of 4-nitrophenol was obtained as 13.68% and 60.34% during ozonation and nano-ZnO catalytic ozonation, respectively, after 30 min reaction, proving that combined ozonator and nano-ZnO for reduction of TOC is more efficient. Also a high degree of nitrogen mineralization during catalytic ozonation was achieved at pH= 3 [7.61mg/L]

Ozonation of exhausted dark shade reactive dye bath for reuse.

Exhausted reactive dye bath of dark shades were collected from cotton knit wear dyeing units in Tirupur. Ozonation was conducted in a column reactor system fed with ozone at the rate of 0.16 g/min to assess its efficiency in reducing the color, chemical oxygen demand and total organic carbon. The potential of the decolorized dye bath for its repeated reuse was also analyzed. The results from the reusability studies indicate that the dyeing quality was not affected by the reuse of decolorized dye bath for two successive cycles. Complete decolorization of the effluent was achieved in 60 minutes contact time at an ozone consumption of 183 mg/L for Red, 175 for Navy Blue and 192 for Green shades respectively. The corresponding COD removal was 60%, 54% and 63% for the three shades while TOC removal efficiency was 59%, 55% and 62% respectively. It is concluded that ozonation is efficient in decolorization of exhausted dye bath effluents containing conventional reactive dyes. However, the corresponding removal of COD from the textile effluent was not significant.

Using respirometer in biodegradation phenomenon of natural organic matters.

This study conducted in monitoring respirometer oxygen consumption of aerobic microorganism during biodegradation processes of ozonated organic matters, which can estimate both biodegraded efficiency and coefficient of natural organic matters (NOMs) in water source. It can be proposed that different ozone dosage might change biodegradation characteristics of organic matters. The result reveals that higher ozone dosage may cause higher biomass yield coefficient of microorganism, and cultured microorganism may easily utilize biodegradation organic matters (BOMs) produced by ozonation, finally increasing overall removal efficiency. Therefore, using respirometer to evaluate the production of BOMs by ozonation before the biological treatment is effective for controling ozone dosage and enhancement of NOMs removal by biological processes.

El ozono como molécula reactiva: concepto actual / The ozone by reactive molecule: actual concept

Los radicales libres son especies químicas de gran reactividad. El ozono se caracteriza por ser un contaminante del aire, que está presente sobre todo en las grandes ciudades, a pesar de que no es propiamente un radical libre, es promotor de varios de ellos, por ejemplo, los radicales hidroxilo y peróxido. Los radicales libres también se generan como parte del metabolismo celular y son controlados por mecanismos de carácter endógeno, principalmente de tipo enzimático, resaltan por su importancia, las enzimas superóxido dismutasa, catalasa y glutatión peroxidasa. Diversos reportes señalan la participación del ozono en la producción de alteraciones en funciones neurológicas, conductuales, endocrinas y genéticas entre otras. Por otra parte, bajo condiciones controladas, el ozono ha sido utilizado con fines terapéuticos en el tratamiento de enfermedades virales. De manera que el ozono, puede verse como benéfico o dañino, dependiendo de su concentración y de la capacidad del metabolismo celular del organismo, para regular la producción de radicales libres, hasta culminar con la oxidación de moléculas orgánicas y producir CO2 y H2O.

Efectos del ozono sobre el sistema respiratorio / Effects of tropospheric ozone on respiratory system

El ozono (O3) es el principal componente de los contaminantes fotoquímicos del aire y se forma cuando los óxidos de nitrógeno naturales o antropogénicos reaccionan con los compuestos orgánicos volátiles en presencia de la radiación solar ultravioleta. Típicamente el nivel troposférico del O3 urbano es un problema desde el final de la primavera hasta comienzos del otoño. Se piensa que los efectos del O3 derivan principalmente de la formación de radicales libres. La exposición aguda a ozono en seres humanos causa dolor retroesternal en inspiración profunda, tos irritativa, disminución de CVF y VEF1 e inflamación de las vías aéreas asociada a hiperreactividad bronquial. La exposición prolongada produce bronquiolitis respiratoria crónica que puede derivar en una remodelación de la estructura pulmonar. En niños observados en un período de 3 años, el O3 se asoció con una disminución del crecimiento de CVF, VEF1 y FEM50. La susceptibilidad al O3 varía según la población expuesta, siendo especialmente sensibles los niños y las personas con enfermedades respiratorias preexistentes