Human exposure to nitrogen dioxide (NO2), an air pollutant of increasing interest in biology, results in several toxic effects to human health and also to the air microbiota. The aim of this study was to investigate the bacterial response to gaseous NO2. Two Pseudomonas fluorescens strains, namely the airborne strain MFAF76a and the clinical strain MFN1032 were exposed to 0.1, 5, or 45 ppm conc...

BACKGROUND With growing urbanization, traffic has become one of the main sources of air pollution in Nepal. Understanding the impact of air pollution on health requires estimation of exposure. Land use regression (LUR) modeling is widely used to investigate intraurban variation in air pollution for Western cities, but LUR models are relatively scarce in developing countries. In this study, we d...

Antihypertensive Inorganic Nitrate and Nitrite: What Is the Underlying Mechanism? To the Editor: l-Arginine, organic nitrates such as nitroglycerin, inorganic nitrate (NO3 −), and inorganic nitrite (NO2 −) are precursors of nitric oxide (NO), a potent vasodilator and blood pressure–lowering molecule. How NO is released from nitroglycerin,1 NO3 −, and NO2 − is incompletely understood. Ghosh et a...

The effect of NO2 on secondary organic aerosol (SOA) formation from ozonolysis of α-pinene, β-pinene, 1-carene, and limonene was investigated using a dark flowthrough reaction chamber. SOA mass yields were calculated for each monoterpene from ozonolysis with varying NO2 concentrations. Kinetics modeling of the first-generation gasphase chemistry suggests that differences in observed aerosol yie...

The photochemistry of nitrate ions in bulk aqueous solution is well known, yet recent evidence suggests that the photolysis of nitrate may be more efficient at the air-water interface. Whether and how this surface enhancement is altered by the presence of different cations is not known. In the present studies, thin aqueous films of nitrate salts with different cations were deposited on the wall...

The exploration of spatial variation and predictors of the effects of nitrogen dioxide (NO2) on fatal health outcomes is still sparse. In a multilevel case-crossover study in Beijing, China, we used mixed Cox proportional hazard model to examine the citywide effects and conditional logistic regression to evaluate the district-specific effects of NO2 on cardiovascular mortality. District-specifi...

Synthesis of nitrite (NO2-) and nitrate (NO3-) was studied in the macrophage cell lines RAW 264.7, WEHI-3, PU5-1.8, J774A.1, and P388D1 and compared to the synthesis by thioglycolate-elicited peritoneal macrophages from C3H/He and C3H/HeJ mice. Treatment with Escherichia coli lipopolysaccharide (LPS) induced NO2-/NO3- synthesis by all the cell lines except P388D1, which remained unresponsive at...

The 204- and 229-nm excited UV resonance Raman spectra of wastewater solutions containing sodium nitrite and nitrate were measured in the concentration range 7 microM to 3.5 mM (0.1-50 ppm nitrogen). The other chemical species present in wastewater do not interfere with Raman measurements of NO2-/NO3- bands. We observe detection limits of < 14 microM (< 200 ppb) for both NO2- and NO3-. UV reson...

aims: tehran’s uncontrolled expansion, which promoted housing, public utilities, industries and increase of vehicles caused the problem of air pollution. necessary information about air quality in different places and different times is the first step of combating the air pollution. the purpose of this study was to investigate the annual, monthly and hourly average of 5 criteria air pollutants ...

The first quantitative characterization of the interaction of NO2(-) with the Cu-containing dissimilatory nitrite reductase (NiR) of Alcaligenes xylosoxidans using steady-state kinetics, equilibrium gel filtration and EPR spectroscopy is described. Each molecule of this protein consists of three equivalent subunits, each containing a type-1 Cu atom and also a type-2 Cu atom at each subunit inte...