Understanding the aging process of aerosol particles is important for assessing their chemical reactivity, cloud condensation nuclei activity, radiative properties and health impacts. In this study we investigate the aging of black carbon containing particles in an idealized urban plume using a new approach, the particleresolved aerosol model PartMC-MOSAIC. We present a method to estimate aging...

The desert of Sahara is one of the major sources of mineral dust on Earth, producing around 2×10 8 tons/yr. Under certain weather conditions, dust particles from Saharan desert get transported over the Mediterranean Sea and most of Europe. The limiting values set by the directive EC/30/1999 of European Union can easily be exceeded by 5 the transport of desert dust particles in all south Europea...

We used flow-switching type differential mobility particle sizer in a diameter range of 6–1000 nm and vehicle counting detectors with a time resolution of 10 min for 15 days in July 2010 in the Castle District Tunnel, Budapest. The total particle number concentrations varied from 5.1 ¥ 103 to 465 ¥ 103 cm–3 with a median of 143 ¥ 103 cm–3. The median was greater by a factor of 12 than that for ...

Soot particles produced by incomplete combustion processes are one of the major components of urban air pollution. Chemistry at their surfaces lead to the heterogeneous conversion of several key trace gases; for example NO(2) interacts with soot and is converted into HONO, which rapidly photodissociates to form OH in the troposphere. In the dark, soot surfaces are rapidly deactivated under atmo...

The international airport of Heathrow is a major source of nitrogen oxides, but its contribution to the levels of sub-micrometre particles is unknown and is the objective of this study. Two sampling campaigns were carried out during warm and cold seasons at a site close to the airfield (1.2 km). Size spectra were largely dominated by ultrafine particles: nucleation particles (< 30 nm) were foun...

OBJECTIVES We investigated the particle mass size distribution and chemical properties of air pollution particulate matter (PM) in the urban area and its capacity to induce cytotoxicity in human bronchial epithelial (BEAS-2B) cells. METHODS To characterize the mass size distributions and chemical concentrations associated with urban PM, PM samples were collected by a 10-stage Micro-Orifice Un...

The chemical nature of a large mass fraction of ambient organic aerosol particles is not known. High molecular weight compounds (often named humic-like substances) have recently been detected by several authors and these compounds seem to account for a significant fraction of the total organic aerosol mass. Due to the unknown chemical structure of these compounds quantification as well as a det...

air pollution in industrial and urban areas is one of the most important problems of environment which endangers humans' health; an example of these pollutants is the suspended particles in the air that with the increase of 10 in the air, the rate of mortality increases by 1 to 3 precent. this study was done during three seasons by determining ten sampling stations in each season and according ...

We studied acute responses of rat lungs to inhalation of urban particulate matter and ozone. Exposure to particles (40 mg/m3 for 4 hours; mass median aerodynamic diameter, 4 to 5 microm; Ottawa urban dust, EHC-93), followed by 20 hours in clean air, did not result in acute lung injury. Nevertheless, inhalation of particles resulted in decreased production of nitric oxide (nitrite) and elevated ...

BACKGROUND AND OBJECTIVES Because pulmonary circulation is the primary vascular target of inhaled particulate matter (PM), and nitric oxide is a major vasculoprotective agent, in this study we investigated the effect of various particles on the NO-cyclic guanosine monophosphate (cGMP) pathway in pulmonary arteries. METHODS We used intrapulmonary arteries and/or endothelial cells, either expos...