background: the main objective of this study was to determine the respiratory health symptoms and lung function among roadside hawkers in serdang, malaysia and its association with traffic-related exposures. methods: this cross-sectional comparative study was conducted among 60 roadside hawkers while 60 restaurant workers were included as the comparative group in 2015. a questionnaire was used ...

The hypothesis of hormesis - that substances that harm health at high exposures can reduce risks below background at low exposures, e.g., if they activate defenses without overwhelming them - becomes important for practical policy making if it holds for regulated substances. Recently, the U.S. EPA concluded that reductions in ambient concentrations of fine particulate matter (PM2.5) in air caus...

Particulate matter is defined as a mixture of airborne solid particles and liquid droplets that can be inhaled and may cause serious health problems. Such elements are currently measured utilizing air quality monitoring devices that provide information on PM 10 and PM 2.5 levels giving information on pollution levels. However, many difficulties are encountered in the determination of nanosized ...

Most parts of the urban areas are faced with the problem of floating fine particulate matter. Therefore, it is crucial to estimate the amounts of fine particulate matter concentrations through the urban atmosphere. In this research, an artificial neural network technique was utilized to model the PM2.5 dispersion in Tehran City. Factors which are influencing the predicted value consi...

background: the aim of study was to measure particle matter concentration (pm 1, pm 2.5 and pm 10 ) during normal, semi-dust and dust-event days. the impacts of some meteorological factors on particle matter concentrations were also investigated. methods: samples were collected by grimm aerosol technik (gmbh model 1/108 germany) from november 2011 to may 2012. temperature, humidity, wind speed ...

24-hour samples of pm1 (submicron particles, aerodynamic diameters ≤1 μm) and pm2.5(fine particles, aerodynamic diameters ≤ 2.5 μm) were collected at a quasi-rural area in racibórz (1 january-30 june 2011). the samples were analysed for carbon (organic and elemental), water-soluble ions (na+,nh4 +, k+, mg2+, ca2+, cl-, no3 -, so4 2-) and concentrations of 21 elements with a carbon analyser (sun...

in the industrial area of elefsis, greece, aerosol samples from the atmosphere were collected using a stacked filter unit sampler, which separates the airborne particulate matter into coarse (pm2.5-10) and fine (pm2.5) size fractions. the samples collected during the period january 2005 to march 2006, were analyzed by anodic stripping voltammetry (asv) and inductively coupled plasma atomic emis...

The USEPA has proposed to regulate PM(coarse) (particulate matter 2.5 to 10 microm in diameter). Exceedance of the proposed National Ambient Air Quality Standard (NAAQS) for PM(coarse) is expected within the Columbia Plateau of the Pacific Northwest United States based on the high frequency of dust storms and the large contribution of crustal material to fugitive dust in the region. The objecti...

OBJECTIVE To measure levels of fine particulate matter in the rear passenger area of cars where smoking does and does not take place during typical real-life car journeys. METHODS Fine particulate matter (PM(2.5)) was used as a marker of secondhand smoke and was measured and logged every minute of each car journey undertaken by smoking and non-smoking study participants. The monitoring instru...