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Fine particulate matter (PM) is associated with an increased risk of respiratory and cardiovascular diseases. Fine PM absorbs water molecules at high relative humidity, and then their size grows. Such hygroscopic growth causes a large error when monitoring PM concentrations. To lower the relative humidity, monitors use an indirect heating device, which is large and consumes large amounts of power. The problem with conventional particle separators is that their efficiency depends on temperature and humidity, and their traditional structure, which lets air flow downward. As such, this paper addresses these problems and presents a PM monitor with a new type of dryer that is free from these problems. The proposed monitor requires less energy and has an efficient dehumidifier and a new structure in which air flows upward. The presented experiments were conducted to compare the proposed device with a reference monitor managed by a governmental institute, and to evaluate the effect of the dehumidifier, the relative precision of the proposed devices, and the correlation with the reference monitor. The experimental results showed that the proposed monitor satisfies the U.S. EPA indicators for class III monitors.

Particulate matter (PM) air pollution has become a serious environmental problem in Nanjing and poses great health risks to local residents. In this study, characteristics of particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5) over Nanjing were analyzed using hourly and daily averaged PM2.5 concentrations and meteorological parameters collected from nine national monitoring sites during the period of March 2014 to February 2017. Then, the integrated exposure-response (IER) model was applied to assess premature mortality, years of life lost (YLL) attributable to PM2.5, and mortality benefits due to PM2.5 reductions. The concentrations of PM2.5 varied among hours, seasons and years, which can be explained by differences in emission sources, secondary formations and meteorological conditions. The decreased ratio of PM2.5 to CO suggested that secondary contributions decreased while the relative contributions of vehicle exhaust increased from increased CO data. According to the values of attributable fractions (AF), stroke was the major cause of death, followed by ischemic heart disease (IHD), lung cancer (LC) and chronic obstructive pulmonary disease (COPD). The estimated total deaths in Nanjing due to PM2.5 were 12,055 and 10,771, leading to 98,802 and 87,647 years of life lost in 2014 and 2015, respectively. The elderly and males had higher health risks than youngsters and females. When the PM2.5 concentrations meet the World Health Organization (WHO) Air Quality Guidelines (AQG) of 10 μg/m3, 84% of the premature deaths would be avoided, indicating that the Nanjing government needs to adopt more stringent measure to reduce PM pollution and enhance the health benefits.

The impact of ship emissions on air pollution in harbours is probably one of the lesser-understood aspects of anthropogenic pollution. Vessels are often powered by relatively old engines and at the
same time quality of fuels is often questionable. These factors have potential to significant increase air pollution in busy harbours. It is well know that V/Ni ratio higher than 2.5 are good indicators of
heavy oil combustion from the ship engines. To evaluate this contribution to the air pollution in the harbour of Rijeka we measured concentrations of V and Ni in fine aerosols (PM2.5).
Over the 300 fine aerosol samples were collected during the three years period (February 2012 – June 2015) and analyzed by two analytical techniques; X-ray Fluorescence and Laser Integrated Plate
Method at the Laboratory for Elemental-Micro Analysis (Department of Physics University of Rijeka). Concentrations of 18 elements (Si to Pb) were obtained as well as the black carbon (BC) component. The results were statistically evaluated by means of the positive matrix factorization. In nearly 15% of samples, concentration ratio (V/Ni) was found to be around 3 indicating that during those days the source that we named "ship emission" was present in fine aerosol pollution with major components such as S, BC and traces K, V, Fe, Cl, Br, Pb and Ni. This anthropogenic source represented approximately 10% from the total fine aerosol mass.