# Examining the Amount of Particulate Matter (PM) Emissions in Urban Areas
## 1 Introduction  
The results of recent studies have found that air quality in cities has deteriorated due to the increasing concentration of human activities that produce polluting emissions [1]. The main cause of current air pollution is mainly emissions from household heating and emissions from transport. Studies [2; 3] have shown that solid particles and nitrogen oxides contribute to excessive pollution. Their increased concentration is particularly observable in metropolitan areas with an extreme number of cars. Residents in such conditions have difficulty breathing. In such environmental conditions, pollutants begin to accumulate, especially particulate matter PM\({}_{10}\) and PM\({}_{2.5}\)[4]. These are very small particles that are hardly visible to the naked eye. Particulate matter from city roads contain toxic metals and act as carriers of pollutants released into the air as well as carcinogens, which pose a potential risk to human health [5; 6]. The resuspension of PM and road wear particles accumulated on the surface, in addition to fine and coarse space particles that are mostly produced by tire and brakewear, are the main contributors to non-exhaust emissions [7; 8]. Particulate matter (PM) air pollution is largely the result of burning fossil fuels. The AQLI (Air Quality Life Index) study shows that the life expectancy of all women, men, and children worldwide who live in areas with a PM concentration higher than what was considered safe by the World Health Organization (WHO) [9] could be reduced by almost 2.2 years. Poor air quality shortens human lives around the world and has a negative effect worse than cigarettes, therefore, there is no greater risk to human life at present [10]. When investigating the concentration of particulate matter, size is important. A study by [PERSON] et al. points to the formation and impact of particles smaller than 1 \(\upmu\)m in metropolitan areas [11]. The smaller the fine dust particles, the more insidious their inhalation is for our organisms. Much also depends on their chemical composition. PM is composed of liquid and particulate matter, that can remain suspended in the air for long periods of time. Particles that are larger than PM\({}_{10}\) are already filtered out in the nasal cavity and do not pose a considerable risk to human health. However, smaller particles (PM\({}_{2,5}\)) penetrate the larynx and lower respiratory tract, subsequently settling in the bronchi. Because of their small sizes, PM\({}_{2.5}\) particles can remain in the air for days after being emitted or formed in the atmosphere and can be transported long distances from their source [12; 13; 14]. According to the World Health Organization, PM was responsible for 3 million premature deaths worldwide in 2016 [15]. Decreasing PM\({}_{2.5}\) levels by 10 \(\upmu\)g/m\({}^{3}\) could increase life expectancy by 0.61 years [16]. Moreover, the results of several studies have shown a significant positive association between the quantities of PM\({}_{2.5}\) in road dust and the frequency of hospitalization due to cardiovascular and respiratory complications [17; 18]. Young children, the elderly, and people suffering from allergies or asthma are sensitive to air pollution. The biggest air quality problem in Slovakia is air pollution comprising dust particles (PM\({}_{10}\)); furthermore, PM also causes the greatest damage to human health in Europe [19; 20; 21]. Air pollution is hard to escape, no matter where one is. Particulate matter in general can come from very diverse sources both natural and anthropogenic. The natural sources include processes that normally occur in nature (forest fires, erosion processes, etc.). Anthropogenic sources include emissions from combustion processes household heating, transport, electricity production, heating plants, waste incinerators, and various other production processes. To a lesser extent, increased dustiness is also contributed by dust from the road residues from the wear of brakes and tires, winter litter, and road pollution.