Tab. I.5 Brief characteristics, overview of major emission sources and major effects of ambient air pollutants

Pollutant and its sources
Health effects
 
Environmental effects
Suspended particles
Primary particles are emitted directly as liquid or solid particles. Secondary particles are formed in the atmosphere during physical or chemical processes from their gaseous precursors SO2, NOx, VOC and NH3 (Pöschl 2011; EEA 2013a). The largest anthropogenic sources in the CR: residential combustion, road transport, farm-level agricultural operations and transport of agricultural products and public electricity and heat production
 
The effect depends on the size, shape and composition of the particles. The short-term increase of daily PM10 concentrations contributes to the growth of total morbidity and mortality, caused mainly by cardiovascular diseases, to the growth of the number of persons hospitalized due to respiratory tract diseases, increase of infant mortality, increase of cough occurrence and breathing problems, mainly in asthmatics (SZÚ 2013).The long-term increased concentrations can result in reduced pulmonary function, increased morbidity due to respiratory tract diseases and increased incidence of chronic bronchitis symptoms and decreased lifespan, especially due to increased mortality in the elderly and sick due to cardiovascular diseases and probably also lung cancer (SZÚ 2013). The particles affect both animals and humans; they affect plant growth and ecosystem processes; they may damage and soil the buildings and cause impaired visibility (EEA 2013a).
Benzo[a]pyrene
Benzo[a]pyrene, occurring in the atmosphere primarily bound to the particles, is a suitable marker of ambient air pollution caused by PAH. The reason is its stability and relatively constant contribution to carcinogenic activity of the mixture of PAH bound to the particles (EC 2001a).The major sources of
benzo[a]pyrene in the CR: residential combustion, road transport and stationary combustion in manufacturing industries and construction (iron and steel)
 
PAH are dangerous mainly due to carcinogenic effects and the threat to the healthy development of foetus (EEA 2013c). Prenatal exposure to PAH is related with markedly lower birth weight (Choi et al. 2006) and probably also with negative impact on cognitive development of young children (Edwards et al. 2010).Benzo[a]pyrene is classified as proven human carcinogen (IARC 2014). Besides, it can cause irritation of the eyes, nose, throat and bronchi (EEA 2013c). PAH can bioaccumulate and enter the food chain (DOE 2012, EEA 2013a).
Nitrogen oxides
The term “nitrogen oxides” (NOx) refers to nitric oxide (NO) and nitrogen dioxide (NO2). More than 90 % of anthropogenic emissions of NOx are represented by NO emissions. The major anthropogenic sources of NOx in the CR: road transport, off-road vehicles and other machinery in agriculture and fishery and forestry, public electricity and heat production, stationary combustion in manufacturing industries and construction (chemicals and others).
 
As concerns the impact on human health, the most significant form is NO2 (WHO 2000). NO2 can affect mainly the respiratory tract. Short-term exposure to NO2 can cause adverse effects on human health, such as changes of pulmonary function in susceptible groups of population. Long-term exposure may increase susceptibility to respiratory infections (EEA 2013a). It is difficult to separate NO2 effects from the effects of other simultaneously acting substances, mainly suspended particles (SZÚ 2013). NOx contribute to acidification and eutrophication of soil and water. High NOx concentrations can lead to damage to plants. NOx act as precursors of ground-level ozone and particles (EEA 2013a, DOE 2012).
Ground-level ozone
Ozone (O3) is a secondary pollutant without its own emission source; it is formed as a part of photochemical smog. It is formed under the influence of solar radiation during a series of reactions mainly between NOx, VOC and oxygen. (EEA 2013a). Ozone can be transported over long distances, accumulate and reach high concentrations far from its place of origin (DOE 2012).
 
The short-term studies show that O3 concentrations may have adverse effects on pulmonary function leading to lung inflammation and respiratory problems (EEA 2013a). Those suffering from asthma and chronic disease of respiratory tract or cardiovascular disease are the most sensitive group (SZÚ year unknown).Longer stay in the area with increased concentrations may lead to sore eyes, nose, throat and headache (SZÚ year unknown; EEA 2013c). Damages vegetation, impairing plant growth and decreasing crop yields; can damage forest ecosystems and reduce biodiversity (EEA 2013a).
Benzene
Benzene is present in the atmosphere mainly due to anthropogenic activities. The largest source of benzene emissions is represented by incomplete combustionof fuels used by vehicles. Other sources are domestic heating, oil refining, and the handling, distribution and storage of petrol (EEA 2013a).
 
Benzene ranks among human carcinogens (IARC 2014). At high concentrations it can have hematotoxic, genotoxic and immunotoxic effects (SZÚ 2012). Bioaccumulation; it can damage leaves of agricultural crops and cause death in plants (EEA 2013a).
Lead
Most lead contained in the atmosphere is released from anthropogenic emission sources. The main sources in the CR: iron and steel production, stationary combustion in manufacturing industries and construction (iron and steel and other), public electricity and heat production, residential combustion and road transport (passenger cars).
 
Long-term exposure results in harmful impacts on biosynthesis of haem, on nervous system and blood pressure in humans. The exposure to lead brings the risk for the developing foetus; it may negatively influence brain development and, consequently, the mental development, (Černá 2011; EEA 2013a). As concerns its carcinogenic effects lead is classified within 2B group – possibly carcinogenic to humans (IARC 2014). Lead can accumulate in the bodies of organisms (bioaccumulation) such as fish and it can enter the food chain (DOE 2012, EEA)
Cadmium
Cadmium is bound mainly to the particles with aerodynamic diameter up to 2.5 μm (EC 2001b). The main sources in the CR: public electricity and heat production, iron and steel production, stationary combustion in manufacturing industries and construction (iron and steel, chemicals and other) residential combustion and road transport (passenger cars).
 
Long-term exposure to cadmium affects the function of kidneys. It can also have negative impacts on the respiratory tract; the effects of cadmium exposure include also lung cancer (WHO 2000). Bioaccumulation (EEA 2013a).
Arsenic
Arsenic occurs largely in particles with aerodynamic diameter up to 2.5 µm (EC 2001b). The main sources in the CR: public electricity and heat production, residential combustion, stationary combustion in manufacturing industries and construction (non-ferrous metals and other) and iron and steel production.
 
High concentrations affect the nervous system (SZÚ 2012). Lung cancer is considered to be the critical effect following the long-term inhalation (EC 2001b; WHO 2000). Bioaccumulation; it reduces plant growth and crop yields from soils containing arsenic (EEA 2013a).
Nickel
Nickel is found in particles in several chemical compounds with various levels of toxicity for human health and ecosystems. The main sources in the CR: public electricity and heat production, stationary combustion in manufacturing industries and construction (chemicals, iron and steel and other).
 
Nickel can affect the respiratory and immune systems in humans (WHO 2000, EEA 2013a). Nickel compounds are classified as proven human carcinogens, metallic nickel and its alloys are classified as possibly carcinogenic to humans (IARC 2014). Nickel may cause the pollution of soils and waters.
Sulphur dioxide
Sulphur dioxide (SO2) is emitted to the atmosphere during the combustion of sulphur-containing fuels. The most significant anthropogenic sources in the CR: public electricity and heat production, residential combustion, stationary combustion in manufacturing industries and construction (chemicals and iron and steel).
 
SO2 causes irritation of the eyes and respiratory tract. High SO2 concentrations can lead to respiratory problems. Inflammation of the respiratory tract causes coughing, mucus secretion, aggravation of asthma and chronic bronchitis, and makes people more prone to infections of the respiratory tract. Those suffering from asthma and chronic lung disease are the most sensitive towards SO2 exposure (EC 1997b; WHO 2014). SO2 contributes to acidification of the environment. SO2 contributes also to the formation of secondary suspended particles with the evidenced negative impact on human health (EEA 2013a).
Carbon monoxide
Carbon monoxide (CO) is a gas emitted due to incomplete combustion of fossil fuels. The largest source of CO emissions in the CR is road transport, although after the implementation of catalytic converters CO emissions caused by traffic decreased. Further major sources: stationary combustion in manufacturing industries and construction (chemicals and iron and steel), household heating and steel and iron production.
 
CO binds with haemoglobin more strongly than oxygen and thus reduces the oxygen-carrying capacity of the blood. Those suffering from cardiovascular disease are the most sensitive towards CO exposure (EEA 2013a). Toxic effects of CO become evident in organs and tissues with high oxygen consumption, such as the brain, the heart and skeletal muscles. It is dangerous also for the developing foetus (WHO 2000). CO can contribute to the formation of ground-level ozone (EEA 2013a, DOE 2012).