At present, ambient air pollution is one of the most serious problems in the field of environmental protection. Polluted air has provable negative effects on human health. Pollutants can cause a wide range of health problems, from less severe conditions to serious diseases and even premature deaths. Pollutants also negatively affect vegetation. They can influence its growth and cause decreased yields of agricultural crops and forests. They also cause eutrophication and acidification of soil and water ecosystems1, followed by changes in species composition and the reduction of plant and animal species diversity. Many pollutants have the ability to accumulate in the environment, to negatively influence whole ecosystems and to enter the food chain. In addition, some of them directly or indirectly influence the climate system of the Earth. It is also necessary to mention the damages caused by ambient air pollutants to materials and buildings, often historical ones.
Measures implemented in recent decades mainly to control pollution from large sources have helped reduce emissions. In spite of that, a number of economic and social activities still produce amounts of pollution which in combination with meteorological and dispersion conditions result in exceedances of limit values for some pollutants. At present the most problematic among all monitored pollutants are suspended particles and polycyclic aromatic hydrocarbons bound to them. In summer periods, the limit values for ground-level ozone are also exceeded at many localities.
Local household heating using solid fuels is generally a significant source of suspended particles and polycyclic aromatic hydrocarbons (both in the Czech Republic and across EU countries). In areas burdened by traffic, increased concentrations of nitrogen dioxide may occur. Transport is another important source of suspended particles and polycyclic aromatic hydrocarbons. Public and industrial energetics, agriculture and solvent use in the case of non-methane volatile organic compounds (NMVOC) still remain significant sources of pollution. However, the particular contributions of individual sources to the overall air pollution levels vary in different areas, depending not only on the composition of sources in the given area, but also on the transfer of pollutants from other areas.
I.1 OBJECTIVES OF THE PUBLICATION
The yearbook ‘Air Pollution in the Czech Republic in 2014’, together with the electronically published annual Summary Tabular Survey, constitute a complete overview of data and information on ambient air quality in the territory of the Czech Republic in the respective year. The ambient air quality evaluation is based on measured data, collected by the Air Quality Information System (AQIS) of the Czech Hydrometeorological Institute (CHMI) using other data sources and mathematical tools. The Summary Tabular Survey presents measured and verified air pollution data and data on the chemical composition of atmospheric precipitation at individual localities. The yearbook presents commented comprehensive information in the form of maps, graphs and tables.
The introduction to this yearbook deals with the political and legislative framework of ambient air quality protection in the Czech Republic, the characterization of main air pollutants from the perspective of their possible impacts on human health and the environment, and phenomena which govern pollutant levels in the atmosphere (i.e. sources of pollution and meteorological and dispersion conditions in the given year). The main part of this yearbook is dedicated to ambient air quality and the occurrence of smog situations in the Czech Republic. Chapters dealing with the no less important topics of atmospheric deposition and emissions of greenhouse gases are found near the end of the publication. Information about the database used, the methodology and the mapping uncertainty is presented in the last two chapters.
Ambient air quality is evaluated strictly pursuant to the current national legislation (Act No. 201/2012 Coll. on air protection, as amended, and Decree No. 330/2012 Coll. on the method of assessment and evaluation of ambient air pollution levels and on the extent of informing the public about levels of ambient air pollution and during smog situations) and pursuant to the requirements of the European Union. The evaluation is carried out with regard to the protection of human health and with regard to the protection of ecosystems and vegetation. Map results are a necessary prerequisite for the indication of areas exceeding the limit values with regard to the protection of human health, for which programmes aimed at the improvement of ambient air quality or regulatory codes are required by the legislation.
The yearbooks on ambient air quality are primarily intended for bodies and organizations concerned with environmental issues and ambient air protection in the Czech Republic. They are periodically provided to state administration bodies, to all contributors to the AQIS database and to further selected entities. Each yearbook is publicly available on the website of the CHMI at www.chmi.cz.
I.2 POLITICAL AND LEGISLATIVE FRAMEWORK OF AMBIENT AIR QUALITY
The extent of air pollution is objectively ascertained by monitoring concentrations of ambient air pollutants (air pollution monitoring) in the ground layer of the atmosphere within a network of measuring stations (Fig. I.1; for more details, see Chapter XI). Limit values have been set for pollutants that are monitored and evaluated with regard to provable harmful effects on human health or on vegetation and ecosystems. Air quality evaluation mainly entails comparisons between recorded concentrations of pollutants and their respective limit values (Tabs. I.1 and I.2) permissible frequencies of their exceedance, i.e. concentrations levels which should not be exceeded pursuant to applicable legislation.
The basic strategic document of the EU in the field of ambient air quality assessment and management is the Thematic Strategy on Air Pollution (hereinafter the Strategy). The objective of the Strategy, in accordance with the 6th Environment Action Programme, is to achieve ‘the level of ambient air quality which does not give rise to the risks for human health and the environment and does not have markedly negative impacts on them’. Based on the 2005 Strategy, the European Commission carried out a review of the current EU policy in the field of ambient air protection. This resulted in the adoption of a package of measures (Clean Air Policy Package) in December 2013. The package contains, for instance, the programme document ‘Clean Air for Europe’ outlining new objectives concerning ambient air quality for the period up to 2030, a draft of a revision of the directive on national emissions ceilings with stricter national emissions ceilings for six major pollutants, or a draft of a new directive on the reduction of pollution caused by medium-sized combustion sources (EC 2013a).
Within the EU framework, the main tools for the protection and improvement of ambient air quality include: Directive 2008/50/EC on ambient air quality and cleaner air for Europe, Directive 2004/107/EC relating to arsenic, cadmium, mercury, nickel and polycyclic aromatic hydrocarbons in ambient air, Directive 2001/81/EC on national emission ceilings for certain atmospheric pollutants, and European Parliament and Council Directive No. 2010/75/EU on industrial emissions (integrated prevention and pollution limitation).
The national legislation on air quality evaluation in the Czech Republic is harmonized with the European legislation. Act No. 201/2012 Coll. on air protection, as amended (hereinafter the Air Protection Act) defines among others the zones and agglomerations for ambient air quality evaluation. The details are specified in Decree No. 330/2012 Coll. on the method of assessment and evaluation of ambient air pollution level, on the extent of informing the public on the level of ambient air pollution and during smog situations.
Zones and agglomerations are primarily understood as basic units for air quality management. The Air Protection Act defines three agglomerations – the agglomeration of Prague, the agglomeration of Brno and the Ostrava/Karviná/Frýdek-Místek agglomeration – and seven zones (Fig. I.2).
The yearbook presents an evaluation of air quality in the year 2014 pursuant to the requirements of the Czech legislation on air quality protection. In accordance with the Air Protection Act, the evaluation is aimed at defining areas with exceedances of limit values for the protection of health and the protection of ecosystems and vegetation. Whenever a limit value is exceeded in a zone or agglomeration or if the limit value is exceeded in a zone or agglomeration more times than the set maximum number of exceedances, the Ministry of the Environment is obliged to develop, in cooperation with the respective regional or local authority, a programme aimed at the improvement of air quality for the given zone or agglomeration within 18 months following the end of the calendar year in which the limit value was exceeded. During the preparation of each programme, the Ministry adopts such measures to ensure that the limit value is met as soon as possible.
Limit values are based on recommended (guideline) values set by the World Health Organization (WHO) on the basis of a number of epidemiological studies (Table I.3). In order to protect public health, the WHO recommends maintaining pollutant concentrations at levels that are lower than those at which negative effects on human health are documented. Nevertheless, these values stem from conclusions regarding the health effects of ambient air pollution and do not take into account the issues of technical and economic feasibility and further political and social factors. Therefore, limit values set by the legislation may be higher, but the process heading towards the meeting of the WHO guideline values must generally be supported (WHO 2013). The 2014 issue of this yearbook for the first time also presents certain imission characteristics referring to values recommended by the WHO. A separate annex (Annex IV) is dedicated to the mapping of concentrations of pollutants with the indication of levels recommended by the WHO for the protection of human health.
I.3 AMBIENT AIR POLLUTANTS AND THEIR EFFECTS
Ambient air pollution is one of the factors which affect human health. Air pollution can manifest itself by the occurrence or worsening of subjective symptoms or by objective health disorders, which may be partially caused by exposure to substances contained in ambient air, especially through the respiratory tract (SZÚ 2014).
Health effects may include slight temporary changes in the respiratory tract and impaired pulmonary function, reduced performance, the need to find first aid, hospitalization or even death. There is growing evidence that air pollution adversely affects not only the respiratory system, but also the cardiovascular system. Some pollutants have carcinogenic effects, influence the functioning of endocrine glands, or affect foetal development and growth (SZÚ 2013a).
As mentioned above, ambient air pollutants have negative effects also on vegetation and ecosystems. Many pollutants have the ability to accumulate in the environment or cause damage to materials and buildings.
Fig. I.1 Major station networks of ambient air quality monitoring, 2014
Fig. I.2 The zones and agglomerations for ambient air quality assessment and evaluation of ambient air pollution level according to the Act No. 201/2012 Coll. on Clean Air Protection, as amended
1 Eutrophication is the process whereby the environment is enriched by nitrogen and phosphorus. Acidification is the decrease in pH.