Air quality significantly affects the environment, human health, as well as the various ecosystems. The 1970s and 1980s in Slovakia were associated with high sulphur emissions. Heavy metals emissions (lead, cadmium) increased in some regions. Average concentrations of tropospheric ozone grew. Acidification and atmospheric pollution caused various environmental problems and had negative impacts on human health.

Since 1990, a very positive development with regard to local and regional air quality in Slovakia has been recorded as a result of transformational and restructuring processes in the Slovak economy (which were connected with the reduction in economic activities) as well as restructuring of industry, gradual increase in energy efficiency, growth in gas consumption, and the adoption of new legislation.

Nowadays, cross-border emissions significantly contribute to air pollution in Slovakia. In cities and surrounding areas, air pollution caused by particulate matter (PM₁₀) is currently the main problem.

Since 1990, Slovakia has made progress in reducing many forms of air pollution in order to protect human health and ecosystems. A range of limit and target values have been implemented to ensure protection, e.g. in the Act No 137/2010 Coll. of the Law on Air protection.

Air pollution in urban areas

The whole territory of the Slovak republic was divided into zones and agglomerations and, on the basis of air assessments in each zone/agglomeration, monitoring regimes were defined. Results from monitoring of urban areas showed that air pollution caused by particulate matter (PM₁₀) is currently the main problem still causing human health problems in many cities and surrounding areas. In 2009, the daily limit value was exceeded at 15 of 32 stations. In Figure 1, the number of exceedances of the daily limit PM₁₀ value at selected monitoring stations in Slovakia is shown.

In 2009, no agglomeration showed exceeded levels of sulphur dioxide (SO₂) in hourly or daily values beyond the public health limit (125 μg SO₂.m^-3). The annual limit value for human health of nitrogen dioxide (NO₂) (40 μg NO₂.m^-3) was exceeded only at two station. However, no station showed any exceedance of the limit value beyond the tolerance threshold (see Figure 2).

At present, the carbon monoxide (CO) pollution level is relatively low and the limit value is not exceeded at any monitoring station. Air pollution by lead and other heavy metals do not pose a major risk in Slovakia; concentrations do not exceed the upper threshold evaluation limit.

Link to EEA CSI:

http://themes.eea.europa.eu/IMS/ISpecs/ISpecification20080701123452/IAssessment1219309276318/view_content

Link to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=2&id_indikator=2488#

Tropospheric ozone

Average concentrations of tropospheric ozone in Slovakia grew during the years 1973–90 by approximately 1 μg.m^-3 per year. After 1990, no significant trend in average concentrations has been recorded. In Figure 3, the annual average ozone (O₃) concentration at selected monitoring stations in Slovakia is shown.

Link to EEA CSI:

http://themes.eea.europa.eu/IMS/ISpecs/ISpecification20091007131526/full_spec

Link to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=303&id_indikator=2685

In Figure 4, the number of exceedances of the ozone target value for the protection of human health (8 h mean 120 μg.m^–3) is shown, averaged over 2007–09 (the target value must not be exceeded on more than 25 days per calendar year averaged over three years).

Link to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=2&id_indikator=454#

Regional air pollution

Regional air pollution is monitored at four monitoring station in Slovakia. In 2009, results showed that concentrations of sulphur dioxide, sulphates, nitrogen oxides and nitrates were not exceeded at any regional station.

The main sources contributing to air pollution are incineration processes, industry, transport and agriculture.

Since 1990, a significant decrease in air emissions has been reported in Slovakia. During the period 1990–2008, a reduction of 87 % in SO₂ emissions was reported as a consequence of a reduction in energy production and consumption, and to the use of better quality and more purified fuels.

Over the same period, a 57 % decrease in NOx emissions was due mainly to technical and technological improvements in the incineration process and denitrification. A significant decline in nitrogen oxides emissions was achieved in mobile sources, mainly in road transport (see Figure 5).

Link to EEA CSI:

http://themes.eea.europa.eu/IMS/ISpecs/ISpecification20081014122413/IAssessment1226069684950/view_content

Links to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=303&id_indikator=3505

http://enviroportal.sk/indikatory/detail.php?kategoria=303&id_indikator=3525

Non-methane volatile organic compounds, persistent organic particles and heavy metal emissions have been also decreasing since 1990.

Link to EEA CSI:

http://themes.eea.europa.eu/IMS/ISpecs/ISpecification20081014123013/IAssessment1226322854001/view_content

Link to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=303&id_indikator=2565

Slovakia is a signatory to the UN Economic Commission Convention on Long-range Transboundary Air Pollution and its Protocols: the Protocol on further reduction of sulphur emissions and the Protocol on the reduction of acidification, eutrophication and ground ozone. Slovakia is on track to achieve, by 2010, the specific objectives in accordance with the Protocols and in accordance with Directive 2001/81/EC on national emission ceilings for certain atmospheric pollutants. National emission ceilings for the Slovakia to be achieved by 2010 are as follows:

•  sulphur dioxide (SO₂): 110 kt

Link to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=303&id_indikator=497

• nitrogen oxides (NO_X): 130 kt

Link to Enviroportal - Environmental Indicators (in Slovak):

http://enviroportal.sk/indikatory/detail.php?kategoria=303&id_indikator=507

• volatile organic compounds (VOC): 140 kt
• ammonia (NH₃): 39 kt

Air protection has been secured, in addition to the obligations of the Convention on Long-range Transboundary Air Pollution and its Protocols, in the corresponding Slovak policy documents (e.g. strategies, principles and priorities of the State environmental policy, National Environmental Action Programme I., II., and action plans) to ensure air quality.

The corresponding EU air protection legislation — the Air Quality Framework Directive was transposed into Slovak legislation, mainly into Act No 137/2010 Coll. of the Law on Air protection.