Evaluation of cumulative air pollution in Riga and Liepaja...

Introduction Air pollution is one of the most actual environmental problems in the world. Increasing traffic density and energy consumption lead to increased pollution causing substances emissions in ambient air. It is a significant risk factor for multiple health conditions including lung cancer, respiratory and heart diseases. Therefore it is important to keep up with latest data about actual air quality to react timely and initiate appropriate environment management procedures when pollution levels rise to high (Snyder et. al, 2013). For this purposes, air quality monitoring is carried out. It is regular and continuous collecting of information about air quality to prevent with pollution associated hazards. Usually as monitoring technical solution automated measurement stations are used. They measure concentrations of various substances in air in nonstop mode – ranging from gaseous pollutants, like nitrogen oxides (NOx) and ozone, to particulate matter. Results are compared to according normative to determine if actual pollution is threat or not. However, one thing is to control individual substances – other is actual impact, caused by synergy of different pollutants and environment factors. Latest research shows that there are hidden threats called cumulative effect – synergy between different pollutants and environmental factors which produce greater impact on living organisms than same substances in separate action. For example, ozone mixing with other pollutants