Background 

The growing public health concern caused by non-communicable diseases in urban surroundings cannot be solved by health care alone; therefore – a multidisciplinary approach is mandatory. This study aimed to evaluate the airborne aerosol pollution level in primary schools as possible factor influencing origin and course of the diseases in children.

Methods 

Seasonal aerosol particle number concentration (PNC) and mass concentration (PMC) were studied in the randomly selected eleven primary schools in the Lithuanian capital, Vilnius, as model of a middle-size Eastern European city. Total PNC in the size range from 0.01 to >1.0 μm in diameter was measured using a condensation particle counter. Using an optical particle sizer, PNC was measured and PMC estimated for particles from 0.3 to 10.0 μm. A descriptive statistics was used to estimate the aerosol pollution levels.

Results 

During all seasons, local cafeterias in the absence of ventilation were the main sources of the elevated levels of indoor PMC and PNC (up to 97,500 particles/cm³). The other sources of airborne particulates were the children's activity during the lesson breaks with PMC up to 586 μg/m³. Soft furniture, carpets in the classrooms and corridors were responsible for PMC up to 200 μg/m³. Outdoor aerosol pollution (up to 18,170 particles/cm³) was higher for schools in city center. Elevated air pollution in classrooms also resulted from intermittent sources, such as construction work during classes (200–1000 μg/m³) and petrol-powered lawn trimmers (up to 66,400 particles/cm³).

Conclusion 

The results of our survey show that even in a relatively low polluted region of Eastern Europe there are big differences in aerosol pollution within middle-size city. Additional efforts are needed to improve air quality in schools: more frequent wet cleaning, monitoring the operation of ventilation systems, a ban on construction works during school year, on a use or sandblasting mechanisms in the neighborhood of schools.