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The peculiarities of the aerosol particle deposition in the human respiratory tract depending on the particle size and the breathing rate have been analysed. The highest deposition efficiency (0.85) was determined for the largest particles (10-20 µm) and the lowest efficiency (0.28) for the finer particles (0.3 µm). The heavy metal amount penetrating into the human respiratory tract at a different breathing rate in Vilnius has been evaluated. It has been determined that the deposition efficiency of heavy metals in the human respiratory tract changes insignificantly with the increase in the breathing rate, and when the breathing rate increases threefold (from 10 to 30 L min −1 ) the efficiency decreases only by about 10%. On the average, about 60% of heavy metals in the inhaled air penetrate into the respiratory tract. The comparison of Pb, V, and Zn concentrations in Vilnius city with those at the Preila background station has shown that they differ up to two times. It means that the contribution to the pollution with these metals in Vilnius city is insubstantial, and there is no considerable threat to human health.

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The concentrations of heavy metals Pb, Cd, Cu, Zn and Hg, benzo[a]pyrene and oil products (C 15 -C 28 ) in bulk (wet and dry) atmospheric deposition in Vilnius city in 2005-2006 were analysed. The highest flux to the ground surface of the city residential area, reaching 1,680 mg m −2 year −1 , was determined for oil products, which in atmospheric bulk deposition was estimated to be mainly in the form of solid sediments. Among heavy metals, the highest flux was determined for Zn (113.5 mg m −2 year −1 ), while the lowest flux was determined for Hg (0.06 mg m −2 year −1 ). The flux of investigated pollutants ranges from a few times, or for some pollutants, up to one order of magnitude higher at the urban sampling site in comparison to residential or background sites. Some hundred tons of oil products, approximately 52 tons of zinc and a considerably lower amount of mercury, benzo[a]pyrene and cadmium deposit yearly to the ground and water surface of Vilnius city. Metallic constructions related to transport and buildings, automobile exhausts, spills of fuel and lubricants are suggested to be the factors which result in the accumulation of high amounts of heavy metals, oil products and other pollutants on the ground surface of the city.