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Taking into consideration a unique scenery of the Curonian Spit, dosimetric investigation of ionizing radiation caused by natural radionuclides is performed there. The influence of natural radionuclides present in the ground on the equivalent dose rate of gamma radiation in the ground surface air is established. Measurements of equivalent dose rate are carried out in the whole territory of the Curonian Spit in Lithuania. Especially numerous data have been collected on the coasts of the sea and bay, near them, in seaside dunes and by roads. The established equivalent dose rate values vary from 22 nSv/h (on the dune top) to 90 nSv/h (above an asphalt path). The values of the main gamma radiation source (40K and 226Ra) concentration are measured, and positive correlation of concentrations and equivalent dose rates in the ground surface air between 40K and 226Ra is determinated. It is established that 40K has the biggest influence on equivalent dose rate. The equivalent dose rate values in the ground surface air in the Curonian Spit are comparatively low (they can even be 1630 times lower in comparison to Guarapari beach, Brazil).

Preliminary analysis of the data of ultraviolet (UV) radiation and ground-level ozone concentration measurements from Rugsteliskes Monitoring Station over the years 2002-2003 is presented. Observations showed that an average UV radiation value in January and July of 2002 differed about 10 times. Maximum intensity of UVA radiation was observed in July (about 2,4 W/m2), and minimal one - in December (0,1 W/m2), the highest UVB radiation intensity was in May (0,09 W/m2), while a minimal UVB radiation value as well as that of UVA was registered in December (0,07 W/m2). Relationship between the highest ozone concentration and UVB radiation values during the summer of the investigation period was found to be linear.

The paper covers evaluation of concentration of natural and artificial radionuclides found in the soil and the bottom ground of water reservoirs. It was measured that radionuclide concentration in the soil is bigger than that in the bottom ground of water reservoirs (40K concentration in the ground equals 500 Bq/kg, in the bottom ground - about 200 Bq/kg). Positive correlation was set among all types of radioisotopes. Correlation quotient between artificial radionuclide 137Cs and natural radionuclides amounts to zero.

The paper discusses search of possible pollution sources of natural radionuclides; the measuring method (using the GPS system) of the equivalent dose rate of the environment is introduced; the equivalent dose rate of water reservoirs of Vilnius is measured; the values and variations of equivalent dose rate are evaluated; it is found that the values cover the range from 10 nSv/h to 85 nSv/h; it is noticed that the values measured above water are distinctly less than the equivalent dose rate above the soil surface; comparative analysis between the equivalent dose rate of open water reservoirs of Vilnius and other rivers and lakes of Lithuania is carried out.

A method has been developed that differentiates hydrophobic from hydrophilic submicrometer aerosol particles in air environments containing polydisperse aerosols composed of different chemical species. First, a narrow particle size range is extracted from the polydisperse aerosol by an electrostatic aerosol classifier. Then the monodisperse aerosols of different origins are exposed to preselected supersaturation levels and are size-classified again by a second electrostatic classifier. Hydrophobic aerosol particles pass through the second classifier when its size window matches that of the first classifier. Hydrophilic aerosol particles grow to a larger size and are removed by the second classifier. The method has been applied in the field by measuring the fraction of hydrophobic atmospheric particles in a suburb of Vilnius, Lithuania, during a period of high emission of hydrophobic soot particles from residential coal and industrial oil burning in winter.