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Naturalne i sztuczne skażenia atmosfery globu.

Jaworowski Zbigniew

Wiadomości Chemiczne

1999

[Z] 53, 9-10

701-723

Results of determination of natural radionuclides, fission products and heavy metals in contemporary and pre-industrial ice from 14 glaciers in Southern and Northern Hemisphere, and in aerosols collected during three decades from seven altitudes between o and 15 km in the troposphere and stratosphere, were used for determinations of fluxes of man-made and natural pollutants into the global atmosphere. For these determinations 137Cs from nuclear explosions and natural 210Pb were used as tracers. Concentrations of natural radionuclides and heavy metals in ice deposited before industrial revolution were higher than in contemporary precipitation preserved as firn in high mountain and polar glaciers. This was due probably to volcanic activity which was higher before the first part of the 20th century. Man-made contribution to the total atmospheric flux is now 3,5% for 226Ra, 12% for U, 7,4% for Pb. 0,11% for Cd, 62% for V and 5,8% for Hg. The mass of annual global wet precipitation, determined for the first time with radioactive tracers, is 5,7ˇ10(17) kg. In Poland, the lowest concentration of stable lead in human bones is now in highly industrialized southern districts. Lead level in medieval human bones from these districts reached up to 370ug/g. Its current average level in inhabitants of southern Poland is 3,5 ug/g, i.e. similar as 1800 years age.