ABOUT THE FORMS OF OCCURRENCE OF PU IN HO T PARTICLES

''Hot particles'' collected in 1987-1988 within 30-km zone around Cher nobyl NPP were different in radionuclide composition and Pu fractionat ion coefficients, Ru-106 and Cs-137 as compared to Ce-144. Pu was foun d in ''hot particles'' in different forms. The particles with composit ion close to nuclear fuel exhibit the minimum Pu solubility. A positiv e correlation between unsoluble Pu and Ce-144 was found in the particl es. Maximum Pu solubility was found in the particles enriched in Ce-14 4 (only 17-32% of unsoluble Pu). A conclusion has been made that high amounts of soluble forms of Pu in ''hot particles'' (up to 30-40%) can leave these particles to involve in biological cycles. A possible com position of ''hot particles'' formed as a result of solid state conden sation of gas-vapor cloud and mechanisms of insertion of radionuclides into these particles were