RADIOACTIVITY IN AIR AROUND NUCLEAR-FACILITIES IN MEXICO

Radioactivity in air sampled around the Nucleoelectric Power Plant at Laguna Verde and the Nuclear Center of Mexico research laboratories wa s analyzed. The gross beta activity in air filters during the preopera tional (1986-1989) and operational (1989-1992) periods of the plant sh owed stability except in May 1986 when a contribution from the Chernob yl accident was observed. The radionuclides in air were below the acce pted operational limit in the whole period. The average gross beta con centration in air during the same period (1986-1992) at the Nuclear Ce nter showed also the higher values in 1986 and the concentration value s of Cs-137 determined in composite samples of edible wild mushrooms c ollected at this site, exhibited an increase in the same year. An anal ysis of the synoptical meteorological large-scale pattern occurring in the Northern Hemisphere after the Chernobyl accident is presented in order to estimate how the radioactive plume arrived to Mexico.