The results of studies of the lead and silver content in water bodies and air and the ice nuclei concentrations in the regions subjected to hail protection in the Republic of Moldova in 1977÷1991 are summarized. Until 1983, hail-hazardous clouds were seeded mostly with crystallizing pyrotechnic compositions based on lead iodide; subsequently, silver iodide was used. The problem of environmental pollution in the regions involved in the activities using various crystallizing reagents based on heavy metals are discussed. Accumulation of these metals depending on the type and lifetime of the reagents used is estimated. Long-term observations of the use of AgI-based ice-forming compositions have not revealed either a tendency of silver aerosol accumulation in the ground air or its correlation with the amount of the consumed reagent. The analysis of results clearly show that there are no environmentally harmful effects arising from hail-suppression cloud seeding program involving silver iodide aerosols in Moldova.