The Environmental and Health Monitoring program in the large cities of Lithuania is aimed at the evaluation of the population health status in terms of chemically induced diseases. During the 1991 to 1995 period, this program was carried out in two Lithuanian cities, Vilnius, the capital of the country, and Siauliai. Data on the chemical pollution of ambient air, soil, and drinking water and the morbidity were mapped. Risk zones of environmental pathology threat were defined within each city on the basis of the mapped data. Subsequently, chemical pollutants, namely, heavy metals and benz(a)pyrene, were determined in the biomedia of selected population groups in the risk zones. Exposure analysis of heavy metals (Pb, Cd, Ni, Cr, Cu, Zn) and benz(a)pyrene was carried out for standardized groups of children and pregnant women in the risk zones and in a relatively safe (control) zone. The evaluation of exposure to heavy metals was based on the levels found in blood, urine, and hair. Benz(a)pyrene was tested in urine samples. The obtained data are applied in the process of environmental health monitoring in the large cities of Lithuania.