The study was designed to determine asymptomatic lead poisoning prevalence and cadmium exposure of preschool children living in a coal-mining area in Yatagan, Mugla, Turkey. The research was conducted between May and June 2002. The study included 236 children (53.4% female and 46.6% male) who were identified among the healthy children between the ages of 6 months and 6 years, using a systematic sampling method, from the records of the local medical centre of Yatagan. Assessments of the levels of blood lead and cadmium were performed by an atomic absorption spectrophotometer, in the Department of Biophysics, Cerrahpasa Medical Faculty. The mean age of females and males were 49 +/- 18 and 43 +/- 19 months, respectively. The mean blood lead level was 33.8 +/- 15.6 mu g/dL in females and 38.8 +/- 16.0 mu g/dL in males. The mean blood lead level of the males was significantly higher than the females (P < 0.05). Correlation analysis showed a statistically significant negative correlation between blood lead level and age in both sex groups (r= -0.367, P < 0.001). The blood lead level was found to be > 10 mu g/dL in 95.7% and > 20 mu g/dL in 87.6% of all children. The mean blood cadmium level of all children was 1.31 +/- 0.72 mu g/dL. The blood cadmium level was found to be > 0.5 mu g/dL, which is considered to be toxic, in 85% of all children. The difference in blood cadmium levels between sexes was not significant. A statistically significant negative correlation was found between blood cadmium level and age of all children (r= -0.382, P < 0.001). Although it is not possible to understand from this study what proportion of the biological lead and cadmium burden results from mining waste and what proportion comes from other sources, such as paint and gasoline residue deposited in soil and air, these results do indicate that asymptomatic lead poisoning and cadmium exposure are significant problems in children living in the Yatagan area. In conclusion, environmental lead measurements (house dust, soil, drinking water and air) must be performed, the results must be compared with the normal limits, and precautions must be taken if necessary in the Yatagan area. Future public health research efforts should focus on reducing the excessive levels of lead and cadmium in the environment.