The aim of this study was (a) to determine the concentration of fluoride and cadmium in urine of 1240 children ( 635 boys, 605 girls) from Gda¨˝sk, aged 7-14; and (b) to examine whether a correlation exists between age and sex of children, the location of the schools, and the urinary levels of fluoride and cadmium. Fluoride was determined potentiometrically using a fluoride-specific electrode. Cadmium was determined by atomic absorption spectrometry. The mean fluoride concentration in urine in children attending two schools located close to a phosphate fertilizer waste disposal site was 2.14 ĄŔ 1.16 mg FĄĄ/L, in three others 1.05 ĄŔ 0.49 mg FĄĄ/L. The mean cadmium concentration in urine was 0.17 ĄŔ 0.19 ŚĚg Cd/L. In children aged 7 the cadmium concentration was significantly lower than in older ones.