EN
The objective of the work was to explain to what degree fluorine bioaccumulation is conditioned by the high level of industrialisation in Central Pomerania depending on the distance of a farm from the place of contamination emission in the trophic system: soil - plant - animal. Soil, feed, and horsehair and blood samples were taken from each level of the system. Material sampled from 48 crossbred horses was divided into three age groups: group 1 - horses aged 7 years and below, group 2 - horses aged between 7 and 15 years, and group 3 - horses aged over 15 years. Fluorine measurements in the soil, feed, and examined tissues were taken by means of an ion-selective electrode combined with an ORION ion meter. An elevated soil acidity in zone I, in the mouth of the Vistula River, stretching 50 km west of the place of contamination emission, increased the level of this element in the soils of the examined area, as well as in feeds offered to horses, compared with zone, II located in the mouth of the Leba and the Slupia Rivers, 80 to 100 km to the west of the place of contamination emission. A significantly higher average fluorine concentration in the blood and hair of horses raised in zone I, compared with zone II, was found. This concentration was the highest in the youngest animals. Fluorine accumulation in the blood and in the hair of horses raised in zone II was found to increase as the animals grew. Monitoring of fluorine bioaccumulated in soil, feed, blood, and the hair of horses may be a useful indicator of fluorine contamination in the natural environment.