Distribution of Soil Fluorides Near an Airborne Fluoride Source

Abstract

AbstractThe purpose of the study was to determine the effect of a major source of airborne fluorides on the geographical distribution of total fluoride in soils. Total fluoride determinations were made on soil samples collected from the same pastures at different distances from the source in spring and fall of 1973 and 1974. Samples were collected at depths of 0–5, 5–15, and 15–30 cm. Forage fluoride levels were used to determine areas of relatively high and low airborne fluoride impact, and soil sampling locations within these respective areas were segregated accordingly. Total soil fluoride increased with depth at low fluoride impact sites, but decreased with depth at high impact sites. This was a result of significantly (p = 0.05) elevated fluoride levels at the 0–5 cm depth on high impact sites compared to low impact areas. Total soil fluoride for all depths decreased with distance from the fluoride source, and approximated background levels at about 10 km. It is concluded that the observed magnitude of atmospheric fluoride contribution to total soil fluoride will probably have no significant impact on agriculture.