Amounts and sources of fluoride in precipitation over southern Norway

Fluoride is a ligand which forms complexes with Al3+ in natural waters with relatively low pH. It is not well established the extent to which fluoride in precipitation is primarily recycled from sea water, derived from dust or volcanic emissions or has an anthropogenic origin. The average concentration of F− as determined by ion chromatography assuming no interference with simple organic acids in over five hundred samples of precipitation collected at four sampling stations in southern Norway in 1983, is 20 μg −1. A comparison of the concentrations and amounts of fluoride measured in the precipitation samples with internally consistent measurements of other components such as Cl−, Br−, and SO42− on the same samples using correlation analysis, indicates that a major portion of the fluoride, i.e. more than 90%, have a non-marine origin.