skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Apparent stimulation of tree growth by low ambient levels of fluoride in the atmosphere

Journal Article · · J. Air Pollut. Control Assoc.; (United States)

Fluoride emissions from the aluminum smelter of Kitimat, British Columbia have been affecting the adjacent forests since 1954. A review is given of this study conducted from 1954 to 1979. The effects were determined on the foliage analysis, lichen growth, observed plume/air flow and topography. The trees in the plots were measured and recorded by species, diameter, height, and condition. The areas of forest exposed to a very low level of fluoride in the ambient air showed growth rates higher than expected under normal conditions. The effect of the emissions in the inner zone was to reduce the growth rate by 28.1%. The growth rate of the outer zone was reduced by 19.0%. The surround zone showed a small loss of growth at 2.2% At the 1979 remeasurement of the growth from 1974 to 1979, it was found that growth reduction in the inner zone had continued, but the outer and surround zones now showed increases in growth of 2.8% and 13.6% respectively. During the period 1974-1979, the rate of fluoride emission of the smelter had been reduced by 64% of what it had been in the preceding period. It is possible that certain low levels of fluoride may stimulate tree growth without prior injury by higher levels of fluoride. Analysis of results following 1984 remeasurement of sample trees may provide greater understanding of this situation. 1 figure, 1 table.

Research Organization:
Reid, Collins, and Associates, Ltd., Vancouver, British Columbia
OSTI ID:
5759526
Journal Information:
J. Air Pollut. Control Assoc.; (United States), Vol. 35:1
Country of Publication:
United States
Language:
English