POLYCHLORINATED DIBENZO-PARA-DIOXINS AND DIBENZOFURANS ASSOCIATED WITH WOOD-PRESERVING CHEMICAL SITES - BIOMONITORING WITH PINE NEEDLES

Gas chromatography-mass spectrometry (GC-MS) analysis of pine needle extracts from two pentachlorophenol wood-preserving sites detected relatively high overall concentrations of polychlorinated dibenzo-p-dioxins (PCDDs; 1798 and 935 ppt) and dibenzofurans (PCDFs; 310 and 141 ppt). The dominant congener was octachlorodibenzo-p-dioxin (Cl8DD), the SIGMA-PCDDs > SIGMA-PCDFs, and relatively low levels of the tetra- and pentachlorodibenzofurans (SIGMA-Cl4DFs and Cl5DFs) were detected. This pattern was similar to that observed for the PCDD and PCDF contaminants detected in commercial pentachlorophenol and significantly different from the pattern observed for combustion-derived PCDDs and PCDFs. The levels of these compounds were significantly lower in two "pristine" areas in the Kootenai National Forest and the Glacier-Waterton International Peace Park (i.e., SIGMA-PCDDs was < 10.8 and 9.22 ppt; SIGMA-PCDFs was < 2.65 and < 1.31 ppt). There was a rapid decrease in the total PCDD and PCDF levels in pine needles with increasing distance from one of the pentachlorophenol wood-preserving sites. These data suggest that pine needles can be used as a biomonitor for emissions of PCDDs and PCDFs from wood-preserving chemical sites.