Ba. Bonn, POLYCHLORINATED DIHENZO-P-DIOXIN AND DIBENZOFURAN CONCENTRATION PROFILES IN SEDIMENT AND FISH TISSUE OF THE WILLAMETTE BASIN, OREGON, Environmental science & technology, 32(6), 1998, pp. 729-735
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) are highl
y hydrophobic compounds that have been implicated as carcinogens and,
more recently, as estrogen disrupters. An occurrence and distribution
study of these compounds in the Willamette Basin, Oregon, was conducte
d by the U.S. Geological Survey as part of the National Water-Quality
Assessment Program. Bed sediment was collected from 22 sites; fish tis
sue was collected from eight sites. PCDD/F were found to be ubiquitous
in Willamette Basin sediment. A distinct homolog profile, dominated b
y octachlorodibenzo-p-dioxin, was observed in sediment throughout the
basin. The PCDD homolog profile was consistent at all sites, regardles
s of total PCDD/F concentration, presence of point sources, subbasin s
ize, geographic location or land use. Principal components analysis re
vealed a gradient among the homolog profiles that showed increasing do
minance of highly chlorinated congeners where human and industrial act
ivity increased. Tissue and bed sediment obtained from the same site d
id not have similar PCDD/F concentrations or homolog profiles. Fish ti
ssue showed enrichment in less chlorinated congeners and congeners wit
h chlorine substitutions in the 2, 3, 7 and 8 positions.