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USGS · 70021941

Effects of humic substances on the bioconcentration of polycyclic aromatic hydrocarbons: Correlations with spectroscopic and chemical properties of humic substances

Abstract

The presence of dissolved humic substances (HS, fulvic and humic acids) generally reduces the up take of hydrophobic organic compounds into aquatic organisms. The extent of this effect depends both on the concentration and on the origin of the HS. The aim of this study was to investigate the role of qualitative differences between HS from different origins. The effects of seven different HS on the bioconcentration of pyrene and benzo[ a ]pyrene (B a P) in the nematode Caenorhabditis elegans were related to the spectroscopic and chemical properties of the HS. The effect of each humic material on the bioconcentration of pyrene or B a P was quantified as a “biologically determined” partition coefficient K DOC . We observed significant linear relationships between K DOC and the atomic H/C ratio, the specific absorptivity at 254 nm, the content of aromatic carbons (as determined by 13 C nuclear magnetic resonance spectroscopy, the copper-complexing capacity, the content of phenolic OH groups, and the molecular weight of the HS. There was no discernible relationship of K DOC with the atomic (N + O)/C ratio, an indicator of the polarity of HS. Taken together, our results show that the variability in the effects of HS from different origins could be related to variations in bulk properties of the HS. Parameters describing the aromaticity of the humic materials seemed to be most useful for estimating effects of HS on the bioconcentration of pyrene and B a P.

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BibTeXRIS

M. Haitzer, G. Abbt-Braun, W. Traunspurger, C.E.W. Steinberg. 1999-12-01. Effects of humic substances on the bioconcentration of polycyclic aromatic hydrocarbons: Correlations with spectroscopic and chemical properties of humic substances. https://doi.org/10.1002/etc.5620181219

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