Chemical speciation of polycyclic aromatic hydrocarbons in sediments: partitioning and extraction of humic substances.
The primary objective of this study was to examine the chemical speciation of polycyclic aromatic hydrocarbons (PAHs) found in sediments endowed with different characteristics. To achieve this purpose and because the nature of the sediments influences the distribution of PAHs, we have analyzed four different types of sediments. To study the role of organic matter in the sequestration of PAHs, we fractionated humic substances into humic acids and humin-mineral fractions. After their separation and purification, the humic components were examined for their sorptive reactivity by extracting them with organic solvents; these extracts were subsequently subjected to GC/MS analysis. Our results show that PAHs are distributed between labile and sequestered fractions in sediments. A slower uptake of PAHs occurs when the sequestered fraction is formed, and this process can be prolonged and may be influenced by the characteristics if the sediment. Our study suggests that organic contaminants are available in muddy sediments for a longer period of time than in sandy sediments.
Orecchio
Santino
S
Dipartimento di Chimica Inorganica ed Analitica S. Cannizzaro, University of Palermo, Viale delle Scienze, pad. 17, 90128 Palermo, Italy. orecchio@unipa.it
Mannino
Maria Rosaria
MR
D005591:Chemical Fractionation; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D019015:Geologic Sediments / Q000737:chemistry*; D006812:Humic Substances; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000737:chemistry*; D052616:Solid Phase Extraction
D006812:Humic Substances; D011084:Polycyclic Aromatic Hydrocarbons