Investigation of the solvent extracts of humic organic matter (HOM) isolated from the Ravenna Lagoon to study environmental pollution and microbial communities.
Solvent extracts of HOM isolated from highly polluted sediments from the Ravenna Lagoon were studied. Diagnostic indicators included polycyclic aromatic hydrocarbons (PAHs) and nonylphenols as hazardous organic pollutants to characterize anthropogenic pollution, as well as fatty acids (FA, analysed as methyl esters, FAME) to characterize microbial communities responsible for natural attenuation processes. The distribution of PAHs including cyclopentafused surrogates pointed to a significant pyrogenic origin, characteristic for methane combustion. The PAH distribution was characterized by high concentrations of highly carcinogenic analytes with molecular weights of 276Da (benzo[ghi]perylene prevailing) and 300Da (coronene prevailing). The PAH pattern as obtained by solvent extraction was very different from that obtained from pyrolysis/thermochemolysis of the HOM polymeric matrix. The FA pattern indicated strong bacterial input, with a significant contribution from methanotrophic bacteria as revealed by monounsaturated members with n:1omega8 and n:1omega5 double bonds in the alkyl chain. Terrestrial inputs as revealed by FAME analysis beyond C(20) with pronounced even-over-odd discrimination were of minor significance. This was confirmed by the pattern of nC(24)-nC(30) alcohols in strong even-over-odd prevalence occurring in relatively low concentrations. The hopane hydrocarbon distribution reflected a distinctive impact from industrial processes utilizing heavy fractions of petroleum as feedstock. Hopanols along with the 17beta(H),21beta(H)-bishomohopanoic acid pointed to hopane producers, including methanotrophic and sulfate-reducing bacteria. Nonylphenols, which could not be detected in the pyrograms of solvent-extracted HOM matrix, had a total concentration of about 70microg g(-1) referred to the HOM in the solvent extract. In addition to common phytosterols including beta-sitosterol, coprostanol could be detected in the solvent extracts pointing to human fecal matter contamination. Concentration of resin acids turned out to be very low, thus no harmful environmental effects are to be expected from these compounds.
UFZ-Helmholtz Centre for Environmental Research Leipzig-Halle, Department of Environmental Technology, Permoserstr. 15, 04318 Leipzig, Germany. juergen.poerschmann@ufz.de
Juergen
J
Poerschmann
Daniele
D
Fabbri
Tadeusz
T
Górecki
D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D019015:Geologic Sediments / Q000032:analysis / Q000382:microbiology; D006358:Hot Temperature; D006812:Humic Substances / Q000032:analysis*; D007558:Italy; D010636:Phenols / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012997:Solvents / Q000737:chemistry*; D014871:Water Microbiology / Q000592:standards
D004785:Environmental Pollutants; D005227:Fatty Acids; D006812:Humic Substances; D010636:Phenols; D011084:Polycyclic Aromatic Hydrocarbons; D012997:Solvents; C025256:nonylphenol