Carbon Isotope Signature of Polycyclic Aromatic Hydrocarbons (PAHs): Evidence for Different Sources in Tropical and Temperate Environments?
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- 作者：Wolfgang Wilcke ; Martin Krauss ; and Wulf Amelung
- 刊名：Environmental Science & Technology
- 出版年：2002
- 出版时间：August 15, 2002
- 年：2002
- 卷：36
- 期：16
- 页码：3530 - 3535
- 全文大小：119K
- 年卷期：v.36,no.16(August 15, 2002)
- ISSN：1520-5851
文摘
In tropical soils, naphthalene and, partly also, peryleneoccur at elevated concentrations while pyrolytic highermolecular weight PAHs are almost absent. We hypothesizethat there are recent biological PAH sources in thetropical environment related with woody plants and termites.We used the C isotope signature of individual PAHs intemperate and tropical soils and in tropical wood and termitenests to distinguish different PAH sources. The mean
13C values of the benzo[b+j+k]fluoranthenes and of benzo[a+e]pyrenes in temperate soils ranged between -24.6”and -25.3”, being similar to values reported in theliterature for PAHs with pyrolitic origin. The mean 13Cvalues of perylene decreased in the order temperate soils(-27.0”) > termite nests (-31.4”) > tropical soil(-32.4”), while those of naphthalene (-24.6” to -26.2”)were similar among the tropical and temperate soils,tropical wood, and termite nests. Our results support theassumption that perylene in the tropical environment isrecently biologically produced, as indicated by the depletionin 13C. The C isotope composition of naphthalene, however,cannot be used to distinguish different sources.
13C values of the benzo[b+j+k]fluoranthenes and of benzo[a+e]pyrenes in temperate soils ranged between -24.6”and -25.3”, being similar to values reported in theliterature for PAHs with pyrolitic origin. The mean 13Cvalues of perylene decreased in the order temperate soils(-27.0”) > termite nests (-31.4”) > tropical soil(-32.4”), while those of naphthalene (-24.6” to -26.2”)were similar among the tropical and temperate soils,tropical wood, and termite nests. Our results support theassumption that perylene in the tropical environment isrecently biologically produced, as indicated by the depletionin 13C. The C isotope composition of naphthalene, however,cannot be used to distinguish different sources.