Aliphatic and aromatic biomarkers for fingerprinting of weathered
chemically dispersed oil
Received: 12 June 2017 /Accepted: 13 March 2018 / Published online: 25 March 2018
Springer-Verlag GmbH Germany, part of Springer Nature 2018
This study evaluated the applicability of eight types of biomarkers namely, adamantanes, diamantanes, sesquiterpanes, steranes,
terpanes, TA-steranes, MA-steranes, and alkylated PAHs, to characterize chemically dispersed oil (CDO) after the 60-day
weathering. The stability of diagnostic ratios of the selected biomarkers was evaluated and summarized. The results indicated
that the concentrations of biomarkers with low molecular weight, such as adamantanes, diamantanes, and sesquiterpanes, in CDO
were markedly affected by weathering and the associated diagnostic ratios were changed extensively. Most of the alkylated PAHs
were degraded during weathering as well. These biomarkers thus were not recommended for characterizing CDO. The majority
of the terpanes, steranes, TA-steranes, and MA-steranes could be used for weathered CDO fingerprinting due to the relatively
stable diagnostic ratios. The findings could help to identify applicable biomarkers for fingerprinting of weathered dispersed oil.
Chemically dispersed oil
Dispersion is widely used for oil spill response (Lessard
and DeMarco 2000;Prince2015). An oil dispersant main-
ly contains neutral and anionic surfactants in certain ra-
tios, as well as solvents (Prince 2015). It reduces interfa-
cial tension between oil and water by enhancing the gen-
eration of small and stable oil-surfactant micelles (oil in
water emulsion) in the water column (Sorial et al. 2001).
By using dispersants, the oil in a water emulsion bridged
by surfactants, called chemically dispersed oil (CDO), can
dwell in seawater for a longer period of time with the
proper conditions (Tsutsumi et al. 2000). Identifying
CDO is desired for environmental assessment, selecting
appropriate follow-up response countermeasures, and to
better understand the fate and behaviors of CDO (Wang
and Fingas 2003).
Oil fingerprinting is one of the key technologies to identify
and differentiate the sources of unknown oil and associated
refined products spilled into the environments (Bayona et al.
2015). The categories of spilled oil are evaluated by the diag-
nostic relationships among specific hydrocarbons, known as
biomarkers (Hostettler et al. 2007). Biomarkers in certain oils
can be uniquely distributed to pinpoint the specific geographic
source, oil processing method, and weathering status (Wang
et al. 2006a). The most commonly and widely identified bio-
markers applied in oil spill environmental forensics are ali-
phatic and aromatic hydrocarbons. Aliphatic biomarkers
mainly include diamondoids, sesquiterpanes, steranes, and
terpanes. Diamondoids are known as three-dimensional cyclo-
hexane-ring alkanes naturally existed in petroleum (Gao et al.
2016). Diamondoids, especially adamantanes and
diamantanes, are also used as a tool to evaluate the maturity
of crude oil and to differentiate oil types due to their differen-
tiable distributions. But, diamondoids are not widely applied
in case studies in comparison with terpanes and steranes
(Chen et al. 1996; Springer et al. 2010;Wangetal.2006b).
Sesquiterpanes are cyclic saturates commonly discovered in
different types of oils. Diverse oils with different weathering
degrees, such as light oil, diesel, and heavy fuel (Wang et al.
2005), can be differentiated by the diagnostic ratios of
Responsible editor: Roland Peter Kallenborn
Electronic supplementary material The online version of this article
(https://doi.org/10.1007/s11356-018-1730-y) contains supplementary
material, which is available to authorized users.
* Baiyu Zhang
Faculty of Engineering and Applied Science, Memorial University of
Newfoundland, St. John’s, NL A1B 3X5, Canada
Environmental Science and Pollution Research (2018) 25:15702–15714