Environmental Engineering Reference
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Biomass combustion occurs at relatively low temperatures and is a significant
source of pyrogenic PAHs in nearshore subtidal sediments (Barra et al. 2007 ; Gogou
et al. 2000 ; Oanh et al. 1999 ; Page et al. 1999 ; Tobiszewski and Namiesnik 2012 ).
However, aerosol from wheat and rice straw burning is enriched in HMW PAHs
(Ravindra et al. 2008 and references therein). Stark et al. ( 2003 ) identified three- to
six-ringed parent PAH compounds as the major PAHs in fireplace soots (see also
Figs. S18-S20, Supporting Material); alkylated three- and four-ringed compounds
were less abundant. Stark et al. ( 2003 ) noted that when soots have high total PAH
concentrations, they also contain larger amounts of three- and four-ringed parent
compounds. In contrast, soots with lower total PAH concentrations show a relative
increase in the amounts of five- and six-ringed PAHs.
Guillon et al. ( 2013 ) identified fluoranthene and pyrene as dominant parent PAH
compounds in particulates from wood combustion, whereas the dominant parent
HMW PAHs are benz[ a ]anthracene and chrysene, followed by benzo[ a ]pyrene.
Cyclopenta[ a ]phenanthrene, phenylnaphthalene and either cyclopenta[ cd ]pyrene or
benzo[ ghi ]luoranthene are present in fireplace soots (O'Malley et al. 1997 ; Stark
et al. 2003 ). Other HMW PAHs such as benzo[ ghi ]perylene are also produced by
biomass combustion (Dzepina et al. 2007 ).
Under certain conditions (e.g., steady combustion and forest fires), and in con-
trast to HMW parent PAHs, alkylated naphthalenes, phenanthrenes, and even chry-
senes may be ubiquitous biomass combustion products (Figs. S18-S20, Supporting
Material; Wang and Fingas 2003 ). Furthermore, three-ringed alkyl PAHs such as
1-methylphenanthrene, 1,7-dimethylphenanthrene (also known as pimanthrene)
and retene (1-methyl-7-isopropyl phenanthrene) are produced from abietic and
pimaric acid—both present in pine wood resin—and can be used as markers for
softwood combustion (Benner et al. 1995 ; Bucheli et al. 2004 ; Gogou et al. 2000
Sicre et al. 1987 ; Yan et al. 2005 ; Yunker et al. 2002 ). The 2,6- dimethylphenanthrene
isomer is present at comparable concentrations in emissions from fossil fuel and
residential wood combustion (Benner et al. 1995 ).
The PAHs derived from coal combustion are a concern in some regions of the
world (Chen et al. 2005 ). Fluoranthene, pyrene, phenanthrene and anthracene domi-
nate in coal combustion profiles (Larsen and Baker 2003 and references therein).
Chrysene and benzo[ k ]luoranthene dominance has also been suggested as an indi-
cator of coal combustion (Ravindra et al. 2008 and references therein).
Dibenzothiophenes are also abundant in coal emission condensates (Marvin et al.
2000 ; Sicre et al. 1987 ) and industrial coal emissions, and escape from most modern
SO x removal processes (Lehndorff and Schwark 2009 ).
Coal combustion patterns sometimes deviate from the general pyrogenic finger-
print of PAH homologues (i.e., maxima at the parent PAH), and can show maxima
for the methyl or dimethyl homologues of phenanthrene and anthracene (Oros and
Simoneit 2000 ; Yunker et al. 2002 ). Similarly, four-ringed methyl PAHs methylflu-
oranthene or methylpyrene may also show maxima in coal combustion PAH patterns
(Oros and Simoneit 2000 ; Yunker et al. 2002 ). PAH emissions from coal burning
depend not only on the coal rank, but also on the temperature of combustion.
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