United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
Research Triangle Park NC 27711
Research and Development
EPA/600/S4-86/029 Sept. 1986
&EPA Project Summary
Stability of Polynuclear
Aromatic Compounds
Collected from Air on Quartz
Fiber Filters and XAD-2 Resin
J. C. Chuang, S. W. Hannan, and J. R. Koetz
The objective of this project was to
investigate the stability of polynuclear
aromatic hydrocarbons (PAH) collected
from ambient air on quartz fiber fitters
and XAD-2 resin.
Eight EPA medium volume samplers
were set up to collect ambient air for
24 hours at a 6.7 dm flow rate. Quartz
fiber filters and XAD-2 resin were used
to collect particulate-bound and vapor-
phase PAH. Prior to sampling, selected
perdeuterated PAH in solution were
spiked onto the XAD-2 resin. After col-
lection, two of the filter and XAD-2
resin samples were extractd immedi-
ately, and the remaining filters and
XAD-2 resin were extracted after 10,20,
and 30 day intervals. The storage tem-
perature was approximately 70°F, and
the samples were kept in the dark.
Sample extracts were analyzed by elec-
tron impact gas chromatography/mass
spectrometry (El GC/MS).
The results indicated that the levels
of perdeuterated and native PAHs on
the XAD-2 resin were not adversely in-
fluenced by the storage time. The levels
of most native PAH, except for cy-
clopenta[c,d]pyrene, adsorbed on the
quartz fiber filters were also not influ-
enced by the storage time. The levels of
cyclopenta[c,d]pyrene found in the fil-
ters decreased from 1.28 ng/m3 to 0.79
ng/m3 after storage for 30 days.
This Project Summary was devel-
oped by EPA's Environmental Monitor-
ing Systems Laboratory, Research Tri-
angle Park, NC, to announce key
findings of the research project that is
fully documented in a separate report
of the same title (see Project Report
ordering information at back).
Introduction
Polynuclear aromatic hydrocarbons
(PAH) have been extensively studied
and have received increased attention
in studies of air pollution in recent years
because some of these compounds are
highly carcinogenic or mutagenic. To
understand the extent of human expo-
sure to PAH, reliable sampling and
analytical methodology must be estab-
lished for monitoring the concentra-
tions of these compounds in air. In gen-
eral, the analytical methodology is well
developed, but the sampling proce-
dures can often reduce the validity of
analytical results. Several studies have
shown that the two- to four-ring PAH in
air may be mainly in the vapor phase
and are not retained by filters because
of volatilization. Quartz fiber and glass
fiber filters are typically used in sam-
pling air particles. A wide variety of ad-
sorbents such as XAD-2 resin and
polyurethane foam (PUF) has been used
to sample PAH vapors. However, the
overall comparative effectiveness of the
collection media and the degree to
which quantification of the PAH is af-
fected by sampling, handling and stor-
age are not fully investigated. Recently,
Battelle conducted a study to evaluate
the stability of PAH collected on
polyurethane foam (PUF) as a function
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of storage conditions. As a follow-up
study, the stability of PAH samples col-
lected on quartz fiber filters and XAD-2
resin were evaluated in this program.
The objective of this project was to
evaluate quartz fiber filters and XAD-2
resin for collection of particle-bound
and vapor-phase PAH in air.
Procedure
The stability study was performed to
determine the stability of PAH adsorbed
on quartz fiber filters and XAD-2 resin
by examining the measured PAH con-
centrations as a function of storage time
between collection and extraction. The
sample extracts were analyzed by elec-
tron impact gas chromatography/mass
spectrometry (El GC/MS) to determine
both native and spiked perdeuterated
PAH.
Results
The stability study was conducted to
determine whether a significant loss of
PAH captured by XAD-2 resin and
quartz fiber filters occurred during the
storage period. The samples were
stored at room temperature (~70°F) in
the dark for 0, 10, 20, and 30 days. Re-
coveries of the perdeuterated PAH for
XAD-2 samples ranged from 71 percent
for D12-benzo[a]pyrene to 103 percent
for D8-naphthalene. Generally, good re-
coveries were obtained for all the spiked
PAH. The storage time did not appear to
have adverse effects on the recoveries
of the spiked PAH.
The distribution of native PAH be-
tween the filters and XAD-2 resin
agreed with the volatilities of the com-
pounds, and the majority of the volatile
PAH (<4 rings) were captured on the
XAD-2 resin. The non-volatile PAH, such
as BaP and coronene, were captured
mainly on the quartz fiber filters. The
storage time did not significantly affect
the levels of the PAH adsorbed on the
XAD-2 resin. In addition, the storage
time did not appear to have adverse ef-
fects on the levels of most PAH captured
on the quartz fiber filters, except for cy-
clopenta[c,d]pyrene. The levels of cy-
clopenta[c,d]pyrene decreased from
1.28 ng/m3 (34.8 ng/mg of particles) to
0.79 ng/m3 (17.8 ng/mg of particles)
after 30 days storage.
Conclusions and
Recommendations
Generally, good recoveries for the
spiked perdeuterated PAH were ob-
tained for all XAD-2 samples. The recov-
eries of perdeuterated PAH did not de-
crease after storage for 30 days.
However, results of a previous study
showed that lower recoveries (1.2 to
0.6 percent) were obtained for D8-
naphthalene from spiked PDF. The re-
coveries of D12-BaP were also de-
creased from 96 to 30 percent after
30 days storage. This finding demon-
strated that XAD-2 resin has better re-
tention efficiency for the volatile and re-
active PAH than the PUF cartridge does.
The stabilities of native PAH adsorbed
on XAD-2 resin and quartz fiber filters
were investigated. The results showed
that only cyclopenta[c,d]pyrene levels
decreased significantly during storage.
The loss of cyclopenta[c,d]pyrene was
probably due to chemical reaction, be-
cause the five member ring is highly
susceptible to oxidation. Therefore, if
quartz fiber is used for air sampling,
minimum sample handling and storage
time is recommended to minimize the
loss of some active PAH.
In this study, quartz fiber filters were
used to collect air paniculate matter.
However, there are other types of filters
that can be considered for collecting
particles. Very few studies have been
conducted to evaluate filter material for
collection of particle-bound PAH. One
research group has evaluated various
candidate filter materials including
glass fiber, quartz fiber, microglass fiber
with Teflon binder, and Teflon mem-
brane filters. Experiments were per-
formed by spiking solutions of BaP onto
filters to determine the recoveries. Spik-
ing of BaP, however, does not represent
the native adsorption process of BaP in
ambient air sampling. Therefore, we
recommend that a study be conducted
to compare different types of filters
such as quartz fiber, glass fiber, and
Teflon-coated filters for collection of
PAH from air. Several important charac-
teristics such as flow rate and collection
efficiency should be addressed. In addi-
tion, studies to determine the effects of
storage time on PAH samples collected
on different types of filters, such as
glass fiber and Teflon-coated filters, are
also recommended.
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J. C. Chuang. S. W. Hannan, andJ. R. Koetzare withBattelle Columbus Division.
Columbus, OH 43201 -2693.
Nancy K. Wilson is the EPA Project Officer (see below).
The complete report, entitled "Stability of Polynuclear Aromatic Compounds
Collected from Air on Quartz Fiber Filters andXAD-2 Resin," (Order No. PB
86-223 054/AS; Cost: $9.95, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring Systems Laboratory
U.S. Environmental Protection Agency
Research Triangle Park. NC 27711
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S4-86/029
0000329 PS
'GEI*ey
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