J2LCRA Office of Superfund Remediation and Technology Innovation
X/Crrt and
United States
Environmental Protection r*rf r n , \ rx ,
Agency Office of Research and Development
Sediment Assessment and Monitoring Sheet (SAMS) # 3
Guidelines for Using Passive Samplers
to Monitor Organic Contaminants
at Superfund Sediment Sites
December 2012
OSWER Directive 9200.1-110 FS
-------
Contents
1. Introduction 1
2. Why use passive samplers? The advantages 2
3. What passive samplers tell us 5
4. Types of passive samplers 7
5. Some theory on how passive samplers work 9
6. Preparing, deploying, recovering, and storing passive samplers 11
7. Selecting passive samplers 15
8. Analyzing passive sampler data 15
9. Briefcase study 19
10. Remaining scientific challenges in using passive samplers 20
11. US EPA contacts working with passive samplers 22
12. Summary 22
13. Acknowledgements 24
14. References used in this document 25
Appendix A 29
Mention of trade names or commercial products in this document does not constitute the U.S.
Environmental Protection Agency's endorsement or recommendation for use.
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
1. Introduction
The objective of this Sediment Assessment and Monitoring Sheet (SAMS) is to provide introductory
information on the use of passive samplers at Superfund sediment sites contaminated with hydrophobic
organic contaminants. The concept of passive sampling in the environment was first developed in the
1980s, and samplers started to be deployed in the field for research purposes in the 1990s. Since
then, passive samplers have been used for monitoring contaminant concentrations in the water column,
soil and sediment interstitial waters, and air at sites around the world. Their use in sediments to date
has been primarily for research, however. As discussed below, passive samplers are useful new tools
for assessing contaminant exposures and evaluating the potential for adverse environmental effects at
Superfund sites. After reading this SAMS, users will have a fundamental understanding of some
common passive samplers and their potential applications at Superfund sites.
This SAMS discusses passive samplers that can be used in both water column and sediment
deployments, and in some cases both simultaneously. These passive samplers use polyethylene (PE),
polyoxymethylene (POM), and solid phase micro-extraction (SPME) materials. Another type of passive
sampler called semi-permeable membrane devices (SPMDs) have been used primarily in the water
column as surrogates for biota such as fish, but will not be discussed here in any depth. When
deployed together, passive samplers placed in the water column and in the sediment can provide
information about contaminant gradients between the sediment and the water. For example, when an
engineered cap is used as part of a site cleanup, passive samplers can be used as a monitoring tool to
evaluate the contaminant flux from the underlying contaminated sediment, into the cap layers and into
the overlying water. Passive samplers collect information about the dissolved concentrations of
contaminants. The dissolved concentration is a useful measure of the amount of contaminant that is
bioavailable to aquatic organisms. Passive samplers do not provide information about the
concentrations of contaminants associated with bedded, suspended or colloidal particles in aquatic
systems and therefore do not address directly the transport of contaminants associated with such
particles. The focus of this document is on a subset of those contaminants of concern (COC) often
found at Superfund sites that, chemically speaking, are known as the hydrophobic or nonionic organic
chemicals. These include polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs),
polychlorinated dioxins and furans (PCDD/Fs) and chlorinated pesticides such as DDT. These
chemicals are particularly persistent in the environment and bioaccumulate in aquatic organisms, often
drive the risks as Superfund sediment sites, and are the focus of this SAMS. Metal COC such as
cadmium, copper, lead, mercury and zinc are not discussed. There is a growing scientific literature on
using other types of passive samplers to monitor metals, but the field is not as established, and that
work is beyond the scope of this SAMS. This document briefly discusses the use of passive samplers
but does not provide specific protocols on deployment and recovery, nor does it describe the chemical
analysis procedures for passive samplers (it is not a U.S. Environmental Protection Agency [EPA]
standard method or operating procedure). However, with the increasing use of passive samplers at
sites around the United States and the world, these types of specialized protocols and procedures are
likely to be available in the near future.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
1
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
2. Why Use Passive Samplers? The Advantages
At Superfund sites, there often is the need to know the concentrations of hydrophobic organic
contaminants in the water column and sediment interstitial water, and to understand the relationship
between these levels and the total levels in the sediment (i.e., bulk sediment chemistry). Depending on
the contaminant, there may be several ways to
measure these concentrations. The typical
analytical methods are gas chromatography
with mass spectroscopy (GC/MS) or electron
capture detection (GC/ECD) for most of the
contaminants considered in this SAMS. These
methods measure the quantity of these
contaminants in a selected matrix like water or
sediment. However, before the analysis can be
performed, it is necessary to collect the sample
matrix and extract the contaminants from that
matrix. For the last 40 years, these hydrophobic
contaminants have been extracted from a
volume of water or mass of sediment using
organic solvents. This conventional approach
has several disadvantages. First, for water
samples, even at the most contaminated sites,
contaminant concentrations are frequently so
low that they are not detectable with the GC/MS
or GC/ECD unless very large volumes of water
(e.g., tens to thousands of liters) are extracted.
Furthermore, even when contaminants can be
detected, the results are often affected by
sample artifacts like the presence of very small
sediment particles, colloids and dissolved
organic carbon (DOC), and thus the measured
concentrations do not represent the truly
dissolved and bioavailable concentrations.
These additional environmental phases (defined
in Table 1 and discussed in Information Box #1)
can result in overestimations of the dissolved
concentrations in the water column and
interstitial water. Second, for sediments,
solvent extraction removes nearly all of the
contaminants from the sediment, including that
portion tightly bound or sequestered in the
sediment matrix. While this type of information
is useful for quantifying the total mass of
Information Box 1 Environmental phases are often
used to divide the aquatic environment into separate
components, each with its own unique characteristics.
Understanding environmental phases and where a
contaminant resides in these phases can assist in
establishing whether the contaminants will be in a
form resulting in exposure to aquatic organisms,
wildlife and humans. Principal environmental phases
important to contaminated sediment sites are defined
in Table 1. Definitions are generally based on the
particle size or chemical qualities (e.g., sorption
strength of carbon types) of the substances making-up
the phase. Hydrophobic organic chemicals partition
between these environmental phases. In general, the
majority of these contaminants will be associated with
the particulate phase and are not typically readily
bioavailable to result in an exposure. A portion of
these contaminants will also associate with the
colloidal and dissolved organic carbon (DOC) phases,
where they are also not readily bioavailable. Often the
least amount of contaminants will be in the truly
dissolved phase, but this is the phase where they are
the most readily bioavailable for exposure and uptake
by organisms.
Dissolved
Organic 4
Carbon
Particulate
Contaminant
of
Concern
Colloids
Truly
Dissolved
The image above shows the partitioning of a
hydrophobic COC between the principal
environmental phases, with the thickness of the
arrows indicating the relative degree to which a
contaminant associates with a given phase (based on
Schwarzenbach and others (2003)).
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
contaminant present in the sediments, it does not tell us anything about what fraction of the
contaminants are bioaccessible or bioavailable to environmental receptors and thus responsible for
exposure and potential risks to human health and environment (see Information Box #2). In addition,
conventional extractions use large volumes of organic solvents that are both expensive and
environmentally harmful. By comparison, passive samplers require much smaller volumes of solvent.
Table 1. Definitions of principal environmental phases in the aquatic environment.
Environmental Phases in
Water
Black carbon (BC)
Definition
A form of carbon produced by the burning of biomass and fossil fuels that
can accumulate in sediments. This form of carbon has a very large affinity
for hydrophobic COC and can substantially reduce bioaccessibility and
bioavailability. Depending on the type of sediment, the BC generally
constitutes 0.05 to 1.0 percent of the sediment mass.
Colloidal
Very small particles that do not settle as a result of gravity (larger than 10
nanometer [nm] to less than 10 micrometer [urn]) when present in the
water column and in sediment interstitial water. When associated with
colloids, COC bioavailability is substantially reduced.
Dissolved
Contaminants existing in a dissolved form in the water column and
interstitial waters, a highly bioavailable form of most organic COC.
Dissolved organic carbon
(DOC)
Organic matter, smaller in size than colloids, that is chemically dissolved in
water. As in the case with colloids, when associated with dissolved
organic carbon, the bioavailability of COC is substantially reduced.
Interstitial or pore water
In the sediment bed, water present between particulates; it contains
colloidal, dissolved organic carbon and the truly dissolved phase of COC.
Particulate
Large sediment particles (larger than 10 urn) containing organic and black
forms of carbon that settle fairly quickly via gravity when resuspended.
Particulate organic carbon
(POC) or sedimentary organic
carbon (SOC)
Organic carbon associated with sediment particles and formed by the
natural degradation of biomass (such as plants and animals). Depending
on the type of sediment, the POC can constitute 0.5 to 10 percent of the
sediment mass. Many COC are sequestered by POC, which reduces their
bioaccessibility and bioavailability. The affinity of this form of carbon for
COC is substantially less than their affinity to black carbon. When
analyzed by scientific instrumentation, POC is also known as total organic
carbon (TOC) and the fraction organic carbon (f0c)-
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Passive samplers represent an alternative
approach for collecting and extracting some key
organic COC and have many advantages over
the conventional approaches. For example,
passive samplers can be deployed directly in the
environment and concentrate COC in situ. This
concentrating process increases the sensitivity of
the GC/MS or GC/ECD used to analyze the
sampler because there is more contaminant
present in the final extract. Other advantages are
that passive samplers can be deployed for
several days at a time (up to several months) and
provide a time-averaged representation of COC
concentrations at the sampling stations. In
contrast, conventional water samples provide a
"snap shot" of conditions at one, often brief,
moment in time that may not be representative of
average or real concentrations to which receptors
are exposed. Finally, while the actual cost of a
chemical analysis by GC/MS or GC/ECD for a
passive sampler is similar to a conventional
sample, passive samplers themselves can be
inexpensive. Therefore, the cost of the passive
sampler deployment generally is $100 to $200
less than conventional sampling, and the loss of a
passive sampler during a deployment as a result
of bad weather or boat traffic is not a large
financial loss.
Information Box 2 Bioaccessibility and
bioavailability are terms that describe the likelihood
that a contaminant will be exposed to an organism.
Actual definitions vary, but a general definition of
bioaccessibility is the amount of a chemical that is
in a form that an organism can access from an
environmental phase. If that contaminant is able
to interact within an organism (for example, it can
be accumulated by a fish's lipids), the contaminant
is considered bioavailable. As noted in Information
Box 1, contaminants may be associated with
several environmental phases in water and not all
are equally bioaccessible or bioavailable. For
example, contaminants associated with the black
carbon in a sediment are considered almost
completely non-bioaccessible and therefore not
likely to be bioavailable. In contrast, contaminants
truly dissolved in the water are considered very
bioaccessible and therefore likely to be
bioavailable and taken up by an organism. It is
critical to note that contaminants truly dissolved in
the water are not the only bioavailable
contaminants in an environmental system. Other
phases can contribute bioavailable contaminants;
however, the dissolved water concentration is
often a good surrogate for the bioavailable
concentration in a given environmental system.
Passive samplers collect contaminants only from
the bioaccessible form and thus are good
estimators of what is bioavailable. See
Reichenberg and Mayer (2006) for more
discussion.
As an example of comparative expenses, Table 2
presents the costs of analyzing several types of
samples for the 20 PCB congeners measured by the National Oceanic and Atmospheric Administration
(NOAA) as part of its National Status and Trends Program. Built into these estimates is the assumption
that 10 to 20 water samples are being extracted by conventional methods or passively sampled then
analyzed by GC/MS.
Table 2 shows that total costs for the analysis of the PE, POM and SPME passive samplers range from
$310 to $425, with most of the cost associated with the chemical analysis; materials costs range from
only $5 to $50. It is worth noting again that once a conventional sample has been reduced to the
chemical extract and injected into the GC/MS or GC/ECD for analysis, the costs are identical
regardless of the type of sampler. The overall costs vary depending on material expenses and any
preparation related to the sample. The labor associated with extracting contaminants from 5 liters of
water also adds costs compared with extracting a few grams of sampler, or milligrams of sampler, in
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
the case of the SPME. Finally, the analysis of the PE, POM and SPME samplers is still relatively new to
many commercial analytical laboratories. The cost of analysis is likely to decrease as these types of
samplers continue to be used more often and the procedures become more familiar.
Table 2. Comparison of costs for analyzing different types of samples for 20 National Oceanic
and Atmospheric Administration (NOAA) PCBs.
Type of Sample
Water
(5 L by conventional method)
Polyethylene (PE)
Polyoxymethylene (POM)
Materials
(samplers &
deployment
equipment) ($)
<5
~5
-50
Chemical
Analysis ($)
525
375
375
Total ($)
530
380
425
-35
275
310
Solid Phase Micro-extraction
(SPME)
Note: Costs provided courtesy of an independent laboratory. Cost values in dollars are reported per sample.
3. What Passive Samplers Tell Us
Passive samplers can provide a more scientifically sound and cost effective way to measure or predict
the concentration of hydrophobic contaminants in the dissolved phase. Furthermore, data from passive
samplers can result in more accurate as well as more biologically relevant measurements than
conventional sampling methods. For example, current sampling methods typically define the dissolved
phase as the amount of a contaminant that passes through a 0.4-micron (urn) filter. This operational
definition, however, does not have a real biological basis.
Figure 1 is a conceptual diagram showing how actual water column concentrations of a COC at a site
might vary over time (shown as a blue line). We do not currently have the technology to accurately
measure the actual dissolved concentration represented in Figure 1 in a fashion that is free of artifacts.
Conventional methods, which involve collecting a sample of water at one point in time only provide a
"snap shot" of the COC concentration. However, such a measurement can be valuable, especially
when information is needed quickly or a chemical is acutely toxic but it can also be biased by the
artifacts discussed above (e.g., presence of DOC and colloids). Furthermore, these measurements can
be affected by short-term temporal events (such as storms) that either result in an elevated or a
reduced dissolved concentration that does not accurately reflect long-term average concentrations at
the site.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Knowing the long-term average concentrations is critical when we want to understand what local
organisms are being exposed to over longer time periods. Because passive samplers monitor water
column or interstitial water concentrations over time, they provide a more representative "time-
integrated" measurement that better reflects the average exposures experienced by local organisms.
In Figure 1, the red line reflects the passive sampler-based water column concentration of a COC
showing the time-integrated measurement of dissolved concentrations.
CUD
c
o
.p
O
to
to
Storm Event
Actual Concentration
Passive Sampler-based Concentration
Time (days)
oo
Figure 1. Conceptual diagram of the dissolved water column concentration of a hydrophobic
contaminant shown as the actual concentration (blue line) and the passive sampler-based
concentration (red line).
Passive samplers provide two basic types of information:
(1) Concentration of COC in the passive sampler. This type of information is obtained by analyzing
the solvent extract collected from the sampler. This information is useful because there is growing
evidence that a good correlation exists between the concentration of COC accumulated by passive
samplers and the concentration bioaccumulated by aquatic organisms, especially those closely
associated with sediment (e.g., benthic invertebrates). For example, in a limited number of studies,
bioaccumulation by organisms used in biomonitoring and sediment assessments, like benthic worms,
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
showed good agreement with the concentration accumulated by passive samplers (i.e., a linear
relationship) (Vinturella and others 2004, Friedman and others 2009, Gschwend and others 2011).
This agreement suggests that, under appropriate conditions, passive samplers could be used as
surrogates for these animals.
(2) Concentration of COC dissolved in the aqueous phase around the passive sampler. The
dissolved concentration of COC in the water column or interstitial waters is the most bioavailable
concentration and therefore the quantity needed to better understand the true exposure conditions at
the site. This concentration is calculated based on the concentration of COC in the sampler (data from
[1] above) and a simple mathematic relationship discussed in Section 8. In practice, this concentration
can be compared with water quality standards or criteria, risk-based values, or background levels to
assess the impact of potentially high concentrations in the water column and sediment interstitial
waters.
4. Types of Passive Samplers
This SAMS discusses the three most commonly used types of passive samplers. These are:
Polyethylene (PE)
Polyoxymethylene (POM)
Solid Phase Micro-extraction (SPME)
Passive samplers are essentially pieces of plastic, or more specifically, organic polymer. Their
composition is discussed in more detail in the next section. As pieces of plastic, they are fairly simple
objects. Figure 2 provides photographs of the three passive samplers. As shown in Figure 2, the PE
and POM passive samplers are simply pieces of plastic sheeting that range from about 15 urn to 100
urn in thickness and can be easily cut with scissors to be as large or small as needed. The PE plastic
drop cloth available from hardware stores is frequently used as passive sampler material. The POM
passive sampler uses a more specialized type of polymer, but it also can be purchased in large sheets.
The SPME passive sampler is, as Figure 3 illustrates, actually fiber-optic cable. The inner fiber core
consists of glass that does not readily absorb hydrophobic contaminants but the insulating polymer,
polydimethylsiloxane (PDMS), coating the glass core is an absorptive material effective for passive
sampling. The PDMS coating can be purchased in a variety of thicknesses from about 10 to 100 urn.
The coated fibers can be various lengths but can be fragile, so shorter lengths of 1 to 20 centimeters
are commonly used; however, lengths up to one meter have been deployed in the environment.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
fiber-optic cable
Figure 3. Close-up view of SPME fiber.
As noted earlier, a fourth sampler called a SPMD was one of
the first environmental passive samplers developed and it has
been applied extensively in water column deployments for
decades (Huckins and others 1993, 2006). However, SPMDs
have not been used very frequently in sediments although they
have been applied to examine sediment-water interface
processes (Schubauer-Berigan and others 2012). Because of
their infrequent use in sediments, SPMDs will not be discussed
any further in this SAMS.
Figure 2. Photographs of
selected passive samplers.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
8
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
5. Some Theory on How Passive Samplers Work
As noted earlier, commonly found COC, like PCBs,
DDTs, and high molecular weight PAHs are
hydrophobic. That is, they have little affinity for
water. Passive sampling takes advantage of the
hydrophobicity of COC to collect and concentrate
these contaminants by deploying material in the
system being assessed or monitored that is also
hydrophobic. Hydrophobic contaminants follow the
old organic chemistry adage "like dissolves like";
that is, if a hydrophobic material is placed into water
under the right conditions, hydrophobic
contaminants will dissolve into the other
environmental phases, including a passive
sampler, rather than remain dissolved in the water.
H
1 H
(a) C-.. i .
i ' C '
H 1
H
H
(b) C-.
i ''-.O
H
H
1
H-C -H
(C) Si
H-C-H ""°"'
1
H
H H
1 H 1 H
C-. " .-C-. 1
i 'c--' i "--c
H 1 H 1
H H
H H H
1 1 1
..c.. .. c-. ..c-.
' i 'o--'' i 'o--'' i
H H H
H H
1 1
H-C -H H-C -H
1 1
...Si... ..-Si...
1 (V'""°* '
H-C-H H-C-H
1 1
H H
&&&**&
H
1
.C
o--' i
H
r\vif
Information Box 3 Equilibrium is a
physicochemical term that describes, for this
SAMS, the apparent lack of transfer of
contaminants from one environmental phase to
another. Specifically, equilibrium is established
when the change in the amount of COC
transferring from one phase to another, on
average, is equivalent to zero. Though it can be
an abstract concept, equilibrium simply indicates
that we do not expect any significant change over
time in the concentration of a COC in any phase
we may want to measure. By knowing the system
is at equilibrium and the concentration of COC is
no longer changing in any phase, we can be
confident that any inferences we make about
concentrations within the system will be accurate
and will not change significantly. A clear way to
visualize equilibrium for COC concentrations is to
plot concentration versus time. Once the
concentration in the sampler is no longer
changing with time, we can conclude that
equilibrium has been achieved. See
Schwarzenbach and others (2003) for more
discussion.
Figure 4. Basic polymer structure of
(a) polyethylene, (b) polyoxymethylene and
(c) polydimethylsiloxane. C is carbon, H is
hydrogen, O is oxygen and Si is silicon. Three
dimensional views of polyethylene and
polydimethylsiloxane are also shown (from
Wikipedia).
In passive sampling, the hydrophobic material is an
organic polymer that is fundamentally similar in
hydrophobicity to many hydrophobic contaminants.
Figure 4 illustrates the molecular structure of these
polymers. In the actual polymer, these structures
would be repeated millions of times to form large,
layered sheets of material. As shown in Figure 5,
when a sheet of this material is placed in water with
contaminants, such as PCBs, present in the
dissolved phase, the PCBs will partition into the
polymer, moving out the water and dissolving into
the polymer (Figure 5a). Over time, the PCBs will
accumulate in the sampler (Figure 5b) until the
change in the PCB concentration in the passive
sampler no longer is increasing (Figure 5c). Note
that if concentrations of PCBs decline in the water,
PCB concentrations in the passive sampler may also
decrease. Once these changes in PCB
concentrations in the passive sampler are no longer
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
significant, the PCBs are considered to be at equilibrium between the passive sampler and the various
environmental phases, most importantly the dissolved phase in the water (see Information Box #3).
Once a sampler has achieved equilibrium, it can be retrieved, and analyzed for COC to acquire the
information samplers provide, as discussed in Section 3.
_
o.
CO
CO
Q)
03
Q_
c
g
to
I
o
O
CD
O
Q.
0
Time
CO
Figure 5. Conceptual schematic of PCB ( P ) uptake by a passive sampler
from (a) initial deployment, (b) through uptake, and (c) achieving equilibrium. The
number of PCB molecules is not intended to be quantitative but rather demonstrate
relative changes in the concentrations of PCBs over the deployment period.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
10
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
6. Preparing, Deploying, Recovering, and Storing Passive
Samplers
This section provides an overview of the steps involved in preparing, deploying, recovering, and storing
recovered passive samplers. As previously noted, more specific guidance is being developed by others
and should be available soon. Before deployment, it is critical to ensure samplers are not contaminated
with any COC. As shown in Figure 5a, the assumption is that the samplers are free of any
contamination at the time of deployment. Generally, preparation of the samplers involves soaking them
in organic solvent for several hours to days before deployment, followed by soaking or rinsing with
clean water. After they have been cleaned, it is also critical to reduce the potential for recontamination
from laboratory, air, car or truck, boat and dock surfaces, or other sources. After the cleaning and
rinsing, the samplers are often wrapped in aluminum foil, placed inside a plastic bag, and frozen (-4°C)
until they are ready for deployment. Different types of samplers require different kinds of deployments.
PE and POM can be deployed in the water column on stainless steel wire loops that maximizes the
sampler surface area exposed to the water (and dissolved contaminants) (Figure 6a). They can also
be deployed in enclosures like fish traps to reduce the potential for sampler loss and protect them from
being torn by currents, severe weather, or boat traffic, or eaten by aquatic organisms (Figure 6b). In
general, stainless steel wire can be used to attach the passive samplers to anchor lines and to the
inside of fish traps during deployments. These types of passive samplers are often deployed in 0.5 to
1.0 meter-long strips that are about 10 to 15 centimeters wide.
SPME samplers can be fragile, especially those fibers with a very thin coat of PDMS (such as 10 urn)
and need to be deployed in some form of protective container. These containers can include stainless
steel or copper mesh envelopes or tubing (see Figure 7). Often, several SPME fibers 2 to 20
centimeters long will be placed inside the mesh to increase the amount of polymer, which enhances the
sensitivity of later chemical analysis. However, pieces of SPME fiber up to a meter long have been
deployed in stainless steel tubes (Figure 7d). Sediment deployments require less polymer because
COC concentrations in sediment are usually much higher than are observed in the water column.
Therefore, the concentrations that accumulate in the sampler reach levels that are analytically
detectable with less need for large amounts of polymer. For instance, a piece of PE or POM one to
three centimeters square can easily be inserted into sediment without any special protection or
equipment (Figure 7a). For example, using a large pair of forceps, PE was inserted into sediments
during a standard bioaccumulation study (Friedman and others 2009). For field deployments, PE and
POM have been placed in sediments in situ with metal frames that maintain the surface area of the
polymer (Figure 7b) (Fernandez and others 2009). Furthermore, when passive samplers are in these
metal frames, interstitial water and surface water concentrations can be measured simultaneously to
assess the gradient of contaminants between the sediment bed and the water column. To avoid
damaging the PDMS-coated fibers, copper tubing and other types of tubing and casings (such as
stainless steel and copper mesh) have been used to deploy SPME in sediments (Figure 7c) (Maruya
and others 2009, D. Reible, personal communication). Other variations on these types of in situ
deployments in sediments of passive samplers are described by Booij and others (2003), Tomaszewski
and Luthy (2008), Janssen and others (2011), Oen and others (2011) and Burton and others (2012).
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
11
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Passive samplers can easily be deployed in the field with limited costs using inexpensive equipment.
Figure 8 illustrates a number of deployment strategies for passive samplers in the water column and
sediment at a contaminated site. As noted above, passive samplers can be deployed in the water
column using fish traps (Figure 8a), stainless steel wire loops (Figure 8b), and copper tubes (Figure
8c). Figure 8d shows passive samplers deployed in sediments using metal frames with PE or POM
polymers and a copper tube and stainless steel rod containing SPME fibers. In some waterbody
locations it may be better not to use buoys at the surface, but below the surface to prevent tampering
and disruption by wave action. The Office of Superfund Remediation and Technology Innovation
(OSRTI) Environmental Response Team's Dive Team as well as Region 10's Dive Team have
extensive experience deploying and retrieving passive samplers in sediments and can be a valuable,
cost-effective resource to use when considering the application of passive samplers at sediment sites.
More information on the dive teams can be found at:
www.ert.org/mainContent.asp?section=Dive&subsection=About and
vosemite.epa.gov/R10/OEA.NSF/investigations/dive+team+videos.
After the deployment period (often 28 days), the samplers are recovered and wiped clean with
laboratory tissues to remove site water and sediments and any biological growth. If the samplers still
retain a film of residual sediment or biological growth, they should be rinsed with clean water for about
a minute or wiped with a damp laboratory tissue to remove as much remaining material as possible
without damaging the samplers. Once samplers are cleaned, they are wrapped in clean aluminum foil,
stored in an ice-filled or artificial ice-filled cooler, and returned to the laboratory as soon as possible,
and then stored at -4°C until chemical analyses are initiated.
Passive samplers can also be used in ex-situ conditions. In this approach, contaminated sediment is
collected in the field and returned to the laboratory. Passive samplers are then added to the sediment
during laboratory bioaccumulation and partitioning studies (Mayer and others 2000, Booij and others
2003, Vinturella and others 2004, Friedman and others 2009, Gschwend and others 2011, Hawthorne
and others 2005, 2009, Lampert and others 2011, Lu and others 2011) to measure the COC
concentrations. This ex-situ strategy has the advantage of being able to control, under laboratory
conditions, many of the environmental variables, such as temperature, that are uncontrollable in the
field. This type of deployment is also often less expensive than in situ deployments. However, the ex
situ approach departs from the natural conditions that reflect reality at contaminated sites.
Passive samplers can be deployed in both freshwater and saltwater systems. The fundamental
processes affecting the uptake of COC by the PE, POM or SPME are essentially the same regardless
of the salinity of the water except for one difference. The presence of the salt dissolved in seawater will
make the COC accumulate into the organic polymer more readily than in freshwater. For example, a
COC at a given dissolved concentration in seawater will accumulate to a greater degree in a passive
sampler deployed in seawater than the same COC at the same dissolved concentration in freshwater.
However, the most substantial difference between freshwater and saltwater systems when passive
sampling is probably the adverse effects to the deployment gear. In saltwater systems, the potential for
corrosion of any metal is obviously much greater than in freshwater systems. The forthcoming
guidance on deploying and recovering passive samplers will discuss considerations for using passive
samplers in saltwater systems.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
12
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Figure 6. Passive samplers
designed for water column
deployments: (a) long strip of
polyethylene on a stainless
steel wire loop, and
(b) polyethylene and
polyoxymethylene strips
fastened to the interior of a
fish trap.
(d)
Figure 7. Passive
samplers designed
for whole
sediment
deployments: (a)
small piece of
polyethylene, (b)
polyethylene
arrayed in a metal
frame, (c) copper
tubing holding
SPME fibers, and
(d) stainless steel
tubing containing
SPME fibers.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
13
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Anchor Line.
iifT pEorp°M
I/// deployed
iJ 11 in fish trap
(Motto Scale)
Figure 8.
Illustrations depicting passive sampler
deployment strategies in the water column
(a,b,c) and sediments (d).
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
14
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
7. Selecting Passive Samplers
Of the three types of passive samplers discussed in this document, each has its own advantages and
disadvantages, and, to a certain extent, each has its own following of practitioners. Table 3 lists some
of the more relevant characteristics of each type of sampler when considering which one to use.
Because they are similar in form (polymer sheets), PE and POM demonstrate several common
advantages. Both PE and POM are relatively inexpensive, rugged, easy to work with (can be cut into
pieces with scissors for deployment), simple to deploy, deployable in large masses, which increases
analytical sensitivity, and are enjoying increased use in the scientific and regulatory communities. In
addition, both PE and POM are effective for water column and sediment deployments. However, PE
and POM have some differences and disadvantages. PE is very flexible and can fold in on itself,
making it difficult to clean, especially after deployment. Conversely, the rigid structure of POM reduces
folding, which makes it easier to clean, but also renders it prone to ripping away from the wire during
the deployment (whereas PE will stretch well before ripping). In contrast to PE and POM, SPME are
believed to achieve equilibrium faster than the other two polymers, which can be a significant
advantage. In addition, SPME, once secured in the protective tubing or casing, are easily deployed,
recovered and cleaned, in part because of their compact size. Furthermore, SPME has wide usage
around the world. However, SPME fibers can be fragile as compared with PE or POM, which affects
ease of handling. It is also difficult to deploy large masses of SPME, which reduces analytical
sensitivity compared with PE or POM. For this reason, SPME can be better suited for deployment in
sediments rather than the water column.
8. Analyzing Passive Sampler Data
Regardless of the type of passive sampler selected for use, analysis of passive sampler data can be
handled in the series of steps described below. As noted in Section 3, passive samplers provide two
types of information:
(1) Measured concentration of COC in the passive sampler
(2) Predicted concentration of COC dissolved around the passive sampler
These types of information can be expressed in several different ways. Examples of the common
concentration units for passive sampler data are shown in Table 4. In general, the laboratory analyzing
the passive samplers will provide data on the amount of contaminant in the passive samplers ([1]
above). Using these data, the following steps can be followed to translate the measured concentrations
in the passive sampler into dissolved concentrations around the passive samplers:
(1) Convert units to micrograms per gram (ug/g):
If the units reported by the laboratory are microgram (ug) COC/milliliter (ml_) sampler, convert the units
to ug COC/g sampler by dividing by the density of the passive sampler. Commonly reported densities
for PE are 0.92 g/mL, for POM are 1.4 g/mL, and for PDMS are 0.97 g/mL.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
15
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
(2) Calculate the dissolved COC concentration:
Using the concentration of COC in the passive sampler in |jg COC/g sampler, the dissolved
concentration (in the water column or interstitial water around the passive sampler) is calculated using
Equation 1:
COCD =
[1]
where COCD is the dissolved concentration (ug COC/L) of a given COC in the surrounding water,
COCps is the concentration of the COC in the passive sampler (ug COC/g sampler) from Step 1, and
KPS-D is the passive sampler-dissolved phase partition coefficient (in liters per kilogram [L/Kg]). A
multiplier of 1,000 is included to address the change in units (1,000 g/Kg). Values for a limited number
of KPS-D are available in the scientific literature. For example, U.S. EPA (2012) provides a set of
provisional KPS.D for a range of hydrophobic contaminants and passive samplers (PE [KPE.D], POM
[KPOM-D], SPME [KSPME-D or KPDMS-D])- In addition, KPS.D can be calculated based on the contaminant's
KOW (see Appendix A). Fortunately, K0w is a fairly common contaminant characteristic available in the
scientific literature (see for example Mackay and others 1992a, b, U.S. EPA 2003, 2008, 2012).
(3) Example Calculation:
Table 5 reports the results of an analysis of PE samplers deployed in the water column for 30 days.
The chemical analyses were for several PAHs, including phenanthrene, benzo[a]pyrene and
benzo[ghi]perylene, the pesticides endrin, toxaphene, DDT, DDE and ODD, and three PCB congeners
(28, 52, 118). The concentrations of the contaminants accumulated by the passive sampler ranged
from 0.07 to 12.5 micrograms per milliliter (ug/mL) PE and 0.08 to 13.6 when converted to ug/g PE.
Using Equation A1 from Appendix A, log KPE-D values were calculated with log K0w from the scientific
literature. Using Equation 1 above, the dissolved concentrations of contaminants were calculated to
range from 0.00002 to 0.841 micrograms per liter (ug/L) or ppb. Multiplying these concentrations by
1,000 converts them to 0.02 to 841 nanograms per liter (ng/L) water or parts per trillion (ppt) (Table 4).
Some general trends can be observed from these example calculations. First, the concentrations of
contaminants accumulating in the passive sampler tend to be higher when the contaminants have lower
log KPE_D values. The concentrations are higher because the lower KPE.D chemicals tend to be more
water soluble than higher KPE.D chemicals. Consequently, the lower K0w chemicals can dissolve into
water more readily than the higher K0w chemicals. Higher concentrations in the water column result in
higher concentrations in the sampler. While the higher K0w chemicals have a greater affinity for
passive sampler polymers (e.g., PE, PDMS or POM) as compared with the low K0w chemicals, this
does not result in elevated concentrations of high K0w chemicals in the passive sampler (Table 5)
because these chemicals must first dissolve into the aqueous phase and then partition into the polymer.
Because of their low solubilities in water, the high K0w contaminants do not dissolve very readily and
therefore do not accumulate to high concentrations in the samplers. The same sort of example
calculations could be performed on contaminants measured in sediment interstitial water.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
16
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Table 3. Advantages and disadvantages of different types of passive samplers.
Passive Sampler
Advantages
Disadvantages
Polyethylene
Polyoxymethylene
Solid Phase Micro-
extraction
Inexpensive polymer
Robust and rugged
Easy to work with
Simple to deploy and recover
Not limited by sample mass
(greater analytical sensitivity)
Will stretch during deployment
before it rips
Increasing use globally
Good for both water column and
sediment deployments
Inexpensive polymer
Robust and rugged
Easy to work with
Simple to deploy and recover
Not limited by sample mass
(greater analytical sensitivity)
Cleans easily
Increasing use globally
Good for both water column and
sediment deployments
Inexpensive polymer fibers
Rapid equilibrium
Widely used globally
Once protected, simple to deploy
and recover
Clean easily
Good for sediment deployments
Slower equilibration than SPME
Folds on itself, making cleaning
difficult
Slower equilibration than SPME
Can rip easily compared with PE
Fragile - need to protect during
deployment
Relatively difficult to handle
Limited polymer mass (less
analytical sensitivity)
Poor for water column deployments
because of the limited polymer mass
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
17
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Table 4. Type of data and units provided by passive samplers.
Type of Data
(1) Concentration of COC in the passive sampler
(2) Concentration of COC dissolved around the
passive sampler
ug COC/mL sampler (ppm1)
ug COC/g sampler (ppm)
ug COC/mL water (ppm)
ug COC/L water (ppb2)
mg COC/L water (ppm)
ng COC/L water (ppt3)
pg COC/L water (ppq4)
1 parts per million,2 parts per billion,3 parts per trillion,4 parts per quadrillion
Table 5. Example calculation of dissolved concentrations of selected contaminants of concern
(COC) based on concentrations measured in a polyethylene passive sampler.
Measured
Concentration
in Sampler
Log KQ
(L/Kg)
Log KPE.D
(L/Kg PE)fc
Calculated Dissolved
Concentration (COCD)
(ng/L)c
Phenanthrene
Benzo[a]pyrene
Benzo[ghi]perylene
Endrin
Toxaphene
PCB28
PCB52
PCB118
p,p' DDT
p,p' DDE
p,p' DDD
(COCps)
(ug/mL)
12.5
3.45
0.75
10.3
8.95
4.98
0.78
0.08
0.43
0.07
0.54
(COCps)
(ug/g)a
13.6
3.75
0.81
11.2
9.73
5.41
0.85
0.08
0.47
0.08
0.59
4.57
6.11
6.51
5.06
5.50
5.67
5.84
6.74
6.53
6.76
6.10
4.21
5.83
6.25
4.72
5.19
5.36
5.54
6.49
6.27
6.51
5.82
841
5.60
0.46
212
63.5
23.4
2.44
0.03
0.25
0.02
0.90
' COCps * mL/0.92 g
Equation 1 * 1,000 to report as ng/L
Log
= -0.59 + 1 .05*Log K
ow
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
18
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
9. BriefCase Study
The Palos Verdes Shelf Superfund site is located in more than 50 meters of water off the coast of Los
Angeles (Figure 9). The site has been contaminated by historic discharges from four effluent pipes
from the Los Angeles County Sanitation Districts since 1937. As a result, the sediments along the shelf
are contaminated with PCBs and DDTs, and the area was designated a Superfund site in 1989.
Ingestion of contaminated fish by humans and wildlife are the risk drivers (U.S. EPA 2009).
In 2007, EPA decided to use passive samplers to measure the dissolved concentrations of PCBs in the
water column above the contaminated sediments (Burgess and others 2011). The conceptual model
for the site suggests contaminants in the sediments enter the water column and are bioavailable to site
fish. Because of the depth of the water column at much of the site and the low dissolved contaminant
concentrations, the use of conventional water sampling methods was not viable. Polyethylene passive
samplers were therefore deployed at seven stations (Figure 9) a few meters above the sediment
surface and allowed to equilibrate for approximately 4
months. Using the approach discussed in Section 8,
dissolved concentrations of PCBs in the water column
were calculated. Figure 10 reports the concentrations of
total dissolved PCBs at the seven stations. There were
not any problems detecting the contaminants in the
passive samplers because the PE samplers accumulated
and concentrated the PCBs over the 4-month
equilibration period. As expected, the concentrations of
PCBs in the passive samplers reflected the
concentrations of contaminants in the sediments; that is,
if sediments were highly contaminated, then the water
column concentrations were also contaminated. For
example, stations B3A, B3B and B5 are located above
the most contaminated sediments and demonstrated the
highest concentrations in the passive samplers (Figure
10). Furthermore, from a regulatory perspective, the
dissolved concentrations could be used to compare with
water quality standards. In this case, the calculated dissolved concentrations for total PCBs were
contrasted with the ambient water quality criteria (AWQC) based on aquatic life and human health. The
dissolved concentrations ranged from 100 to 800 picograms/liter (pg/L) or parts per quadrillion. The
aquatic life AWQC for total PCBs is 30,000 pg/L and was clearly not exceeded at any station.
However, the human health AWQC based on fish consumption is only 64 pg/L and every station
exceeded that criterion value. The planned remediation of the Palos Verdes Shelf Superfund site
should reduce these concentrations in the water column. As a result of the successful use of passive
samplers here, they will also be used to evaluate the effects of site remediation on the water column
concentrations of PCBs and DDTs during and after remediation (capping the most heavily
Figure 9. Locations of passive sampler
deployment stations at the Palos
Verdes Shelf Superfund site.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
19
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
contaminated areas). While this brief case study focused on water column concentrations, similar
analysis of sediment interstitial water concentrations of contaminants is also viable.
IT 30,000 ______________ __
en
CL
O
o
o
I
"c
o
o
c
o
o
CD
O
Q_
~o
O)
1000
800
600
Aquatic Life
AWQC
400
200
Human Health
AWQC
B6A
B6B
Station
Figure 10. Concentrations of dissolved total PCBs in the water column at the
Palos Verdes Shelf Superfund site passive sampler deployment stations.
10. Remaining Scientific Challenges in Using Passive Samplers
A great deal of confidence exists in the utility of passive sampling at Superfund sites. As noted,
passive samplers provide information about the concentrations of contaminants in the samplers that
can be used to more accurately predict the bioavailable concentrations in the surrounding water column
or interstitial waters. However, a few outstanding scientific challenges exist that may limit their wide
spread acceptance and use. First, it is critical to determine when a contaminant has achieved
equilibrium between the dissolved phase and the sampler and any other environmental phases present.
Currently, there are approaches available to decide when equilibrium has been reached, but there
exists the need to better understand how and when equilibrium occurs and to have alternative options
for evaluating concentration data when equilibrium does not occur. Information Box #4 explains some
of the available approaches for obtaining equilibrium information.
A second scientific challenge deals with interpreting the meaning of contaminant accumulation by
passive samplers. As noted, some studies have suggested that passive samplers accumulate COC in
ways similar to benthic organisms (Vinturella and others 2004, Friedman and others 2009, Gschwend
and others 2011). In theory, this suggestion makes a great deal of sense because the lipid in
organisms, where COC accumulate, is chemically similar in partitioning behavior to the polymers used
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
20
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
for passive samplers, and many benthic
invertebrates receive their exposures from
contaminants dissolved in the interstitial water.
Additional laboratory and field research is needed
to better understand the relationship between
passive sampler accumulation and organism
bioaccumulation. This research could result in a
statistically robust but simple linear model that
predicts organism bioaccumulation based on
knowing how much COC accumulated in a passive
sampler (COCPS). Furthermore, risk at Superfund
sediment sites is often driven by adverse effects to
human health by the consumption of contaminated
fish and shellfish. At this point, using passive
samplers to predict concentrations of COC in
pelagic fish is especially challenging because of
the potential for trophic transfer and exposure to
sources of COC other than from the site
sediments. In other words, while there is evidence
passive samplers can serve as surrogates for
benthic organisms, more research is needed
before a similar statement can be made about
pelagic fish. However, it is feasible that passive
sampler-based dissolved concentrations could be
input into a bioaccumulation model (Gobas 1993,
Gobas and Arnot 2010) to predict concentrations in
edible fish tissue.
Finally, there is a need to develop a standard set
of passive sampler-dissolved phase partition
coefficients (KPS-D) for a range of passive samplers
and COC. As discussed, this partition coefficient is
used in Equation 1 to estimate the dissolved
concentration of COC. These partition coefficients
are available in the scientific literature and can also
be calculated based on K0w- This need is not so
much a scientific challenge as a task to compile
scientifically-sound values that can be used
universally and consistently by the entire passive
sampling community.
Information Box 4 Performance Reference
Compounds (PRCs) As discussed in this
document, passive samplers accumulate COC
until equilibration has been achieved between the
various environmental phases. However,
determining when equilibrium has been achieved
is challenging. One approach is to deploy the
samplers for an extended period of time (e.g., 28
days) and assume the samplers are at equilibrium.
Conversely, another approach is to collect
subsamples of the passive samplers overtime and
plot the concentration of contaminants (COCPS)
versus time and empirically identify when
equilibrium is reached. Both of these approaches
are viable but have disadvantages. The first
approach requires an assumption that will often be
wrong for the higher molecular weight, more
hydrophobic COC that require more than 28 days
to achieve equilibrium. The second approach is
expensive and may not always be logistically
feasible. A third approach developed by Huckins
and others (2002) is to add chemicals (PRCs) to
the passive samplers at the start of the
deployment. These PRCs are selected to behave
like the target COC except that, as the passive
sampler absorbs target COC, the sampler is also
releasing PRCs at similar rates. Because the
PRCs are selected to behave like the target COC,
by knowing how much PRC was present at the
start of the deployment and how much remains at
the end (which are both easily measured), and
using some algebra, the equilibrium status of each
COC can be calculated. For example, based on
PRC data, a specific PCB congener is found to be
89 percent equilibrated after 28 days. By adjusting
the measured PCB congener concentration
upward by 11 percent, the actual concentration at
equilibrium is predicted. The advantages and
disadvantages of PRCs are currently being
assessed.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
21
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
11. U.S. EPA Contacts Working with Passive Samplers
Table 6 provides a list of U.S. EPA contacts working with passive samplers. These personnel may be
contacted to provide technical assistance and site-specific advice on the use of passive samplers at
sites around the United States.
12. Summary
Passive samplers are site assessment and monitoring tools that can provide faster, cheaper, and more
scientifically-sound information about the dissolved water column and interstitial water concentrations of
hydrophobic organic COC at Superfund sites. Often passive samplers are more effective at
determining accurately the bioavailable concentrations of COC than the application of conventional
sampling techniques. This passive sampler-based information can be used to better understand
contaminant concentrations that result in real exposures and risks at Superfund sites. However,
passive samplers do not provide information about the concentrations of COC associated with bedded,
suspended or colloidal particles in aquatic systems and therefore do not address the transport of
contaminants associated with such particles. The technology for using passive sampling to evaluate
exposures to metals is still under development and was not discussed in this document. Because of
the many advantages over conventional sampling, passive sampling is likely to have an increasingly
important role in the future of environmental sampling as more guidance and standard operating
procedures become available. Furthermore, the availability of contract laboratories with the capability
to deploy passive samplers and analyze them after deployment is also increasing as passive sampling
becomes more routine.
Table 6. List of U.S. EPA contacts working with passive samplers.
Name
Robert Burgess
Passive Sampler
Application Office and Location
Water column and
sediments
deployments:
Performance of different
passive samplers; Use
of performance
reference compounds;
Relationship to
organism
bioaccumulation
ORD/NHEERL/
AED-Narragansett,
Rl
e-mail
burgess.robert@epa.gov
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
22
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Name
Lawrence Burkhard
Mark Cantwell
Bruce Duncan
Marc Greenberg
Judy Huang
Matthew Lambert
Marc Mills
Passive Sampler
Application
Sediment deployment:
Relationship to
organism
bioaccumulation
Water column
deployments in riverine
systems: COC and
emerging contaminants
Use of passive
samplers at Superfund
sites
Use of passive sampler
information for decision
making
RPM for Palos Verdes
Shelf site deploying
passive samplers
Sediment deployments:
Evaluate contaminant
partitioning and
bioavailability; Passive
sampler use in baseline
and remedy
effectiveness
monitoring
Water column and
sediment deployments:
Source tracking and
identification;
Relationship to
organism
bioaccumulation;
Emerging contaminants
Office and Location
ORD/NHEERL/MED-
Duluth, MN
ORD/NHEERL/
AED-Narragansett,
Rl
Region 10-Seattle,
WA
OSWER/OSRTI/
ERT-Edison, NJ
Region 9 -
San Francisco, CA
OSWER/OSRTI
Washington, DC
ORD/NRMRL/
LRPCD-Cincinnati,
OH
e-mail
burkhard.lawrence@epa.gov
cantwell. mark@epa.gov
duncan.bruce@epa.gov
greenberg.marc@epa.gov
huang.judy@epa.gov
lambert.matthew@epa.gov
mills.marc@epa.gov
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
23
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Joseph Schubauer-
Berigan
Sean Sheldrake
Rachelle Thompson
Water column
deployments:
Restoration and risk
management
evaluations and
applications;
Comparison of different
passive samplers
Diving Officer; Passive
sampler deployment
techniques and diver
related QA/QC issues
RPM for United
Heckathorn site
deploying passive
samplers
ORD/NRMRL/
LRPCD-Cincinnati,
OH
schubauer-
berigan.joseph@epa.gov
Region 10 - Seattle,
WA
Region 9 -
San Francisco, CA
sheldrake.sean@epa.gov
thompson.rachelle@epa.gov
13. Acknowledgements
The lead author of this document was Robert Burgess (U.S. EPA, Narragansett, Rl). Robin Anderson
(U.S. EPA, OSRTI, Washington, DC), Mark Cantwell (U.S. EPA, ORD, Narragansett, Rl), Helen
Dawson (U.S. EPA, OSRTI, Washington, DC), Bruce Duncan (U.S. EPA Region 10, Seattle, WA),
Stephen Ells (U.S. EPA, OSRTI, Washington, DC), Loretta Fernandez (NRC/U.S. EPA, Narragansett,
Rl), Karl Gustavson (U.S. Army Corps of Engineers, Washington, DC), Kymberlee Keckler (U.S. EPA,
Region 1, Boston, MA), Matthew Lambert (U.S. EPA, OSRTI, Washington, DC), Kira Lynch (U.S. EPA
Region 10, Seattle, WA), Leslie Mills (U.S. EPA, Narragansett, Rl), Wayne Munns (U.S. EPA,
Narragansett, Rl), Monique Perron (NRC/U.S. EPA, Narragansett, Rl), Sean Sheldrake (U.S. EPA
Region 10, Seattle, WA), and Randy Sturgeon (U.S. EPA, Region 3, Philadelphia, PA) provided
insightful technical reviews of this document. Members of the U.S. EPA's Groundwater Forum are also
thanked for their review of the document. The following individuals are thanked for providing images for
this document: Loretta Fernandez, Philip Gschwend (MIT, Cambridge, MA), Steve Hawthorne
(University of North Dakota, Grand Forks, ND, USA), Rainer Lohmann (University of Rhode Island,
Narragansett, Rl), Keith Maruya (Southern California Coastal Waters Research Project, Costa Mesa,
CA), Monique Perron, and Danny Reible (University of Texas, Austin, TX). Patricia DeCastro (SRA,
Narragansett, Rl) and Younus Burhan (Tetra Tech, Reston, VA) are thanked for their editing and the art
work prepared for this document. In addition, an independent laboratory is thanked for its estimates of
the costs associated with the chemical analysis of various types of samples.
Questions regarding this document should be forwarded to Robert Burgess (burgess.robert@epa.gov)
or Stephen Ells (ells.steve@epa.qov). This is U.S. EPA ORD/NHEERL Atlantic Ecology Division
contribution number AED-11-097.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
24
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
14. References Used in this Document
Booij, K., J.R. Hoedemaker, and J.F. Bakker. 2003. Dissolved PCBs, PAHs and HCB in pore waters
and overlying waters of contaminated harbor sediments. Environ Sci Technol 34:5177-5183.
Burgess, R.M., R. Lohmann, P. Luey, M. Charpentier, M. Noble, K.J. Rosenberger, C.R. Sherwood,
and C. White. 2011. Use of polyethylene passive samplers to estimate water column PCB
concentrations at the Palos Verdes Superfund prior to remediation. Platform presentation at the
Battelle Sixth International Conference on Remediation of Contaminated Sediments. New Orleans,
LA, USA.
Burton, G.A., G. Rosen, D.B. Chadwick, M.S. Greenberg, W.K. Taulbee, G.R. Lotufo, and D.D. Reible.
2012. A sediment ecotoxicity assessment platform for in situ measures of chemistry,
bioaccumulation and toxicity. Part 1: System description and proof of concept. Environ Poll 162:449-
456.
DiFilippo, E.L., and R.P. Eganhouse. 2010. Assessment of PDMS-water partition coefficients:
implications for passive environmental sampling of hydrophobic organic compounds. Environ Sci
Technol 44:6917-6925.
Endo, S., S.E. Hale, K-U. Goss, and H.P.H. Arp. 2011. Equilibrium partition coefficients of diverse polar
and nonpolar organic compounds to polyoxymethylene (POM) passive sampling devices Environ Sci
Technol 45:10124-10132.
Fernandez, L.A., J.K. MacFarlane, A.P. Tcaciuc, and P.M. Gschwend. 2009. Measurement of freely
dissolved PAH concentrations in sediment beds using passive sampling with low-density
polyethylene strips. Environ Sci Technol 43:1430-1436.
Friedman, C.L., R.M. Burgess, M.M. Perron, M.G. Cantwell, K.T. Ho, and R. Lohmann. 2009.
Comparing polychaete and polyethylene uptake to assess sediment resuspension effects on PCB
bioavailability. Environ Sci Technol 43:2865-2870.
Gobas, F.A.P.C. 1993. A model for predicting the bioaccumulation of hydrophobic organic chemicals in
aquatic food-webs: application to Lake Ontario. Ecol Model 69:1-17.
Gobas, F.A.P.C. and J. Arnot. 2010. Food web bioaccumulation model for polychlorinated biphenyls in
San Francisco Bay, California. Environ Toxicol Chem 29:1385-1395.
Gschwend, .P.M, J.K. MacFarlane, D.D. Reible, X. Lu, S.B. Hawthorne, D.V. Nakles, and T. Thompson.
2011. Comparison of polymeric samplers for accurately assessing PCBs in pore waters. Environ
Toxicol Chem 30:1288-1296.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
25
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Hawthorne, S.B., C.B. Grabanski, D.J. Miller, and J.P. Kreitinger. 2005. Solid-phase microextraction
measurement of parent and alkyl polycyclic aromatic hydrocarbons in milliliter sediment pore water
samples and determination of KDoc values. Environ Sci Technol 39:2795-2803.
Hawthorne, S.B., D.J. Miller, and C.B. Grabanski. 2009. Measuring low picogram per liter
concentrations of freely dissolved polychlorinated biphenyls in sediment pore water using passive
sampling with polyoxymethylene. Anal Chem 81:9472-9480.
Huckins, J.N., G.K. Manuweera, J.D. Petty, D. Mackay, and J.A. Lebo. 1993. Lipid-containing
semipermeable membrane devices for monitoring organic contaminants in water. Environ Sci
Technol 27:2489-2496.
Huckins, J.N., J.D. Petty, J.A. Lebo, F.V. Almeida, Kooij, D.A. Alvarez, W.L. Cranor, R.C. Clark, and
B.B. Mogensen. 2002. Development of the permeability/performance reference compound approach
for in situ calibration of semipermeable membrane devices. Environ Sci Technol 36:85-91.
Huckins, J.N, J.D. Petty, and K. Booij. 2006. Monitors of Organic Chemicals in the Environment.
Springer, New York, NY, USA.
Janssen, E.M.L., A.M.P. Oen, S.N. Luoma, and R.G. Luthy. 2011. Assessment of field-related
influences on polychlorinated biphenyl exposures and sorbent amendment using polychaete
bioassays and passive sampler measurements. Environ Toxicol Chem 30:173-180.
Lampert, D.J., W.V. Sarchet, and D.D. Reible. 2011. Assessing the effectiveness of thin-layer sand
caps for contaminated sediment management through passive sampling. Environ Sci Technol
45:8437-8443.
Lohmann, R., and D. Muir. 2010. Global aquatic passive sampling (AQUA-GAPS): Using passive
samplers to monitor POPs in the waters of the world. Environ Sci Technol 44:860-864.
Lu, X., B. Drake, A. Skwarski, and D. Reible. 2011. Predicting bioavailability of PAHs and PCBs with
pore water concentrations measured by disposable solid-phase micro-extraction fibers. Environ
Toxicol Chem 30:1109-1116.
Mackay, D., W.Y. Shiu, and K.C. Ma. 1992a. Illustrated handbook of physical-chemical properties and
environmental fate for organic chemicals. Volume II - Polynuclear aromatic hydrocarbons,
polychlorinated dioxins and dibenzofurans. Lewis Publishers, Boca Raton, FL, USA.
Mackay, D., W.Y. Shiu, and K.C. Ma. 1992b. Illustrated handbook of physical-chemical properties and
environmental fate for organic chemicals. Volume I - Monoaromatic hydrocarbons, chlorobenzenes,
and PCBs. Lewis Publishers, Boca Raton, FL, USA.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
26
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Maruya, K.A., E.Y. Zeng, D. Tsukada, and S. Bay. 2009. A passive sampler based on solid-phase
microextraction for quantifying hydrophobia organic contaminants in sediment pore water. Environ
Toxicol Chem 28:733-740.
Mayer, P., W.J. Vaes, F. Wijnker, K. Legierse, R. Kraaij, J. Tolls, and J.M. Hermens. 2000. Sensing
dissolved sediment pore water concentrations of persistent and bioaccumulative pollutants using
disposable solid-phase microextraction fibers. Environ Sci Technol 34:5177-5183.
Oen, A.M.P., E.M.L. Janssen, G. Cornelissen, G.D. Breedveld, E. Eek, and R.G. Luthy. 2011. In situ
measurement of PCB pore water concentration profiles in activated carbon-amended sediments
using passive samplers. Environ Sci Technol 45:4053-4059.
Reichenberg, F., and P. Mayer. 2006. Two complementary sides of bioavailability: accessibility and
chemical activity of organic contaminants in sediments and soils. Environ Toxicol Chem 25:1239-
1245.
Schubauer-Berigan, J.P., E.A. Foote, and V.S. Magar. 2012. Using SPMDs to assess natural recovery
of PCB-contaminated sediments in Lake Hartwell, SC: I. A field test of new in-situ deployment
methods. So/7 Sec! Contamin 21:82-100.
Schwarzenbach, R.P., P.M. Gschwend, and D.M. Imboden. 2003. Environmental Organic Chemistry.
Wiley-lnterscience. Hoboken, NJ, USA.
Tomaszewski, J.E., and R.G. Luthy. 2008. Field deployment of polyethylene devices to measure PCB
concentrations in pore water of contaminated sediment. Environ Sci Technol 42:6086-6091.
U.S. Environmental Protection Agency (EPA). 2003. Procedures for the derivation of equilibrium
partitioning sediment benchmarks (ESBs) for the protection of benthic organisms: PAH mixtures.
EPA-600-R-02-013. Office of Research and Development, Washington, DC, USA.
U.S. EPA. 2008. Procedures for the derivation of equilibrium partitioning sediment benchmarks (ESBs)
for the protection of benthic organisms: compendium of tier 2 values for nonionic organics. EPA-600-
R-02-016. Office of Research and Development. Washington, DC, USA.
U.S. EPA. 2009. Palos Verdes Shelf Superfund Site: EPA announces proposed plan.
http://www.epa.gov/region09/features/pvshelf/.
U.S. EPA. 2012. Equilibrium partitioning sediment benchmarks (ESBs) for the protection of benthic
organisms: procedures for the determination of the freely dissolved interstitial water concentrations
of nonionic organics. EPA-600-R-02-012. Office of Research and Development, Washington, DC,
USA.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
27
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Vinturella, A.E., R.M. Burgess, B.A. Coull, K.M. Thompson, and J.P. Shine. 2004. The use of passive
samplers to mimic uptake of polycyclic aromatic hydrocarbons by benthic polychaetes. Environ Sci
7ec/?no/38:1154-1160.
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
28
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Appendix A. Provisional passive sampler - dissolved phase partition coefficients (KPS-D) (L/Kg)
for selected hydrophobic contaminants.
Class
PAHs
Contaminants
Naphthalene
C1 -naphthalenes
Acenaphthylene
Acenaphthene
C2-naphthalenes
Fluorene
CS-naphthalenes
Anthracene
Phenanthrene
C1-fluorenes
C4-naphthalenes
C1-phenanthrene/anthracenes
C2-fluorenes
Pyrene
Fluoranthene
C2-Phenanthrene/anthracenes
C3-fluorenes
C1-pyrene/fluoranthenes
C3-phenanthrene/anthracenes
Benz(a)anthracene
Chrysene
C4-Phenanthrenes/anthracenes
C1-Benzanthracene/chrysenes
Benzo(a)pyrene
Perylene
Benzo(e)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
C2-benzanthracene/chrysenes
Benzo(ghi)perylene
C3-benzanthracene/chrysenes
lndeno(1 ,2,3-cd)pyrene
Dibenz(a,h)anthracene
C4-benzanthracene/chrysenes
LogKpE3
2.93
3.40
2.79
3.62
3.93
3.83
4.45
4.17
4.21
4.37
4.98
4.70
4.87
4.58
4.75
5.14
5.40
4.96
5.63
5.37
5.41
6.05
5.86
5.83
5.85
5.85
5.99
6.02
6.16
6.25
6.70
6.47
6.46
7.14
Log KPOM b
2.79
3.24
2.66
3.45
3.74
3.65
4.25
3.98
4.02
4.17
4.75
4.49
4.65
4.37
4.53
4.91
5.16
4.74
5.38
5.13
5.17
5.78
5.60
5.57
5.60
5.60
5.73
5.75
5.89
5.97
6.41
6.19
6.18
6.83
Log KSPME °
2.86
3.22
2.75
3.40
3.64
3.56
4.05
3.83
3.86
3.99
4.47
4.25
4.39
4.16
4.29
4.60
4.80
4.46
4.98
4.78
4.81
5.32
5.17
5.14
5.16
5.16
5.27
5.29
5.41
5.47
5.83
5.65
5.64
6.18
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
29
OSWER Directive 9200.1-110 FS
December 2012
-------
Guidelines for Using Passive Samplers to Monitor Organic Contaminants at Superfund Sediment Sites
Class
Other
Chemicals
Contaminants
Benzene
Delta-BHC
Gamma-BHC, Lindane
Biphenyl
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
Chlorobenzene
Diazinon
Dibenzofuran
1 ,2-Dichlorobenzene
1 ,3-Dichlorobenzene
1 ,4-Dichlorobenzene
Di-n-butyl phthalate
Dieldrin
Diethyl phthalate
Endosulfan mixed isomers
Alpha-Endosulfan
Beta-Endosulfan
Endrin
Ethylbenzene
Hexachloroethane
Malathion
Methoxychlor
Pentachlorobenzene
1 ,1 ,2,2-Tetrachloroethane
Tetrachloroethene
Tetrachloromethane
Toluene
Toxaphene
Tribromomethane (Bromoform)
1 ,2,4-Trichlorobenzene
1,1, 1-Trichloroethane
Trichloroethene
m-Xylene
LogKpE3
1.65
3.38
3.33
3.57
4.66
4.49
2.41
3.30
3.68
3.01
3.01
3.00
4.25
5.05
2.04
3.72
3.43
4.16
4.72
2.71
3.61
2.44
4.74
4.93
1.92
2.21
2.28
2.30
5.19
1.88
3.62
2.01
2.26
2.77
Log KPOM b
1.55
3.22
3.17
3.40
4.45
4.29
2.29
3.14
3.51
2.86
2.86
2.85
4.06
4.82
1.93
3.54
3.27
3.97
4.51
2.57
3.44
2.32
4.53
4.71
1.81
2.10
2.16
2.18
4.96
1.77
3.45
1.90
2.14
2.63
Log KSPME °
1.84
3.21
3.17
3.36
4.22
4.09
2.44
3.14
3.45
2.92
2.92
2.91
3.90
4.53
2.15
3.47
3.25
3.82
4.27
2.68
3.39
2.47
4.29
4.44
2.05
2.29
2.34
2.35
4.64
2.02
3.40
2.13
2.32
2.73
a Log KPE_D = -0.59 + 1.05 Log Kow (Equation A1) (Lohmann and Muir 2010)
b Log KPOM_D = -0.60 + 1.01 Log Kow (Equation A2) (Endo and others 2011)
cLogKSPME_D = 0.07 + 0.83 LogKow (Equation A3) (DiFilippo and Eganhouse 2010)
United States
Environmental Protection
Agency
Office of Superfund Remediation and
Technology Innovation, and
Office of Research and Development
30
OSWER Directive 9200.1-110 FS
December 2012
------- |