United States
Environmental Protection
Agency
National Exposure
Research Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/SR-96/098 August 1996
Project Summary
v>EPA
Evaluation and Selection of
Analytical Methods for Lawn-
Applied Pesticides
Marcia G. Nishioka, Marielle C. Brinkman, and Hazel M. Burkholder
The work described in this report
summarizes four different surveys that
were conducted. The first two surveys
were conducted to identify the lawn
pesticides, including herbicides, insec-
ticides, and fungicides, used in the Co-
lumbus, Ohio area by professional lawn
care companies and home owners, re-
spectively. The third survey was con-
ducted to identify through literature
publications available methods for
analysis of 12 different lawn-applied
pesticides that were identified in the
first two surveys. The fourth survey, a
literature search, was conducted to
identify the major soil metabolites of
four herbicide acids. Data from the two
literature searches have been ab-
stracted and compiled into separate
databases using Borland's Paradox
(DOS) software.
Methods reported in the literature
may not be appropriate for anticipated
EPA pesticide studies in track-in and
intra-home redistribution. Published
methods are not specific to the matri-
ces of interest here (house dust,
entryway soil, and polyurethane foam
collected carpet and turf surface-
dislodgeables). Potential interferences
and co-extracted species such as hu-
mic acids, aliphatic fatty acids, lipids,
phenols, PAH and other combustion
source-derived species are not ad-
dressed.
This Project Summary was developed
by EPA's National Exposure Research
Laboratory, Research Triangle Park, NC,
to announce key findings of the re-
search project that is fully documented
in a separate report of the same title
(see Project Report ordering informa-
tion at back).
Introduction
Various pesticides have been identified
in house dust and indoor air. In at least
one case, the presence in the home of
several pesticides (e.g. chlorpyrifos,
diazinon, o-phenylphenol) was clearly due
to indoor use of whole room foggers and
sprays. The presence of other pesticides
appeared to be due to infiltration and mi-
gration into the home of pesticides that
were originally applied to foundations,
walkways, and gardens (e.g. permethrin,
chlordane, heptachlor). Infiltration through
foundation cracks probably explains the
presence of chlordane indoors in many
older homes and may be similar to radon
infiltration. However, for pesticides such
as permethrin, which are applied at sites
distant from the foundation, track-in of con-
taminated soil on shoes may explain the
presence of these outdoor-applied pesti-
cides in the home.
House dust may be a more complex
matrix than soil or plant material, as other
human and combustion source-derived
pollutants will be encountered (e.g. fatty
acids, lipids, phenols, PAH, carpet addi-
tives). The ease in applying standard soil
analysis methods to house dust samples
for outdoor applied pesticides will be com-
promised further by pesticide levels that
are expected to be significantly lower due
to the dilution that occurs during any migra-
tion process. Therefore, methods suitable
for outdoor levels are unlikely to be suit-
able for lower indoor levels in a specific
matrix like house dust.
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Conclusions
The primary lawn-care pesticides ap-
plied in the Columbus area are preemer-
gence and post-emergence herbicides.
The most frequently used preemergence
herbicides are the dinitro-aniline deriva-
tives pendimethalin, benfluralin, and triflu-
ralin. The latter two are often combined in
a mixture for application (trade name
Team).
The most frequently used post-emer-
gence herbicides are the acid herbicides,
dicamba, 2,4-dichlorophenoxyacetic acid
(2,4-D), mecoprop (or MCPP), and 2-me-
thyl-4-chloro-phenoxyacetic acid (MCPA).
Dicamba, 2,4-D, and mecoprop are fre-
quently combined for application (trade
name Trimec, among others). Recent con-
cern over possible adverse health effects
from 2,4-D exposure has prompted sev-
eral of the larger lawn-care companies to
replace the 2,4-D with MCPA in the Trimec
or Trimec-equivalent formulations.
Applications of insecticides and fungi-
cides vary widely in Columbus. These ap-
plications depend on the particular com-
pany and the general weather patterns. At
least one company routinely applies an
insecticide with herbicides. Mild winters
and/or cool, wet weather increase the use
of fungicides and insecticides. Other com-
panies report that they have not applied
fungicides in several years.
A previous study of pesticides in house
dust stated that house dust extracts
caused significant problems for "in con-
trol" GC quantification. Because problems
of this nature were not identified in analy-
ses of soil samples, we have to assume
that soil and house dust are distinctly dif-
ferent in composition and that the com-
plexity of house dust extracts requires
more rigorous analytical methods, espe-
cially cleanup steps. Methods that have
been reported in the literature cannot be
recommended for anticipated pesticide
studies in track-in and intra-home redistri-
bution because they do not address the
matrices of interest, do not provide suffi-
cient cleanup steps, and, thus, do not
have the requisite sensitivity. Published
methods generally address the less com-
plex matrices of soil and water.
From the standpoint of analysis meth-
odology alone, the published methods 1)
allude to difficulties in dealing with co-
extracted humic acids without providing
solutions, 2) provide little or no sample
cleanup, 3) detail excessive artifact forma-
tion during derivatization steps, 4) obtain
low recovery of analytes from clay-like
soils, 5) provide insufficient detection lim-
its, and/or 6) rely on relatively high-cost
GC/MS analyses rather than lower-cost
GC selective detector analyses.
Appropriate trace analysis methods
need to be developed for the herbicide
acids, the dinitro-aniline herbicides and
moderately polar insecticides/fungicides,
and glyphosate in house dust, entry-way
soil, and dislodgeable residues. These
methods need to address cleanup of co-
extracted humic acids, fatty acids, lipids,
and other neutral co-extracted organics.
Target detection limits of 10-100 ppb in
dust and soil are anticipated for studies of
the migration of lawn-applied pesticides.
Extraction methods developed for dust and
soil need to be compatible with the PUF
polymeric structure, so that only a simple
scaling factor is needed to adapt dust
methods to PUF-collected surface-
dislodgeables. Proposed analysis meth-
ods for dust and soil are detailed in this
report.
The literature survey of herbicide acid
soil metabolites indicated that major me-
tabolites are either acidic or phenolic spe-
cies. For the chlorophenoxy herbicide ac-
ids (2,4-D, mecoprop, and MCPA) the
dominant metabolite is the phenol that
results after cleavage of the alkanoic side
chain (e.g. 2,4-dichlorophenol from 2,4-
D). Because of the similarity in polarity
between herbicide and metabolite, both
species may be analyzed using a single
method. This approach is routinely used
in studies of glyphosate, where both par-
ent and its metabolite, aminomethyl-
phosphonic acid, are monitored.
Recommendations
We recommend that the analysis meth-
ods proposed in this report be evaluated
for application to the respective pesticide
classes with regard to recovery, precision,
and accuracy in the three matrices of in-
terest. The analysis methods should be
evaluated for detection and quantification
at trace (10-100 ppb) levels in house dust,
high clay content entry-way soil, and PUF-
collected surface dislodgeables.
This report was submitted in partial ful-
fillment of Contract No. 68-DO-007 by
Battelle Columbus Operations under spon-
sorship of the U.S. Environmental Protec-
tion Agency.
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Marcia Nishioka, Marielle Brinkman, and Hazel Burkholder are with Battelle,
Columbus, OH 43201
Robert G. Lewis is the EPA Project Officer (see below).
The complete report, entitled "Evaluation and Selection of Analytical Methods for
Lawn-Applied Pesticides," (Order No. PB96-199559; Cost: $25.00, 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:
National Exposure Research Laboratory
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
United States
Environmental Protection Agency
National Risk Management Research (G-72)
Cincinnati, OH 45268
Official Business
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