United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
Las Vegas NV 89193-3478
Research and Development
EPA/600/S4-91/025 March 1992
EPA Project Summary
Indoor Air Pollutants from
Household Product Sources
Thomas M. Sack and David H. Steele
A collection of GC/MS data obtained
during the analysis of 1,159 household
products for six common chlorocarbon
solvents has been reanalyzed for the
presence and concentration of 25 addi-
tional chemicals. Using computerized
GC/MS software, 1,043 of the original
GC/MS data files were recovered and
analyzed for the presence of the addi-
tional chemicals. An efficient microcom-
puter-based data base system was de-
veloped and used to assemble, reduce,
and view the analytical data.
Of the 25 additional chemicals, those
found most frequently in the house-
hold products include acetone, 2-
butanone, methylcyclohexane, toluene,
ethylbenzene, m-xylene, and o,p-xylene.
A total of 63.6% of the products ana-
lyzed in this study contained one or
more of the 25 additional analytes at
concentrations greater than or equal to
0.1% by weight. Fivis analytes, 1,1,2,2-
tetrachloroethane, chlorobenzene, sty-
rene, nonane, and d-limonene, were not
found in any of the products in con-
centrations greater than or equal to
0.1% by weight.
The major accomplishment of this
work is the completion of a large data
base of semiquantitative information for
31 chemicals in the home environment.
The quantitative information presented
in the report is available on diskette in
a spreadsheet format.
This Project Summary was developed
by EPA's Environmental Monitoring
Systems Laboratory, Las Vegas, NV, 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
Since most people spend a large
amount of time indoors at either home or
at work, in often insufficiently ventilated
buildings, there is an increasing concern
about the presence of toxic vapors in in-
door air. To address this issue, the Office
of Pesticides and Toxic Substances
(OPTS) and the Office of Air and Radia-
tion (OAR) of the U.S. Environmental Pro-
tection Agency (USEPA) have been work-
ing to define pollutants and their levels
and sources in indoor air, particularly in
residential settings. In addition, the Office
of Solid Waste and Emergency Response
(OSWER), under the authority of the Su-
perfund Amendments and Reauthorization
Act (SARA), is concerned with minimizing
'disposal of household products containing
toxic substances.
In order to identify household products
that may be sources of indoor air pollution
and contribute to disposal problems, this
study reviewed an analytical data base of
1,159 household products compiled by
Midwest Research Institute (MRI) for a
previous study to determine the presence
of common solvents3. The objective of the
original work was to quantify six chlori-
nated target analytes (methylene chloride,
tetrachloroethylene, carbon tetrachloride,
trichloroethylene, 1,1,1 trichloroethane, and
1,1,2-trichIorotrifluorethane) by purge and
trap gas chromatography/mass spectrom-
etry (GC/MS). Full mass spectra were col-
lected at that time and archived for later
• Household Solvent Products: A "Shelf" Survey with
Laboratory Analysis. Washington, DC: U.S. Environ-
mental Protection Agency. EPA-OTS 560/5-87/006,
1987.
«y§> Printed on Recycled Paper
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research. In the present study, computer-
ized reduction of the archival GC/MS data
was the method chosen to best estimate
the concentration of 25 additional target
analytes (See Table 1) in the samples.
Supplementing the earlier work, this study
provides data on the occurrence and esti-
mated concentrations of those 25 addi-
tional chemicals in the household prod-
ucts.
Procedure
In the original study, 1,159 household
products purchased from stores in six cit-
ies (Washington, DC; Denver, CO; Hous-
ton, TX; San Francisco, CA; Chicago, IL;
and Miami, FL) were grouped into 65 prod-
uct categories with each product given a
sample code describing the sample, city
of purchase, product category, product
form, and sequential city/product number.
The samples were analyzed by GC/MS at
three laboratories: MRI, Envirodyne Engi-
neers (St. Louis, MO), and Versar (Spring-
field, VA). The selection of the 25 target
analytes in this study was based on the
Total Exposure Assessment Methodology
(TEAM) studies, analytes recommended
by OPTS, and those cited in other USEPA
programs. Of the 1,159 products, 922 were
analyzed at MRI, 92 at Envirodyne, and
145 at Versar. Only 1,043 of the original
total were available to be analyzed for this
study.
Apparatus
The purge and trap methodology used
in the original study complies with EPA
Method 624, "Purgeables." Although no
actual samples were analyzed by GC/MS
in this study, the same methodology was
used for the analysis of calibration stan-
dards for the 25 additional target analytes.
MRI's MAT CH4-B, one of the GC/MS
systems used in the original study, was
optimized to replicate the chromatographic
behavior observed for the original analy-
ses, and was used to produce calibration
curves for the 25 additional analytes. Ref-
erence standards of target analytes were
obtained from Aldrich Chemical Co. Cali-
bration standard solutions were prepared
fay accurate dilutions of the reference stan-
dards with high purity methanol.
System Calibration for Target
Analytes
In order to obtain response factor infor-
mation for the target analytes, two
quantitation curves were generated ac-
cording to EPA Method 624. Two
quantitation ions were chosen for each
analyte based upon its mass spectrum.
For the low level calibration curve, the
base peak was selected to provide sensi-
tivity to the 0.1% w/w level. For the high
level curve, an ion of lesser abundance
,was chosen so that saturation of the ion
signal was not a factor at the highest
concentration level. The estimated analyte
concentrations were determined by com-
paring the electronically integrated analyte
ion abundances of the quantitation ions
with the internal standard integrated ion
abundances, using response factors de-
termined from the analysis of the calibra-
tion standards.
GC/MS Data Processing
A Finnigan/INCOS data system was
used for data acquisition and handling for
both the analysis of the standards for the
25 new target analytes as well as repro-
cessing, of the original GC/MS. data files.
Analysts used Finnigan's Target Com-
pound Analysis (TCA) software to identify
the target analytes based upon relative
retention times and to compare the ob-
served mass spectrum with an authentic
spectrum obtained by the analysis of a
standard solution. Each identification made
by the TCA software was verified manu-
ally and edited, if necessary, to produce a
completed quantitation report for each
household product. Completed quantitation
reports were transferred as ASCII text to
a Macintosh II computer and archived on
floppy disks. The ASCII quantitation re-
ports were imported into a 4th Dimension
custom designed data base, where they
were reviewed, listed, modified, searched,
and sorted using the software. After the
concentrations of each of the 25 analytes
were computed, that information was
merged with the original data base con-
taining the analytical information for the
original six analytes.
Results and Discussion
Calibration System
The precision of the response factors
for both the low and high level calibration
curves for the 25 target analytes was less
than 35%, which meets the EPA Method
624 calibration criterion. As the calibration
was used to estimate the analyte concen-
trations obtained from several different in-
struments and laboratories, this limit was
deemed acceptable. It was assumed that
the relative responses of the target
analytes obtained during the calibration
were representative of the responses ob-
tained during the original analyses.
Accuracy
For GG/MS analyses, accuracy is nor-
mally determined by the analysis of per-
formance audit or calibration check
samples which have been fortified with
the known levels of the target analyte.
However, no calibration standards were
analyzed for the 25 analytes at the time of
the original GC/MS analyses. Further,
28.5% of the samples were analyzed on
instruments other than MRI's CH-4B, and
the GC/MS data were acquired more than
2 years before the calibration curves for
the new target analytes were generated.
As a result, no direct measure of the ac-
curacy of the concentration values for the
new target analytes is available. To esti-
mate the accuracy of the data for the
additional analytes, the response factors
for the original six chlorocarbons across
the five GC/MS systems were compared.
Based on that comparison, it is estimated
that, in the worst case, a reported con-
centration., value for, one of the 25. addi-
tional analytes may be in error by a factor
in the range of 0.2 to 5.
In estimating the accuracy of the re-
sults for the additional analytes, three fac-
tors were considered. First, the method
readily distinguishes the presence of^an
analyte at relatively high concentrations
from an analyte present at trace levels.
However, concentrations near the lower
reporting limit of 0.1% could have been
omitted incorrectly from the data base.
Second, since over 70% of the samples
were originally analyzed on MRI's CH-4B,
which was used to obtain the calibration
data for the 25 additional analytes, the
reported concentrations are probably more
accurate than the estimate based upon
the variation of calibration between instru-
ments. Third, the relative differences be-
tween concentrations reported for each
set of data from a single instrument are
approximately correct. Thus, even if there
were a five-fold error in a subset of data,
samples could be ranked from highest to
lowest concentration.
Precision
Precision was determined by the re-
peated analysis of one of the standard
solutions by the purge and trap method.
Twenty-one of the target analytes met the
25% range percent criterion recommended
in EPA Method 624".
Occurrence of Target Analytes
The chemicals found most frequently in
the household products were acetone (315
products), 2-butanone (200 products),
methylcyclohexane (150 products), tolu-
ene (488 products), ethylbenzene (157
products), m-xylene (101 products), and
o,p-xy!ene (93 products). A total of 63.6%
of the household products analyzed con-
tained one or more of the analytes at
concentrations of at least 0.1% by weight.
Five analytes, 1,1,2,2-tetrachloroethane,
b Guidelines establishing test procedures for the analy-
sis of pollutants: Method 624-Purgeables (40 CFR
136, Appendix A, pp. 432-446), 1988.
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chlorobenzene, styrene, nonane, and d-
limonene, were not found in any of the
products at or greater than 0.1% by weight.
The complete analytical results for the
determination of the concentrations of the
25 target analytes in the household prod-
ucts are presented in the appendices to
the full report. Appendix A lists the house-
hold products, including the manufacturer
or distributor; the physical form (i.e., liq-
uid, aerosol, paste, etc.); the package type,
size, and lot number if available. Appen-
dix B includes the estimated concentra-
tion (weight percent) of each analyte in
each product. Tables for each analyte
showing products containing that analyte
at levels greater than approximately 0.1%
are in Appendix C, along with a table
listing those 377 household products in
which none of the analytes were observed
above 0.1%.
Conclusions and
Recommendations
An archived collection of GC/MS data
was reanalyzed for!the presence of 25
common volatile chemicals in over 1,000
household products. The reanalysis pro-
vided the concentration and frequency of
occurrence for each chemical in each of
65 product categories. The newly gener-
ated information was Integrated into a com-
puterized data base and configured Jor
ready access by researchers.
The major accomplishment of this work
is the compilation of analytical information
for 25 common chernicals found in over
1,000 household products and integration
of that information with the analytical in-
formation for the original six analytes. The
data base described;in this report is avail-
able from USEPA on diskette in a spread-
sheet format.
The data base will be useful in future
research efforts to assess exposure to
these chemicals in the home environment.
It should allow exposure assessment re-
searchers to: conduct studies on the de-
termination of household sources of spe-
cific chemicals; assess the potential of
specific products to generate harmful va-
pors; and, character of the major chemical
components. of the, household product.
Further, based on the success of this
study, it is feasible that the archived GC/
MS data can be revisited to characterize
the remainder of the volatile chemicals
present in the household products.
The information in this document has
been funded wholly or in part by the United
States Environmental Protection Agency
under Contract No. 68-DO-0137 to Mid-
west Research Institute. It has been sub-
jected to the Agency's peer and
administative review, and it has been ap-
proved for publication.
Mention of trade names or commercial
products does not constitute endorsement
or recommendation for use.
Table 1. Indoor Air Pollutant Chemicals Used in the Household Product Survey
Analyte
Formula
CAS registry number
Acetone
Benzene
2-Butanone
Chlorobenzene
Chloroform
Cyclohexane
1 ,2-Dichloroethane
1 ,4-Dioxane
Ethylbenzene
/7-Hexane
Limonene
Methylcyclohexane
Methylcyclopentane
Methyl isobutyl ketone
n-Nonane
/?-Octane
a-Pinene
Propylene oxide
Styrene
1 ,1 ,2,2-Tetrachloroethane
Tetrahydrofuran
Toluene
m-Xylene
o-Xylene1
p-Xylene(
C3Hp
C6H6
C4H8O
C6H5CI
CHCI3
C6H,2
C2H4CI2
C4HeO2
C8H,0
C6H14
C,0H1SO
C7H,4
C6H12
C6H,2O
C9H20
C8H18
C10H16
C2H40
C8H8
C2H2CI4
C4H8O
C7H8
C8H,0
C8H10
C8H10
67-64-1
71-43-2
78-93-3
108-90-7
67-66-3
1 10-82-7
107-06-2
123-91-1
100-41-4
110-54-3
5989-27-5
108-87-2
96-37-7.
108-10-1
111-84-2
111-65-9
7785-70-8
75-56-9
100-42-5
79-34-5
109-99-9
108-88-3
108-38-3
95-47-6
106-42-3
1 o- and p-Xylene coelute under the analytical conditions originally used 'and are
treated as one analyte.
•&U.S. GOVERNMENT PRINTING OFFICE: 1992 - 648-0X0/40226
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T.M. Sack and D.H. Steele are with Midwest Research Institute, Kansas City, MO 64110
Joseph Behar is the EPA Project Officer (see below).
The complete report, entitled " Indoor Air Pollutants From Household Product Sources,"
(Order No. PB92-136837/AS; Cost: $26.00, 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:
Environmental Monitoring Systems Laboratory
U.S. Environmental Protection Agency
Las Vegas, NV 89193-3478
United States
Environmental Protection
Agency
Center for Environmental
Research Information
Cincinnati, OH 45268
BULK RATE
POSTAGE & FEES PAID
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PERMIT No. G-35
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Penalty for Private Use $300
EPA/600/S4-91/025
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