United States
Environmental Protection
Agency
Health Effects
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S1-84-020 Jan 1985
SEPA Project Summary
GC/MS Analysis of Organics in
Drinking Water Concentrates and
Advanced Waste Treatment
Concentrates
Samuel V. Lucas
The major goal of this research was to
characterize organic material concen-
trated from large volumes (1,500 liters
to 15,000 liters) of finished drinking
water (DW) and finished water from
advanced waste treatment (AWT) plants.
Organic compounds were identified
based on glass capillary gas chroma-
tography-mass spectrometry (GC-MS)
analysis of the fractionated concentrate.
The complex organic concentrates were
partitioned into less complex fractions
by liquid-liquid partitioning, methylation
of acidic components, and f ractionation
of neutral species on silica gel. One of
the purposes of this research was to
enable EPA scientists to correlate the
results of the detailed chemical charac-
terization with those from other pro-
grams that test the potential biological
activity (i.e., mutagenicity) of the
concentrates. Fifteen DW concentrates,
sixteen AWT concentrates, and five
concentrate production method blanks
were analyzed.
The cities represented by the DW
samplings were Cincinnati, Miami,
New Orleans, Ottumwa (Iowa),
Philadelphia, and Seattle. Only 20
percent of the organic material in the
DW concentrates for a given sampling
was recovered in analyzed fractions,
and only one half of that material was
chemically suitable for GC-MS
analysis. Most of the unrecovered
organic portion, and the extracted
material not amenable to GC-MS
analysis, appeared to be humic. In the
15 DW concentrates, 1,091 organic
compounds were identified in 2,383
detection instances.
The AWT plants sampled were
located in Escondido, Lake Tahoe,
Orange County, and Pomona,
California; Dallas, Texas; and
Washington, DC, (Blue Plains). Less
humic material was present in the AWT
concentrates; thus, about 50 percent of
the organic material was recovered in
the GC-MS analyzed fractions. In the
16 AWT concentrates, 991 organic
compounds were identified in 2,097
detection instances.
The GC-MS data were surveyed by
computer for 53 compounds with
potential health effects significance.
For DW concentrates, 31 of these
compounds were present in 108
detection instances. For the AWT con-
centrates, 33 compounds were found in
117 detection instances. The DW
concentrates uniformly contained more
and higher concentrations of materials
attributable either to pollution from the
organic chemical industry or consumer
products containing chemicals than
AWT concentrates. This difference was
probably due to the use of granular
activated carbon (GAC) or reverse
osmosis (RO) as a final treatment step
in the AWT plants but not in the DW
treatment plants. All DW samples
contained some indicators of water re-
use (i.e., drugs or metabolites).
Small volume samples (10 to 30
liters) were also analyzed to determine
the effectiveness of the RO and GAC
treatment in retaining organic mole-
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cules. These results, together with some
of the DW concentrate results, indicate
that RO membranes do not effectively
retain apolar organic molecules.
This Project Summary was developed
by EPA's Health Effects Research Lab-
oratory, Research Triangle Park. NC, to
announce key findings of the research
project that is fully documented in a
separate report of the same title (see
Project Report ordering information at
back).
Introduction
Assessing the health effects of trace
(parts per billion, ppb) levels of organic
material in water is an important, if not
determining, factor in establishing
maximum permissible contamination
levels for drinking water (DW) and
finished water from advanced waste
treatment (AWT) plants The issue of
trace-level organic chemical contamina-
tion of DW will continue to be empha-
sized in environmental health effects
research. In the western states, the use of
potable or other high-quality AWT
finished water is certain to assume a
major role Pilot- and production-scale
AWT plants are already providing high-
quality water for use in ground-water
injection—either to prevent sea water
intrusion into coastal aquifers or simply
as aquifer replenishment In addition,
direct potable reuse of AWT finished
water is now being planned for some
municipalities for which unlimited sup-
plies of fresh surface water or ground
water are not presently assured Detec-
tion and control of trace-level organic
contamination in these AWT reuse waters
is obviously important for the ultimate
protection of DW sources
The Toxicology and Microbiology
Division of the Health Effects Research
Laboratory of the U S EPA in Cincinnati,
Ohio (HERL-CI) is pursuing a research
program to characterize the trace-level
organic materials in DW and AWT water
and to test the biological activity of these
materials for their potential health
effects The goal of this research was to
characterize the organic materials in
sufficient detail to enable EPA to
correlate the compound identification
results with the biological test results.
This correlation may suggest which of the
organic compounds or classes of
compounds have sufficient potential
health effect significance to warrant
future regulation and monitoring.
In HERL-CI's approach to this research
problem, large quantities (1,500 to
15,000 liters) of DW and AWT water were
concentrated, principally by reverse
osmosis, to yield gram-quantity amounts
of concentrated organic material. Eighty
percent of each organic concentrate was
reserved for biological testing Half of the
remaining 20 percent was analyzed for
organic compounds by glass capillary gas
chromatography-mass spectrometry
(GC-MS) Thus, the sample aliquot
analyzed represents between 150 and
1,500 liters of the original water for a
theoretical concentration factor of
150,000.1 to 1,500,000 1. This extreme-
ly high concentration, coupled with
fractionation of the sample into five
separately analyzed organic polarity
groups (thereby adding another order of
magnitude to the concentration factor),
allowed for a more detailed characteriza-
tion of the portion of organic material
amenable to GC-MS analysis in these
clean watersthan any previous approach
Theoretical sensitivities of some identified
compounds reached below the 0 1 part
per trillion (ppt) level (0 1 nanogram per
liter)
The following is a brief description of
the analytical scheme employed
• Fractionation of the concentrate into
five different polarity groups
• Glass capillary GC-MS analysis of
four of the fractions on two different
GC phases with all generated data
archived on 9-track magnetic tape
• Residue weight analysis of the un-
partitioned concentrate and the five
fractions
• Attempted identification based on
mass spectra of all chromatographic
peaks and shoulders in the GC-MS
data
• Automated searching of GC-MSdata
filed for 53 high-interest compounds
and quantification of those found
• Confirmation of tentative identifica-
tions by comparison with GC-MS
data generated from commercially
obtained reference compounds
• Entry of compound identification
results and other pertinent
concentrate information into
Battelle's mainframe computer for
automated data management and
generation of tabular listings of
results
• Concentrate analysis report genera-
tion
Conclusions
The results of this research have
shown that the fractionation of complex
organic concentrates followed by glass
capillary GC-MS analysis enables the
identification of hundreds of organic
compounds present in these samples.
Moreover, concentration techniques in
which thousands of liters of water are
used to produce the analyzed sample,
together with computerized GC-MS data
searching, have enabled theoretical
sensitivities toward individual pollutant
species which extend well below the ppt
(nanogram per liter) level.Thus, results of
this research have produced more
detailed chemical characterizations of
very clean drinking waters and advanced
waste treatment finished waters than
previously possible.
The results for drinking water (DW)
provide the following conclusions
• Most of the organic material in the
analyzed concentrates consisted of
humic-related substances which are
not amenabletoGC-MSanalysis On
the average, more than 90 percent of
the organic material present in the
concentrates was not recovered
through the fractionation scheme.
Part of the recovered material is not
suitable for characterization by GC-
MS analysis, and it is estimated that
only 30 to 60 percent of the material
recovered into fractions (i.e., 3 to 6
percent of the original concentrates)
can be characterized by GC-MS
analysis.
• All of the DWsamples(exceptforone
case which served as a blank)
contained many identified organic
compounds, generally between 150
and 400 different species.
• The species identified at the highest
levels and greatest numbers were
non-aromatic and aromatic
carboxylic acids
• All DW concentrates contained some
evidence of the prescence of re-use
water via the identification of drug
metabolites and other materials
expected to originate from domestic
sewage.
• All DW concentrates showed some
evidence for contamination by
organic compounds from industrial
discharges (organic solvents and
chemical industry commodities,
intermediates and wastes), and
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consumer use of organic chemical-
containing products including herbi-
cides and pesticides Concentrates
from Cincinnati, Philadelphia, and
New Orleans contained the highest
levels of these substances
• All DW concentrates contained
halogenated species which probably
originated from the chlormation of
naturally occurring organic material
in the source water This result was
the most pronounced for the Seattle
and Miami concentrates.
• A tentative conclusion that the
reverse osmosis membranes used
for pre-concentration did not
effectively retain (or, perhaps,
absorbed) highly apolar species was
based on a comparison of the reverse
osmosis-produced concentrates
from a Cincinnati sampling with the
concentrate produced by direct XAD-
2 adsorption/elution prepared from
the same volume of identical water
Based on the limited evidence, RO
was more effective for recovering
highly polar, water soluble materials,
especially humic material.
For the AWT concentrate analysis
results, the use of contact with granular
activated carbon (GAC) was obviously
effective in reducing the amount of
organic material recoverable in the final
concentrate. Almost without exception,
the AWT concentrates contained less
organic material in the analyzed fractions
and resulted m fewer identified
compounds and lower detetected levels
than the DW concentrates. For some
of the AWT concentrates, these compara-
tive differences were substantial.
However, the sampled finished AWT
water contained higher total organic
carbon (TOC) levels than the sampled
finished DW, it can therefore be con-
cluded that the finished AWT water
contained higher levels of material not
recoverable by RO or not suitable for GC-
MS analysis than did the finished DW
Assuming that the AWT influent
contained organic material suitable for
GC-MS analysis at levels at least as high
as those for the finished DW, one must
conclude that the GAC contact step in the
AWT process was effective in reducing
the levels of GC-MS analyzable organic
substances to below those for the
sampled DW. Compared to the DW
concentrates, the AWT concentrates
contained higher levels of fatty and other
acids, phthalates, and poly glycol ethers
(relatively polar species) but generally
lower levels of apolar species attributable
to the use or production of industrial
organic chemicals This observation
supports the conclusion about the
effectiveness of GAC contact stages in
the AWT plants Higher efficiency for
removing the apolar species (wiiich are
more suitable for GC-MS analysis) than
the polar, more highly water-soluble
species is consistent with expected
chemical behavior. One AWT plant
(Escondido, California) employed RO
rather than GAC contactor treatment
Since the Escondido concentrate
contained less organic material and
fewer species identifiable by GC-MS, the
tentative conclusion is that RO is highly
effective for final treatment for AWT
systems. However, insufficient data are
available to compare RO effectiveness to
GAC treatment.
Recommendations
Future work in correlating potential
health effects of organic contamination in
DW and AWT water with the nature of the
organic materials present should employ
biological testing of individual chemical
group fractions of the organic concen-
trates rather than bulk concentrates
Such a strategy could greatly reduce the
amount of chemical analysis required
Results from the DW concentrates indi-
cated that more than 80 percent of the
organic material present was humic,
which was not suitable for characteriza-
tion by GC-MS, yet these materials may
be responsible for a significant amount of
biological activity Standard methods are
available for isolatmgthe humic materials
in concentrates Separate biological test-
ing of a humic/fulvic acid fraction as well
as the fractions isolated for GC-MS anal-
ysis would greatly simplify the task of
correlating the organic compounds in the
concentrate with the biological testing
results For example, the polar neutral
fraction always contained a plethora of
alcohols, ketones, diester plasticizers and
mixed functionality species, many of
which are difficult to identify by GC-MS
analysis. Certainly, many of these
compounds are biologically inactive, and
if this polar fraction consistently failed to
show biological activity, GC-MS analysis
could be omitted. The opposite may be
true for the aromatic fraction, which
represented only 0 05 to 1.0 percent of
organic material in the concentrate.
Comparison of analysis results for
concentrates prepared from identical DW
samples by the RO-based method and by
the direct XAD-2 adsorption/elution
met hod suggested that much and possibly
most of the apolar anthropogenic species
in the sampled water were not recovered
by RO. These anthropogenic species are
of the highest interestfor potential health
effects investigation. On the other hand,
direct XAD-2 adsorption/elution did not
recover ionized, highly polar and
macromolecular species such as
humic/fulvic acids and poly glycols so
well as the method employing RO pre-
concentration. Development of a
combination of these two methods could
provide a concentrate more representa-
tive of the organic material present in the
original water, so that more reliable
health effects conclusions could be
drawn
The results represented in this work
constitute the most detailed chemical
characterization of a wide variety of clean
waters such as DW and finished AWT
water from various sources However,
the results also show that only a small
fraction of the organic material recovered
into the concentrate is suitable for char-
acterization by GC-MS methods. Detailed
characterization of the major part of the
organic material which was not suitable
for direct GC-MS analysis should be
performed to complete this work Because
the completion of this work would have
great importance in health effects evalua -
tionsand mtrmsicscientific value, present
work should be continued
In future analyses of this type, the
following minor modifications would be
more cost effective.
• The use of polar capillary GC
columns capable of higher
temperature limits could eliminate
the necessity for analyzing the high
polarity, medium polarity and acid
fractions on the apolar phase
• GC-MS analysis of the aromatic
fraction should be restricted to the
apolar GC column
• Based on the compound identifica-
tion results of this study, additional
compounds could be selected for
computerized data searching These
compounds could be selected to
profile different characteristics of
source waters
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Samuel V Lucas is with Battelle-Columbus Laboratories, Columbus, OH43201.
Frederick C. Kopfler is the EPA Project Officer (see below).
The complete report consists of three volumes, entitled "GC/MS Analysis of
Or games in Drinking Water Concentrates and Advanced Waste Treatment
Concentrates;" fSet Order No. PB 85-128 213; Cost: $61.50)
"Volume 1 Analysis Results for 17 Drinking Water, 16 Advanced Waste
Treatment and3 Process Blank Concentrates," (Order No. PB 85-128-221;
Cost $25 OO)
"Vo'ume2. Computer-Printed Tabulations of Compound Identification Results
for Large-Volume Concentrates," (Order No. PB 85-128 239; Cost: $29.50)
"Volume 3. Batch Liquid-Liquid Extraction and Analysis of 10-Liter Sample
and Analysis of Concentrates from Small Volumes (10 to 5O Liters) of
Drinking Water," (Order No. PB 85-128 247; Cost: $17.50)
The above reports will be available only from: (cost subject to change)
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone. 703-487-4650
The EPA Project Officer can be contacted at:
Health Effects Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park. NC 27711
U S GOVERNMENT PRINTING OFFICE, 1985 — 559-016/7880
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
BULK RATE
POSTAGE & FEES PAI
EPA
PERMIT No G-35
Official Business
Penalty for Private Use $300
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