Ecological Research Series
WATER SOFTENING AND CONDITIONING
EQUIPMENT: A Potential
Source of Water
Contamination
Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Gulf Breeze, Florida 32561
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
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The nine series are:
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This report has been assigned to the ECOLOGICAL RESEARCH series. This series
describes research on the effects of pollution on humans, plant and animal spe-
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This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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WATER-SOFTENING AND CONDITIONING EQUIPMENT:
A Potential Source of Water Contamination
by
Allan M. Crane and Anne E. Freeman
Bears Bluff Field Station
Environmental Research Laboratory - Gulf Breeze
Wadmalaw Island, S. C. 29487
EPA-600/3-77-107
Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Gulf Breeze, Florida 32561
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DISCLAIMER
This report has been reviewed by the Environmental Research Laboratory,
Gulf Breeze, U.S. Environmental Protection Agency, and approved for publica-
tion. Mention of trade names or commercial products does not constitute en-
dorsement or recommendation for use.
ii
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FOREWORD
The protection of our estuarine and coastal areas from damage caused by
toxic organic pollutants requires that regulations restricting the introduc-
tion of these compounds into the environment be formulated on a sound
scientific basis. Accurate information describing dose-response relationships
for organisms and ecosystems under varying conditions is required. The
Environmental Research Laboratory, Gulf Breeze, contributes to this informa-
tion through research programs aimed at determining:
0 the effects of toxic organic pollutants on individual species and
communities of organisms;
the effects of toxic organics on ecosystem processes and components;
0 the significance of chemical carcinogens in the estuarine and marine
environments.
An integral part of these endeavors is the chemical analysis of the
pollutants being studied. Assurance that these analyses are quantitatively
and qualitatively valid depends in part on the elimination of interferences
from extraneous chemicals. One such source of contamination is addressed by
this paper.
Thomas W. Duke
Director
Environmental Research Laboratory
111
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ABSTRACT
Chloroform, trichloroethene,and tetrachloroethene as well as two uniden-
tified compounds were adsorbed from contaminated ground water onto anion-cation
exchange resins during their regeneration and cleaning at the distributing
plant. Contaminants leached into water passed through the resins after dis-
tribution resulted in contamination of deionized water supplies of users.
Concentrations of chloroform and trichloroethene, greater in filtered water
than concentrations observed in contaminated ground water, indicate the
ability of resins to concentrate these compounds. Regeneration and cleaning
of contaminated resins by commercial procedures with clean water is ineffec-
tive. Contaminated resins, which leached 60 yg/1 of chloroform into water,
leached 47 yg/1 after being returned to the distributor and regenerated with
clean water. Increased awareness by users of the limits of ion exchange
resins together with stricter water quality control of distributors is indi-
cated.
This report covers a period from September 28, 1976, to January 27, 1977,
and work was completed as of March 1977.
IV
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CONTENTS
Foreword iii
Abstract iv
Figures vi
Tables vi
Acknowledgements vii
1. Introduction 1
2. Conclusions 2
3. Experimental 3
4. Results and Discussion 6
References 8
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FIGURES
Number Page
1 Typical Gas Chromatogram of Pentane Extract from Water Passed
through Contaminated Ion Exchange/Carbon Filters 5
TABLES
Number Page
Distribution and Concentration of Chloroform, Trichloro-
ethene, and Tetrachloroethene Contamination
Variation in Contaminant Concentration Over Sampling Period
9-29-76 to 1-2-77
VI
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ACKNOWLEDGEMENTS
We thank Dr. Dan Knapp of the Pharmacology Department, Medical University
of South Carolina for initial GC-mass spectrometry and Mr. E. William Loy,
EPA, Region IV, Surveillance and Analysis Division for mass spectral confir-
mations .
vn
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SECTION 1
INTRODUCTION
Medical, biological, and analytical laboratories routinely use water for
the preparation of reagents, dilutions, bioassays, and analytical procedures
as well as for rinsing of glassware. Water free from undesirable contaminants
is therefore an absolute necessity; thus, much effort is expended assuring
that an abundant supply of pure water is available.
In many cases, however, this effort begins and ends with the installation
of ion exchange resin filters. Where resins have undergone strict quality
control, such as imposed by the manufacturer, the use of demineralizers is
sufficient to meet many general laboratory needs. Large units of ion exchange
resins that require maintenance or regeneration by distributors, however, are
no longer subject to this control and have the potential of becoming a source
of contamination. Further, the problems associated with the mistaken but
common assumption that deionized water is a substitute for distilled or ex-
tracted water become compounded where water free of organics is needed. Ion
exchange resins as a source of contamination is exemplified by the following
case study.
Ion exchange resin and carbon filters distributed to industry, research
laboratories, and private homes for water softening and conditioning purposes
were contaminating the water they serviced with volatile chlorinated organics.
Ground water contaminated by an unknown source with chloroform, trichloro-
ethene, tetrachloroethene, and two yet unidentified compounds was used by the
water conditioning company for the processes involved in cleaning and regen-
erating the filters, resulting in their contamination prior to distribution to
customers.
Efforts to determine the extent as well as the source of the ground^water
contamination were undertaken by the Department of Health and Environmental
Control of South Carolina.
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SECTION 2
CONCLUSIONS
Adsorption of contaminants from polluted waters by ion exchange resins
dictates that their quality or freedom from contamination is only as good as
the water used to regenerate and clean them.
Many reports recognize our increasing dependence on ground-water re-
sources. They also note the growing evidence which indicates that the nation's
ground waters are becoming excessively polluted by various surface and sub-
surface disposal techniques (Robertson et al, 1974; Van der Leeden et al,
1975; Crouch et al, 1976; Dunlap et al, 1976; Miller et al, 1977; Tinlin,
1976; Todd et al, 1976).
The affinity of ion exchange resins for neutral halogenated organics
indicates that once contaminated, standard commercial procedures employed for
the regeneration of exhausted resins are inadequate to insure an uncontami-
nated product. The need for an increased awareness among laboratories of the
limits of ion exchange resins as well as their potential for contamination is
apparent.
Finally, the sources of potential ground-water contamination are addressed
by existing federal and state pollution control programs, but these controls
do not provide comprehensive ground-water protection due to the absence of
effective monitoring and reporting programs (Easton, 1977). Although such
programs would not eliminate the need for improved water quality control among
distributors and users of demineralizers, they would help prevent repetition
of occurrences similar to the one reported here.
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SECTION 3
EXPERIMENTAL
Water samples were collected from the various systems into 100-ml vol-
umetric flasks equipped with teflon-lined screw caps (Table 1). The flasks
were brought to volume and immediately extracted by employing a method similar
to one reported by Henderson et al (1976). A 5-ml aliquot of pesticide grade
pentane (Fisher) was pipetted directly into the flask. The water/pentane
mixture was vigorously shaken for approximately five minutes; a 3.0-pi aliquot
of the organic layer was then removed with a microliter syringe for chroma-
tographic analysis.
Gas chromatograms were obtained with a Hewlett Packard model 5710A
equipped with a 63Ni electron capture detector. A 1.8-meter by 2-mm i.d. glass
column, packed with 12% OV-101 on Anakrom Q 100/120 mesh (Analabs), was
utilized. Analyses were run at an injection port and detector temperature of
100°C. The column was maintained at 55°C with 95:5 argon/methane mixture as
the carrier gas (40 ml/min.).
Chromatographic results of Bears Bluff ground water and Charleston city
water extractions were negative. Water standards were prepared from standard
solutions of the three compounds of interest in ethanol. The average recov-
ery rate of chloroform was 89%, whereas those of tri- and tetrachloroethene
were 91% and 97%,respectively.
Trichloroethene and tetachloroethene assignments for two of five gas
chromatographic peaks observed (Fig. 1) were obtained at the EPA's Region IV,
Surveillance and Analysis Division laboratory, Athens, Ga., where samples
were analyzed by the Bellar Volatile Organic Analysis Technique (Bellar and
Lichtenberg, 1974), and quantified on a Tracor 210 gas chromatograph. Mass
spectral confirmation was made with a Finnigan 1015.
Chloroform could not be confirmed by mass spectrometry, but g<3fod GC
evidence was obtained for its identification by employing the admixture tech-
nique to an extracted water sample. The resulting chromatograms indicated no
new peaks nor shoulder or irregularities on the chloroform peak. An increase
in peak-height without corresponding increase in peak-width, conveniently
measured at half-height, indicated excellent retention coincidence between
chloroform and the unknown. The presence of chloroform was further confirmed
by GC analysis at the Department of Health and Environmental Control labora-
tory in Columbia, S. C. Quantification was accomplished by direct comparison
of sample peak areas to those of standards of each of the three identified
contaminants.
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TABLE 1. DISTRIBUTION AND CONCENTRATION OF CHLOROFORM, TRICHLOROETHENE, AND TETRACHLOROETHENE CONTAMI-
NATION
Sample Location Date CHC13
Mt. Pleasant water system
Water Conditioning Service tap Mt. Pleasant, S.C. 11-5-76 <0.1
Ground water (9 meter well)
Water Conditioning Service plant Mt. Pleasant, S.C. 11-5-76 1.6
Process water
Water Conditioning Service plant Mt. Pleasant, S.C. 11-5-76 6.0
Filtered water, Med. Univ. of S.C.
*> Infectious Diseases Laboratory Charleston, S.C. 10-6-76 27
Filtered water, Med. Univ. of S.C.
Basic Sciences Building, Rm. 527 Charleston, S.C. 10-6-76 60
Filtered water,
Environmental Analytics Inc. Goose Creek, S.C. 10-6-76 NDb
Filtered water, EPA
Bears Bluff Field Laboratory Wadmalaw, Is., S.C. 10-6-76 29
C2HC13 C2C14
yg/i
<0.1 0.7
2.8 383
12 554
<0.1 1.9
5.9 5.8
ND 3.2
54 6.1
filters in use 6 months
Not detected
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O
0)
•fl
-p
0)
o
O
•H
C
0)
A
+J
A
O
rtf
H
+J
0)
0123456
MIN.
Figure 1. Typical Gas Chromatogram of Pentane Extract from Water Passed
through Contaminated Ion Exchange/Carbon Filters.
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SECTION 4
RESULTS AND DISCUSSION
Having determined that our laboratory ground water was free from contam-
ination, initial experiments indicated that contaminants appeared after the
water was passed through a commercial water treatment system designed to
furnish deionized water rated at 18 megohm-cm. The system was comprised of
one activated carbon, followed by two ion exchange filters which contained a
cation-anion resin mixture.
Follow-up tests on water samples from similar water treatment and condi-
tioning systems serviced by the same company showed the same contaminants in
systems located at diverse and distant points in Charleston County, S. C.
(Table 1). Sampling conducted at the servicing plant revealed the process
water used for back flushing, regeneration, and rinsing of the ionic resins
and activated carbon employed in the filters was obtained from a 9-meter well
contaminated with the same volatile halocarbons. Three of the five observed
contaminants (Fig. 1) were subsequently identified as chloroform, trichloro-
ethene, and tetrachloroethene.
Although the types of contaminants remained constant over four months of
sampling, there was degree of variability but no apparent trends of their
concentrations in the three systems analyzed during this period (Table 2).
TABLE 2. VARIATION IN CONTAMINANT CONCENTRATION OVER SAMPLING PERIOD 9-29-76
TO 1-2-77 .
Sample CHC13 C2HC13 C2C14
yg/i
Ground water
service plant < 0.0-2.8 0.6-2.8 88-383
Process water
service plant 1.5-6 < 0.1-7.8 389-594
Filtered water, EPA
Bears Bluff Field Lab < 0.1-38 < 0.1-83 3.1-61
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Noteworthy was an apparent increase in concentration of
chloroform and trichloroethene within the filters during servic-
ing. While the concentration of these two compounds in the
contaminated ground water never exceeded 3 yg/1 their concentra-
tion markedly increased in filtered ground water. Maxiitmms of
27 yg/1 and 60 yg/1 chloroform were detected in samples obtained
from the Infectious Diseases Laboratory and the Basic Sciences
Building filters (Table 1), respectively, and a high of 38 yg/1
was detected in our laboratory filters (Table 2).
In general, the length of time various water treatment sys-
tems were in use at their respective locations after being
serviced had little effect on the concentration of contaminants
leached into the water supply. For example, filters which had
exhausted their ion exchange capacity after several months of
use continued to contaminate our water at approximately 80% of
their original rate with 18 yg/1 chloroform, 0.1 yg/1 trichlo-
roethene, and 50 yg/1 tetrachloroethene.
The persistence of these chemicals was demonstrated when
filters containing old, but freshly washed and regenerated
resin and carbon, leached 47 yg/1 chloroform into water passed
through this system.
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REFERENCES
Bellar, T. A., and J. J. Lichtenberg. The Determination of Volatile Organic
Compounds at the yg/1 Level in Water by Gas Chromatography. EPA-670/
4-74-009, U. S. Environmental Protection Agency, Cincinnati, Ohio, 1974.
27 pp.
Crouch, R. L., R. D. Eckert,and D. D. Rugg. Monitoring Groundwater Quality:
Economic Framework and Principles. EPA-600/4-76-045, U. S. Environ-
mental Protection Agency, Cincinnati, Ohio, 1976. 97 pp.
Dunlap, W. J., D. C. Shew, D. R. Scalf, R. L. Cosby, and J. M. Robertson.
Isolation and Identification of Organic Contaminants in Ground Water.
In: Identification and Analysis of Organic Pollutants in Water, L. H.
Keith, ed. Ann Arbor Science Publishers Inc., Ann Arbor, Michigan, 1976.
pp. 453-477.
Easton, E. B., ed. Air/Water Pollution Report. _L5_(3) . 1977. pp. 25.
Henderson, J. E., G. R. Peyton, and W. H. Glaze. A Convenient Liquid-Liquid
Extraction Method for the Determination of Halomethanes in Water at the
Parts-Per Billion Level. In: Identification and Analysis of Organic
Pollutants in Water, L. H. Keith, ed. Ann Arbor Science Publishers Inc.,
Ann Arbor, Michigan, 1976. pp. 105-111.
Miller, J. C., P. S. Hackenberry, and F. A. DeLuca. Groundwater Pollution
Problems in the Southeastern United States. EPA-600/3-77-012, U. S.
Environmental Protection Agency. Cincinnati, Ohio, 1977. 361 pp.
Robertson, J. M., C. R. Toussaint, and M. A. Jorque. Organic Compounds Enter-
ing Ground Water from a Landfill. EPA-660/2-74-077, U. S. Environmental
Protection Agency, Cincinnati, Ohio, 1974.
Tinlin, R. M., ed. Monitoring Groundwater Quality: Illustrative Examples.
EPA-600/4-76-036, U. S. Environmental Protection Agency, Cincinnati,
Ohio, 1976. 88 pp.
Todd, D. K., R. M. Tinlin, K. D. Schmidt,and L. G. Everett. Monitoring
Groundwater Qualtiy: Monitoring Methodology. EPA-600/4-76-026, U. S.
Environmental Protection Agency, Cincinnati, Ohio, 1976. 154 pp.
Van der Leeden, F., L. A. Cerrillo,and D. W. Miller. Groundwater Pollution
Problems in the Northwestern United States. EPA-660/3-75-018, U. S.
Environmental Protection Agency, Cincinnati, Ohio, 1975. 361 pp.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/3-77-107
4. TITLE AND SUBTITLE
WATER-SOFTENING AND CONDITIONING EQUIPMENT:
A Potential Source of Water Contamination
5. REPORT DATE
September 1977 issuing date
6. PERFORMING ORGANIZATION CODE
3. RECIPIENT'S ACCESSION-NO.
7. AUTHOR(S)
Allan M. Crane and Anne E. Freeman
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Gulf Breeze Environmental Research Laboratory
Bears Bluff Field Station
Wadmalaw Island, S.C. 29487
10. PROGRAM ELEMENT NO.
lEAfil
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Research Lab. - Gulf Breeze,
Office of Research and Development
U.S. Environmental Protection Agency
Gulf Breeze, Florida 32561
FL
13. TYPE OF RE PORT AND PERIOD COVERED
Final 8/28/76-8/27/77
14. SPONSORING AGENCY CODE
EPA/600/04
15. SUPPLEMENTARY NOTES
chloroform, trichloroethene, and tetrachloroethene as well as two unidentified
compounds were adsorbed from contaminated ground water onto anion-cation exchange
resins during their regeneration and cleaning at the distributing plant. Contaminant
leached into water passed through the resins after distribution resulted in contami-
nation of deionized water supplies of users. Concentrations of chloroform and tri-
chloroethene , greater in filtered water than concentrations observed in contaminated
ground water, indicate the ability of resins to concentrate these compounds. Regenera
tion and cleaning of contaminated resins by commercial procedures with clean water is
ineffective. Contaminated resins, which leached 60 g/1 of chloroform into water
leached 47 g/1 after being returned to the distributor and regenerated with clean
water. Increased awareness by users of the limits of ion exchange resins together
with stricter water quality control of distributors is indicated.
This report covers a period from September 18, 1976, to January 27, 1977 and
work was completed as of March 1977.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
COSATI Field/Group
Ground water
Water conditioning
Ion exchange resins
Deionized water
Chlorinated organics
Water softening and conditioning equipment
Contamination
South Carolina
06/F
3. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report)
Unclassified
21. NO. OF PAGES
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
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