DETERMINATION AND EVALUATION OF
ENVIRONMENTAL LEVELS OF TRICHLOROETHYLENE
to
ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF COXIC SUBSTANCES
July 29, 1977
Contract No. 68-01-1983
BATTELLE
Columbus Laboratories
505 King Avenue
Columbus, Ohio 43201
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NOTICE
This document is a preliminary draft. It has
not been formally released by EPA and should
not at Lbis stage be construed to represent
Ayency policy. It is being circulated for
comment on its technical accuracy and policy
implications.
ii
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TABLE OF CONTENTS
Page
EXECUTIVE SUMMARY vii
1. INTRODUCTION 1-1
2. OCCURRENCE OF TRCCHLOROETHYLENE IN THE ENVIRONMENT 2-1
Sources of Trichloroethylene in the Environment 2-1
TrLchloroethyJene Production 2-1
Uses of TrichloroeLhylene 2-4
Pathways for Entry of Trichloroethylpne into the
Environment 2-7
Trichloroethylene Levels in the Environment 2-10
Oata from the f.iturature 2-10
Data from the Jiadtelle Monitoring Program 2-18
Discussion of the Data 2-19
3. BEHAVIOR OF TRICHLOROETHYLENE IN THE ENVIRONMENT 3-1
Physical/Chemical Characteristics of Trichloroethylene in
the KnvLronment 3-1
Trans formation of Trichloroethylene in the Environment 3-3
Toxicology of Trichloroethylene and its Possible Degradation
Produces 3-8
4. OCCURRKNCIS OF TRIC11LOROETHYLENE IN FOOD AND OTHER PRODUCTS
THAT COME IN CONTACT WITH MAN 4-1
Food 4-1
Drinking Water 4-1
Other Substances 4-12
5. EXPOSURE AND BIOLOGICAL ACCUMULATION OF TRICHLOROETHYLENE IN MAN. 5-1
Exposure 5-1
Biological Accumulation 5-5
6. ENVIRONMENTAL TRENDS 6-1
7. BIBLIOGRAPHY 7-1
iii
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LIST OF FIGURES
Figure 2.1 Trichloroethylene (TCE) in the Environment. . . 2-2
Figure 2.2 Trichloroethylene Production Processes 2-5
Figure 2.3 Pathways for Entry of TCE into the Environment. 2-9
Figure 2.4 Industrialized Area Where Surface Water Was
Sampled 2-16
Figure 3.1 Reactants and Products of Trichloroethylene and
NO- irradiation 3-5
Figure 3.2 Transformation of Trichloroethylene 3-6
Figure 3.3 Uptake in Relation to Alveol.ir Concentration
After 30 Minutes of Exposure at Rest and
During Exercise 3-9
LIST OF TABLES
Table 2.1 Manufacture of Trichloroethylene ' 2-2
Table 2.2 Trichl oroeLhy Lcue Consumption 2-6
Table 2.3 Physical Properties of Trichloroethylene .... 2-8
Table 2.4 Occurrence of TCE in the Environment 2-]i
Table 2.5 Maximum and Minimum Levels of TCE at Various
Locations in the United States 2-13
Table 2.6 Typical Levels of TCE 2-14
Table 2.7 Miscellaneous Monitoring Data for TCE in the
Atmor.phere 2-15
Table 2.8 Trichloroethylene Concentration in Surface Water
.Samples Taken by the Institute for
Environmental Studies 2-17
IV
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Table 2.9
Table 2.10
TABLE OF CONTENTS
(Continued)
Concentration Ranges for Trichloroethylene in
the Atmosphere Around Producer and User Sites.
Concentration of Trichloroethylene in Water,
Soil, and Sediment in the Vicinity of
Pace
2-20
Table 3.1
Table 3.2
Table 3.3
Table 3.4
Table 3.5
Table 4 L
Table 4.2
Table 4.3
Table 4.4
Table 4.5
Table 4.6
Table 4.7
Table 4.8
Physical/Chemical Properties of Trichloroethylene
Transformation of TCE in the Environment ....
Comparative Toxicity of Trichloroethylene and
Summary of Data on the Carcinogen Lcity of
Toxicity of Trichlorocthy]ene and Its Trans-
Proper ti.es and TCE Concentration of Finished
Water in Five Cities
Some of the Organic Compounds Identified in
Miami, FlorLda- — Finished and Raw Water Samples.
TCE Concentration in Water Sources for Des
Moines, Iowa, Drinking Water and in Controls .
TCE Concentration in Infiltration Gallery and
in Associated Waters .............
TCE Concentrations in North End of Infiltration
Summary of TCE Data for Des Moines Finished
Representative Commercial Products Containing
3-2
3-4
3-11
3-] l\
3-] 5
4-2
4-4
4-5
4-7
4-8
4-10
4-11
Trichloroethylene.
4-13
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LIST OF TABLES (Continued)
Table 5.1 Occupational Exposure 5-2
Table 5.2 Occurrence of Trichloroethylene in Human
Tissue 5-6
Table 5.3 Trichloroethylene Recovered from Tissue . . . 5-7
Table 5.4 Chlorinated Hydrocarbons in Marine Organisms. 5-8
VI
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EXECUTIVE SUMMARY
This report is a determination and evaluation of environmental levels
of trLchloroef.1iy.lene (TCE), based on a review of the literature and other
information sources and on monitoring data obtained to fill gaps in the
published data.
Tr Ichiloroethylene is of environmental concern because of its toxicity
and its widespread use. The major users by far are metal degrcasing and
dry r-leaning, and, chough TCE is incurring disfavor ir these applications,
it may soon find wide application in nonaqucous textile processing and
finishing. The major production of TCE in the U.S. is on the Gulf Coast of
Louisiana and Texns, acid the annual production is about 435 million pounds
(197A figures). It ir. estimated that approximately 60 percent of this is
released into the envirnment each year.
The concentrations of TCE in the atmosphere of the U.S. ranges from
about 1 ppt in remote areas to over .100 ppb in areas near where the substance
is manufactured or used. The concentration drops off rapidly as one moves
away from a source facility.
Surface water concentrations, of TCE range from less than 1 ppb (the
limit of detection) to several hundred ppu in the vicinity of TCE manufacturers.
One measurement as high as; 5 ppm was made in a canal of stagnant water near
a producer site.
TCE concentrations in sediments range from less than 0.04 ppb
to over 100 ppb. Again the high values were found near manufacturers, but
vil
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some of the lowest values were as well.
Soil concentrations of TCE appear to be no higher near
manufacturers than in rural areas, though the data are very limited. The
concentrations are only a few ppb or less.
The behavior of TCE in the environment is controlled by its
structure. TCE is an unsaturated chlorinated hydrocarbon which is not
susceptible to hydrolysis and thus is relatively stable in water and in
the soil. However, the double bond in the compound is susceptible to
attack by free rad Lais and electrophilic reagents and thus is easily
degraded in a photochemical environment such as ambient air. The ultimate
degradation product;.; are simple species commonly found in the environment,
but there arc some intermediates for which little toxicity data exist.
There are very little data on the presence of TCE in food raised
and sold in the U.S. However, data froth the United Kingdom suggest that
TCE Ls found on the ordc-r of parts per billion iti almost all common
foodstuffs. Measurrd concentrations of TCE in U.S. drinking water are less
tlu'iu ] ppb except :in unusual circumstances such as in Des Moines, Iowa.
An unknown source oc TCE contamination has caused levels of TCE as high as
80 ppb to be found in Dee Molnes water.
There is little evidence Lo judge if TCE is accumulating in
living systems. Ljiiiited data on TCE levels in human tissue and in marine
organisms show levels on the order of a few parrs per billion.
The data ace also insufficient to enable trends in the TCE
levels in the environment to be determined.
viii
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1. INTRODUCTION
Trichloroethylene (TCIi) is an important chemical whose health and
ecological effects, environmental behavior, and technologic and economic
aspects arc important to the U.S. Environmental Protection Agency. In a
recent report prepared for the EPA by the Office of Toxic Substances, the
reasons for concern regarding TCE are discussed (U.S. Environmental Pro-
tection Agency, 1976). These include its wide use in the production of
fabricated metals and cleaning fluids which results in extensive worker
exposure; the detection of this compound in ambient air and water, in
food, and in human tissues; and finally its identification by the National
Cancer Inrtitute (NCI) as a carcinogen in laboratory animals.
The purpose of this program has been to determine and evaluate envi-
ronmental levels of trii:hloroethylcne. The approach taken involved four
distinct phases:
1. Review and evaluation of literature and other sources
of previously collected monitoring data
2. Development of an environmental monitoring program for
fill ing selected data gaps
3. Environmental sample collection and analysis
4. Presentation of the above material as an integrated
information data package.
Previously collected monitoring data from the literature and levels of
triclilorocthylene in the environment as determined under this program
will be summarized and evaluated.
1-1
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Levels of a substance in the environment can be reported in various
ways. The level of trichlorocthylene in air will be reported in two ways --
as ppb (volume/volume) and in ug/mr. Either both values will be given or
a conversion factor will be indicated. For all other media -- water, soil,
and sediment -- the data will be given as ppb (weight/weight). Various
conversion factors can be found in Table 2.3.
There are several important reviews on the subject of trichloro-
ethylene: Specifically, a preliminary study of selected potential environ-
mental contaminants including trichloroethylcne (U.S. Environmental Protec-
tion Agency, 1975), a preliminary economic impact assessment of possible
vegulatory action to control atmospheric emissions of selected halocarbons
(Shamel et al., 1975), an .impact overview and an abstracted literature collection
on trichloroethylene (Waters el al., 1976), an air pollution assessment of tri-
chloroethylene (FulJer, 1976), a criteria foe a recommended standard for
occupational exposure to t.i Ichloroethylcnrie (National Institute for Occu-
pational Safety and Health, 1973), a proposed occupational exposure
standard for trichloroethylcne (Department of Labor, 1975), a toxicology
study called "Methylchloroform and Trichloroethylene in the Environment"
(Aviado et al., 1976). These references have been consulted (in addition to
many original journal articles and various reports) in preparing this
document.
1-2
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2 . OCCURRENCE OF TRICI1LOROETIIYLENE TN THE ENVIRONMENT
SOURCES OF TRrCllLOROETIlYLENE IN THE ENVIRONMENT
In Figure 2.J, the presence of trich]oroethylene in the environment and
the flow from production to use to human exposure is diagrammed. Some of the
information to he presented Ls summarized in this figure. Trichloroethylene
is a synthetic material created by man in huge amounts. The ultimate sources
are the production facilities, and the amount produced largely determines how
much tricnloroethylene might eventually find its way into the environment.
TrichloroetliyJene Product Ion
The evidence is that all trichloroethylene that appears in the environ-
ment is produced by man. The estimated world production capacity for tri-
•3
chloroethylene is 3,010 x JO" tons/year (1973) (McConnell et al., 1975).
U.S. production of trJchloroethylene was 435,000 x 10 pounds in 1974
(Chemical and Engineering News, May 19, 1975). Of the total, world produc-
3
tion, it is estimated that approximately 600 x 10 tons of trichloroethylene
arc released to the atmosphere and 10,000 tons to the ocean each year.
The production sites, annual capacity, and raw material for the manu-
facture of trirhloroethylcne arc given in Table 2.1. As is obvious from the
table, the bulk of trichloroethylene is produced on the Gulf coast of
Louisiana and Texas.
2-1
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to
I
•2 26 x 10 Ib - i-orld
• 0 135 x .09 - U s 1973
.1' 5 !>pb
0 37 p,!1! (lousier, Toxrs)
Sc.i aco- 0 1 te 1 9 pub
rBa. ., i Pl,b
BoJv Fa: 1 to 10 pih
B 1 to 100 ??b
"j-nal-, 1 to 10 D,-l
1 Lo 10 ,ipb
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TABLE 2.1 MANUFACTURE OF TRICHLOROETHYLENE
Company and Location
Annual Capacity as
of September 1972,
millJons of pounds
Raw Material
Dow Chemical. U.S.A.a
Freeport, Texas
Diamond Shamrock Chemical Co.
Electric Chemicals DLv.
Deer Park, Texas
Ethyl Corporation
Industrial Chemicals Div.
Baton Rouge, Louisiana
Hooker Chemical Corporation0-
Industridi Chemicals Div.
Tacoma, Washington
Taft, Louisiana
PPG Industries, Inc.d
Industrial Chemicals Div.
Lake Charles, Louisiana
Total
150
60
50
30
40
200
530
Source:
a
U.S. Environmental Protection Agency, 1975.
Ethylene
Ethylene
Ethylene
Acetylene
Acetylene
Ethylene
An additionaJ 50 million pounds per year unit was closed in late 1971.
An 18--iuorith modernization beginning Jn 1977 is planned. New project
will result: in improved technology to reduce hy-products and increase
efficiency in use of raw material chlorine. Expected capacity of
refurbished unit will be 120 million pounds per year.
"Believed to be producing only small quantities (production was not
reported to the U.S. Tariff Commission in 1971 or in the first 6 months
of 1972). Capacity of the plant will be expanded by April, 1973.
cA 60-million-pounds-per-year acetylene-based TCE plant at Niagara Falls,
New York, was closed in early 1972.
^Expanding to 280 million pounds per year by the end of 1973.
2-3
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Based on the reactions involved in the production of trichloroethylenc
(Figure 2.2), several other chlorinated hydrocarbons might also be expected
to reach the environment. Thus, at the trichloroethylene plants, Ln addition
to trichloroethylene, tetrachloroethane, hexachlorobutadicno, and dichloro-
ethane might be detected. At all sites, chlorine and hydrogen chloride arc
important inorganics that are generated and consumed in these processes.
Uses of Trichloroethylone
Table 2.2 gives some indication of the major uses to which trichloro-
cthylene was put in 1971. By far, the major use of this solvent was in metal
degreasing and dry cleaning. Trichloroethylene has, in the past, been the
solvent of choice in vapor degreasing; but because of its lower toxicity and
less severe pollution problem, methylchloroform is replacing trichloroethylenc
in many places. While trichloroethylonc has incurred disfavor in these
applications, it may soon find wide application in nonaqueous textile proc-
essing and finishing.
Trichloroethylene has also been used as an anesthetic and many hospital
personnel arc routinely exposed to tricliloroethylene (Lloyd et al, 1975).
Some of the other industries that are using tricliloroethylene on a
large scale are the following: food products, textile mill products, paper
produces, printing trades, chemical manufacturing, rubber and plastics manu-
facturing, stone and clay products, primary steel manufacturing, metal
fabrication, machinery manufacturing, electrical equipment, transportation
equipment, communication, wholesale trade, business services, auto repair,
and mechanical, services. Each of these industries is estimated to have over
1,000 people exposed to Lrichloroethylene (Lloyd et al., 1975).
2-4
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From Kthylene Through Ethylene Dichloride (90% of Total Product-ion)
C1CH2CH2C1
8C1CU2CH2C.L
+ 4
]?ron Acetylene (10% of Total Production)
1IC H CH + 2C1 -v Cl CHCUC1
C10CHCHC1., — -rT-r--r~> C1CH = cclo + HCL
2 2 or Catalyst 2
Fjgure 2.2 Trichloroethylene Production Processes
2-5
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TABLE 2.2 TRICHLOROETHYLENE CONSUMPTION, 197]
Mi 11 Jons of Pounds Percent
Met. i.l cleaning
Exports
Miscc] Inneous
Total
'i!>5
52
32
539
84
]0
6
]00
Source: U.S. Environmental Protection Agency, 1975
2-G
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Pathways for Entry of TrLchlorocthylenc into the Environment
The pathways for entry of trichloroethylene into the environment are
determined primarily by the physical properties and to a lesser degree by the
chemical properties of the compound.
Trichloroethylene (TCE) is a colorless, nonflammable, volatile Id quid,
which boLLs at 87 C at atmospheric pressure. Tt has appreciable vapor
pressure—58 mm Hg at 20 C—and limited, though not insignificant, solubility
in water—0.11 g trichloroethylene in 100 g H20 at 25 C. This 'compound is
thermally stable, is sensitive to oxidation, but is resistant to hydrolysis.
These and other properties are summarized in Table 2.3.
TrichLoroethylene Lb manufactured on a large scale—about 435 million
pounds in 1974 in Lhc U.S. Trichloroethylene is used primarily as a cleaning
solvent: either in vapor decreasing or in cold cleaning. It is estimated
that approximately 60 percent of the trichloroethylene produced is released
into the environment each year.
These facts lead Io the conclusion Lhat trichloroethylene is released
into the air In relatively large amounts. There is some evidence that
trichloroethylene is rapidly degraded and has a relatively short half-life
in the atmosphere. However, the fate of trichloroethylene in air is not
clearly understood, and its fate in water is even less well understood.
All of these related facts arc combined into a picture depicting the
pathways for entry of trichloroethylene into the environment in Figure 2.3.
The heavier the line, the more important is the pathway. Thus, Eor
trichloroethylcue, the most important pathway for entry into the environment
is release of this substance by users into the air, followed by release into
2-7
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TABLE 2.3 PHYSICAL PROPERTIES OF TR1C11LOROETHYLENE
Structural formula:
CIN
H
oc
C HC1 o
C, 18.128 percent;
cr CL
Molecular formula:
Analysis:
Molecular weight: 131.29
Appearance: Colorless liquid
Boiling point: 86.7 C
Melting point: -87.1 C
Decomposition temperature: 700 C
Flash point: None
Autoignition temperature: 410 C
Specific gravity (20 C/4 C): 1.465
Vapor density at 25 C: 4.53 g/£
Surface tension at 20 C: 29 dyne/cm
Odor threshold: Aproximately 20 ppm
Viscosity at 20 C: 0.58 centipoise
Refractive index at
Dielectric constant
Vapor pressure: _^C
0
20
40
Solubility in water
H, 0.77 percent; Cl, 80.95 percent
20 C: 1
(liquic1)
°C
25
60
.4773
at 16
inm Hg
20.1
57.8
146.8
3.42
Solubility of water in TCK:
.
25
60
Distribution coefficient of solubility:
Water/air
Blood/air
Plasma/air
Fat/water
Conversion factors: Air (25 C):
/IQOg water
0.] 1
0.125
g/lOOg TCE
0.033"
080
20
0.
C
37 C
Water (20 C)
Other media:
3 .1.6
18-22 8-10
16-20
34.4
1 ppb (vol/vol) = 5.27 ug/m
1 ug/1 = 186.2 ppb (vol/vol)
1 ppb (vol/vol) = 1.465 ppb (vol/vol)
1 ppb (wt/wt) = 1 yg/]
1 ppb (wt/wt) = 1 ytg/kg
2-8
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TERRESTRIAL ECOSYSTEMS
mmrnmiDisTn LBUTIO
BY-PRODUCTS
VASCULAR !
INVERTEBRATES
SEDIMENTS
AQUATIC ECOSYSTEMS
Figure 2.3 Pathways for entry of trichloroethylene into the environment.
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the air by manufacturers, followed by release into water by manufacturers and
users, followed by absorption in soil, collection in sediment, and then all
of the other Interactions shown in the figure. The environmental media would
thus be ranked as follows in order of decreasing trichloroethylene concen-
tration: air, water, soil, sediment, and biota.
TRICHLOROF/L'llYUiNE LEVELS IN THE ENVIRONMENT
Data From the Literature
No extensive monitoring programs designed specifically for
trichloroethylene have been identified. The concentration of trichloro-
ethylene in various parrs of the environment has been estimated, Table 2.^.
In addition, trichloroethylene has been quantified in air and surface, water
at various sites and these data cire presented in the following sections.
However, there arc serious gaps in these data. There are no data
available in the literature on production 5iil.es or on sites or cities? where
there is known to be extensive use of trichloroethylene. New information on
such sites is reported in the section on "Dnta From the Battelle Monitoring
Program". In addition, time studies could be very informative. For example,
how does the trichloroethylene concentration vary from hour to hour, from
day to day, and from season to season? Is washout important? Is the amount
of sunshine critical to the degradation of trichioroethylene or is degradation
relatively constant? These and similar questions might be answered if a
single site were sampled over an extended period of time. No such study has
yet been undertaken.
2-10
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TABLE 2.4 OCCURRENCE OF TRTCHLOROETHYLENE
IN THE ENVIRONMENT
Typical Concentrations
Air
Radn v/ater
Surface wafer
Potable water
Sea v-/ater
Marine sediments
Marine invertebrates
Fish
Watcrbirds
Marine maunio-7
>io-B
io"8
io-9
—9
10
n
10
Source: McConnel] et al., 1975.
2-11
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TTich]oroethy]enK in the Atmosphere
TrLchloroethylcne has been determined along with other halocarboris at
various locations throughout the U.S. and around the world. The most ex-
tensive data are reproduced in Tables 2.5 and 2.6. These data are taken from
a study done at Cook College, Rutgers University (Lillian et al., 1975).
Other data nre summarized Ln Table 2.7.
Trichloroethy.1c.ne in Surface Waters
In 3975, a program entitled "Monitoring to Detect Previously
Unrecognized Pollutants" began at the University of Illinois at Urbana-
Champaign. This program is administered within the Institute for Environ-
mental Studies under a contract with the U.S. Environmental Protection Agency.
The coprincipal investigators are Professor E.S.K. Chian, Department of Civil
Engineering, and Professor B. S. Ewing, Director of the Institute for
Environmental Studies.
The objective oJ: the program is to direct previously unrecognized
pollutants in surface waters. Approximately 200 x^ater samples are being
collected from 14 heavily industrialized river basins. These areas and
the approximate number oE samples to be taken at each location are indicated
in Figure 2.4 (Chian and Ewing, 1976. Progress Report No. 4). The results
are summarized in Table 2.8. For some of the samples, values for
trLchloroethyleiie were not reported. When the presence of a substance was
not reported, ii: is not clear whether the substance was not present, was
not quantified, or wos not detected for some reason such as interference
by another compound. However, trirhloroethy.lene was detected in 142 of
2-12
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TABLE 2.5 MAXIMUM AND MINIMUM LEVELS OF TRICHLOROETHYLENE
IN THE ATMOSPHEKF, AT VARIOUS LOCATIONS F.N THE
UNLTEU STATES
Monitoring Period
and Location
LevcJ s
Concentration,
ppb
June 18-L9, J974
Seagirt, N.J.
(National Guard Base)
June 27-28. 1974
New York, N.Y.
(45th & Lexington)
July 2-5, .1974
Sandy Hook, N.J.
(Fort Hancock)
July 8-.10, 1974
Delaware City, Delaware
(Road 448 f> Route 72
intersection)
JuJy L1-.I2, J974
Baltimore, MD.
(170J Poncabircl Pass,
Ford Ho "Labi rd area)
July 16-26, 1974
Wilmington, OH
(Clinton County Air
Force Base)
Max.
Min.
Mean
Max.
Min.
Mean
Max.
Min.
Mean
Max.
Min.
Mean
Max.
Min.
Mean
Max.
Min.
Mean
2.8
<0.05
0.26
1.1
0.1]
0.71
0.80
<0.05
0.34
0.56
<0.05
0.35
<0.05
<0.05
0.63
<0.05
0.19
September 16-19, .1974
Wlri.tr Face Mountains
(New York State)
March-December, 1973
Bayonne, N.J.
Max.
Min.
Mean
Max.
Min.
Mean
0.35
<0.05
0.10
8.8
<0.05
0.92
Source: Li.IJ.ian et al., 1975.
2-13
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TABLE 2.6 TYPTCAL LEVELS OF TRICHLOROETHYLENE
IN THE ATMOSPHERE
Date and TUTK-:
Location
Concentration, ppb
June 27, 1974
2300
New York, N.Y.
0.11
September 17, 1974
]200
July 2, L974
1400
July 19, 1974
1300
JuLy 17, ]974
1228
July 17, 1974
1203
White Face Mountains <0.02
N.Y. State (noiiurban)
Over Ocean 0.18
Sandy Hook, N.J.
4.8 km (3 m:i.) offshore
Seagirt, N.J. <0.02
(National Guard Base)
Above tin; Inversion <0.02
elevation 1500 m (5000 ft.)
Wilmington, Ohio
InversJon Layer 0.075
elevation 450 m (1500 ft.)
Wilmington, Ohio
Source: Lillian el al., 1975.
2-14
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TABLE 2.7. MISCELLANEOUS MONITORING DATA FOR TRICHLOROETHYLENE IN THE ATMOSPHERE
Ni
I
Location
Date of. Data
Collection
Concentration
Method
3
Reference
New Brunswick NJ
ii ii
Kansas City-NASN
Station
Houston TX and
vicinity
Los Angeles Basin
Worldwide
Pullman WA
1973
Unreported
1974
Nov. 1974
April 1975
1974
Dec. 1974 to
Detected
0.75 ppb
Detected
ii
"
5 ppb
<5 ppt
Coulometric GC
ii ii
GC/MS
GC/MS computer
ii ii
Estimate
GC/MS
Lillian and Singh, 1974
ii ii
Bunn et al. , 1975
Pellizzari et al., 1976
1! II
Goldberg, 1975
Grimsrud and Rasmus sen,
1975
Western Ireland
North Atlantic
Northern Hemisphere
Southern Hemisphere
Liverpool, England
Rural areas of
Britain
Over the northeast
Atlantic
Britain, perimeter
of a manufactur-
ing plant
Heath, near the
above plant
Suburban area, re-
moved from plant
Tokyo
Feb. 1975
June/July 1974
Oct. 1973
1974
1974
March 1972
1972
Aug. 1972
1972-1974
May 1974-
April 1975
15 ppt
<5 ppt
15 ppt
1.5 ppt
850 ng/m3 (^160 ppt)
11 ng/n3 (average)
6 ng/m3
40-64 ppb (mass)
12-42 ppb (mass)
1-20 ppb (mass)
1.2 ppb (annual
average_
Coulometric GC
ii M
EC/GC
n
ii
Lovelock, 1974
Cox et al., 1976
11 M
Murray and Riley, 1973
Pearson and McConnell, 1975
-------
h-1
Encircled numbers indicate quantity of
samples to be collected in each area.
Figure 2.4. Industrialized area where surface water
was sampled (Source: Chian and Swing, 1976),
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TABLE 2.8. TRIC11LOROETHYLENE CONCENTRATION IN SURFACE WATER SAMPLES
TAKEN BY THE INSTITUTE FOR ENVIRONMENTAL STUDIES
Area
Type of Water Analyzed
Chicago, Illinois
Illinois
Pennsylvania
New York City area
Hudson River area
Upper and Mi.dd.le
Mississippi RLver
Lower Mississippi
River
Houston area
Alabama
Ohio River Basin
Great Lakes
Tennessee River Basin
u
Lake Michigan, sewage 9
treatment plant effluent,
filtration plant, chan-
nels
II]inois River 11
Delaware, Schuylkill, 25
and Lehigh Rivprs
Hudson River and bays 16
Hudson River 12
Mississippi River 19
Mississippi River 9
Calveston Bay and 8
channels
Black Warrier, Tornbigee, 7
Alabama, and Mobile Rivers
Ohio River and tributaries 10
Lake Superior, Michigan, 13
Huron, Ontario, Erie, and
vicinity
Tennessee River and 1
tributaries
Concentration.
Number of Range (Average),
Samples ppb
9 0.5 to 10(5)
<1 to 7 (<2)
<1 to 18 (-2)
<1 to 7 (<3)
<1 to 4 (
-------
the over 200 samples analyzed and the concentrations range: Erom <1 ppb to
188 ppb in the surface waters sampled. This information has all been taken
from the first five progress reports from the Institute for Environmental
Studies on KPA Contract 68-01-3232 (Chian and Ewing, 1976).
Many other organics have been identified and quantified and elemental
inorganic analyses were done during this program. From this information and
details of the methodology used, the reader is referred to the original
reports.
Pearson and McConnel] (1975) report concentrations of 0.15 ppb
trichlorocthylcne in rainwater collected in Runcorn, England. The highest
concentrations that these researchers measured in upland river waters was
6 ppb. These same authors also reported that they have rever detected
organochloiines in well waters. With a normal detection limit of 0.01 ppb,
Pearson and McConnell (1975), between April, 1973 and August, 1973, determined
that: the average concentration of trichloroethylene in Liverpool Bay sea
water was 0.3 ppb with the maximum concentration of 3.6 ppb found. Tn
Liverpool Bay sediments a maximum trichloroethy]ene concentration of 9.9 ppb
was found.
There have been several studies on the presence of trichloroethylene
and other liaHocarbons in drinking water and raw water samples. This
information is presented in the section on "Drinking Water".
Data From the Battelle Monitoring Program
A program to determine environmental levels of trichloroethyiene was
initiated :in 1976 at the Tlattelle Columbus Laboratories. Rased on a review
of the literature, it was decided that determinations of trichloroethylene
2-18
-------
levels in the vi.cin.Lty of producer rind user plants were lacking. A sampling
rationale and protocol were established. During late 1976 and early 1977,
samples were collected from various production sites, a user site, and A
background site. The samples were analyzed and Uie results are summarized
in Table 2.9 and 2.10. Details of the results and methodology can he found
in a companion report (Battelie Columbus Laboratories, 1977).
Discussion of the Data
The concentration of trichloroethylene in the atmosphere ranges from
about 1 ppt in remote areas to over 100 ppb in areas where the substance is
manufactured or used. 1'earson and McConncJl (1975) point out that as one
moves away from a manufacturing facility, the conceiti at.Lon of trichloro-
ethylene in air drops off rapidly. These results are summarized in Table 2.7.
Ohta and coworkers (1.976) make a similar observation. They state that the
distribution peak for trichloroethylene coincides with locations of machine
or met.'il product plants which use the solvent.
The BatLelle Columbus Laboratories (1977) study in the United States
confirms these observations. In Table 2.9, the highest concentrations of
trichloroethylene are observed downwind from a producer or user site and
the concentration seems to be dependent on the dibtance from the discharge
point. Most of the higher concentrations are observed at distances of less
than 1 kni. Considerable variation, however, was observed in the maximum
downwind levels of trichloroethylene at various production sites. The
variations in the observed maximum concentrations between plants may be
due to differences in (1) production processes, (2) emission control
equipment, (3) meteorological conditions, and (A) distance from the plant.
2-19
-------
TABLE 2.9. CONCENTRATION RANGES FOR TRICHLOROETHYLENK TN THE
ATMOSPHERE AROUND PRODUCER AND USER SITES
Date of
Location Collection
Dow Chemical Co. Nov. 1976
Freeport TX
Hooker Chemical Nov. 1976
Hahnvillc LA
Ethyl Corporation Nov. 1976
Baton Rouge LA
PPG Industries Dec. 1976
Lake Charles LA
Boeing Company Jan. 1977
Seattle WA
(user)
St. Francis Na- Nov. 1976
tional Forest AK
(background)
Concentration, Distance
Site ppba from Plant
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
1
2
3
4
_
-------
TABLE 2.10. CONCENTRATION OF TRICHLOROETIIYLENE IN WATER, SOCL,
AND SEDIMENT IN THE VICINITY OF PRODUCER SITES
Location
Date of
Collection
Description of Medici
Concentration,
ppb
Dow Chemical Co., Nov. 1976
Plant B, Freeport TX
Hooker Chemical Co.
Hahnville LA
Nov. 1976
13
0.9
<0.06 to 0.45
0.15
None detected
0.04
Surface water, mouth of 172
plant effluent canal
Water, as above except 4 m 197
deep
Surface water, 400 m down- 5
stream from plant outfall
Water, as above except 5—
6 in deep
Surface water, 800 m
upstream of plant outfall
Soil, approximately 2 km
from plant:
Sediment, mouth of plant
effluent canal
Sediment, 400 in downstream
of plant ouLfall
Sediment:, 800 111 upstream
of plant out Fall
Surface water, Mississippi 1
River, 150 m upstream of
plant outfall
Surface water, at plant 535
outfall
Surface water, 1 km down- 22
stream of plant outfall
Surface water, open stag- 5,227
nant canal about 2.7 km
from plant
Soil, close to the plant out 0.23 to 5.6
to about 2.7 km
Sediment, 150 m upstream 0.18
of plant outfall
Sediment, 100 m downstream 0.63
of plant outfall
Sediment, 200 m downstream 0.03
of plant outfall
2-21
-------
TABLE 2JO (Continued)
Location
Ethyl Corpor.it ion
Baton Rouge LA
PPG lndusLri.es
Lake Charles LA
Date oE
Collection DescrLption of Media
Nov. 1976 Surface water immediately
above settling pond
Surface water, 200 m
upstream of plant outfall
Surface water, 300 m down-
stream of plant outfall
Soil , various locations in
vicinity of plant
Sediment, 200 m upstream
of plant outfall
Sediment, 300 m downstream
of plant outEall
Dec. 1976 Surface water, 50 m
upstream of plant outfall
Surface water , at plant
outfall No. 1
Surface water, at plant
outfall No. 2
Surface water, 50 in doxm-
stream of outfall No . 2
Surface water, lake — down-
Concentration ,
ppb
128
0.4
37
None detected
None detected
116
353
447
179
403
29
St. Francis National
Forest AK
(backgrotmd)
Nov. 1976
stream of plant outfalls
Soil, quadrants surrounding
plant
Sediment, 50 m upstream
oE plant outfall
Sediment, at plant outEall
No. 2
Surface water, from lake
Soil
Sediment
None detected
to 0.11
146
15
<0.05
0.63
2.2
2-22
-------
Higher production capacity apparently does not necessarily imply higher
emissions since the maximun concentrations observrd at the larger: plants
were no higher than those observed at the smaller operations and sometimes
lower. Large temporal variations are observed when measurLng these
chlorinated hydrocarbons downwjnd from a production facility. Changes in
meteorological conditions, particularly wind speed and direction, and/or
variations in the emissions may account for this phenomenon.
The range of concentrations in surfoce waters is more difficult to
judge. The analytical techniques presently used do not allow routine
determinations at the ppt level. So the actual backgroundjhas to be taken
as somewhat less than 1 ppb. However, surface waters in urban areas can
have concentrations on the order of 100 ppb.
The study by the Institute for Environmental Studies (Chian and Ewing,
1976) indicates the concentration of trichlnroethylene in surface waters
may be as high as 188 ppb (in the vicinity of Lake Erie), but for the most
part surface waters contain less than .1 ppb (Table 2.8.)-
In the Battellc study carried out in the vicinity of manufracturing
plants, the concentration of trichloroethylene was higher (Table 2.10). One
sample went as high as 5 ppm. Again, the distance from the source was
important as the concentration dropped off with distance. Also, samples
upstream from plant discharge channels usually had lover concentrations than
samples taken downstream.
The literature provides no information on the presence of trichloro-
ethylene in soil. In the Battelle study, it was found that the concen-
tration of trichloroethylene in soil in the vicinity of manufacturing plants
2-23
-------
was on the order of a few ppb or less (Table 2.10); but unexpectedly, the
same concentration was found at a background site in Arkansas. Sediment
samples analyzed in this same study showed more variable results. Concen-
trations ranged from less than 0.04 ppb to as high as 146 ppb (Table 2.10);
but again the rural background site showed a level of 2.2 ppb which was higher
than anticipated.
It is clear that the source of trLchloroethylene is anthropogenic, tt
is at highest concentration where it is made and used. The background level
in the atmosphere is Cairily low, on the order of 5 ppt, indicating that
trichloroethylene is degraded in the atmosphere. However, in close proximity
to manufacturing or user plants the concentration may be considerably higher
and at tlines m.iy approach !1 ppm.
2-24
-------
3. BEHAVIOR OF TRICHLOROETHYLENE IN THE ENVIRONMENT
PHYSICAL/CHEMICAL CHARACTERISTICS OF TRICHLOROETHYLENE IN THE ENVIRONMENT
This sectLon might also be considered the degradability section since
the data contained herein deals with how long trichloroethylene holds up in
the environment and in the human body. Table 3.1 brings together some of.
this information.
The structure of the compound dictates its behavior in the environment.
Trichlorocdiylene is an uns&turated chlorinated hydrocarbon. The double
bond is susceptible to attack by free radLcals and electrophilic reagents.
Thus, it is not suprising that it is easily degraded in a photochemical
environment such as ambient aLr. On the other hand, since the vinyl bond
between carbon and chlorine is very strong, this molecule is not susceptible
to hydrolysis and is relatively stable in water and in the soil.
Some researchers have concluded that "... not only are the simple
chloroa.Lipliat.Lc compounds not particularly persistent, but their degradation
products are simpJe species commonly found in the environment" (McConnell
et a.l . , 1975). This statement needs to be accepted with some reservations
for there is still the question of how quickly the "simple species commonly
found in the environment" form and of what the intermediates in these processes
might be. The next section attempts to answer these questions.
3-1
-------
TABLE 3.1. PHYSICAL/CHEMICAL CHARACTERISTICS OF
TRICHLOROETHYLENE IN THE ENVIRONMENT
Media
Half-Life/Changc
Reference
Human blood; after
human exposure at
100 ppm, 6 h/10 days
Ditto
Human, anaesthesia
Human
SJimi.lal.ed atmospheric
condition0-
One ppm In waLcr
contninJng naturaJ
and added contami-
nants
Troposphere, 3.1
parts/thousand
13.3 hr/trichloroethanol Mueller et al., 1974
disappearance
99 hr/trichloroacetJc
acid disappearance
min/chloral hydrate
from blood
hr/urinary meta-
bolites excreted
Estimate 5-.12 hr under
bti.glit sunlight
19 irrln/evaporat Lon
6 weeks (±50%)
Cole et al., 1975
Ikeda and Imamura, 1973
Dilling et al., 1976
Pearson and McConnell, 1975
3-2
-------
TRANSFORMATIONS OF TRICIILOkOKTHYLENF, IN THE ENVIRONMENT
This section indicates what new substances are produced when
trichloroethylene enters the environment. This information is summarized
in Table 3.2. Figure 3.1 shows the transformations of trichloroethylene
schematically. Figure 3.2 shows the degradation of trichloroethylene in a
photochemical chamber in the presence of nitrogen/dioxide in air (Gay et al.,
1976). The chamber was irradiated with ultraviolet light as the reactants
and products were continuously monitored using longpath infrared spectroscopy.
This study was undertaken in order to obtain more information on the atmo-
spheric degradation of halogenated compounds particularly with regard to the
rates of photooxidation and the identity of photooxidation intermediates
and final products.
What is seriously needed in this area .is the same kind of study on
a more comprehensive environmental scale. What is the rate, fate, and
transport mechanism for the dispersion and degradation of trichloroethylene
in the environment? Perhaps this can best be determined in studies of
model ecosystems using labeled compounds as tracers and sophisticated
analytical procedures for the analysis of the substances and their degra-
dation products. Radiolabeled trichloroethylene (trichloroethylene
[1,2-^Cj) is available from various suppliers on special order.
In looking at the various transformations of trichloroethylene, the
question of the toxiciLy of the intermediates arises. Some of the compounds
that are produced are simple molecules that have been previously studied.
These are carbon dioxide, carbon monoxide, hydrogen chloride, chlorine,
acetic acid, and ozone; but others such as dichloroacetic chloride, phosgene,
3-3
-------
TABLE 3.2. TRANSFORMATIONS OF TRICHLOROETHYLENE
IN THE ENVIRONMENT
Media
What is Produced
Reference
Photochemical Chamber,
TCE (3.45 ppm) with
toO^ (^-&6 ppm)
Atmosphere near
welding
Smog chamber
Human (LOO ppm,
6 h/10 clays)
Atmosphere, xenon arc
exposure
Dichloroacetyl chloride,
HC1, CO, phosgene
(TCE haLE-liEe: ^2 hr)
I1C1, C1.2, and phosgene
(severe decomposition,
dangerous levels)
Ozone
Trichloroethanol and
tr.Lchloroac.efLc acid in
blood
Dlchloroacet.ic acid,
C02, HC1
Gay et al., 1976
Rinzema and Silverstein,
1972
Farber, 1973
McNutt et al., 1975
McConnell et al., 1975
3-4
-------
Trichloroethylcne
Dicliloroacetyl
Chloride
20 40 60
80 100 120 140 160
TIME IN (min.)
180 200
Figure 3.1. Reactants and products of trich]oroethylene
and NO,
1976).'
and NO irradiation (Source: Gay ot al .,
3-5
-------
C12C = CHC1
OJ
Human Metabolism
Biological t-l/2a 41 hr'
(Ikeda & Imaraura, 1973)
[C13CCH(OH)2]
(Chloral Hydrate)
t-1/2 5-12 hr (bright sunlight) (Billing et al . , 1976)
t-l/2a 6-12 weeks (McConnell et al., 1975)
NO,
C13CC02H
Water,
Soil
Persists 2-18 months
(Abrams et al., 1975)
or
2.5 years
(Pearson &-McConnell, 1975)
ClgCHCOCl, HC1, 03, C1COC1, CO, HCOgH, HNOg
4 (phosgene) ((.ay efc ^ ig?6)
C12CHC02H
C02," HC1
Microorganisms
in Sea Water
V
Unknown
Degradation Products
(McConnell et al., 1975)
t-1/2 = Time required for one-half of the chlorinated
hydrocarbon to disappear by the indicated process.
Figure 3.2. Transformations of trichloroethylene.
-------
and dichloroacctic acid arc not commonly found in the environment and may
be of some concern. The toxicity of. these materials is addressed in the next
section. The evidence ns that phosgene, although extremely toxic, is not
produced in very large amounts except under special circumstances such as
when high concentrations of trichlorocthylene are present in the atmosphere
where welding Ls taking place. According to Pearson and McConnell (1975)
any phosgene produced in the atmosphere would he quickly hydrolyzed to carbon
dioxide £ind hydrogen chloride.
There are other special circumstances that could produce toxic
substances. Trichloroethylene in the presence of a strong base or at high
temperatures is converted to dichloroacetylcnc which is extremely toxic but
is quickl} converted by moisture to phosgene. Thes3 toxic products of
trichloroethylcne would not be expected to exist in significant concen-
trations for any length of time under normal circumstances in Lhe environment.
The only degradation products that may exist i.n the environment in
appreciable quantities for ciny period of time arc dichloroacetyl chloride
produced by the photodcgrndatLon of trichlorocLhylene in the atmosphere and
dichloroacctic acid produced by the hydrolysis of dichloroacetyl chloride.
Limited animal, experimentation suggests low toxicity for dichloroacetyl
chloride although it may be irritating to eyes and mucous membranes. There
is also little information available on dichloroacetic acid (see next section)
There is some evidence that the ultimate fate of the dichloroacetyl chloride
and dichLoroacetic acid is degradation by microorganisms (McConnell et al.,
1975). Although the degradation products have not been determined, they are
probably carbon dioxide cind chloride ions which are already present in the
3-7
-------
environment. The effect of dichloroacetyl chloride on the environment and
its ultimate fate should, however, be determined since such large quantities
of trichloroetliylene are being released into the atmosphere and degraded
each year.
TOXICOLOGY OF TRIC1ILOROET1IYLENE AND [TS POSSIBLE DEGRADATION PRODUCTS
In the introduction to this section on trichloroethylene, some of the
reasons for the concern over this substance were enumerated; but boiled down,
this concern amounts to the fact that a large amount of this material is
produced and used by people who are exposed to it and who may be directly
or indirectly harmed by such exposure. This section attempts to answer the
question: In what way does, or might trichloroethylene harm people?
There are several reviews on the toxicity and toxicology of
trichloroethyJ.ene. A recant and comprehensive reviex* by Avaiado et al.,
1976, is available arid the toxicity oE thJs substance is discussed at
length in the review by the U.S. Environmental Protection Agency (1975).
Biological studies and toxicology of trichloroethylene are discussed in
other reviews as wo LI (National Institute for Occupational Safety and Health,
1973; Waters, et al., 1976; World Health Organization, 1976). Of somewhat
older vintage is the text by Browning (1965)| dealing with industrial solvents
in general and specifically with trichloroethylene. Some of this information
will be summarized here.
Regardless of the exposure of a substance, there :is no harm possible
unless there is some interaction with the organism. Figure 3.3 shows the
uptake of trichloroethylcne and other solvents in relation to the
3-8
-------
%
uptake
80
60
40
20
20
40
60
80
O Methylene chloride
\
$• TrichloroethyJLene
D Aliphatic white ^spirit
H Aromatic white spirit
A Styrene
alveolar concentration x 100
i-nspiratory concentration
Figure 3.3 Uptake (percentage of amount supplied) in relation to alveolar
concentration (percentage of concentration in inspiratory air)
after 30 minutes of exposure at rest and during exercise.
(Each symbol gives the mean value of two subjects for styrene
and the aliphatic and aromatic components of white spirit, the
mean value of four or five subjects for raethylene chloride,
and the mean value of five subjects for trichloroethylene.
{Regression line: y = -0,72x = 74.91) (Source: Astrand,
1975).
3-9
-------
concentration in inspiratory air. This figure was taken from a review by
Astrand (1975) on the uptake of solvents in the blood and tissues of man.
Once inside the body the inhalation (as above) or through skin absorption
(Fukabori et al., 1976) or by ingestion (U.S. Environmental Protection
Agency, 1975), this substance is rapidly metabolized and the major products
are excreted. The metabolites are trichloroethanol, trichloroethanol
glucuronide, and trichloroacetic acid. Monochloroacetic acid is also a
detectable trichloroethylene metabolite. Chloral hydrate is a demonstrated
intermediate in the metabolism of trichloroethylene to trichloroethanol
and trichloroacetic acid (Cole et al., 1975).
It is obvious then that trichloroethylene is taken into the body and
interacts (is metabolized) with it. The question now becomes, what effect
does this interaction have on the tissues of the organism? Table 3.3
summarizes the toxicity of trichloroethylene and compares it with related
compounds (Waters et al., 1976). The U.S. Environmental Protection Agency
(1976) summarized trichloroethylene health effects. Trichloroethylene has
been responsible for the death of humans. One study reports on trichloro-
ethylene poisoning in 284 cases, including 26 fatalities, in European plants
where trichloroethylene vapors were inhaled. Toxic action involves the
central nervous system. Short-term studies indicate that exposure to a
concentration of 100 ppm in air may interfere with psychophysiological
efficiency. Six students exposed to 110 ppm from two 4-hour periods
separated by 1-1/2 hours showed significantly lower levels of performance
in perception, memory, and manual dexterity tests.
Recently as a part of a continuing NCI bioassay program to screen
chemicals for cancer-causing activity, trichloroethylene was tested and
3-10
-------
TABLE 3.3. COMPARATIVE TOXICITY OF TRICHLOROETHYLENE AND RELATED COMPOUNDS
Compound and
parent alkane
Chloroform
(Methane
Enhalation, LC50,
Oral LD50 rag/kg
Rat: 800
Rat: 2,180
ppm
Mouse: 5,
Mouse:
Rabbit:
Dog:
687/7 hr
28
59
100
Lowest published toxic
concentration, ppm
Human : 10/yr
Systemic effects
Structural
forms
Cl
1
Cl-C — H
1
Cl
derivative)
Carbon tetra-
chloride
(Methane
derivative)
1,1,1-Trichloro-
ethane
Mouse: 12,800
Rat: 1,770
Rat: 7,460
Rabbit: 6,380
Guinea
Pig: 9,470
Rabbit: 5,660
(Ethane
derivative)
1,1,2-Trichloro-
ethylene
Rat:
Rat:
Dog:
5,200
4,920
5,900
Mouse: 9,526/8 hr
Mouse: 9,528/7 hr
Rat: 23,900/30 min
Rat: 14,000/7 hr
Rat: 18,000/3 hr
Human:
CNS:
20
toxic effects
Human: 350
Psychotrophic effects
Human: 920/70 min
CNS: toxic effects
Cl
I
Cl- C -
I
Cl
Cl
Cl —
Cl
1
C —
1
Cl
H
1
C
1
H
•— • H
Human: 160/83 min
CNS: toxic effects
Human: 11C/8 hr
Cl
Cl
C = C
/ \
Cl
H
-------
TABLE 3.3. (Continued)
Compound and Inhalation, LC50, Lowest published toxic Structural
parent alkane Oral LD50 mg/kg ppm concentration, ppm forms
(Ethylene
derivative)
i-j
NJ
1,1,2,2-Tetra-
chloroethylene Mouse: 8,850
Mouse: 10,900
(Ethylene
derivative)
Source: Waters et al., 1976.
Human: 230
Systemic effects
Human: 280/2 hr
Eye: toxic effects
Human: 600/10 min
CNS: toxic effects
Cl
\
Cl
Cl
Cl
-------
found to be active in mice (Anonymous, 1976). Much of the data is described
in that HEW News release. The report goes on to day that investigations of
compounds that can be substituted for trichloroethylene (such as methyl-
chloroform) are underway, but NCI states concern regarding substitution for
trichloroethylene before the alternative compounds can be adequately
evaluated.
The carcinogenicity of trichloroethylene has also been reviewed
recently by the International Agency for Research on Cancer (World Health
Organization, 1976).
Table 3.4 presents a summary of carcinogenic data for trichloroethylene
(Waters et al., 1976). The question remains whether any relationship exists
between tiichloroethylene and liver cancer in man. Until that is resolved,
trichloroethylene must be regarded as a useful but potentially hazardous
substance.
In the section on "Transformations of Trichloroethylene in the
Environment", some of the known transformations of trichloroethylene in the
environment were indicated. In considering the possible harm of a substance
to people or to animals, it is not sufficient to know the toxicity of the
parent compound; the toxicity of the degradation or transformation products
must also be considered and evaluated in terms of the quantities of these
by-products produced. Table 3.5 provides a summary of the toxicity of
trichloroethylene and its various transformation products. Unfortunately,
little is known about the quantities of these substances that are produced
when trichloroethylene is degraded.
3-13
-------
TABLE 3.4 SUMMARY OF DATA ON THE CARCINOGENICITY
OF TRICHLOROETHYLENE
Species
Number
Exposure
Results
Dogs 16
Rats 12
Guinea pigs 11
Monkeys 2
Rabbits 4
Cats
Mice 28
Rats
Inhalation
150-750 ppm in air 20-48 hr/wk
for 7-16 wk
Inhalation
3,000 ppm, 27 exposures
100 ppm, 132 exposures
200 ppm, 148 exposures
200 ppm, 178 exposures
Inhalation
200 ppm 75 min/day for 6 rao
Intragastric
0.1 ml in 40% oil solution 2/wk
2,339 mg/kg (M) 5 wk for 78 wk
1,739 mg/kg (F) 5 wk for 78 wk
1,169 mg/kg (M) 5 wk for 78 wk
869 mg/kg (F) 5 wk for 78 wk
Intragastric
1,097 mg/kg (M&F) 5/wk for 78 wk
549 mg/kg (M&F) 5 wk for 78 wk
No tumors, no deaths
3 rats died, no tumors
No tumors, no deaths
No tumors, no deaths
Hepatocellular carci-
noma; Metastases,
mainly lung
No hepatocellular
carcinoma, many deaths
from toxic doses
during experiment
Source: Waters et al., 1976.
3-14
-------
TABLE 3.5. TOXICITY OF TRICHLOROETHYLENE AND ITS TRANSFORMATION PRODUCTS
Compound
Toxicity
Threshold Limit Value
Trichloroethylcne
Chloral hydrate
orl-hmn LDLo
ihl-hmn TCLo
ihl-man TCLo
orl-rat LCLo
orl-mus TDLo
TFX:CAR
ihl-mus LCLo
ivn-mus LD50
orl-dog LDLo
ipr-dog LD50
ivn-dog LDLo
ihl-rbt LCLo
scu-rbt LDLo
orl-rat LD50
ipr-rat LDLo
scu-rat LD50
orl-mus LD50
skn-mus TDLo
TFX:NEO
ipr-mus LDLo
scu-mus LDLo
orl-dog LDLo
orl-cat LDLo
orl-rbt LDLo
scu-rbt LDLo
ivn-rbt LDLo
rec-rbt LDLo
orl-frg LDLo
par-mus LDLo
:857 mg/kg
:160 ppm/83M TFX:CNS
:110 ppm/8H
:8000 ppm/4H
:351 gm/kg/78WI
:3000 ppm/2H
:34 mg/kg
:5860 mg/kg
:1900 mg/kg
:150 mg/kg
:11000 ppm
:1800 mg/kg
:285 mg/kg
:500 mg/kg
:620 mg/kg
:1100 mg/kg
:960 mg/kg/W
: 650 mg/kg
:800 mg/kg
:1000 mg/kg
:400 mg/kg
:1200 mg/kg
:1000 mg/kg
:400 mg/kg
:1000 mg/kg
:938 mg/kg
:900 mg/kg
100 ppm *>535 mg/m
U.S. OCCUPATIONAL STANDARD USDS
air TWA:100 ppm; C:200 ppm;
PK:300 ppm/5M/2H
GRIT DOC: RECOM. STANDARD air
TWA:100 ppm:C 150 ppm
-------
TABLE 3.5 (Continued)
Compound
Toxicity
Threshold Limit Value
Trlchloroethanol
Triehloroacetic acid
Dichloroacetic acid
Formic acid
Hydrochloric acid
Hydrogen chloride
orl-rat LD50:600 mg/kg
ipr-rat LDLo:300 mg/kg
ivn-tnus LD50:201 mg/kg
ivn-rbt LDLo:50 mg/kg
orl-rat LD50:3320 mg/kg
irp-mus LDLo:500 mg/kg
orl-rat LD50: 2820 mg/kg
skn-rtb LDSO:510 mg/kg
orl-rat LD50:1210 mg/kg
orl-mus LD50:1100 mg/kg
ipr-mus LD50:940 mg/kg
irn-mus LU50:145 mg/kg
orl-dog LD50:4000 mg/kg
ivn-rbt LDLo:239 mg/kg
ihl-hmn LCLo:1300 ppm/30M
ihl-rat LC50:3124 ppm/lH
ihl-mus LC50:2142 ppm/30M
ipr-mus LD50:40 mg/kg
orl-rbt LD50:900 mg/kg
ihl-rat LC50:470L ppm/30M
ihl-mus LC50:2644 ppm/30M
ihl-rbt LCLo:4416 ppm/30M
ihl-gpg LCLo:4416 ppm/30M
ihl-mam LCLorlOOO mg/m3/2H
5 ppm ^9 mg/m
5 ppm ^7 mg/m~
-------
TABLE 3.5 (Continued)
Compound
Toxicity
Threshold Limit Value
Ozone
Phosgene
Chioroacetyl chloride
Dichloroacetyl chloride
Carbon monoxide
ihl-man TCLo:1860 ppb/75M
TFXrCNS
ihl-hmn TCLo:100 ppb TFXrIRR
ihl-hmn TCLorl ppm TFX:PUL
ihl-rat LC50:4.8 ppm/4H
ihl-mus LC50:3.8 ppm/4H
ihl-mus LCLo:4.5 ppm/50HI TFX:NEO
ihl-ham LC50:10.5 ppm/4H
ihl-hmn TDLo:25 ppm/30M TFX:IRR
ihl-rat LC50:75 ppm/30M
ihl-mus LC50:110 ppm/30M
ihl-dog LCLo:79 ppm/30M
ihl-mky LC50:1087 ppm/lM
ihl-cat LC50:1482 ppm/lM
ihl-rbt LC50:3211 ppm/lM
ihl-gpg LC50:141 ppm/30M
ihl-gpg LDLo:31 mg/m3/20M
ihl-rat LCLo:1000 ppm/4H
orl-rat LD50: 2460 mg/kg
ihl-rat LCLo:2000 ppm/4H
skn-rbt LD50:650 mg/kg
ihl-man LCLo:4000 ppm/30M
ihl-man TCLo":650 ppm/45M TFX:"CNS "
ihl-rat LC50:1807 ppm/4H
ihl-mus LC50:5718 ppm/4H
ihl-dog LCLo:3841 ppm/46M
ihl-cat LCLo:8730 ppm/35H
ihl-gpg LC50:2444 ppm/4H
01 ppm ^02 mg/m
50 ppm ^55 mg/m"
Nitric "acid'
-_ O
2 ppm 'v/S' mg/m-3
-------
TABLE 3.5 (Continued)
Key to Abbreviations
i-1
00
AZTX - aquatic toxicity
CNS - central nervous system
gpg - guinea pig
H - hour
hum - human
ihl - inhalation
ipr - intraperitoneal
ivn - intravenous
LC50 - lethal concentration 50% kill
LCLo - lowest published lethal
concentration
LD50 - lethal dose 50% kill
LDLo - lowest published lethal dose
M - minute
mam — mammal
mus - mouse
pph - parts per hundred (V/V)(percent)
Pfy - psychotropic
Pk - peak concentration
rbt - rabbit
rec - rectal
scu - subcutaneous
skn - skin
TCLo - lowest published toxic concentration
TDLo - lowest published toxic dose
TFX - toxic effects
TLV - threshold limit value
TWA - time weighted average
TXDS - qualifying toxic dose
USOS - U.S. Occupational Health Standard
Source: Christensen and Luginbyhl, 1975.
-------
4. OCCURRENCE OF TRICHLOROETHYLENE IN FOOD AND
OTHER PRODUCTS THAT COME IN CONTACT WITH MAN
FOOD
There are, unfortunately, very little data on the presence of TCE
in food raised and sold in the United States. There is some informa-
tion on the presence of TCE in foodstuffs found in the United Kingdom.
This information is summarized in Table 4.1. TCE is found on the order
of parts per billion in almost all common foodstuffs.
Trichloroethylene has also been used to extract spice oleoresins
and to decaffeinate coffee. The FDA regulations of the concentration
of TCE in these materials are listed in the section on "Exposure and
Biological Accumulation of Trichloroethylene in Man". In 1974,
approximately 90 percent of the decaffeinated coffee was produced
using trichloroethylene (Valle-Riestra, 1974); but since July, 1975,
TCE has not been used by U.S. makers of decaffeinated coffee. It has
largely been replaced by methylene chloride, according to FDA, even
though the safety of methylene chloride has not been established. In
a recent publication, TCE was not detected in any of the oleoresins
analyzed for that substance (Page and Kennedy, 1975).
DRINKING WATER
Shortly after the identification of trichloroethylene and other
halogenated hydrocarbons in New Orleans drinking water, the results
were published (Dowty et al., 1975a and 1975b) and several other
significant events occurred. The Safe Drinking Water Act was signed
into law in December, 1974, and a National Organics Reconnaissance
Survey (NORS) was undertaken.
4-1
-------
Table 4.1 TRICHLOROETHYLENE IN FOODSTUFFS
Foodstuff Concentration, pg/kg
Dairy produce
Fresh milk 0.3
Cheshire cheese 3
English butter 10
Hens eggs 0.6
Meat
English beef (steak) 16
English beef (fat) 12
Pig's liver 22
Oils and fats
Margarine 6
Olive oil (Spanish) 9
Cod liver oil 19
Vegetable cooking oil 7.
Castor oil ND
Beverages
Canned fruit drink 5
Light ale 0.7
Canned orange juice ND
Instant coffee l\
Tea (packet) 60
Wine (Yugoslav) 0.02
Fruit and vegetables
Potatoes (S. Wales) ND
Potatoes (N.W. England) 3
Apples 5
Pears 4
Tomatoes 1.7
Black grapes (imported) 2.9
Fresh bread 7
a Tomato plants were grown on a reclaimed lagoon at Runcorn
Works of ICI.
b ND = not detected.
Source: McConnell et al., 1975.
4-2
-------
As part of the NORS, drinking water supplies at five selected
sites were analyzed. These supplies were chosen to represent the
major types of raw water sources in the United States at that time.
The results for ICE are summarized in Table 4.2. The NORS was extended
to cover a total of 10 cities in the United States. In the extended
survey, trichloroethylene was also detected but not quantified in the
drinking water of Lawrence, Massachusetts (U.S. Environmental Protection
Agency, 1975b). A follow-up study on finished and raw water samples
from Miami, Florida, was carried out. The results of this study are
summarized in Table 4.3.
Several U.S. Environmental Protection Agency regional offices
have analyzed various waters for TCE. The Surveillance and Analysis
Division of Region IV under the direction of James H. Finger has
detected TCE at the following locations at the estimated concentrations
shown:
Dalton, Georgia, Wastewater Treatment Plant - < 5 ppb
Rome, Georgia, Treatment Plant - < 0.5 ppb
Rome, Georgia, Wastewater Treatment Plant - < 5 ppb.
Region IV personnel also analyzed discharge from the Stauffer Chemical
Co. plant at Louisville and determined the TCE concentration to be 500 ppb.
It is believed that Stauffer produces TCE at this plant. Region IV
personnel may have conducted an organics study of the Ohio River, but
this information is not yet available.
As a result of a National Organic Monitoring Survey conducted
between March 1 and April 3, 1976, which indicated that trichloroethylene
was present in the finished drinking water at Des Moines, Iowa, to the
4-3
-------
Table 4,2 PROPERTIES AND TCE CONCENTRATION OF FINISHED WATER IN FIVE CITIES
Type
of
City supply
Cincinnati, Surface
Ohio
Miami, Ground
Florida
Ottumwa, Surface
Iowa
*• Philadelphia, Surface
*• Pennsylvania
Seattle, Surface
Washington
Type Nonvolatile
of raw total organic
water carbon, mg/1
Industrial 1.3
waste
Natural 6.5
waste
Agricultural 2.3
waste
Municipal 1.9
waste
Natural 1.0
waste
TCE
Conductivity, Chlorine, concentration,
MMHOS/CM mg/1 pH ppb
295 2.7 8.6 0.1
350 2.3 8.7 0.3
500 1.4 9.2 <0.1
260 2.0 8.3 0.5
50 0 6.6 ND
ND = not detected.
Source: Keith, 1976.
-------
Table 4.3 SOME OF THE ORGANIC COMPOUNDS IDENTIFIED IN
MIAMI, FLORIDA-FINISHED AND RAW WATER SAMPLES
Organic
compound
identified
Trichloroethylene
Methylchloroform
Carbon Tetrachloride
Chloroform
Finished
water,
1/29/75,
ppb
Pa
P
P
311
Finished
water,
7/7/75,
ppb
P
P
P
220
Raw
water ,
7/7/75,
ppb
P
P
ND
0.7
Test
wall,
7/7/75,
ppb
NDb
ND
ND
ND
Source: Keith, 1976.
a P = Present but not quantified.
b ND = Not detected.
4-5
-------
extent of 32 ppb, the Surveillance and Analysis Division of Region VII
under the direction of Donald A. Townley became involved in a rather
extensive sampling and analysis effort. This effort was lead by
Dr. Robert D. Kleopfer, Organic Chemistry Working Unit Leader,
Laboratory Branch, Region VII. Following is a summary of the results
obtained in this study.
Samples taken at Des Moines, Iowa, on August 4, 1976, were
analyzed using a Tekman liquid sample concentrator with computerized
gas chromatography/mass spectrometry. Raw water was determined to
have no detectable TCE while the finished water contained TCE at a
concentration of 53 ppb. Then on August 12, 1976, a more extensive
series of samples were taken.| The results are reproduced in Table 4.4.
It was concluded that the TCE originates in the gallery infiltration
system and is not being produced in the water treatment process.
The next step was to attempt to determine the ultimate source of
TCE by sampling the infiltration gallery at various points along the
system. The gallery system is approximately 3 miles in length and
access by manholes is available at 2,000-foot intervals. Assuming
a flow of 25 million gallons per day through the gallery\and a TCE
concentration of 61 ppb, the source would have to provide 5,772 g
(12.7 Ibs.) or 3.95 liters (1.04 gallons) of TCE per day to the
infiltration gallery water. On September 2, 1976, samples were taken
at various points along the gallery. The samples were analyzed and the
results are summarized in Table 4.5. It was concluded that contamination
of the gallery infiltration system was responsible for the presence
of TCE in Des Moines drinking water and that the contamination occurs
4-6
-------
Table 4.4 TCE CONCENTRATION IN WATER SOURCES FOR DBS MOINES, IOWA,
DRINKING WATER AND IN CONTROLS
Sample description
Concentration, ppb
Raccoon River at Rock Dam
recharge pumping station
Raccoon River water treated
with hypochlorite
Gallery infiltration water
Gallery infiltration water
treated with hypochlorite
Raccoon River water from
sedimentation basin
Mixed water prior to softening
Mixed water after softening
Finished water at Des Moines Airport
Finished water at water treatment
plant laboratory
Kansas City, Kansas, water trans-
ferred at water treatment plant lab
Meredith Canal
Meredith Canal just prior to recharge
basin
NDe
ND
61
33
ND
39
41
24
31
ND
11
a ND = none detected; the detection limit was 1 ppb.
4-7
-------
Table 4.5 TCE CONCENTRATION IN INFILTRATION GALLERY AND
IN ASSOCIATED WATERS
Sample description Concentration, ppb
Meredith composite at west
end of creek 1
Meridith composite of process
water at north end of building 8
Meredith composite of process
water at east end of creek 12
Meredith grab of process water
at east end of creek 14
Meredith canal grab just prior
to recharge basin 2
Grab at Cabin Creek bridge NDa
South bank at middle of west
part of recharge basin #14 1
Gallery at manhold #12 ND
Gallery at valve chamber #11 ND
Gallery at valve chamber #10 ND
Gallery at valve chamber #8 ND
Gallery at valve chamber #5 ND
Gallery at water plant 45
Raccoon River at intake ND
Finished water at lab 22
a ND = not detected; the detection limit was 1 ppb.
4-8
-------
somewhere downstream from Valve Chamber Number 5. On September 22
and 23, 1976, samples were taken downstream from Valve Chamber Number 5
and at other sites. The analytical results are presented in Table 4.6.
These results show that the north end of the gallery is heavily con-
taminated by TCE. The exact source of this substance has not been
reported at this writing. Table 4.7 summarizes the data for Des Moines
finished water.
It is interesting to note that the levels of TCE reported in
Des Moines, Iowa, drinking water may result from the dumping of 1
gallon per day of this substance into the water system.
In an earlier, unrelated study (1974), raw wastewater processed
in the Oro, Iowa, Sanitary District of the San Francisco Bay was esti-
mated to contain 1.2 mg per liter in the 49,205 cubic meters per day
average discharge (Camisa, 1975).
In an investigation of the chlorination of water for purifica-
tion and the potential for the formation of potentially harmful chlori-
nated compounds by this process, T.A. Bellar, et al (1974) at the
National Environmental Research Center of EPA at Cincinnati, Ohio,
reported the following concentrations of trichloroethylene in water
from a sewage-treatment plant: Influent before treatment, 40.4 p,g/j&;
effluent before chlorination, 8.6 p,g/A; and effluent after chlorination,
9.8 ng/jt. These workers concluded that the number of organohalides formed
during the chlorination process does not constitute any immediate threat
to the public health.
The prevalence of TCE and other halogenated hydrocarbons in the
environment cannot be denied. However, the source of these substances
4-9
-------
Table 4.6 TCE CONCENTRATIONS IN NORTH END OF INFILTRATION
GALLERY AND IN ASSOCIATED WATERS
Sample description Concentration, ppb
,a
j
Gallery pump discharge 37*
Laboratory tap (9/23/76) 16C
,a
River intake ND
Valve chamber #1 391a
Manhole #1 457a
Manhole #2 229a
Birds Run sewer overflow ND
Raccoon River below dam ND
Raccoon River near steel sheeting ND
Drainage culvert ND
ft
Sewer manhole west 151
a These samples all contained lesser amounts of dichloro-
ethylene.
b ND = not detected; the detection limit was 1 ppb.
c This sample contained significant amounts of TCE, methyl-
chloroform and dimethyldisulfide with smaller amounts of
dichloroethane and dichloroethylene.
4-10
-------
Table 4.7 SUMMARY OF TCE DATA FOR DES MOINES FINISHED WATER
Date of sample
December 10 or 11, 1974
March 20, 1975
March-April, 1976
Spring, 1976
August 4, 1976
August 12, 1976
August 12, 1976
September 2, 1976
Location
At Plant
Ditto
it
ii
it
ii
At Airport
At Plant
Concentration, ppb
Pa
80a
32b
53b
53
31
24
22
a Two analyses were done by the Iowa State Hygienic Laboratory;
the earlier sample indicated a "third peak" which was tenta-
tively identified as trichloroethylene.
b These samples were taken as part of a national survey.
4-11
-------
in such media as drinking water has not been determined. Much more
information about the presence of these substances in the environment
is needed as well as information on the mechanism of transport from
one medium to another.
OTHER SUBSTANCES
Trichloroethylene occurs in many commercial products, but infor-
mation on these products is not readily obtained from the manufacturers.
There are several reasons for this which include the proprietary nature
of many manufacturer's formulations, the constantly changing types and
composition of products manufactured, the alertness of manufacturers to
new information on the hazards of chemicals contained in their formula-
tions, and regulations imposed by various agencies.
Table 4.8 lists representative commercial products containing
trichloroethylene. This list appeared in 1975 and is probably out of
date in many respects. It is meant to show types of products that
might come in contact with man and is not meant to reflect negatively
on any manufacturer.
4-12
-------
Table 4.8 REPRESENTATIVE COMMERCIAL PRODUCTS CONTAINING TRICHLOROETHYLENE
Product
Composition
Substance
Percent
Manufacturer
I
M
U)
Brush Top Spot Remover2
regular Expersol 2530 (xylene)
Trichloroethylene
Perchloroethylene
Methylene Chloride
Brush Top Spot Remover , super
Carbona Cleaning Fluid
Carbona #10 Special Spot
Remover
Carbona Spray Spot Remover
Crater 2X and 5X Fluid
DuPont Dry Clean
Dux Water Repellant
Chlorinated solvents
Triethane
(1,1,1-trichloroethane)
Trichloroethylene
Perchloroethylene
Methylene Chloride
Trichloroethylene
Petroleum hydrocarbons
1,1,1-Trichloroethane
Trichloroethylene
Petroleum hydrocarbons
Trichloroethylene
1,1,1-Trichloroethane
Cab-0-Sil
Freon 12
Petroleum lubricating oil
Trichloroethylene
Pine tar
Trichloroethylene
Piccotex 120 Solution
(synthetic resin)
Wax (paraffin)
Trichloroethylene
87
10
1.5
1.5
100
50
25
10
5
44
56
10
40
50
25
Product Sales Company
Ditto
Carbona Products Co.
Ditto
Texaco, Inc.
duPont
Detrex Corp.
-------
Table 4.8 (Continued)
Product
Composition
Substance
Percent
Manufacturer
I
M
JN
Glamorene Dry Cleaner for Rugs
(Formerly Galmorene Wool Rug
Cleaner)
Glamorene Rug Cleaner
Helmac Spot Pic-Up
Aerosol spot remover
HH Tree Wound Healer
Protective seal for pruned
and damaged trees and shrubs
Instant Chimney Sweep
Aerosol spray application
Joy Solvent3
Kwik Kleen Drug Shampoo3
Dry shampoo
Lash Bath
Cleanser for false eyelashes
Chlorinated hydrocarbon
(trichloroethylene)
Petroleum distillate
Wool flour
Trichloroethylene
Ethylene dichloride
Heavy naphtha
Perchloroethylene
Methylene chloride
Trichloroethylene
Asphaltum
Petroleum oils
Phenylmercury oleate
Allantoin
Inert ingredients:
Dichlorodifluoromethane
Trichloroethylene
Methylene chloride
Trichloroethylene
Active chemicals
Propellant (Freon)
Trichloroethylene
Trichloroethylene
Naphtha
Trichloroethylene
34
41
25
Glamorene Products Corp..
Ditto
Helmac Products Corp.
Hubbard-Hall Chem. Co.
Miracle Adhesives
Joy Chemical Inc.
Royal Bond, Inc.
Revlon
-------
Table 4.8 (Continued)
Product
Composition
Substance
Percent
Manufacturer
0'Cedar Sea Spray'
Perm-A-Clor NA
Sears Air Freshener
Sears Odor Neutralizer
Spot Chief0
Surfisan Spray
Surface disinfection, preser-
vation and deodorizing
Triad Metal Cleaner
Triad Metal Polish
Trichlor - Solvent
Methylene chloride
Trichloroethylene
Cellosolve acetate
Wax
Freon propellant
Trichloroethylene
Essential oils 55.2
Perfume 10.4
Trichloroethylene 34.5
Trichloroethylene
Perchloroethylene
Solvent 310 (petroleums)
Solvent 310 (petroleum solvent)
Paradichlorobenzene
Lanolin
1,1,1-Trichloroethane
Freon 12
Chloroform
Kerosene
Camphor
Trichloroethylene
Trichloroethylene
Trichloroethylene
Trichloroethylene 100
0'Cedar
Detrex Corp.
Sears, Roebuck & Co.
White Frost, Inc.
Royal Bond, Inc.
PPG Industries,
Chemical Division
-------
Table 4.8 (Continued)
Product
Composition
Substance
Percent
Manufacturer
Tri-Clene Dry Clean
Trichloroethylene
PPG Industries, Chemical
Division
Source: Lloyd et al., 1975. The above product descriptions are not to be construed as current or
accurate since changes in product composition are being made continually by manufacturers,
a No longer marketed, but some may still be in use.
b No longer contains TCE but listed since some products may still be in use.
•e-
o^
-------
5. EXPOSURE AND BIOLOGICAL ACCUMULATION OF TRICHLOROETHYLENE IN MAN
EXPOSURE
Following is a table with an estimation of the number of workers
exposed to trichloroethylene by industry. Table 5.1 not only gives an
indication of the number of workers exposed but also indicated the diverse
industries using this solvent. It is also estimated that approximately
5,000 medical, dental, and hospital personnel are routinely exposed to
trichloroethylene as an anesthetic (Lloyd et al., 1975).
A 2-year series of studies involving cleaning operations throughout
the United States was carried out by Dow Chemical (Skory, 1974). The purpose
was to determine the extent of worker exposure during solvent vapor degreaslng
and to compare the three most commonly used chlorinated solvents: trichloro-
ethylene, methylchloroform, and perchloroethylene. Dow estimates that there
are over 25,000 chlorinated solvent vapor degreasers throughout the United
States. The studies were conducted in the worker breathing zones which were
adjacent to some 275 industrial vapor degreasing operations. The results of
this study show that trichloroethylene and perchloroethylene vapor concen-
trations measured around vapor degreasers frequently exceeded the allowable
standards for health arid safety. Peak concentrations were high enough to
present a definite health and safety hazard from anesthetic affects such as
dizziness, lack of coordination, and impaired judgment. Although the
national primary and secondary photochemical oxidant standards for chlorinated
5-1
-------
TABLE 5.1. OCCUPATIONAL EXPOSURE
Estimated Number
Industry Exposed
Agricultural Services 124
Oil and Gas Extraction 267
Ordnance 57
Food Products 2,502
Textile Mill Products 1,014
Apparel/Textile Products 858
Lumber Products 72
Furniture Mfg. 162
Paper Products Mfg. 2,240
Printing Trades 2,876
Chemical Mfg. 9,552
Petroleum Products 713
Rubber/Plastics Mfg. 4,985
Leather Products 725
Stone/Clay Products 2,685
Primary Steel Mfg. 11,672
Metal Fabrication 11,709
Machinery Mfg. 7,481
Electrical Equipment 66,727
Transportation Equipment 54,174
Instrument Mfg. 4,815
Miscellaneous Mfg. 1,516
Trucking/Warehousing 642
Air Transportation 23
Communication 5,560
Wholesale Trade 3,327
Automotive Dealer 223
Furniture Stores 597
Banking 2,391
Personal Services 583
Misc. Business Services 27,759
Auto Repair 5,246
Misc. Repair 17,198
Amusement Services 7,987
Mechanical Services 20,053
Misc. Unclassified 4,138
ESTIMATED TOTAL 282,653
Source: Lloyd et al., 1975.
5-2
-------
solvents are < 3 Ib/hr or 15 Ib/day maximum for each piece of equipment, it
is not uncommon for an idling open top (measuring 24 x 58 inches) vapor
degreaser to lose 47 Ib/day of trichloroethylene or 33 Ib/day of
methylchloroform (Archer, 1973). Judging from production figures, this
material is being lost to the atmosphere and is then replaced.
It is estimated that 2 x 10 tons of chlorinated hydrocarbons are
4
lost to the environment each year (Murray and Riley, 1973) and that 1 x 10
tons of trichloroethylene are discharged annually (Abrams et al., 1975).
It is estimated that 500 tons/day of industrial effluents are released
into the air over Los Angeles County. Of this amount, 25 tons are dry
cleaning fluids and 95 tons are degreasing solvents, that is, chlorinated
riydrocarbcns (Simmonds et al., 1974). Because trichloroethylene has been
implicated as an oxidant-producing contaminant, its use in Los Angeles County
has been restricted since 1967 (Farmber, 1973). This restriction, the famous
Rule 66, may provide a control in monitoring trichloroethylene. Since the
amount of trichloroethylene over Los Angeles County should be reduced in
relationship to other chlorinated hydrocarbons that have replaced it, the
determination of the relative amounts there and over other cities where
there no restrictions should be very informative.
Trichloroethylene is subject to certain county, state, and federal
regulations. The regulation of trichloroethylene in Los Angeles County has
already been mentioned. Also, NIOSH has recommended that the current 8-hour
time-weighted average (TWA) exposure limit for trichloroethylene of 100 ppm
be kept; but the ceiling limit of 200 ppm be reduced to 150 ppm measured
over a 15-minute period, and the current 300 ppm peak concentration be
eliminated (Anonymous, 1976).
5-3
-------
In addition, the Food and Drug Administration (FDA) has set the
following limits: 10 ppm trichloroethylene in instant decaffeinated coffee,
25 ppm trichloroethylene in decaffeinated ground coffee and 30 ppm trichloro-
ethylene in spice oleoresins (Valle-Riestra, 1974).
The basis for these regulations is various toxicological data. The
stricter regulations for trichloroethylene are based on more recent information
including studies on the carcinogenicity of trichloroethylene. The toxicology
of trichloroethylene was considered in an earlier section.
Concentrations of chlorinated hydrocarbons around a vapor degreaser
should be controlled but their presence comes as no surprise. What of
solvents in the home or living area? In a study of the air near a solvent
recovery plant in Maryland, levels of carbon tetrachloride were measured and
compared with levels of indoor air. At times, concentrations of 10 to 45 ppm
of carbon tetrachloride were measured inside a house near the plant when
levels outside were 1 ppm. The highest indoor concentration record was 90 ppm
(Bridbord et al., 1975).
What about trichloroethylene in the vicinity of manufacturing plants
or industrial areas using large quantities of these solvents? There are
no good answers at this time. There are no published reports of environmental
levels experienced in the manufacture of trichloroethylene (National Institute
for Occupational Safety and Health, 1973). The data that are available are
summarized in the section on "Occurrence of Trichloroethylene in the
Environment".
5-4
-------
BIOLOGICAL ACCUMULATION
There is little evidence to judge if trichloroethylene is accumulating
in living systems, and the opinions of scientists conflict with each other.
There is some limited data on the occurrence of trichloroethylene in
human tissue (Table 5.2). Also, dogs were exposed to relatively high
concentrations (7,000 to 20,000 ppm) of trichloroethylene and then, after
sacrificing the animals, tissure was analyzed for trichloroethylene (Table
5.3). The limited human data and the lack of exposure and medical histories
makes this data of little value in judging if trichloroethylene is accumu-
lating in man. In the care of dogs, such massive doses were given by
inhalation that judgements about accumulation in living tissue are impossible.
Doruty et al., (1975a) in a paper on hologenated hydrocarbons in
drinking water concludes that "in view of the lipophilic nature of hologenated
hydrocarbons and their occurrence in drinking water, it is not surprising
that they might be found accumulating in blood or other body tissues". There
authors present no data or references to support their contentions. They
not only lack quantitative information about levels of hologenated
hydrocarbons in blood and body tissues, but fail to produce quantification
of these substances in drinking water. Even in their full paper (Doruty
et al., 1975b) they are still talking about relative concentrations.
A Study Panel on Assessing Potential Ocean Pollutants (1975) reports
that the bioaccumulation of low-molecular weight chlorinated hydrocarbons
is quite low compared to accumulation of chlorinated pesticides in
vertebrates. This same group reports on another study in which it was
determined that bioaccumulation factor is determined by the partition
5-5
-------
TABLE 5.2. OCCURRENCE OF TRICHLOROETHYLENE IN HUMAN TISSUE
Age of
Subject
76
76
82
48
65
75
66
74
Sex Tissue
F Body fat
Kidney
Liver
Brain
F Body fat
Kidney
Liver
Brain
F Body fat
Liver
M Body fat
Liver
M Body fat
Liver
M Body fat
M Body fat
F Body fat
Concentration, p-g/kg
(wet tissue)
Trichloroethylene
32
<1
5
1
2
3
2
<1
1.4
3.2
6.4
3.5
3.4
5.2
14.1
5.8
4.6
4.9
Source: McConnell et al.-, 19751
5-6
-------
TABLE 5.3. TRICHLOROETHYLENE RECOVERED FROM TISSUE
Animal
Number
12
15
16
17
20
25
14
21
19
22
24
12
15
16
17
20
25
14
21
19
22
24
Mode of
Exposure
Acute
Acute
Acute
Acute
Acute
Acute X3
Chronic-Acute
Chronic-Acute
Chronic
Chronic
Chronic
Acute
Acute
Acute
Acute
Acute
Acute X3
Chronic-Acute
Chronic-Acute
Chronic
Chronic
Chronic
Concentrations, mg %, wet weight
Adrenal
22.4
6.24
22.5
13.8
60.6
23.1
0.94
1.06
Lung
2.8
2.2
0.92
0.92
0.40
10.4
2.0
1.3
0.53
0.26
0.13
Blood
72.5
46.0
52.7
22.3
28.4
50.0
46.1
50.6
9.6
0.13
0.25
Muscle
2.7
0.15
3.3
5.1
9.3
3.8
4.1
0.45
0.30
Brain
17.0
15.1
19.7
8.2
20.9
— —
23.6
2.7
0.22
0.22
Pancreas
3.2
9.8
6.4
14.1
43.8
8.1
16.0
2.5
<0.05
0.28
Fat
17.9
14.7
4.8
70.4
70.5
— —
22.1
""30.7
14.4
6.5
Spinal
Cord
8.8
— —
28.3
.
'
0.13
0.13
Heart
8.6
5.0
5.4
4.2
18.9
13.9
7.5
12.9
1.2
0.11
0.11
Cerebro
Spinal
Fluid
_
3.8
1.5
0.61
1.7
0.15
1.8
0.15
0.15
0.15
Kidney
1.6
8.2
5.8
3.6
3.2
17.5
21.1
5.3
1.0
0.13
0.25
Spleen
0.71
3,9
1.2
5.4
1.3
5.1
••
8.5
0.71
<0.05
0.12
Liver
27.0
9.6
38.8
10.8
9.2
49.4
20.6
9.7
3.2
0.12
0.25
Thyroid
—
2.0
6.6
•
3.9
14.1
5.8
7.4
1.1
<0.05
0.63
Source: U.S. Environmental Protection Agency, 1975.
-------
TABLE 5.4. CHLORINATED HYDROCARBONS IN MARINE ORGANISMS'
oo
Species
plankton
plankton
Nereis diversicolor
(ragworm)
Myjtilus edulis
(mussel)
Cerastcderma edule
(cockle)
Ostrea edulis
(oyster)
Buccinum undatum
(whelk)
Crepidula fornicata
(slipper limpot)
Cancer pagurus
(crab)
Carcinus maenas
(shore crab)
Eupagurus bernhardus
(hermit crab)
(Concentrations
Source
Liverpool Bay
Torbay
Mersey Estuary
Liverpool Bay
Firth of Forth
Thames Estuary
Liverpool Bay
Thames Estuary
Thames Estuary
Thames Estuary
Tees Bay
Liverpool Bay
Firth of Forth
Firth of Forth
Firth of Forth
Thames Estuary
expressed as
CC12CHC1
Invertebrates
0.05-0.4
0.0
ND
4-11.9
9
R
6-11
2
ND
9
2.6
10-12
15
12
15
5
g
parts per 10 by mass on wet tissue)
0 (*-*••- CiC/-i-A C^rirt t*w J. M i Uv* J. »
0.05-0.5 0.03-10.7 0.04-0.9
2.3 2.2
2.9 0.6
1.3-6.4 2.4-5.4
9 10 2
1 5 0.7
2-3 0-2 0.4-1
0.5 0.9 0.1
1 6 0.9
2 4 0.3
2.3 8.4
8-9 5-34 3-5
71 2
6 14 3
15 0.7 1
2 2 0,2
-------
TABLE 5.4. (Continued)
Species
.Crangon crangon
(shrimp)
Asterias rub ens
(starfish)
Solaster sp.
(sunstar)
Echinus esculentus
(sea urchin)
Enteromorpha
compressa
Ulva lactuca
Fucus vesiculosus
Fucus serratus
Fucus spiralis
Rajj clavata
(ray) flesh
liver
Pleuronectes
platessa flesh
(plaice) liver
Q
(Concentrations expressed as parts per 10 by mass on wet tissue)
Source CCljCHCl CC12CC12 CH2CC12+CC1A
Firth of Forth
Thames Estuary
Thames Estuary
Thames Estuary
Mersey Estuary
Mersey Estuary
Mersey Estuary
Mersey Estuary
Mersey Estuary
Liverpool Bay
Liverpool Bay
Liverpool Bay
Liverpool Bay
16
5
2
1
Marine algae
19-20
23
17-18
22
16
Fish
0.8-5
5-56
0.8-8
16-20
326
1 5 0.8
2 3 0.2
1 3 0.1
14-14.5 24-27
22 12
13-20 9,4-10.5
15 35
13 17
0.3-8 2-13
14-41 1,5-18
4-8 0.7-7
11-28 2-47
-------
TABLE 5.4. (Continued)
Species
Platycthys
£lesus_
(flounder)
Limanda
limanda
(dab)
Scomber
scombrus
(mackerel)
Limanda
limanda
Pleuronectes.
platessa
Y1 Solea solea
g (sole)
AspJLtrigla
cuculus
flesh
liver
flesh
liver
flesh
liver
flesh
flesh
flesh
flesh
guts
flesh
guts
Source
Liverpool Bay
Liverpool Bay
Liverpool Bay
Liverpool Bay
Liverpool Bay
Liverpool Bay
Red ear, Yorks
Thames Estuary
Thames Estuary
Thames Estuary
Thames Estuary
Thames Estuary
Thames Estuary
(Concentrations expressed
CCL2CHC1
3
2
3-5
12-21
5
8
4.6
2
3
2
11
11
6
as parts per
cci2cci2
2
1
1.5-11
15-30
1
ND
5.1
3
3
4
1
1
2
9
10 by mass
4
3
5
3
4
3
2
26
4
10
on wet tissue)
CH2CC12+CC1,
2
0.3
1.3-8
2-14
2
ND
9.9
0.3
0.9
6
1
0.6
0.3
(red gurnard)
Trachurus
trachurus flesh
(scad)
Trisopterus
luscus
(pout)
Squalus
acanthias
(spurdog)
flesh
flesh
Thames Estuary
Thames Estuary
Thames Estuary
0.3
ND
-------
TABLE 5.4. (Continued)
Species
Scomber
scombrus flesh
(mackerel)
Clupea
sprattus flesh
Gadus
morrhus flesh
(cod) air bladder
Sula bassana liver
(gannot) eggs
Phalacrocerax
aristotelis eggs
(shag)
Ale a torda
(razorbill) eggs
Rissa tridactyla
(kittiwake) eggs
Cvenus olor liver
(swan) kidney
Gallinula liver
chloropus muscle
(moorhen) eggs
Anas
platyrhvncos
(mallard) eggs
(Concentrations
Source
Torbay, Devon
Torbay , Devon
Torbay, Devon
Torbay, Devon
Sea and
Irish Sea
Irish Sea
Irish Sea
Irish Sea
North Sea
Fro d sham Marsh
(Merseyside)
(Merseyside)
(Merseyside)
(Merseyside)
(Merseyside)
expressed
CC12CHC1
2.1
3.4
0.8
freshwater
4.5-6
9-17
2.4
23-26
33
2.1
14
6
2.5
6.2-7.8
9.8-16
as parts per
ND
1.0
3^6
birds
1.5-3.2
4.5-26
1.4
19-29
25
1.9
6.4
3.1
0.7
1.3-2.5
1.9-4.5
9
10 by mass on wet tissue)
2.4
5.6
3.3
NA
1.2-1.9
17-20
39.4-41
35-43
40
4.7
2.4
1,6
1.1
14.5-21.8
4.2-24
-------
Table 5,1 (Continued)
Spefcies
Halichoerus
grypus
(grey seal)
Sorex
araneus
(common
shrew)
Source
blubber Fame Is.
liver Fame Is,
Frodsham
9
(Concentrations expressed as parts per 10 by mass
CC12CHC1 CC12CC12
Mammals
2.5-7.2 0,6-19
3-6.2 0-3.2
Marsh 2.6-7.8 1
on wet tissue)
CH2CC12+CC14
16-30
0.3-4.6
2.3-7
Notes: NA, no analysis; ND, not detectable.
a Source: Barson and McConnell, 1975.
-------
of the compound between the water and the tissues of the organism,
and further that the log of bioaccumulation is linearly related to the
log of the partition coefficient between octanol and water for some
compounds. This relationship offers a method of estimating bioaccumula-
tion. A compound such as trichloroethylene would act similarly to carbon
tetrachloride in organisms, exhibiting rapid uptake to steady state con-
centration and rapid clearance.
By far the most definitive study on bioaccumulation was carried out
by Pearson and McConnell (1975). Based on the results of an extensive
analysis of a large number of species, reproduced in Table 5.4, these
authors made some estimates of bioaccumulation in nature. They estimated
that the maximum overall increase in concentration, between sea water
and the tissues of animals at the top of food chains such as fish liver,
bird eggs, and seal blubber is less than 100-fold for a solvent like
trichloroethylene; while a higher molecular weight chlorinated compound
such as hexachlorobutadiene would have a maximum factor of 1000. They
further concluded that the pattern of extensive bioaccumulation of
marine food chains, which is postulated for chlorinated insecticides,
does not appear. In laboratory tests where organisms are maintained
for up to 3 months in apparatus similar to that used for toxicity
determinations, Pearson and McConnell (1975) have shown that bioaccumula-
tion can*occur. These results indicate the following: (1) the concen-
tration of chlorinated hydrocarbons accumulated in a tissue tends to
an asymptotic level, (2) concentrations in fatty tissues such as liver
5-1J
-------
are higher than in muscle (concentration is proportional to fat content),
and (3) when the test organism is returned to clean sea water, the
concentration of the chlorinated hydrocarbon in the tissue falls.
These researchers conclude that there is no evidence for the bio-
accumulation of C1/C2 compounds in food chains and the maximum concen-
trations found in the higher trophic levels are still only parts per
10° by mass.
Despite this strong statement, it is based on a limited set of
data, and caution should be exercised. More information is needed
before final judgment is made about the accumulation of volatile
chlorinated hydrocarbons in the tissues of animals and man.
5-14
-------
6. ENVIRONMENTAL TRENDS
To describe environmental trends, it would be necessary to have
accurate data on TCE determined over a period of time for various
media. Such data are not available for trichloroethylene. Any
environmental trends would have to be inferred from actions taken
with regard to the manufacture, use, or regulation of trichloroethylene.
There is evidence that trichloroethylene is widespread in the
environment, that it interacts with living systems, and that it appears
in air, water, food, and animal tissue. Whether it is accumulating
in the environment, in living systems, or in food cannot be judged
from the evidence available at this time.
The highest environmental concentrations of Trichloroethylene
are in close proximity to manufacturers and users. Near these sources,
levels on the order of hundreds of parts per billion are found in the
aLr and surface waters. In remote areas the levels are less than 1 ppb.
Because of the efforts of manufacturers and users to reduce the
quantity of TCE being released to the atmosphere, because of its
recognized toxicity, and because of regulations, it is likely that the
amount in that media will decline in the future. However, an offsetting
factor is the increased use of the solvent in other ways such as a
textile solvent. This will perhaps lead to the appearance of more TCE
in water and probably in the air. The net effect cannot be determined
without more extensive monitoring data.
Perhaps such efforts as the National Organics Reconnaissance Survey
will ultimately provide sufficient information to establish a trend for
environmental levels of trichloroethylene.
6-1
-------
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