ENVIRONMENTAL PROTECTION AGEINC
OFFICE OF ENFORCEMENT
Reconnaissance
v/ron mental Lc v of Nitrosan
in the Central United States
TIONAL ENFORCEMENT INVESTIGATIONS CENTE
DENVER. COLORADO
JANUARY 1977
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ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF ENFORCEMENT
EPA-330/1-77-001
RECONNAISSANCE OF ENVIRONMENTAL LEVELS
OF NITROSAMINES IN THE CENTRAL UNITED STATES
January 1977
National Enforcement Investigations Center
Denver, Colorado
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TABLE OF CONTENTS
Page
• . . . • 1
• . S I S
• . . . . 6
: : : : : 12
17
18
• . . . . 28
• . . . . 28
• . . . . 29
• . . . . 34
• . . . . 36
37
• . . I S I S
• I • I I S S
• S I I S I •
S S S • S S S
TABLES
1 . Results of Amine (DMA) and Nitrosamine (DMN)
Analyses at E. I. DuPont
2. Results of Nitrosamine and NO, Analysis in . . . . • . . . • • 17
Harris County - August 19, 1976
INTRODUCTION.
FIELDSTUDY —PHASE I . . • . . . • . . . . . . .
Dow Chemical USA . . . . . . • . . .
Union Carbide Corporation
E. I. DuPontDeNemours . . . . . . . .
Houston, Texas .
FIELDSTUDY-PHASEII .
DISCUSSION • . . . . . . . . . . . . . . • • . • . •
Phase I • • •
Phase II
SUMMARY AND CONCLUSIONS . . ... ... ...
REFERENCES • • • • •
APPENDIX A - Analytical Procedures and Quality Assurance
FIGURES
1. Dow Plant “A’ . . . . . . • • • .
2. Freeport. Texas
3. Vicinity of Union Carbide Amine Plant
4. Union Carbide and Vicinity . . . .
5. E. I. DuPont and Vicinity . . . . .
• S I S S
• I I S I
7
8
10
11
14
. 15
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TABLES (Continued)
Page
3. Results of Phase II Air Sampling — First • • 20
Part - 1976
4. Results of Phase II Wastewater Sampling . . . . . . . . . . . 23
First Part - 1976
5. Results of Phase II Air Sampling — Second . . . . . . . . . . 24
Part - 1976
6. Results of Phase II Wastewater Sampling . . . . . . . . . . . 27
Second Part - 1976
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INTRODUCTION
The toxic and carcinogenic properties of nitrosamine compounds have
been recognized for many years. Of more than 100 of these compounds
synthesized, over 70 percent have been shown to be carcinogenic to some
animal species. In laboratory tests, this class of compounds has produced
cancer in all animal species tested. To date, however, these compounds
have not been demonstrated to cause similar effects in humans due in
part to the low exposure levels, the small number of people exposed,
and the impact of other environmental and physiological unknowns. It
is likely that continued interest in this class of compounds will
stimulate the research needed to demonstrate an effect in humans. A
number of co nprehensive reports have been written recently assessing
the technical and scientific information currently available on
nitrosamines (1-5).
Nitrosamines are a class of organic compounds containing the N—N0
linkage and having the general structure
N-N=0
Since R and R’ can represent alkyl, aryl or cyclic groups, the nitrosamine
compounds have widely varying chemical, physical and toxicological
properties.
Early studies of nitrosamines were directed toward the evaluation of
these compounds in foods and biological specimens, since the compound has
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2
been found in a number of products including wheat grain, unprocessed
milk and cheese, tobacco and smoked meats. In particular, attention was
directed to the possibility of in vivo or secondary formation of nitros-
amines due to the ubiquitous nature of their precursors.
Only two N-nitroso compounds have been produced in significant
quantities for industrial or manufacturing purposes. Diphenylnitrosamine
(N—nitrosodiphenylamine) is produced by the rubber industry for use as
a retardant in various curing processes. This chemical has not proved
carcinogenic to test animals. The other compound, dimethylnitrosamine
(N—nitroso dimethylamine) is an intermediate in the production of the
rocket fuel unsymmetrical dimethyihydrazine (UDMH) and has shown
carcinogenicity.
Until recently, little interest was shown in environmental nitrosamine
levels. However, with the development of highly sensitive and relatively
specific analytical techniques, the presence of these compounds was measured
at a number of locations where amines and/or N-nitroso compounds might be
expected. These results, along with an assessment of the environmental
and health impact of nitroso compounds, have be n reported elsewhere (1-4).
Following an EPA-funded study (6, 7) of the only known primary source
of a carcinogenic nitrosamine (the FMC Corporation in Baltimore, Maryland)
attention was turned to precursor sources; i.e., mainly sources of secondary
amines. These included sources that might manufacture, use or discharge
these compounds. Sources of primary and tertiary amines are of less
interest if nitrosation is considered to occur via reaction with nitrous
acid in the environment. Unlike the secondary amines which can form
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3
nitrosamines, the primary aliphatic and aromatic amines yield other
products and only a few tertiary amines form nitrosamines. If other
reaction mechanisms are hypothesized to yield nitrosamines, e.g., with
metallic compounds, the number of possible precursors would be expanded.
However, there is no indication of measurable levels of these nitroso
compounds in environmental samples to date. In fact, only dimethylnitros-
amine (DMN) and diethylnitrosamine (DEN) and possibly several others
observed but not identified have been reported. These results are
discussed elsewhere (1, 2).
The health effects of the ambient levels reported to date are still
unknown. However, the presence of the compounds in the environment
required that the Agency evaluate the sources and circumstances contributing
to the levels observed, concurrent with a determination of their possible
public health implications. To begin this task the Office of Air
Quality Planning and Standards (OAQPS), and later the Pesticide and
Toxic Substances Enforcement Division (PTSED) requested that the NEIC
collect and analyze a variety of environmental samples. The sampling
program was established to aid in determining the necessity for the
development of a control strategy for this class of compounds.
Objectives of the program were as follows:
1. To locate possible sources of direct emission of nitrosamines
into the environment.
2. To assess secondary formation processes by measuring levels
of nitrosamines in the vicinity of plants producing, processing,
or releasing amines to the environment.
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3. To measure ambient levels of nitrosamines in urban and
rural areas.
4. To measure nitrosamine levels on, and transverse to, selected
highways subject to diesel engine exhaust.
4
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5
FIELD STUDY - PHASE 1
The first phase of the study was conducted during August 1976 near
Houston, Texas, in the vicinity of three chemical plants known to be amine
producers or users. These were Dow Chemical USA at Freeport, E. I.
DuPont DeNemours and Company at LaPorte, and Union Carbide Corporation
at Texas City. The study arose through a coordinated effort by officials
of State, County and City governments, representatives of the three
industries and of EPA’s Office of Air Quality Planning and Standards
(OAQPS) and Environmental Sciences Research Laboratory (ESRL).
An NEIC mobile laboratory was set up first at Dow Chemical and then
at DuPont to provide analytical support for the determination of
nitrosamine,NO and wind direction information. The laboratory was
outfitted with special lighting to reduce ultraviolet radiation and
contained a Thermo Electron Corporation thermal energy analyzer for
nitrosamine analysis. The analyzer was on loan to EPA through the
courtesy of the DHEW National Cancer Institute.
Air samples were collected in aluminum foil,-covered impingers
containing 60 ml of iN KOH. Flow through the impingers was regulated to
about 2 1/mm with a critical orifice. Air samples were collected
for about 90 minutes to obtain the necessary analyzer sensitivity.
Water samples were collected in amber glass bottles having teflon-lined
caps. Imediately following collection, samples were taken to the
mobile laboratory for analysis. Analytical procedures are presented in
Appendix A. Using these procedures, the detection limits for DMN
were about 20 ng/m 3 in air and 20 ng/l in water. The detection limits
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6
for other N-nitroso compounds reported here increase almost in direct
proportion to molecular weight.
Dow Chemical USA
Dow Chemical USA at Freeport, Texas, was producing ethylenediamine
(EDA), diethylenetriamine (DETA), piperazine, aminoethylpiperazine (AEP),
tetraethylenetriamine (TETA), tetraethylenepentamine (TEPA), pentaethylene-
hexamine (PEHA), hexaethylenehexamine (HEHA) and higher amines at the
time of the survey (August 10—11, 1976). Temperatures ranged between
31-33°C (87—92°F) during the sampling periods, and winds were south-
easterly as usual for that time of the year.
Each day a set of air samples was collected around the amine
producing block and another set downwind of the Dow Plant “A° and
transverse to the wind. Each set included one upwind and three downwind
samples. The location of sampling stations around the amine production
block (A-38) is shown in Figure 1 and the location of the off-plant
stations are shown in Figure 2. No nitrosamine compounds were detected in
any of these sampl es.
in addition to the above, a water sample was collected at the main
amine plant ditch and at the scrubber stream from the thermal oxidizer.
These streams joined before flowing from the east side of the amine area.
No nitrosamines were detected in either of these samples.
Union Carbide Corporation
Sampling at the Union Carbide Corporation at Texas City (August 16,
17, 19) was conducted while the mobile laboratory was set up at the
DuPont plant. Impingers were prepared in the laboratory at LaPorte,
taken to Texas City to collect the necessary samples, and then returned to
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I
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Figure 1. Dow Plant “A”
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— _- — ,j _•_
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Figure 2 Fre.port, Texas
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9
the laboratory for analysis. This avoided the necessity for moving the
laboratory a third time at a considerable savings in time and effort.
At the time of the survey the Union Carbide Corporation was
producing EDA, TEA and triethylenetetranine and polyamines.
Four air sampling sets were collect’id at Union Carbide Corporation.
Two sets, one morning and one afternoon, were collected around the amine
production facility (Building 51). Sampling locations are shown in
Figure 3. During the morning set (August 19) winds were variable so
the impingers were spaced SE, SW, N and NW of the plant to obtain
uniform coverage. At the time of the afternoon series (August 16),
winds were southeasterly so one sample was located upwind (SE) and the
others downwind (NE, NW and NNW) of the facility. The third set of samples
(August 16) was collected on the plant perimeter, again with one sample upwind
and three downwind [ Figure 4]. This set was started about 8 p.m. and
therefore would represent nighttime conditions when ultraviolet radiation
would not be a factor. The last series of air samples (August 19) was
collected around the Off-Plant Disposal Area (OPDA) lagoons [ Figure 4].
Residence time in this system was estimated by the company at 120 days.
The wastes then flowed to lagoons operated by the Gulf Coast Waste
Disposal Authority (GCWDA) for additional treatment.
Two wastewater samples were collected from the OPDA lagoons during
the survey, one each of the influent and of the effluent. While nitros—
amines were not found in any of the air samples, both wastewater samples
showed the presence of DMN. The influent sample contained 1.2 pg/i
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and the effluent sample 0.4 jig/i. These reported values do not reflect
the extraction and concentration efficiencies of the analysis which is
estimated at about 32 percent. The OPDA lagoons have now been drained
as Union Carbide is reclaiming this land. The wastes now go directly
to the GCWDA for processing.
E. I. DuPont DeNemours and Company
Sampling in the vicinity of this plant was much more extensive than
at the other two. Since DuPont was bordered on the south and east by
Highways 225 and 146 and was known to produce and use amines in their
processing, this proved an excellent opportunity to determine whether
amines reacted in the atmosphere with oxides of nitrogen (N0 ) to produce
measurable amounts of N-nitroso compounds. With winds generally south-
easterly it was anticipated that automobile generated N0 would be
transported over the plant providing an opportunity to react with
atmospheric amines.
During the sampling period (August 13-18) the company was producing
dimethylamine (DMA) and mononiethylamine, filling cylinders of trimethyl-
amine, and using DMA to produce a urea herbicide (Diuron), a uracyl
herbicide (Velpar) and a carbaruate fungicide (Thiram). On August 16,
the amine production unit began to leak, terminating production for about
three weeks. The company indicated that opening the unit for repairs
might increase amine levels in air and water so sampling continued.
To determine an average NO level during the sampling period, NEIC
constructed teflon-lined containers to sample concurrently with the
impingers. The vacuum pump pulling samples through the impinger was
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13
also evacuating the container surrounding the teflon liner. This
expanded the liner, drawing in the air sample. Since the system exposed to
the atmosphere was completely teflon, it was felt that the NO collected
would be representative of average ambient levels. Measurement of these
samples was unsuccessful when neither of the two NO analyzers in the mobile
laboratory would operate. However, independent of this effort, personnel
from the Harris County Pollution Control Department collected NO 2 samples
using impingers and the Texas Air Control Board “Modified Christie
Technique” for analysis. Results of analyses of samples collected at
E. I. DuPont during the period of interest was made available to NEIC.
Concurrent with the NEIC nitrosamine sampling, personnel from
E. I. DuPont collected a similar sample, as well as a sample for
djmethylamin analysis. The latter was analyzed gas chromatographically
in the company laboratories and results were provided to the survey team
when requested. This analytical support, as well as electrical power
and services for the mobile laboratory, proved invaluable.
With a southerly wind it was necessary to sample in Upper San Jacinto
Bay and the Houston Ship Channel. This was accomplished with support from
the Houston Office of the Texas Air Control Board which provided a
boat and two engineers for assistance.
Six sampling runs were made in and around the DuPont facility. Two
were made around the amine production unit, two were downwind and transverse
to the plant in Upper San Jacinto Bay and the Houston Ship Channel, and
two were on downwind trajectories from the plant. Because of northerly
winds, the downwind trajectories were south of the plant. Off-plant
sampling points are shown in Figure 5 and results presented in Table 1.
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TABLE 1
Results of Amine (DMA) and Nitrosamine (DMN) Analyses at E. I. DuPont
5 8/18 Map
Map
Map
Map
location 12
location 13
location 14
location 15
N.D.
N .D.
5.9
16.5
N.D.
4.8
N.D.
N.D.
N.D.
100.0
N.D.
64.5
N.D.
N .0.
N .D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
ND.
1630-1800
1650-1803
1700-1 816
1705-1825
1130-1300
1147-1 324
1141 -1312
1135-1 305
081 3-0950
0758-0944
0751 —0937
0746-0929
E
a N.D. — not detectable (DMN detection limit — 7
ng/m )
A blown fuse caused vacuum pump to stop sampling. In addition,
was slightly later than normal retention time for DMN.
this substance is unconfirmed since peak
-
U,
Run Date
1 8/13 SE
NE
NW
W
Sample Location
corner of
corner of
of amine
of amine
amine
amine
plant
plant
plant block
plant block
DMA
g/m 3
5.9
3.0
12.0
9.1
DMNC
ng/m 3
N.D.a
N .0.
Sampling Time
0926-
0914-1 052
091 7-1100
2 8/13 At mobile lab SW of plant
Map location 006
Map location 007
Map location 008
3 8/14 At mobile lab SW of plant
Map location 009
Map location 010
Map location 011
4 8/15 SE
NE
NW
W
corner of
corner of
of amine
of amine
amine
amine
plant
plant
plant block
plant block
Wind Direction
SW
SSW
SW-SE
S
N
21.9
9.8
N .D.
N.D.
7.3
N.D.
N.D.
081 3-1002
0819-1004
0805-0950
0810-0957
6 8/18 Map
location
016
N.D.
N.D.
1605-1738
Map
location
017
9.7
N.D.
1556—1730
Map
location
018
18.7
N.D.
1549-1718
Map
location
019
N.D.
N.D.
1541-1712
C Uncorrected for collection and extraction efficiency (78 percent).
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16
The data indicate only two occasions when DMN was observed, although
DMA was detected in 13 samples. Both positive samples were found at the
same location, in the immediate vicinity of the amine production facility.
Positive values of DMA tended to indicate that samplers were being set down-
wind of the plant. The absence of DMA at the mobile laboratory when it
was upwind of the plant tended to confirm this situation. However, on
August 18, 1976, when the impingers were being set out for Run 6, the wind
was from due north, indicating that the trajectory should be sampled as
indicated by location 016-019 [ Figure 5]. After the samplers were in place
the winds shifted 900, blowing toward the west and maintained that
direction throughout the 90-minute sampling period. The data [ Table 1]
however show measurable concentrations of DMA at two stations. This would
indicate other sources of DMA in the vicinity. In an area as heavily
industrialized as the Houston Ship Channel, this is to be expected.
Data provided by Harris County indicate on August 13 that the NO 2
level during Run No. 1 was •c6pg/m 3 . An hour before Run No. 2 they report
31 pg/rn 3 NO 2 and the same value at the time Run No. 2 began. On August 18
two hours before Run No. 6 began, while the wind was still northerly, they
report 19 j ig/rn 3 NO 2 and an hour later report 27 pg/m 3 .
Two wastewater samples were taken at the plant, one of the treatment
plant influent and one of the effluent to San Jacinto Bay. The plant
includes activated sludge ponds followed by clarifiers. The effluent
is diluted 3 to 4 times with non-contact cooling water before being
discharged to the Bay. The diluted effluent was sampled. Both samples were
found to contain DMN and diethylnitrosamine (DEN). The influent contained
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17
5,4 pg/i DEN and 10 pg/i DMN. The treated and diluted effluent
contained 0.3 pg/i DEN and 0.7 pg/i DMN. Assuming that these grab samples
are representative, the treatment facility is removing abQut 75 percent of
the N-nitroso compounds, at least for this single sample. Reduction could
be attributable to microbial activity, photolysis and/or evaporation.
Houston, Texas
At the request of the Harris County Pollution Control Department
and the City of Houston Health Department, a single traverse was sampled
across Houston. Impingers were set at four locations. At two of these
locations NO 2 samples were also collected by Harris County personnel
Results are shown in Table 2. While NO 2 was found at both locations
sampled, nitrosamines were not present in measurable concentrations.
TABLE 2
Results of Nitrosamine and NO, Analysis
in Harris County — August T9, 1976
NO
Location DMN
Harris County Building, Pasadena N.D.b
C.H.A.M.P.S. Trailer, 9525 Clinton Dr. N.D. 39
Polk and Crawford Street N.D.
City Health Department, MacGregor Dr. N.D. 66 a
a Average of two samples
b Not detectable
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18
FIELD STUDY - PHASE II
The second phase of the study was designed to sample a wide variety
of possible amine and/or nitrosamine sources and to measure ambient levels
in urban and rural areas. Samples were collected at petroleum refineries,
coke batteries, sewage treatment plants, rendering plants and chemical
and pesticide producing facilities among others. Because of the mobility
required for the task, the thermal energy analyzer remained in Denver
and a van was outfitted to contain all the sampling equipment necessary
to permit air sampling while moving along the highway or at locations
where power was not available. Air and water samples were collected
as before; however, these were cooled in an ice chest before being returned
to Denver.
Scheduling requirements made it necessary for this phase of the study
to be completed in two parts. The first part included a sampling program
beginning at NEIC Denver and following Interstate 70 (with several side
trips) through Kansas, Missouri, Illinois, and Indiana. After the last
samples were obtained in Terre Haute, Indiana, the van was stored in
Indianapolis for several weeks while the air and water samples were
returned to Denver for analysis.
Several weeks later the second part of the program was begun with
sampling at Lafayette, Indiana, north to Chicago and then back to Denver
along Interstate 80 through Iowa and Nebraska. As before, the samples
were cooled in ice chests until ready for analysis at IIEIC. Each
part of Phase II sampling required slightly over a week.
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19
In addition to the air and water samples collected for analysis
in the NEIC laboratories, occasional air samples were collected on
prefiltered Tenax resin columns for subsequent analysis by gas chromatography
and mass spectroscopy (GC/MS) at the Research Triangle Institute in North
Carolina. The GC/MS analyses were funded through an EPA Office of
Research and Development contract. These samples were collected simul-
taneously with the impinger samples to provide quality assurance for
laboratory analysis.
Analytical results of both parts of Phase II sampling follow.
Tables 3 and 4 present the results of air and water analyses for the
first half of the program, and Tables 5 and 6 the results of the second
part. These data are presented in chronological order and are not
corrected for extraction or concentration efficiencies which were
indicated earlier to be about 32 percent for DMN and higher for
heavier compounds [ see Appendix A]. Analysis of these data and possible
anomalies that may exist are included in the Discussion.
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TABLE 3
Results of Phase U Air Samplinga_ First Part — 1976
DMN Temp. Weather
Date Sample Location ngfsanip le ngfni Sampling Time DC Wind Speed - mp
Nov. 11 Along 1—70 Colby, KS — Ogallah, KS 10 46 1107—1232 0
0.25 mi SW of 1—70 on State 232 at Wilson, KS 13 57 1425-1555 1 Variable 6 - 8
Centerline of 1-70 on State 232 overpass at Wilson, KS 13 55 1427-1604
0.15 mi NE of 1—70 on State 232 at Wilson, KS 10 44 1429-1606
Nov. 12 Missouri Chemical Corporation, St. Joseph, MO
pesticide packaging plant
SE corner downwind of plant 9 42 1218—1353 1 N 5 — 10
S side of plant 11 57 1231—1403
N side of plant, upwind 10 55 1242—1411
Amchem Corporation, St. Joseph, MO
pesticide packaging plant
N side of plant, upwind 9 48 1519—1647 1 N 5 — 10
SE side of plant, downwind 14 71 1527—1700
S side of plant 18 95 1537—1705
Nov. 13 Phillips Petroleum, Kansas City Refinery, KS
petroleum refinery
*SE corner of plant on levee 9 51 0847—1009 -7.5 Calm
SW of plant on Fairfax Road 10 57 09011020
NW of plant at Fairfax Road and Quindaro Boulevard 11 69 0906—1025
Chemagro, Kansas City, MO
chemical plant
SE corner on levee 6 31 1124—1256 0 Calm
- *SSW of plant on levee —
W of plant at Guard House 7 35 1142—1315
Big Blue River SIP, Kansas City, MO
E of plant at grit chamber 8 46 1326—1450 0 Calm
S of plant at effluent structure 17 92 1330—1457
NW corner of plant N.D.b N.D. 1336—1509
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TABLE 3 (Continued)
Date Sample Location
Nov. 13 Along 1-70 from MO 291 to MO 41 & 135
Nov. 14 0.2 mi S of 1-70 on US 54, MO
Centerline of 1-70 on US 54 overpass, MO
0.2 mi N of 1-70 on US 54, MO
Lemay STP, Lemay, MO
SW corner of primary clarifiers
Eside of grit chamber building
N side of plant
Nov. 15 Monsanto Chemical Corporation - St. Louis, MO
N side of plant
SE corner of plant
*5W side of plant
Sampling Time
National By
rendering
NW corner
SW corner
SE corner
Products, Inc., St. Louis, MO
plant
of plant
of plant
of plant
• DMN
ng/sample ng/m 1
9 48
11 55
9. 45
8 42
6 32
52
N.D. M.D.
12 70
31
6 30
M.D. N.D.
N.D. N.D.
N.D. N.D .
8 45
14 81
9 52
20 102
M.D. N.D.
9 49
Great Lakes Carbon Corporations St. Louis, MO
Missouri Coke and Chemical Division
coke producers
N side of plant at main gate
SW corner of plant
*SE corner of plant
Temp. Weather
______________ °C Wind Speed-n
1548-1714 2 Calm
0834-1000 2 Calm
0837—1005
0847-1012
1301-1425 8 Calm
1318-1 434
1325—1441
0839-0953 6
0848-1004
0903—1033
1128—1 253
1135—1258
1142—1302
1353—1511 9.5
1401-1517
1413-1 530
1707—1832 6 Variable 0 — 3
1715-1 842
1727—1851
Granite
steel
WSw
NW of
SE of
City Steel Corporation, Granite City, Ill.
mill
f coke ovens on Illinois 162
coke ovens and by-product area on Illinois 162
coke ovens in coal preparation area
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TABLE 3 (Continued)
DMN Temp. Weather
Date Sample Location ngfsaniple ng/m Sampling Time °C Wind Speed —
Nov. 16 Shell Oil Company, Wood River, Illinois
petroleum refinery
SE of production area at S. gate 6 25 0854-1031 10 NW 5 — 1
W side of plant, N. of main entrance on Illinois 111 14 58 0902-1048
NE of plant on Illinois 143 4 19 0922-1102
Along 1-70 from Illinois 4 to Illinois 49 5 21 1150-1339
Indiana Gas and Chemical Corporation, Terre Haute, md.
coke producer
N side of plant on Hulman Street 12 52 1551 -1730 10 Calm
*E side of plant near switching yard. 11 52 1605-1 739
W side 0 f plant on 13th Street 7 28 1615-1756
Nov. 17 IMC Corporation, Terre Haute, Indiana
chemical plant, amine producer
SW corner of plant on Wabash River 15 72 1032—1207 .12
*NW corner of plant 22 100 1042-1220
SE corner of plant at Research Center 18 96 1049-1214
SW corner of plant on First Street . 9 44 1101 —1230
* Samples collected concurrently for analysis by Research Triangle Institute
a Uncorrected for collection and extraction efficiency (65 percent).
b N.D. - Not detectable . (DMN detection limit - 20 ng/m 3 )
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TABLE 4
Results of Phase II Wastewater Sampling — First Part - 1976
DMN DEN DPN PBN DBN
Date Sample Location ugh ugh ig/l ig/1 ugh
November 12 Phillips Petroleum, Kansas City Refinery, KS N.D. fLO. N.D.
Outfall 001 to Missouri River
Chemagro, Kansas City, MO 0.32 1.5
Outfall 001 to Blue River
Arnchem Corporation, St. Joseph, MO 3.3
Ag line wastewater to city sewer
November 13 Phillips Petroleum, Kansas City Refinery, KS 0.07
Resample of Outfall 001
Big Blue River SIP, Kansas City, MO Effluent 0.08 0.07
November 14 Lemay SIP, Lemay, MO N.D.
Primary effluent to Mississippi River
November 15 Monsanto Chemical Corporation - St. Louis, MO N.D.
Clean acid sewer to Missouri River
Great Lakes Carbon Corporation, St. Louis, MO N.D.
Outfall 001 to Mississippi River
Granite City Steel Corporation, Granite City, Ill. N .D.
Outfall 001 to Horseshoe Lake
November 16 Shell Oil Company, Wood River, Ill. N.D.
Composite effluent to Mississippi River
Indiana Gas and Chemical Corp., Terre Haute, md. 1.7 0.24 0.24 0.48 0.82 , ,
Effluent to city sewer
November 17 IMC Corp., Terre Haute, md. 0.11 0.29
Outfall 003, non- contact cooling water, DMA
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TABLE 5
Results of Phase II Air sampiingd_ Second Part — 1976
DMN Mlsc. CompourrdS Temp. Weather
Date Sample Location ngiiimple 7 n 3 n9/sample ng/& mpling Time °C Wind Speed-mph
Nov. 29 Eli Lilly Corporation, Lafayette, md.
—pharmaceutical and pesticide manufacturing
NW corner of pesticide production area, upwind 5 16 1240—1458 —10
SW corner of pesticide production area 9 31 4 1249-1 505
*SE corner of pesticide production area, downwind 4 15 16 58 a 1309—1510
6 22 b
NE corner of pesticide production area 7 27 18 698 1316—1516
Nov. 29 Lafayette SIP, Lafayette, md.
E of plant at plant office building 5 25 1730-1900 —10 ENE 7
W of plant at trickling filters 8 41 1741 -1912
Middle of plant near digesters 4 21 1752—1916
Junction Haisted Avenue (Rt. 1) and Dixie Highway
Chicago Heights, Illinois Industrial Area
Nov. 30 Daylight Sample (0849) 5 23 0849-1035
Dec. 1 Night Sample (1805) 19 94 16 798 1805—1933 —
SW corner 103rd and Cottage Grove
Chicago (South Side), Illinois Industrial Area
Nov. 30 Daylight Sample (1113) 4 13 1113—1328
Dec. 1 Night Sample (1732) 13 64 1732—1900 —g
Nov. 30 Rooftop 1817 W. Pershing Road (EPA Lab)
Chicago (Mid-town), Illinois Industrial Area
Daylight Sample (1226) N.D. N.D. 1226—1435
Nov. 30 General Motors, McCook, Illinois
Electromotive Division
West side of plant, upwind 5 24 18 87 a 1324-1654
24 120 b
23
North Side of plant, downwind N.D. N.D. 1554—1726
cr iith Sid n olant 4 22 1616—1738
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TABLE 5 (Continued)
DMN Misc. Compounds Tern W athe
mp1e Location ngT ärnp le nglm 3 i Tsample ng/w 3 sampling Time °C Wind Speed-mph
Business Rt. 20, Elgin, Illinois
NW Chicago Light Industry Area
Nov. 30 Night Sample (1938) 15 80 1938-2108
Dec. 1 Black Leaf Products, Elgin, Illinois
Pesticide packaging plant
SW corner downwind of plant 19 90 19 90 a 0829-1000 -9 Variable 0 - 10
12
13 62c
NW corner of plant 24 180 0903 1032
SE corner of plant 17 82 0909-1 040
Dec. 1 Union Oil Chicago Refinery, Lemont, Illinois
petroleum refinery
West plant boundary at water influent, upwind 16 58 .1241 -1440 -9 WSW 5 — 10
NE corner of plant at North gate 16 61 1256-1450
*SE corner of plant, downwind 20 130 1315-1500
Dec. 2 Mobil Oil Refinery, Joliet, Illinois
petroleum refinery
SW corner of plant 24 11Q 18 85 a 0935—1105 —9 N 8 — 10
*South side of plant, downwind 17 80 0953—1124
North side of plant, upwind 15 65 1003—1142
Dec. 2 Monsanto Chemical , Muscatine, IA
chemical plant
East side of plant 12 58 1637—1807 —16 NNW 2 — 5
corner of plant, downwind N.D. M.D. 1655-1820
West side of plant 4 21 1700-1825
Dec. 3 National By-products, Des Moines, IA
rendering plant
NW corner of plant 4 16 1119—1318 -6 S 0 - 5
*NE corner of plant, downwind N.D. M.D. 1133—1326
South of plant downwind of cooling towers N.D. M.D. 1141-1338
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TABLE 5 (Continued)
DMN Misc. Compounds Temp. Weather
Date Sample Location ngf sample ñ 7ni 3 ng/saniple ng/T) 3 Sampling Time °C Wind Speed—mp
Dec. 4 Des Moines SIP, Des Moines, IA
NW corner of plant at administration building 20 98 0841 —1018 —6 Calm
Middle of plant at pumphouse 21 100 0858—1029
East end of plant at intermediate clarifiers 19 91 0909-1039
Dec. 4 Along 1-80 Des Moines, IA to Avoca, IA 16 78 1122-1259
Dec. 6 Imperial Chemical , Shenandoah, IA
pesticide formulation plant
*SE corner of plant, downwind 16 74 0 05-l044 -7 UNE 10
North side of plant, upwind 15 63 0911-1058
Dec. 6 Along 1-80 York, Neb. to Kearney, Neb. 13 66 1455-1630 -12
Dec. 7 Along 1—76 Colorado State Line to Brush, Co1o. 7 31 0800-0945 4 NNE 12 —
M.D. Not detectable . (DMN detection limit — 20 ng/m 3 )
* Concurrent samples collected for analysis by Research Triangle Institute.
a Dipropylnitrosarnine
b Dibutylnitrosarnine
c Nitrosomorphol me
d Uncorrected for collection and extraction effi.c ency C65 percent)
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TABLE 6
Results of Phase II Wastewater Sampling — Second Part - 1976
DMN DPN EBN ‘NPD*
Date Sample Location iig/l pg/i pg/i pg/i
Nov. 29 Eli Lilly Corporation, Lafayette, md.
001 Outfall to Wabash River 0.03 0.12 0.04 N.D.
002 Outfall to Wabash River 0.11 2.8 2.3 N.D.
Nov. 29 Lafayette SIP, Lafayette, md.
Outfall to Wabash River N.D. N.D. N.D. N.D.
Dec. 1 Union Oil Chicago Refinery, Lemont, Ill.
Outfall 001 to Chicago Sanitary and Ship Canal N.D. N.D. N.D. N.D.
Dec. 2 Monsanto Chemical , Muscatine, IA
001 Effluent to Mississippi River N.D. N.D. N.D. N.D.
Taken from 24-hour composite sampler
Dec. 3 National By Products, Des Moines, IA
Effluent to Des Moines SIP 0.02 r1.D. N.D. 0.20
Dec. 4 Des Moines SIP, Des Moines, IA
Outfall to Des Moines River N.D. N.D. N.D. N.D.
*NPD — nitrosopyrrolidine
F ’,
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DISCUSSION
Phase I
The air sampling results obtained in the Houston area indicated
that either nitrosamines were not emitted from the plants, or that once
in the atmosphere these compounds decomposed rapidly. In the case of
the air and water samples collected at Dow Chemical USA, the absence
of positive results in either medium provided no information of the
validity of either possibility.
At Union Carbide where results from air samples were negative, both
wastewater samples were positive for DMN and of the same magnitude found
elsewhere (6). On the basis of this limited data, effects of passage
through the lagoon system were minimal when considering that the reduction
occurred over a detention time estimated at 120 days. Even if reduction
resulted from evaporation, the small amount lost at a very slow rate
would not have been detected.
Results obtained at DuPont did indicate that DMN may occasionally
be emitted in the imediate vicinity of the processing units, however,
none was ever detected off plant property. These data also showed little
evidence for amines and oxides of nitrogen combining to produce N-nitroso
compounds under the conditions present in the study area. Both high
temperatures (>29°C) and summer sunlight probably affected the results.
Losses from the DuPont wastewater treatment system, as indicated
by reduction in N-.nitroso levels, may have introduced both DMN and
DEN into the air. However, these compounds were never detected, even
though several air samp es were collected at the mobile laboratory in
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the immediate vicinity of the wastewater treatment facilities. While the
DMN level here was in the range of those reported (6-8 at the DuPont
plant in Belle, West Virginia, (2.3 - 8.6 iig/l), the DEN had not been
detected earlier in the Belle effluent.
Phase II
In direct contrast to the results obtained in Phase I, the Phase II
air sampling produced mainly positive results. During the first part
of this sampling program the only negative results were those samples
collected in the vicinity of the National By Products rendering plant
in St. Louis. Little difference was seen across highways, around steel
mills, or at pesticide formulating facilities. The uniformity of these
positive results, where little had been anticipated, required a close
scrutiny of all aspects of sample collection and analytical procedures
for the purpose of assuring the quality of the data.
A careful review of sample handling procedures, supported by
laboratory experimentation, pointed out the possibility that DMN
standards in sealed vials were able to contaminate the atmosphere of the
laboratory refrigerator. With standards containing mg/l concentrations,
very little loss was necessary to produce concentrations in the
refrigerator measurable with instruments detecting picogram quantities.
Thus, when small quantities of methylene chloride evaporated, even at
refrigerator temperatures of —4°C (25°F) DMN was apparently codistilled,
diffusing into the refrigerator. When the first series of samples were
returned to the laboratory for processing they were extracted, placed in
glass bottles and sealed with a teflon-lined cap to await further
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30
processing. It is hypothesized that as these samples cooled and the
vapor condensed, reducing pressure in the containers, vapor in the
refrigerator may have been drawn into each of them contaminating the sample.
Reviewing the data in Table 3, it is possible that samples containing
less than about 10 ng DMN were, in fact, only showing effects of this
contamination and only quantities above this level should be considered
as positive. Thus, the mass and concentration might be reduced proportion-
ately, or the results as presented when corrected for correction and
extraction efficiencies considered as maximum values.
Since the first set of water samples collected during Phase II were
processed in a similar manner, these might be expected to show similar
effects. However, since the quantity of methylene chloride used in the
extraction is’larger (100 ml vs 24 ml) the head space is reduced and potential
contamination minimized. Thus a number of samples in Table 4 showed no
detectable levels of N—nitroso compounds. However, several samples did
show compounds eluting at times corresponding to DPN, PBN and DBN which
have not been reported elsewhere and would not have been possible
contaminants. In fact, the effluent sample from Indiana Gas and Chemical
Corporation showed peaks corresponding to five different N-nitroso compounds.
Samples collected during the second part of Phase II also showed levels
significantly higher than anticipated at some locations, even though
precautions were taken to avoid the contamination suspected earlier.
Continued checking showed that one bottle of distilled water contained
250 ng/l of a compound having the same elution time as DMN. While the
reagents and distilled water originally carried from NEIC showed no
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31
contamination, one container of distilled water was refilled at the
Shell Oil laboratories in Wood River. The laboratory generates distilled
water by passing steam condensate through ion exchange resin. Both
ion exchange resins and steam system additives to prevent scaling may
be sources of amines and/or nitrosamines. A second set of distilled water
samples provided by Shell Oil also showed the presence of DMN but in lower
concentrations. If the ion exchange resin is the..source of N-nitroso
compounds, this could have significant public health implications in
some deionizers in private homes.
After each air sample was collected, the KOH was transferred to a
glass bottle. The impinger was rinsed with distilled water several times,
and the rinse water added to the sample. From the volume received
it can be estimated that the rinse water could have contributed up to
8 ng DMN to each sample collected after the survey team departed from
Wood River and began using the contaminated water. Thus, after November 16
DMN levels in each sample may have been increased by approximately 8 ng.
While only DMN was found in the first set of Phase II samples, the
second set indicated N-nitroso compounds with elution times equivalent
to DPN, DBN and nitrosomorpholine. These had not been reported earlier.
In the two instances where day and night samples were collected,
the latter concentrations were higher in both cases, possibly due to the
reduced effect of photolysis after sundown.
The General Motors plant at McCook, Illinois, was of interest
because of the reported use of cutting oils at this facility. Some cutting
oils have been shown to contain N.-nitroso compounds. While downwind
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levels were insignificant, the upwind sample showed DPN, DBN and
nitrosomorpholine. These same compounds and DMN were also found downwind
of Black Leaf Products at Elgin, Illinois.
Wastewater samples collected during the second part of Phase II,
and unaffected by the contaminated distilled water, generally showed low
concentrations of nitrosamines. The presence of a compound having an
elution time equivalent to nitrosopyrrolidine (NPyr) in the effluent
sample collected at National By Products, Des Moines, has not been
reported earlier in aqueous samples. However, NPyr has been identified
in cooked or processed meat products (4).
During Part 1, six samples on Tenax columns were collected concurrently
with impinger samples as indicated in Table 3. Of these, five were
available for% comparison with NEIC data. Only the sample collected at
Indiana Gas and Chemical Corporation showed.a detectable nitrosamine
level. This sample indicated 9.4 ng/m 3 DMN. During Part 2, an additional
six samples were collected [ Table 5]. Three of these are available for
comparison. The sample at Eli Lilly Corporation was analyzed for
DPN, while the samples at Union Oil and Mobil 0i1 were analyzed for DMN.
Nitrosamines were not detected in any of these samples. Even while using
a more sensitive technique, in only one case did Research Triangle Institute (Rh)
find nitrosamines while NEIC measured these in all comparable samples.
Differences between NEIC and Rh results .may have occurred for several
reasons. The possible introduction of contaminants into NEIC samples,
discussed earlier, would have increased these results without affecting
Rh samples. On the other hand, the filter preceding the Tenax cartridge
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but not in the EPA sampling train could remove particulates and condensed
nitrosamines, particularly at low sampling temperatures, thereby lowering
Rh collection efficiency. In addition, the effect of low temperatures
on the collection efficiency of Tenax columns is unknown. Additional
data collection is underway in an attempt to determine the cause of
these differences.
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SUMMARY AND CONCLUSIONS
Samples in the vicinity of a number of different industries,
primarily sources of amines, have been collected and analyzed for
nitrosamines. This has been done under both summer and winter conditions
(Phase I and Phase II). Unfortunately, contamination problems that
arose during Phase II limit the ability to make definitive statements
regarding much of these data. The possibility of contamination of
distilled water requires further examination.
The data show that nitrosamines may be more prevalent during winter
months, possibly due to reduced decomposition rates at colder temperatures
and/or reduced ultraviolet radiation as the sun angle lowers.
While not substantiated by air sampling results, water samples
indicate that there are primary sources of direct emissions to the
environment of a number of N-nitroso compounds, several not reported
earlier. The compounds probably arise during the synthesis of other
compounds and are then emitted to the environment during the use or
modification of these products. Thus, N-nitroso compounds were observed
in chemical, pesticide and coke plant effluents and the surrounding air
as well.
The Phase I sampling did not present any evidence to substantiate
secondary production in the vicinity of amine sources. Only two air
samples showed nitrosamines and these were in the imediate vicinity of
the DuPont amine production unit. Effluent samples from DuPont, as
well as the Union Carbide Corporation showed that DMN was present however,
indicating that under the conditions that existed the decomposition rate
may exceed the rate of formation if secondary production was occurring.
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In addition to DMN compounds showing retention times equal to DPN,
DBN and nitrosomorpholine were detected in Phase II samples. These have
not been reported earlier in ambient air. Although nitrosamines were found
at a number of sites, there are no data that would indicate formation in
the atmosphere as opposed to the nitrosamine presence as a contaminant.
Separation of the two possibilities would require in-plant process and
waste stream sampling during periods when ambient nitrosamine levels
existed.
Limited data collected along major highways showed possible contri-
butions from diesel engine exhaust. These levels, however, were close to
the instrument detection limits. Diffusion from these highways and truck
traffic would introduce nitrosamines into rural areas, but these levels
are low compared to values observed near urban industrialized areas.
While nitrosamiries have been observed in a number of areas of the
Midwest, the values in air have been below 1 pg/rn 3 even when corrected for
collection and extraction efficiency. Additional data are still needed to
determine the cause of discrepancies between NEIC and Rh results. These
data are now being collected. In the absence of data indicating the level
at which health effects are observed and what these effects are, one
cannot safely speculate as to the significance of these numbers or the
population at risk. Where these compounds are discharged into waterways,
it is possible that they may find their way into drinking water supplies.
This has been routinely demonstrated with other compounds. However,
where health effects data are lacking, the safest posture is to assume
no threshold level exists and minimize the environmental impact of
known carcinogens wherever possible.
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REFERENCES
1. Walker, P., et al. Environmental Assessment of Atmospheric
Nitrosamines, Mitre Corporation, MTR-7152, February 1976.
EPA Contract 68-02-1495.
2. Summary Report on Nitrosamines, Health Effects Research
Laboratory, USEPA, January 1976.
3. Scientific and Technical Assessment Report on Nitrosamines,
Office of Research and Development, USEPA, Rept. No.
EPA—600/6-77-OO1 , November 1976.
4. Assessment of Scientific Information on Nitrosamines, A Report
of an ad hoc Study Group of the USEPA. Science Advisory Board
ExecutiV&Töhimittee, August 1976.
5. Atmospheric Nitrosamine Assessment Report, Office of Air Quality
Planning and Standards. Research Triangle Park, N.C. March 1976
(draft).
6. Fine, D. i-I. N-Nitrosamines in Urban Community Air, Progress
Report, EPA Contract 68-02-231214, January 1976.
7. Pellizzari, E. D. Identification and Estimation of N-Nitrosocli—
methylamine and Other Pollutants in the Baltimore, Maryland
and Kanawha Valley Areas. Progress Report. Prepared by Research
Triangle Institute. EPA Contract 68-02-1228. January 1976.
8. Dimethylnitrosamine (DMN) Sampling Program, Belle, W. Va.,
December 1-5, 1975, E. I. DuPont DeNemours &,Co., Inc.
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APPENDtX A
ANALYTICAL PROCEDURES AND QUALITY ASSURANCE
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NEIC ANALYTICAL PROCEDURE FOR NITROSAMINES
Air Samples
Air samples were collected in foil-covered impingers (SGA
catalog #JV8550) filled with 60m1 of iN KOH. Air samples were drawn
through the impinger by a vacuum pump and the flows metered by a calibrated
stainless steel hypodermic needle (B&D #21). Normal collection volumes
range from 180 to 200 liters of air.
All laboratory work was carried out under low UV “bug” lights
to minimize the possibility of light catalyzed degradation of the nitrosamines.
The KOI-I solutions were extracted in a 125 ml separatory funnel with three
8 ml portions of dichiorornethane (Burdick and Jackson, “distilled in glass”).
The combined extracts were concentrated to 0.5 ml in Kuderna-Danish
evaporative co’ncentrators,each consisting of a three ball Snyder column
attached to a specially made 50 ml concentrator flask which in turn was
attached to a 4-ml calibrated receiving tube. The column and receiving
tube are available through Kontes Glass Company; the 50-ml flask was custom
made locally. Before concentration, 0.5 ml of 2,2,4 trirnethyiPentafle was
added as a keeper. A hot water bath maintained at 58 to 60°C was used as
the heat source.
Microliter aliquots of the concentrates were injected into a Varian Model
600D gas chromatograph attached to a Thermo Electron Corporation Thermal
Energy Analyzer (GC/TEA). An isopropanol/liquid nitrogen cold trap was
used in conjunction with the TEA.
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Where possible, samples thought to contain nitrosamines were spiked
with known standards to confirm retention time and to help establish concen-
trations. Two columns were employed in this work (i.e., 10% Carbowax 20M, 1%
KOH on 60/80 mesh Chromosorb WAW, 20 foot x 1/8 inch OD. stainless steel and a
similar column with 15% FFAP), and in all cases reported, the retention time
of the sample peaks matched those of the standard on both columns.
Unfortunately, the two columns employed elute nitrosamines in the same
sequence; different elution orders would have provided stronger support for
the reported results. A column with radically different properties,
however, was not available.
Quantitation of compounds reported was made by peak height comparison
with authentic standards. The DMN standard was obtained through Research
Triangle Institute, North Carolina, while the other standards were obtained
through the Food and Drug Administration, Washington, D. C.
Water Samples
Grab samples were collected in amber glass quart bottles with
teflon liners. Two 50-mi portions of dichloromethane were used to extract
each sample in a 2000—ml separatory funnel. The combined extracts were
concentrated as above, only using a 250-ml concentrator flask and 1 ml of
2,2,4 trimethylpentane as a keeper. In some cases it was not necessary to
concentrate to 1 ml in order to obtain measurable amounts of nitrosamines.
Normally, volumes injected into the GC/TEA were kept as small as possible.
Granular anhydrous sodium sulfate (Mallinkrodt AR) was used to treat
emulsions when they occurred during extractions.
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The detection limit for DMN was established at 4 ng/sample or assuming
0.2 m 3 air samples, this would correspond to 20 ng/m 3 for air samples and
20 ng/l for water samples. The detection limit for the other nitrosamines
reported increase in almost direct proportion to their molecular weight.
QUALITY CONTROL
During these studies, the following quality control considerations
were evaluated:
Solvent Blanks
Methylene chloride (dichioromethane - DCM) was concentrated from at
least three different bottles from 100 nil to 1 ml using an isooctane keeper
and was found to contain no peaks which specifically interfere with the
analyses. Similarly, unconcentrated Burdick and Jackson methylene chloride
and isooctane were analyzed with the TEA/CC system and found to be free
from interferences.
Field Blanks
During the sampling period extending from the end of November through
the beginning of December, two bottles of washwater were used. Twenty to
30 ml of this washwater per sample is used to rinse impinger solutions into
sample containers.
When these one-gallon bottles were returned to Denver they were
analyzed individually: one showed no contamination, while the other contained
about 250 ng/l of what again appeared to be DMN. It is believed that this
contaminated wash water was obtained from the Shell Oil Company, Wood River
Refinery in which case contamination of samples from this source would have
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occurred only after November 16 and at a level of approximately 5-8 ng/sample.
Several of the septum capped standard solutions were found to lose
solvent even when stored in a refrigerator. In order to check for possible
contamination of the refrigerator by nitrosamines in these standards,
an open beaker of 100 ml DCM was exposed overnight. The solution was found
to absorb what appeared to be DMN, but no other nitrosamines. Subsequent
washing of the interior of the refrigerator has substantially reduced the
concentration of this material to barely measurable levels, however, sample
storage in this refrigerator has been discontinued. These results open
the possibility that all sample extracts originally stored in the refrigerator
may have become contaminated with DMN even though they were kept in capped
bottles which had teflon liners and were wrapped with teflon tape. This
possibility includes all samples in this report collected between November 11-17,
1976.
Extraction Efficiencies
Quart samples of water were spiked with DMN, DEN (diethyl-N-nitrosarnine)
and DBN (dibutyl-N—nitrosamine), extracted and concentrated in the normal
manner to determine recovery from water samples. The average recoveries were as
follows: DMN 32% DEN 87% and DBN96%.. The effect of addition of NaC1 to
increase recovery during water extractions is presently being studied.
Overall co1lectjon and extraction efficiency was determined for air
samples by passing known quantities of dimethyl-N-nitrosamine, ethylmethyl—
N-nitrosamine, diethyl—N-nitrosamine, dipropyl-N-nitrosamine, ethylbutyl-N-
nitrosamine, nitrosopyrrolidine, and nitrosomorpholine through KOH impingers
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at ambient temperatures of -2°C and 20°C, then extracting and concentrating
as usual. For these compounds the average recovery at -2°C was 65% and at 20°C
78%. There was no apparent difference in efficiencies between the various
compounds examined.
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