EPA-560/5-77-001
PRIORITIZED GUIDELINES FOR
ENVIRONMENTAL FATE TESTING
OF ONE HALOGENATED HYDROCARBON
CHLOROBENZENE
January 1977
FINAL REPORT
Office of Toxic Substances
U.S. Environmental Protection Agency
Washington, D.C. 20460
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EPA-560/5-77-001 TR 76-591
Prioritized Guidelines for
Environmental Fate Testing
of One Halogenated Hydrocarbon:
Chlorobenzene
Author
Philip H. Howard
January 1977
Final Report
Contract No. 68-01-2679 Task 3
\
Project Officer:
Patricia Hilgard
Prepared for:
Office of Toxic Substances
U.S. Environmental Protection Agency
Washington, B.C. 20460
Document is available to the public through the National Technical Information
Service, Springfield, Virginia 22151
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NOTICE
This report has been reviewed by the Office of Toxic Substances, EPA, and
approved for publication. Approval does not signify that the contents necessarily
reflect the views and policies of the Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or recom-
mendation for use.
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Table of Contents Page
I. Introduction 1
II. Development of Environmental Fate Testing Protocols for 3
Toxic Substances
A. Existing Environmental Fate Testing Documents 3
B. Chlorobenzene Case Study . 6
III. Conclusions and Recommendations 20
REFERENCES 21
ii
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List of Tables Page
1 Chemical Marketing Data for Chlorobenzene 8
2 Physical Properties of Chlorobenzene 10
3 Calculations of Bioaccumulation and Evaporation Rates From
Physical Properties 12
iii
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I. INTRODUCTION
In order to assess the potential environmental hazards associated with the
commercial use of chemical substances, tests on their environmental fate and
biological effects need to be conducted. The number, extensiveness, and cost
of these tests should be dependent upon such factors as the quantity of the
chemical being used and the likelihood of the chemical being released to the
environment. In order to provide a relationship between environmental exposure
and the degree of testing, priorities and protocols for the tests are required.
This report is a first step in developing such priorities and protocols for
determining the fate of chemicals which are the responsibility of EPA's Office
of Toxic Substances. In this report, environmental fate is defined as all trans-
port (including bioconcentration) and alteration (including degradation) pro-
cesses which take place in nature; excluded are any biological effects. The
fate of an environmental contaminant has considerable impact upon its potential
adverse effects since the environmental fate processes determine the form and
quantity of the contaminant that may reach a sensitive biological site.
One case study chemical was selected from the chlorinated hydrocarbon
family, a group of chemicals that has provided numerous environmental pollution
problems (e.g. DDT, dieldrin and related compounds, PCB's, hexachlorobenzene).
Using this sample, the types of environmental testing will be discussed and
priorities for testing will be suggested. The case study compound, chloro-
benzene, provides an example of a high production volume, water insoluble,
fairly volatile chemical that is probably released to the environment in sig-
nificant quantities. However, there are many commercial organic compounds
(e.g., gases and solids, and compounds capable of dissociation), as well as
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other chemical compounds, for which the test case will provide little insight
into the type of environmental fate testing that should be undertaken. These
compounds need to be considered in future reports.
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II. DEVELOPMENT OF ENVIRONMENTAL FATE TESTING PROTOCOLS FOR TOXIC SUBSTANCES
A. Existing Environmental Fate Testing Documents
The Office of Toxic Substances, EPA, has funded two companion studies
which have reviewed and evaluated test methods for determining environmental
persistence and routes of degradation (Howard e_t al., 1975) and environmental
transport (Witherspoon et^ a^., 1976). These reports provide a good reference
to the test methods that are available, their reliability and reproducibility,
and relative cost, but little attempt was made to design protocols or prioritize
the tests for individual chemicals.
In 1974, Woodard conducted a survey of test methods that were used by
industry to indicate health hazards from individual chemicals. He organized
the methods into categories of studies that were conducted in response to four
levels of exposure. The levels of exposure with the environmental fate tests
that are conducted follows:
Level I Exposure - chemical is still in laboratory, or pilot plant
production where a limited number of persons may be exposed.
Fate Tests: None
Level II Exposure - more persons involved in the production or
industrial use of the chemical, but exposure rates are low.
Fate Tests: Half-life determinations in water and
soil, etc.
Biological or chemical oxygen demand
(BOD, COD)
Level III Exposure - more individuals become exposed through occu-
pational, hobby, repair, or incidential chemical contact.
Fate Tests: Biodegradation
Metabolic or decomposition products
Transport mechanisms
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Level IV Exposure - use so widespread that nearly everyone is
exposed to the chemical or use is such that exposure to it
in small amounts becomes unavoidable (this level frequently
is only reached after adverse findings or publicity).
Fate Tests: Disposition
Sewage treatment
Incineration
Landfill
Food-chain accumulation
Although the survey by Woodard (1974) focused on toxicity test methods, it did
provide some insight into the ordering of environmental fate tests that are pre-
sently being conducted by some chemical companies.
One category of chemicals that routinely receives environmental fate
testing is pesticides. EPA's Pesticides Office has published proposed guidelines
for registering pesticides, as well as an Appendix VI (EPA, 1975), which pro-
vides considerable detail as to the recommended tests and methodology to be
used. A list of the tests to be run follows:
ENVIRONMENTAL CHEMISTRY - Appendix VI (EPA, 1975)
Chemodynamic parameters
Water solubility
Partition coefficient
Dissociation constant
Adsorption
Hydrolysis studies
Photochemical studies
Leaching studies
Laboratory
Field
Volatilization studies
Laboratory soil metabolism studies
Field dissipation studies
The protocols in Appendix VI provide clear guidelines for the environ-
mental fate testing that needs to be conducted to register a pesticide, but the
order in which the protocols should be conducted is only implied. For example,
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the water solubility needs to be determined before the hydrolysis study so
that the concentration used in the hydrolysis study does not excee^ the water
solubility. No correlation between the quantity of pesticide .o be used and
the amount of testing to be conducted is stated. In fact, because the guidelines
in Appendix VI are only proposed, the tests that have to be run to register a
new pesticide may vary considerably. The Pesticide Office presently uses an
informal procedure of advice and comment for guiding pesticide companies who
are attempting to generate environmental fate data for registration (Ney, 1977).
With chemicals reviewed by the Office of Toxic Substances, some correlation be-
tween the quantity of a chemical being used and.the amount of testing is needed.
Also, the pesticide protocols emphasize the soil medium9 which is quite reason-
able for pesticides sprayed on crops, but such emphasis may not be justified
for many of the chemicals that the Office of Toxic Substances will consider.
Thus, although the guidelines for registering pesticides provide a starting
point for environmental fate testing protocols for the Office of Toxic Substances
(OTS), they need to be modified and prioritized considerably for OTS use.
The available documents on environmental fate testing indicate that
design of the experimental procedures frequently is on an ad hoc basis and
extremely variable. The contrast between toxicity testing and environmental
fate testing is particularly apparent from the report by Woodard (1974), where
such tests as acute oral LD,. are well understood and estimates of the cost of
the tests are available (Gehring et^ al_. , 1973). In contrast, with environmental
fate testing, little standardization is available (although Appendix VI provides
good guidelines), and the costs are virtually unknown (see Howard e_t^ al. 9 1975
and Witherspoon at al_., 1976 for some approximations). This lack of standardi-
zation is perhaps justified by the almost infinite ways that chemicals may be
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released to and reside in the environment. However, the hazard involved in
unstandardized tests is that considerable amounts of money and effort may be
spent in an attempt to determine the environmental fate of a chemical, but
result in little insight into the transport and degradation processes if the
test is not well designed (for an example of this, see Howard and Saxena, 1976).
Also, the interpretation of unstandardized tests frequently varies, which makes
it difficult to compare one chemical to another.
B. Chlorobenzene Case Study
Protocols for environmental fate testing of a chemical should reflect
an evaluation of all the available information including chemical marketing and
physical-chemical data. Chemical marketing data provides insight into the
quantities of the chemical that might be released and the medium into which
the release will initially occur. This provides guidance for the extent of
testing that is justified and the type of tests that should be undertaken. For
example, a compound used as a chemical intermediate whose production volume is
less than 100,000 pounds probably should only receive inexpensive screening
tests, or perhaps no fate testing at all. Depending upon the results from screening
tests (e.g., a compound may appear to be very persistent), more testing may be
necessary. Compounds used as solvents (probably lost to the atmosphere) should
be tested first in the vapor phase, while chemicals that are deposited in land-
fills should be tested first with soil systems.
Physical and chemical data can be used to estimate stability in the
environment and routes of transport (bioaccumulation, evaporation, leaching, etc.).
Such estimates will be considered with the test case chemical.
In considering the case study, information on toxicity, environmental
monitoring, and environmental fate, although available, has been ignored in order
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that the test case be more representative of an existing or new chemical for
which the Office of Toxic Substances (OTS) will be called upon to design protocols.
Most of the chemical marketing data and chemical and physical properties will be
available for all the chemicals reviewed by OTS. Information on toxicity should
have an impact upon the degree, but not the type, of environmental fate testing
to be conducted. Extremely toxic or carcinogenic, mutagenic, or teratogenic
chemicals should be extensively tested for environmental fate. However, rarely
will a complete toxicologic evaluation be available and, therefore, the extent
and type of environmental fate tests should rely heavily on estimates of the
amount released to the environment and physical and chemical properties. Also,
toxicologic evaluations would not consider hazardous degradation products which
might be formed in the environment.
Ambient monitoring data may be used to establish protocols for existing
commercial chemicals, but will be of little use with new products. Monitoring
should not be used as a substitute for good environmental fate testing, or visa
versa, because frequently chemicals have not been detected until after levels
causing adverse effects have been reached and considerable time may be required
to eliminate the contamination. Also, intermedia transport (e.g. evaporation
from soil) may provide misleading monitoring data concerning the environmental
fate of a chemical. Thus, environmental monitoring should be used as a check
on environmental fate testing of known chemicals and as a way to identify un-
recognized contaminants which may have slipped through the pretesting procedures
(e.g. by-products from commercial processes).
The following sections outline a procedure for devising environmental
fate testing protocols for chlorobenzene. No attempt has been made to determine
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the exact extent of testing that is required, since such details need to be
considered relative to other chemicals and in terms of cost-benefit. However,
ordering of the tests has been attempted and interrelationships between the
tests have been examined.
Step 1 - Review Available Information
Step 1 a - Consideration of Chemical Marketing - Environmental
Release Data
Table 1 summarizes the chemical marketing information on
chlorobenzene. The chemical is mostly used as a chemical intermediate, which
should reduce the amount of the chemical that is released to the environment.
Table 1. Chemical Marketing Data for Chlorobenzene (SRI, 1975)
Chlorobenzene (Millions of Pounds)
Capacity
Production
Imports
Exports
Consumption
Phenol Production
Chloronitrobenzenes Production
DDT Production
All Other3
655
403.5
-
-
110
130
20
144
(1974)
(1972)
(1972)
(1972)
(1972)
(1972)
Total
404 (1972)
Trade literature estimates that at least 50 million pounds per year
of chlorobenzene are used as solvents.
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However, significant quantities (50 million pounds annually) appear to be used
for solvent purposes, which might result in significant release to water systems
(if the solvent is used in contact with water) or the atmosphere (during use or
distillation recovery). Presumably, more detailed marketing and perhaps environ-
mental release information would be available to the Office of Toxic Substances.
However, the available information suggests that environmental fate testing in
simulated atmospheric systems and in water should be considered. If some of the
solvent applications result in disposal in landfills, soil systems may also be
considered.
Tests such as Warburg or model activated sludge systems indicate
the treatability of a chemical in an activated sludge water treatment plant.
Such tests provide indications of environmental release when a chemical is
treated in a biological water treatment plant, but provide only limited in-
formation on biodegradability in natural water systems. Thus, such tests should
not be considered environmental fate tests.
Step 1 b - Evaluations of Physical and Chemical Properties
Chlorobenzene is a liquid at ambient temperature with a
relatively high vapor pressure (9 mm Hg at 20°C), intermediate partition co-
efficient, and low water solubility (360 ppm). The ultraviolet absorption
spectrum in isooctane indicates only very slight absorption above 280 nm
(A = 271 nm). However, correlations between absorption spectra and photo-
degradation are poorly understood. Direct absorption of energy is not re-
quired for photolysis (e.g. sensitizer reactions). Other physical properties
of chlorobenzene are listed in Table 2, but they have little importance to
environmental fate. The chemical structure of .chlorobenzene (chlorinated
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Table 2. Physical Properties of Chlorobenzene
(Hardie, 1964)
°C
°C
(octanol/water)
melting point,
boiling point,
steam distillation point,
log partition coefficient'
water solubility'5
U 0°C
10°C
16.5°C
•S
15°C
20°C
surface tension, dyn/cm
15°C
20°C
specific heat, C (T = °K)
critical temperature, °C
critical pressure, mm Hg
critical density
explosive limits in air, vol %
lower, 100°C
upper, 150°C
flash point, °C
dielectric constant
20°C
70°C
. 106°C
at bp
dipole moment (dil. benzene soln.), esu
heat of combustion (at constant pressure), kcal/g-mole
latent heat of vaporization, keal/g-mole
viscosity, cP
15°C
30°C
60°C
120°C
130°C
vapor pressure, mm Hg
0°C
20°C
40°C
60°C
80°C
100°C
120°C
-45.21
131.5
90
2.88
360 ppm
1.1293
1.1167
1.1058
1.52748
1.52460
33.86
33.28
0.2988 + 0.00074 T
359.2
33962
0.3654
1.8
9.6
24
5.6493
4.886
4.435
4.144
1.58 x 10
763.88
8.73
0.844
0.711
0.512
0.313
0.292
3
9
26
65
144
292
543
18
Leo et_ al., 1971
Metcalf and Lu, 1973
10
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aromatic) suggests that it would be fairly stable in the environment by analogy
with other well known contaminants (DDT, PCB's, hexachlorobenzene). Such
structure-environmental fate correlations should be used whenever possible
(see review in Howard et_ al., 1975).
The physical properties can be used to estimate the rates of
transport of a chemical that is released to the environment. These calculations
for chlorobenzene are summarized in Table 3, where calculated values for benzene
and DDT are provided for comparison. The calculations indicate that chloro-
benzene has a low potential for bioaccumulation and should evaporate relatively
fast from water (C _/C = <100 is defined as a chemical that is rapidly lost from
ttrtW ' C&1.L
water surfaces). The calculated values should be used with caution since they
are only estimates that may give misleading impressions. For example, although
the calculated ecological magnification for chlorobenzene is 9, the experimental
value is 645 (Metcalf and Lu, 1973), which is comparable to the experimental
value for tetrachlorodibenzodioxin (calc. = 25,000; exper. = 822) and hexachloro-
benzene (calc. = 20,000; exper. = 343).
Nevertheless, the physical properties can provide considerable
insight into the type of testing that should be considered. With chlorobenzene
in water, it appears that a major loss mechanism may be volatilization. Whether
degradation processes in water can compete will have to be determined experi-
mentally. The calculations also emphasize the importance that atmospheric processes
are likely to play in the environmental fate of chlorobenzene.
Step 1 c - Review Literature on Chemical Reactivities and
Product Formation
Literature searches are considerably cheaper than experi-
mental work, and, therefore, the former should be undertaken before any
11
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Table 3. Calculations of Bioaccumulation and Evaporation Rates from Physical Properties
Bioconcentration Factor
Calculated From
Partition Coefficient
Ecological Magnification
Calculated From,
Water Solubility
Half-life (Hours)
of Evaporation From
Water Calculated From
Vapor Pressure, Water
Solubility, and Molecular
Weight0
Ratio CH20/Cair
Calculated From
Vapor Pressure
and Water Solubility'
Chlorobenzene
46
5.8
6.12
DDT (for comparison)
Benzene (for
comparison)
650
19
29,300
4
73.9 326
4.81 4.5
? Neely £t al. (1974)
Metcalf and Lu (1973)
, Mackay and Leinonen (1975)
Appendix VI Guidelines for Registering Pesticides
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experimental work begins. Information may already be available that would
eliminate the necessity for some or all (highly unlikely) of the environmental
fate tests. Also, examination of previous studies will provide insight into
analytical methods that might be used and breakdown products that might be
formed.
A preliminary examination of available information on
chlorobenzene indicates that its degradation in aerated lagoons (Garrison, 1969)
and activated sludge has been examined and its photolysis (wavelength less than
253 nm - not representative of sunlight) in the gas phase studied (Ichimura et
al. , 1973). Also, Gibson et^ al. (1968) found that chlorobenzene is converted
to 3-chlorocatechol when it was incubated with Pseudomonas putida grown with
toluene as a sole source of carbon; this information will assist in the identi-
fication of degradation products. In addition, as previously mentioned, the
ecological magnification in a model ecosystem has been determined (Metcalf and
Lu, 1973).
Step 2 - Development of Any Missing Physical Parameters
After reviewing the available information, there may be some
missing physical parameters (e.g., water solubility, partition coefficient,
vapor pressure, dissociation constant). The partition coefficient may be ob-
tained from the tabulation of Leo et^ aJL. (1971), calculated using additivity
principals (Hansch et al., 1972), or measured experimentally (see Pesticide
Registration Guidelines Appendix VI for methodology). The other physical
properties will have to be measured experimentally (see Appendix VI). With
chlorobenzene, a dissociation constant is unnecessary since chlorobenzene does
not dissociate. The water solubility, vapor pressure, and partition coefficient
are available.
13
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These physical properties should be measured before experiments
on degradation and transport are begun so they can be used in designing the
experimental test conditions.
Step 3 - Screening Tests
Tests can be divided into three categories by analytical method:
(1) tests that require no analytical method for the chemical (e.g. BOD, Warburg -
both measure consumed oxygen) (this lack of analytical method only applies to
degradation tests, not transport studies) (2) tests that require specific analy-
tical methods for the chemical, and (3) tests that use radiolabelled material.
The use of radiolabelled chemicals for environmental fate testing is the most
desirable because it allows for a mass balance of the test chemical and products,
is very sensitive, and combined with thin layer chromatography can provide in-
sight into the breakdown products. Chemical analytical methods allow the in-
vestigator to follow the disappearance of the parent compound and, if he knows
what products to expect, to develop analytical methods for the degradation
products. In some instances, radiolabelled parent compound may not be avail-
able or an analytical method needs to be developed for the degradation products,
and the cost of synthesis or analytical method development are not justified.
In these instances, a variety of screening tests may be considered. Examples
of such tests are:
BOD
Warburg
River die-away
2-day Hydrolysis and photolysis studies under acidic, neutral,
and basic conditions (see Wolfe et al., 1976)
Soil adsorption or TLC studies
Rapid evaporation studies from water
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Rapid screening tests such as these usually measure the relative increase in
oxygen uptake or the disappearance or transport of the test chemical. Long-
path infrared cells, which have been used to study atmospheric photooxidation,
might also be considered in this category since an analytical method does not
need to be developed (infrared absorption). However, the equipment is so ex-
pensive and complicated that it should not be considered a screening test.
Screening tests have the advantage that they are rapid and
inexpensive. However, they provide very limited information on the environmental
fate of a chemical. With BOD and Warburg, the parameter being measured, oxygen
uptake, is only an indirect indication of degradation. The results are diffi-
cult to interpret unless extremes, such as no oxygen uptake or 100% of the theore-
tical oxygen demand are found, which is rarely the case, and the conditions of the
Warburg test are more similar to an activated sewage treatment plant than to
natural conditions. The die-away and hydrolysis tests only determine the rate
of disappearance of the test compound (good indication of persistence), but pro-
vide little insight into the degradation products, which is equally important.
With chlorobenzene, if screening tests are the only ones justi-
fiable, a BOD and river die-away test probably should be run, and perhaps a
rapid photolysis study in hexane (provide preliminary indications of the atmo-
spheric photooxidation). Since chlorobenzene is very stable in water, hydrolysis
studies do not seem justified. The Warburg test indicates treatability rather
than environmental fate and, therefore, should not be undertaken unless it is
anticipated that sizable quantities of chlorobenzene will pass through an acti-
vated sludge treatment plant. Because of the limited information provided from
the screening tests, it seems reasonable to consider avoiding these tests if
14
more detailed studies are anticipated. Also, 100 yCi of C uniformly labelled
15
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chlorobenzene is available for about $80, so it would seem more reasonable to
conduct any screening tests with radiolabelled material (BOD and Warburg are
exceptions).
Step 4 - Intermediate Tests
Tests in this category, with the exception of atmospheric photo-
oxidation systems, are generally characterized by the use of radiolabelled material.
The difference between this category and the following category of more detailed
studies is that any major (> 10% - Appendix VI Pesticide Guidelines) degradation
products may be characterized (e.g., TLC mobility, gas chromatography retention
time, UV absorbance on TLC (+ or -), radioactive content, or possible TLC spray
reactions - Pesticide Guidelines Appendix VI), but not chemically identified.
Rigorous and complete chemical identification is extremely time consuming and
expensive, although the use of GC-MS systems has considerably simplified the
process. Environmental fate tests that fall into an intermediate category in-
clude the following:
Atmospheric
Long-path infrared cells
Plastic containers
Glass flask reactors
Water
Hydrolysis studies (various pH and temperature - determine the
kinetics)
Photolysis with simulated sunlight in various matrices (determine
kinetics - use sensitizers and natural water)
Die-away tests with radiolabelled material (sea, lake, river
water from various sources to provide a wide spectrum of
microbes, pH, pollution, organic content, etc. - include
with and without sediment, sterile control, aerobic and
anaerobic conditions)
Shake culture tests
Shake culture using pure cultures
Model sewage treatment systems
16
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Soil
Soils incubated with test chemical (aerobic, flooded, anaerobic
conditions, soils suspended in water)
Pure cultures isolated from soil
Greenhouse studies
Transport
Volatility - from water (Billing et^ al., 1975)
Bioaccumulation and biomagnification - terrestrial-aquatic or
aquatic model ecosystems (Metcalf method, Isensee method)
Uptake by individual biota
Desorption from organisms
The above list illustrates the considerable number of laboratory tests that may
be undertaken to determine the environmental fate of a chemical. Not included
are the many variations of the above tests that are possible (see Howard et al.,
1975; Witherspoon je£ al., 1976). Some techniques, such as the use of pure culture,
might more appropriately be used to determine the pathways of degradation (next
category). Results using pure culture, although they have been used to indicate
persistence (ability to use a chemical as a carbon and energy source), are diffi-
cult to relate to the rates of degradation that might take place in nature.
Without considering a particular compound, it is extremely diffi-
cult to prioritize the above tests. With chlorobenzene, it would appear to be
important to determine the rate and products of atmospheric photooxidation, the
rate of evaporation from water, and the rate and products of degradation (chemical
and biological) in water. If the rate of degradation in water is slow compared
to the rate of evaporation, studies of the atmospheric photooxidation will be
considerably increased in importance. Products of atmospheric photooxidation
(e.g. perhaps chlorophenols) are probably less volatile, suggesting that they
should be studied in water or soil systems, although considerable insight into
the behavior of chlorophenols in soil and water is already available. Long-path
infrared cells for atmospheric tests have the advantage that no analytical method
17
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needs to be developed. However, the equipment used for atmospheric studies is
not available in many laboratories, so plastic or glass containers may be pre-
ferred. The analytical method used, the scheduling of tests, etc. should be
left to individual researchers.
Step 5 - Detailed Laboratory and Field Tests
Studies in this category include techniques oriented at chemical
identification of intermediates, determination of pathways of degradation, tests
that examine in detail the effect of various conditions on reaction rates (e.g. the
effect of NO concentration on photooxidation rates - usually conducted in smog
X
chambers), and field tests. In general, studies in this category are very
expensive and time consuming. Detailed laboratory or field tests include:
Air
Smog chamber
Release and monitoring studies
Water
Die-away tests in treated ponds, lakes, streams
Treatability of a chemical in a commercial activated sludge
treatment plant
Pure culture techniques to determine pathways of degradation
Soil
Field plots - monitoring
Landfills - monitoring gases and leachate
Pure culture techniques to determine pathways of degradation
Transport
Field studies followed by monitoring biota, soil, water, etc.
Field studies suffer from low reproducibility because of the variable test con-
ditions, but provide the only results where natural conditions are used. However,
because radiolabelled material cannot be used, rarely are degradation products
examined, although they may be analyzed if the field test follows the inter-
mediate test, since the intermediate test may provide indications of the degra-
dation products that will be formed. It seems unlikely that techniques in this
18
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category should be used except for chemicals that are released to the environment
in very large quantities (e.g. pesticides - see Appendix VI, detergents, etc.).
If justified from release estimates, chlorobenzene should be tested in a smog
chamber and perhaps in a die-away test in a pond or lake. Stable metabolites, which
may have been determined from the intermediate tests, should also be monitored.
19
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III. CONCLUSIONS AND RECOMMENDATIONS
Establishing protocols for environmental fate testing of chemicals that
are of interest to the Office of Toxic Substances has been divided into five
steps:
Step 1 Review and evaluation of available information
Step 2 Development of any missing physical parameters
Step 3 Screening tests
Step 4 Intermediate tests
Step 5 Detailed laboratory or field tests
This is only a preliminary result which may need considerable revision
before implementation of test protocols. The tests recommended for one test
case chemical, chlorobenzene, are considered based upon commercial considera-
tions and chemical and physical properties. More experience is needed with a
greater variety of chemical compounds. The level of testing required should
be based upon the quantity of the chemical being released to the environment,
toxicity (if known), and a cost/benefit analysis.
20
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and Reactivities of Methylene Chloride, Chloroform, 1,1,1-Trichloroethane,
Trichloroethylene, Tetrachloroethylene, and Other Chlorinated Compounds in
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Environmental Protection Agency (1975), "Guidelines for Registering Pesticides
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Gehring, P.J., Rowe, V.K. and McCollister, S.B. (1973), "Toxicology: Cost/Time,"
Fd. Cosmet. Toxicol. 11:1097-1110.
Gibson, D.T., Koch, J.R., Schuld, C.L. and Kallio, R.E. (1968), "Oxidative
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for the Office of Toxic Substances, EPA, Washington, D.C.
Howard, P.H., Saxena, J., Durkin, P.R. and Ou, L.-T. (1975), "Review and Evalu-
ation of Available Techniques for Determining Persistence and Routes of
Degradation of Chemical Substances in the Environment," EPA-560/5-75-006,
U.S. Nat. Tech. Inform. Serv. PB 243 825/7WP.
Ichimura, T. and Mori, Y. (1973), "Photolysis of Monochlorobenzene in Gas Phase,"
J. Chem. Phys. _58_(1):288-92.
Leo, A., Hansch, C. and Elkins, D. (1971), "Partition Coefficients and Their
Uses," Chem. Rev. 21(6)=525-616.
Mackay, D. and Leinonen, P.J. (1975), "Rate of Evaporation of Low-Solubility
Contaminants from Water Bodies to Atmosphere," Environ. Sci. Technol.,
2(13):1178-1180.
Metcalf, R.L. and Lu, P.-Y. (1973), "Environmental Distribution and Metabolic
Fate of Key Industrial Pollutants and Pesticides in a Model Ecosystem,"
U.S. Nat. Tech. Inform. Serv. PB 225-479.
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Neely, W.B., Branson, D.R. and Blau, G.E. (1974), "Partition Coefficient to
Measure Bioconcentration Potential of Organic Chemicals in Fish," Environ.
Sci. Technol. £(13):1113-1115.
Ney, R., Personal communication, Pesticides Office, EPA.
Stanford Research Institute (1975), "Chlorobenzene - Salient Statistics,"
Chemical Economics Handbook, Menlo Park, California.
Witherspoon, J.P., Bondietti, E.A., Draggan, S., Taub, P.P., Pearson, N. and
Trabalka, J.R. (1976), "State-of-the-Art and Proposed Testing for Environ-
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TECHNICAL REPORT DATA
(Please read tauntctwns on the reverse before completing)
1. REPORT NO.
EPA-560/5-77-001
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
. Prioritized Guidelines for Environmental Fate
Testing of One Halogenated Hydrocarbon:
Chlorobenzene
5. REPORT DATE
January 1977
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Philip H. Howard
8. PERFORMING ORGANIZATION REPORT NO
TR 76-591
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Center for Chemical Hazard Assessment
Syracuse Research Corporation
Merrill Lane, University Heights
Syracuse, New York 13210
10, PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
EPA 68-01-2679
12. SPONSORING AGENCY NAME AND ADDRESS
Office of Toxic Substances
U.S. Environmental Protection Agency
Washington, D.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
Final Technical Report
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
Protocols for environmental fate testing of chemicals that are of interest
to the Office of Toxic Substances have been divided into five levels of increasing
complexity and cost: (1) review and evaluation of available information, (2)
development of any missing physical parameters, (3) screening tests, (4) inter-
mediate tests, and (5) detailed laboratory or field tests. Chlorobenzene is
used as an example to determine the types of tests to be run. The level of
testing required should be based upon the quantity of the chemical being re-
leased to the environment, toxicity (if known), and a cost/benefit analysis.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Environmental fate tests
Persistences
Biodegradation
Hydrolysis
Chlorobenzene
Photodegradation
b.IDENTIFIERS/OPEN ENDED TERMS
c. COS AT I Held/Group
18. DISTRIBUTION STATEMENT
Document is available to public through the
National Technical Information Service,
Springfield, Virginia 22151
19. SECURITY CLASS (Tills Report)
21. NO. OF PACib.S
22
20. SECURITY CLASS (Thispage)
22. PRICE
EPA Form 2220-1 (9-73)
23
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