22204
2-(2,4,5-trichlorophenoxy) Propionic Acid (Silvex)
Notice of Intent to Cancel Certain Registra-
tions of Pesticide Products Containing Silvex
I. INTRODUCTION
I am today issuing an emergency order suspending
immediately the forestry, rightsrof-way, pasture, commercial/
ornamental turf, home and garden, and aquatic weed control/
ditch bank uses of pesticide products containing silvex, and
a statement of reasons. Sect ion. 6(c)(1) of the Federal
Insecticide, Fungicide and Rodenticide Act (FIFRA) [7 U.S.C.
Section 136d(c)(D] provides that a suspension order cannot
be issued unless a notice of intent to cancel the registra-
tions or change the classifications of the pesticide products
concerned has already been issued or is issued with the
suspension order. For the reasons set forth below, I find
that forestry, rights-of-way, pasture, commercial/ornamental
turf, home and garden, and aquatic weed control/ditch bank
uses of pesticide products containing silvex, in accordance
with current use instructions, appear to pose an unreasonable
risk to humans. I am therefore announcing my intention, to
cancel all these registered uses of silvex under Section 6(b)
of FIFRA [7 U.S.C, Section 136(d)(b)].
LEGAL AUTHORITY
Section 6(b) of FIFRA [7 U.S.C. Section 136d(b)]
horizes the Administrator to issue a notice of intent
cancel the registration of a pesticide or to change
t classification if it appears to him that the pesticide
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or its labeling "does not comply with the provisions of
IFIFRA] or, when used in accordance with widespread and
commonly recognized practice, generally causes unreason-
able adverse effects on the environment." Thus, the
/
Administrator may cancel the registration of a pesticide
whenever he determines that it no longer satisfies the
statutory standard for registration which requires (among
other things) that the pesticide "perform its intended
function without unreasonable adverse effects on the
environment" [FIFRA Section 3(c)(5); 7 U . S .C . Section
136a(c)(5)3. He may also change the classification of any
use of a pesticide if he determines that such a change "is
necessary to prevent unreasonable adverse effects on the
environment" [FIFRA Section 3(c)(2); 7 U.S.C. Section
136a(d)(2)]. "Unreasonable adverse effects on the
environment" means "any unreasonable risk to man or the
environment, taking into account the economic, social and
environmental costs and benefits of the use of any pesticide"
IFIFRA Section 2(bb); 7 U.S.C. Section 136(bb)].
The burden of proof for establishing the safety of a
pesticide product to support a decision concerning
registration or continued registration rests at all times
on the proponent of registration [Environmental Defense
Fund v. Environmental _g.rjp_te.ct i on Agency, 465 F.2d 528, 532
(D.C. Cir. 1972); EOF v. EPA, 510 F.2d 1293, 1297 (D.C. Cir.
% -
1975); EOF v. EPA, 548 F.2d 998, 1004 (D.C. Cir. 1976)].
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In effect, FIFRA requires the Administrator to weigh
the risks and benefits associated with each use of a pesticide.
If he determines for any particular use that the risks
exceed the benefits, he must then determine whether those
risks can be sufficiently reduced (so that they are outweighed
by the benefits) by the imposition of restrictions upon use
through changes in the labeling and/or by the classification
of the use for restricted use. If he determines that
ade/jate risk reduction cannot be achieved by such regulatory
measures, the registration of the pesticide for that use
must be fully cancelled.
III. REASONS FOR INITIATING PROCEEDINGS TO CANCEL
A. Risks
On the basis of data available to the Agency, I
conclude that silvex and/or its contaminant, 2,3,7,8-
tetrachlorodibenzo-p-dioxin (TCDD), create a serious health
risk for humans and that human exposure to silvex and/or its
contaminant, TCDD, is cause for considerable concern.
The Agency has reviewed numerous studies in which
industrial, academic, and government scientists have reported
that TCDD and/or silvex contaminated with TCDD produce
fetotoxic, teratogenic, and carcinogenic effects in test.
animals that have been exposed to these chemicals. The
occurrence of these adverse effects in test animals following
exposure to silvex and/or TCDD indicates that humans who
are exposed to silvex may experience comparable effects.
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Concern for the health of humans who may be exposed to TCDD,
and therefore silvex contaminated with TCDD is heightened
because scientists have not demonstrated that there is a
level of exposure that has no adverse effects in humans.—
A recent EPA-sponsored epidemiological study shows
human miscarriages to be related both geographically and
temporally to the use of 2,4,5-T (a chlorophenoxy herbicide
closely related to silvex, and which also contains TCDD).
Specifically, the study indicates that women who live in an
Oregon area (Study area) where 2,4,5-T is used for forest
management experience miscarriages more frequently than do
women who live in other Oregon areas where there is little
or no known use of 2,4,5-T or other dioxin-containing
phenoxy herbicides. Most significantly, the data generated
through this study show that the increase in frequency of
miscarriages for women in the Study area is greatest two
months after the period when 2,4,5-T is used in this area,
and that there is a close correlation between the amount of
2,4,5-T used by month and the size of the increase in the
frequency of miscarriages two months later. Information has
recently become available to the Agency which documents the
use of silvex in the Alsea area during the period of time
T/ A Committee of the National Research Council of Canada
recently agreed with the authors of the World Health
Organization's monograph, on TCDD that "for TCDD a no-
effect level for man could not be established" (NRCC 1978).
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studied. However, even without this information, I would
have found that the serious implications of this study are
as applicable to silvex as to 2,4,5-T. TCDD, the contaminant
contained in both herbicides, is a potent mammalian fetotoxin
and teratogen at very low doses. Conversely, silvex and
2,4,5-T are fetotoxic and teratogenic at comparatively high
doses. It is reasonable to assume that the adverse human
reproductive effects observed in Alsea which have been
attributed to low-level exposure to 2,4,5-T are due primarily
to the TCDD in 2,4,5-T. Therefore, since silvex also
contains TCDD, I conclude that the Alsea data are applicable
to areas where silvex is used when evaluating potential
reproductive risk to humans.
I also conclude that it is prudent to assume that
individuals living in or frequenting areas where the
forestry use of silvex occurs may experience exposure to
TCDD qualitatively similar to that experienced by the Alsea
women and may suffer the adverse effects which silvex,
2,4,5-T, and/or TCDD produce. I further conclude that
individuals, living in or frequenting areas where the use
patterns of silvex create similar or greater possibilities
for exposure than the forestry use, have a potential risk of
adverse effects from silvex exposure. A comparable risk
potential is applicable to persons who are occupationally
exposed to silvex through these uses. Such use patterns
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include, without necessarily being limited to, the rlg'h't's-
of-way and pasture uses of silvex. Additional uses c,
silvex (home and garden, aquatic weed control/ditch tL-ik,
and commercial/ornamental turf uses) are comparable to uses
of 2,4,5-T cancelled or suspended in 1970 because of concern
that exposure to 2,4,5-T and/or TCDD posed an imminent
hazard to humans and to the environment. Because silvex
also contains TCDD, I conclude that it is prudent to take
similar action for these silvex uses. The Agency has
identified pesticide applicators and persons involved in
pesticide application support activities, and persons living
in or frequenting areas of silvex use as the principal
groups of individuals who may be exposed as a result of
the forestry, right-of-way, pasture, home and garden,
aquatic weed control/ditch bank, and commercial/ornamental turf
uses of silvex. Based upon animal data and other information
(including the recent Oregon study), individuals exposed to
silvex may suffer adverse reproductive effects or develop
cancer.
B. Determination of Benefits
The Agency has evaluated the economic effects of
cancelling non-crop uses of silvex. The non-crop uses of
silvex include those it has in common with major uses of
2,4,5-T (forestry, pasture, and rights-of-way), as well as
turf (home and garden and commercial/ornamental turf) and
aquatic weed control/ditch bank uses.
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Domestic usage of silvex is estimated to be about 2.8
to 3.3 million pounds annually. Commercial/ornamental turf
and home and garden uses of silvex are the largest volume
uses, comprising more than 50% of domestic usage. Aqtfatic
weed control/ ditch bank usage account for about 8% of
annual usage. Other uses, primarily pasture, account for
about 10% of use. The uses of silvex subject to this cancel-
lation notice account for about two-thirds of its annual
usage.
The Agency's analysis indicates that cancellation of
silvex non-crop uses would not significantly affect U.S.
production or prices of any commodities or services in
affected sectors. Economic impacts of the cancellation
would be minor in most cases, even at the local/regional
level. The major significance of cancelling silvex is that
it would not be available to replace 2,4,5-T on forest and
pasture sites.
The economic impacts of cancelling each of the non-
crop uses of silvex are discussed below.
(1) Forestry
The cancellation of forestry uses of silvex would
not have any significant economic impact because the chemical
is not now in use. The principal potential useis, the
Department of the Interior (USDI) and the U.S. Forest
Service (USFS), have already discontinued "se. The signifi-
cance of the silvex cancellation for fores-t^y use is that, it
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would not be available as a substitute for 2,4,5-T. However,
silvex is not an acceptable substitute for 2,4,5-T on aany
acres because it is toxic to pines. Thus, impacts would
be limited to non-pine Western conifer forests and some
Northeastern fir spruce stands.
Silvex has been used in,forestry mostly by the U.S.
Department of the Interior, on parts of approximately 2
million acres of Bureau of Land Management (BLM) lands;
lesser amounts have been used by the USFS. Silvex is used
prior to planting for site preparation and later to assist
growth of young trees by "releasing" them from competing
hardwood trees and brush.
There are many alternatives to. silvex for site
preparation. Several chemicals (2,4-D, pic loram, Atrazine,
Banvel, and dicamba), as well as mechanical, methods,
controlled burning, and combination methods, may be
effectively used for this purpose.
Release of young conifers requires a selective
herbicide or manual methods to reduce hardwood competition.
Silvex, 2,4,5-T, and 2,4-D are the only Federally registered
chemicals providing this selective control. Silvex and
2,4,5-T are preferred because 2,4-D controls a more limited
spectrum of woody species.
Silvex is not widely used in forest site preparation/
release activities. So far as is known, the only extensive
recent use of silvex has been by BLM in western Oregon.
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However, BLM has used no herbicides since 1977. The USFS
treated approximately 2,700 acres of forest lands wicU 1,750
Ibs of silvex in 1977. USDI is presently considering
prohibiting the use of silvex. Plans have been developed
for vegetation management without silvex.
(2) Rights-of-Way ,
The economic impact of cancellation of the use of
silvex on rights-of-way would be minimal. Chemical, manual,
and mechanical methods are used on highway, electric,,
railroad, and pipeline rights-of-way acres to control woody
and.herbaceous plants that would otherwise impede, the use
of equipment, interfere with inspection and maintenance and
in extreme situations interfere with the functioning of the
right-of-way system.
.'„ - Manual and mechanical methods are the most common
control practices on rights-of-way acreage. Present usage
of silvex for rights-of-way vegetation control is minimal,
e.g., less than 2% of rights-of-way firms use it. If
silvex were not available, users could treat with other
herbicides. Dichloroprop, 2,4-D, and.picloram mixed with
2,4-D are all cheaper than silvex, and in some instances are
more effective;
(3) Pasture
The phenoxy herbicides (2,4-D, 2,4,5-T and silvex)
are registered for the control of .many woody and herbaceous
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weeds on pasture.— Silvex is -generally more effective for
woody plant control than 2,4-D, but less effective that!
2,4,5-T. No more than 250,000 Ibs of silvex are used oa'
pasture acreage each year.
Other chemicals, such as pelleted formulations of
picloram, dicamba, 2,4-D are generally preferred to silvex
for pasture use. Therefore, farmers-who currently use
silvex would turn to these alternative herbicides. The use
of alternatives would prevent reductions in yield or pro-
duction. Therefore, there would be no impact on consumer
prices, or the general economy. Agricultural income may be
reduced by an immeasurably small amount.
(4) Commercial/Ornamental Turf •-''
Silvex is used on various types of commercial and
ornamental turf, such as golf courses, athletic fields,
parks, playgrounds, highway turf, and turf farms. Golf
courses are the principal use. Annual usage could be >'
as much as 2 million pounds of active ingredients.
Effective alternatives are available. Among them
are 2,4-D, MCP.P, and dicamba. Use of alternatives could
increase costs by about $3.50/acre. However, the use of
these more expensive alternatives would not add substantially
^Y Pasture is defined as land producing forage for animal
consumption, harvested by grazing, which has annual or more
frequent cultivation, seeding, fertilization, irrigation,
pesticide application an^d other similar practices applied
to it. Fencerows enclosing pastures are included as part
of the pasture.
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to overall turf maintenance costs in most situations. For
example, turf maintenance for golf courses now costs
approximately $80-90 per acre. Thus, the economic impact of
cancelling, silvex use would not be highly significant.
(5) Home and Garden
Several hundred thousand pounds of silvex are used
per year on home lawns and garden areas. Most of the
herbicides used by homeowners in the U.S. are for control of
broadleaf weeds and grass pests in lawns. However, most
homeowners do not use any herbicides.
Several equally efficaceous alternatives to silvex,
are available and comparable in cost. Homeowners could
shift to products containing 2,4-D, MCPP, and dicamba
without experiencing inconvenience. Thus, homeowner impacts
stemming from cancellation would be negligible.
(6) Aquatic Weed Control/Ditch Bank
Aquatic weeds are a nuisance in water bodies used for
recreatibn and in farm ponds used for watering livestock.
Major uses of herbicides for aquatic weed control*are
government and private recreational organizations and
farmers. Economic effects of cancelling aquatic/ditch
bank uses of silvex would be nominal because effective,
economical alternatives (2,4-D, diquat, endothall, dichlobenil,
and biological controls) are generally available.
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C. Conclusion
On the basis of information currently available,
I conclude that the risks posed by the continued use of
silvex on forests, rights-of-way, pastures, homes and
gardens, commercial/ornamental turf and aquatic weed control/
ditch bank areas in accordance with current terms and
i
conditions of registrations and commonly recognized practice
appear to outweigh the benefits of these uses. For these
reasons, I conclude that these uses of silvex appear to generally
cause unreasonable adverse effects on the environment [see
FIFRA Section 2(bb)] when used in accordance with widespread
and commonly recognized practice. Accordingly, I am hereby
initiating proceedings to cancel the registrations of all
pesticide products containing silvex registered for forestry,
rights-of-way, pasture, home and garden, commercial/ornamental
turf and aquatic weed control/ditch bank uses.
IV. PROCEDURAL MATTERS
This Notice initiates an action to cancel the
registrations of the forestry, rights-of-way, pasture,
home and garden, aquatic weed control/ditch bank, and
commercial/ornamental turf uses of silvex.— Under
Section 6(b) and 3(c)(6) of FIFRA [7 U.S.C. 136d(b); 7
U.S.C. 136b(a) (c)(5)J registrants and other interested
T7Other procedural matters relating to the emergency
actions are presented in the accompanying order suspending
the uses in question.
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persons may request a hearing on the cancellation actions
that this Notice initiates. This section explains th<2
prohibition against ex parte communications, when and how
affected persons may request a hearing, and the consequences o|
filing or of failing to file a request for a hearing in
accordance with the procedures specified in this Notice.—^
A. Ex Parte Communications
The Agency's Rules of Practice for hearings conducted
pursuant to Section 6 of FIFRA forbid the Administrator,
the Judicial Officer, and the Administrative Law Judge, at
all stages of the proceeding, from discussing the merits of
the proceeding ex parte with any party or with any person
who has been connected with the preparation of presentation
of the proceeding as an advocate or in an investigative or
expert capacity, or with any of their representatives. (40
CFR Section 164.7).
Accordingly, the following Agency officers, and the
staffs thereof, are designated to perform all investigative
and prosecutorial functions in this case: the Office of
4/ Although Section 6(b) of FIFRA generally requires prior
review of and comment upon proposed notices of intent to
cancel or change classification by the Secretary of Agricul-
ture and a Scientific Advisory Panel, I am specifically
authorized to waive such requirements and proceed in accord-
ance with Section 6(c) of FIFRA whenever I find that sus-
pension of a pesticide registration is necessary to prevent
an imminent hazard to human health. I have found that
immediate suspension of the registrations of pesticide
products containing silvex is necessary to prevent an
imminent hazard to human health (see Emergency Suspension
Order and Notice of Intent to Suspend Uses of SiIvex,issued
this day). I hereby invoke my authority to waive the
external review requirements. *
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Toxic Substances, the Office of Pesticide Programs, the
Office of General Counsel, and the Office of Enforcement.
From the date of this notice until any decision,
neither the Administrative Law Judge, the Judicial Officer
nor myself shall have any ex parte contact or communication
with any investigative or trial staff employee, or any
other interested persons not employed by EPA, on any of the
issues involved in this proceeding. However, persons
interested in this case should feel free to contact any
other EPA employee, including both investigative and trial
staff, with any questions they may have.
B* Procedures for Requesting a Hearing
(1) When a Hearing Must be Requested
for Cancellation Actions
Registrants affected by cancellation actions initiated
by this Notice may request a hearing within 30 days of
receipt of this notice, or within thirty days of the date of
publication of this notice in the Federal Register whichever
occurs later. Any person adversely affected by the cancel-
lation actions initiated by this Notice may request a
hearing within thirty days of the date of publication of
this Notice in the Federal Register.
(2) How t o Re q ue s t a Hearing
All registrants and other interested persons who
request a hearing must follow the Agency's Rules of Practice
Governing Hearings (40 CFR, Part 164). These procedures
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specify, among other things, that: (1) all requests for a
hearing must be accompanied by objections that are specific
for each use for which a hearing is requested [40 CFR
164.20(b)], and (2) that all requests must be received by
the Hearing Clerk within the applicable thirty (30) day
period [40 CFR 164.5(a)]. Failure to comply with these
requirements will automatically result in denial of the
request for a hearing.
Requests for hearings must be submitted to:
Hearing Clerk (A-110)
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
C. Consequences of Filing or Failing to
File a Hearing Request
If a hearing is requested on any cancellation action
on a silvex use initiated by this Notice before the end
of the 30-day notice period, the hearing will be governed by
the Agency's rules of practice for hearings under FIFRA
Section 6 (40 CFR, Part 164). In the event of a hearing,
the cancellation action(s) subject to the hearing will not
become effective except pursuant to orders of the Administra-
tor at the conclusion of the hearL
FEB 28 B?9
Date:
Douglas
Adoinis
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DECISION AND EMERGENCY ORDER SUSPENDING
REGISTRATIONS FOR CERTAIN USES OF
2-(2,4,5-TRICHLOROPHENOXY) PROPIONIC ACID (SILVEX)
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D. C. 20460
Office of Pesticide Programs
February 28, 1979
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Suspension Order
Registrations issued under the Federal Insecticide,
Fungicide and Rodenticide Act (FIFRA), as amended, 7 U.S.C.
Section 136 e_t. , seq. of all pesticide products containing
2-(2,4,5-trichlorophenoxy) Propionic Acid (Silvex) for the
forestry uses (including site preparation, conifer release,
and brush and weed control), rights-of-way uses (including
*/
brush and weed control), pasture uses— , home and garden
uses, commercial/ornamental turf uses (including recreational
area uses), and aquatic weed control/ditch bank uses are
hereby suspended and the sale, distribution, or other
movement in commerce, and the use of all such pesticide
products for the foregoing u^esj isf /prohibit ed.
Douglas/M.
Adminis
Date:
FEB 18 I979
JV Pasture is defined as land producing forage for animal
consumption, harvested by grazing, which has annual or more
frequent cultivation, seeding, fertilization, irrigation,
pesticide application, and other similar practices
applied to it. Fencerows enclosing pastures are included
as part of the pasture*
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Decision and Emergency Order Suspending Registrations for
Certain Uses of 2-(2,4,5-Trichlorophenoxy) Propionic Acid
(Silvex)
I. INTRODUCTION
During the past two years, the Agency has been
gathering information about the closely related phenoxy
herbicides, 2-(2,4,5-trichlorophenoxy) propionic acid
(silvex) and 2,4,5-trichlorophenxoy acetic acid (2,4,5-T),
as part of its Rebuttable Presumption Against Registration
(RPAR) process in order to decide whether the registration
of this pesticide should be continued. This review was
prompted by studies showing that silvex, 2,4,5-T, and/or
their dioxin contaminant, 2,3,7,8-tetrachlordibenzo-p-
*/
dioxin (TCDD)—' , caused reproductive and oncogenic effects
in test animals. During the public debate initiated by the
2,4,5-T RPAR (43 FR 17116, April 21, 1978), the Agency
received reports that women living in the vicinity of Alsea,
Oregon, had miscarriages shortly after 2,4,5-T was sprayed
in the forest areas where they reside. The Agency investiga-
ted the circumstances surrounding these reported miscarriages
*/ Current methods for manufacturing silvex produce TCDD as
a by-product of the manufacturing process. Although silvex
manufacturers attempt to remove this contaminant, TCDD
cannot be completely removed. An EPA contract laboratory
has measured the TCDD content in 8 recently produced
commercial samples of technical grade silvex from two
different manufacturers. The contractor reported that the
TCDD content in these samples ranged from 0.012 to 0.024 ppm
TCDD (limit of detection: 0.01 ppm). Therefore, because TCDD
is present as a low-level contaminant in commercial samples
of silyex, references in this document to "silvex" or the
"pesticide product" mean silvex that is contaminated with
TCDD.
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and compared the frequency of miscarriage in the Alsea area
with comparable data from a control area. The Agency has
concluded that the use of 2,4,5-T over a six-year period in
the Alsea area was related to a statistically significant
increase in the frequency of miscarriages by women residents
of the area, and that these miscarriages occurred shortly
after the use of 2,4,5-T in the area where these women
resided.
Based on this and other information, I am ordering
several emergency suspensions under FIFRA Section 6(c),
which halt the distribution, sale, and use of 2,4,5-T for
** /
forestry, rights-of-way, and pastures—' until the completion
*/
of further administrative proceedings.— Because both
silvex and 2,4,5-T are contaminated with TCDD, and because
of similarities in chemical structure, manufacturing processes,
use patterns, and effects in experimental systems, I consider
it prudent to take similar regulatory action against silvex.
I am therefore ordering emergency suspension of the forestry,
rights-of-way, and pasture uses of silvex because I find
that they pose an "imminent hazard" to humans and to the
**/ Pasture is defined as land producing forage for animal
consumption, harvested by grazing, which has annual or more
frequent cultivation, seeding, fertilization, irrigation,
pesticide application, and other similar practices applied to
it. Fencerows enclosing pastures are included as part of
the pasture.
^J For details, see the risk discussion in Section IV of
this document and the 2,4,5-T suspension document, published
simultaneously with this document.
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environment; I also find that an "emergency" exists because
there not enough time to hold a suspension hearing before
the next spraying season.
In addition, I am ordering the emergency suspension
of the home and garden, aquatic weed control/ditch bank, and
commercial/ornamental turf uses of silvex. These additional
uses of silvex are comparable to uses of 2,4,5-T cancelled
or suspended in 1970 because of concern that exposure to
2,4,5-T and/or TCDD posed an imminent hazard to humans and
to the environment. I now make similar findings of imminent
hazard for these uses of silvex. I also find that an
emergency exists relative to these uses because there is not
enough time to hold a suspension hearing before the spring
and early summer period of major silvex application for home
and garden, aquatic weed control/ditch bank, and commerical/
ornamental turf uses. In addition, I find that the year-round
application of silvex in certain areas of the country adds
to the urgency of the situation for the home and garden and
commereial/ornamental turf uses.
II. LEGAL AUTHORITY
A. Standards for Maintaining a Registration
In order to obtain a registration for a pesticide
under FIFRA, a manufacturer must demonstrate that the
pesticide satisfies the statutory standard for registration.
That standard requires (among other things) that the pesticide
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perform its intended function without "unreasonable adverse
effects" on the environment [FIFRA Section 3(c)(5)].
"Unreasonable adverse effect on the environment" means "any
unreasonable risk to man or the environment, taking into
account the economic, social and environmental costs and
benefits of the use of any pesticide" [FIFKA Section 2(bb)].
In effect, this standard requires a finding that the benefits
of each use of the pesticide exceed the risks of the use.
The burden of proving that a pesticide satisfies the regis-
tration standard rests with the registrant and continues for
as long as the registration remains in effect [Environmental
Defense Fund v. Environmental Protection Agency, 510 F.2d 1292,
1297 (D.C. Cir., 1975); Environmental Defense Fund v.
Environmental Protection Agency, 465 F.2d 528, 532 (D.C.Cir.,
1972)]. Under Section 6 of FIFRA, the Administrator is
required to cancel the registration, or change the classifi-
cation, of a pesticide whenever he determines that the
pesticide no longer satisfies the statutory standard for
registration.
B. Purpose and Standard for Suspending a Pesticide
The suspension provisions in Section 6(c) of the
statute give the Administrator authority to take interim
action until completion of the time-consuming procedures
required to reach final cancellation decisions. Under this
Section, the Administrator may suspend the registrations of
a product and prohibit its distribution, sale, or use during
cancellation proceedings upon a finding that the pesticide
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poses an "imminent hazard" to humans or the environment.
"Imminent hazard" is defined by the statute to mean that:
a
The continued use of pesticide during the
time required for cancellation proceedings
would be likely to result in unreasonable
adverse effects on the environment or will
involve unreasonable hazard to the survival of
a species declared endangered by the Secretary
of the Interior under Public Law 94-135.
As discussed above, "unreasonable adverse effects
on the environment" means that the risks from use of a
pesticide outweigh the benefits of its use. Thus, in order
to find an imminent hazard, it is necessary to find that the
risks of use during the period likely to be required for
cancellation proceedings appear to outweigh the benefits.
The Administrator may not suspend a pesticide without
having issued a notice of his intention to cancel the
registration, or to change the classification, of the
pestic ide.
Suspension is the Administrator's tool for quickly
correcting a situation which endangers public health. The
courts have repeatedly held that "the function of a suspension
decision is to make a preliminary assessment of evidence,
and probabilities, not an ultimate resolution of difficult
issues" [Environmental Defense Fund v. Environmental Protec-
tion Agency, supra, 510 F.2d at 1298]. "It is enough if
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there is a substantial 1 ike 1ihood [emphasis in original]
that serious harm will be experienced during the year or two
required in any realistic projection of the administrative
(cancellation) process" [Environmental Defense Fund, Inc. v.
Environmental Protection Agency, 510 F.2d 1292, 1297, (D.C.
Cir. 1975) quoting from Environmental Defense Fund, Inc. v.
Environmental Protection Agency, supra, 465 F.2d 540 (D.C.
Cir. 1972)]. Moreover, the registrant bears the burden of
proof during a suspension proceeding because, as indicated
above, the burden of proof under "FIFRA always resides with
the proponent of registration throughout the life of a
registration. (See, e.g., Environmental Defense Fund v.
Environmental Protection Agency, 510 F.2d at 1297; Environmen-
tal Defense Fund v. Environmental Protection Agency, supra,
465 F.2d at 532.)
C. Types of Suspension Proceedings
In this order, I have begun emergency suspension
proceedings. This is not the only type of suspension
provided in FIFRA. Section 6(c) provides for two kinds
of suspension proceedings: ordinary suspensions [FIFRA
Section 6(c)(2)J and emergency suspensions [FIFRA Section
6(c)(3)]. I have chosen to discuss both kinds of suspension
because the procedures applicable to each action are inter-
twined and because of the complexity of the suspension
provision as a whole.
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(1) Ordinary Suspensions
The Administrator may begin an ordinary suspension
when he finds that action is required to prevent an "imminent
hazard." An ordinary suspension is not effective immediately;
instead, the Administrator is required to give registrants
notice of his intent to suspend and to allow five days for
them to request a hearing. Only a registrant may request a
hearing. If a hearing is not requested within five days,
the suspension order becomes final and is not reviewable by
a court. If a hearing is requested, the Administrator is
required to convene an expedited proceeding at which other
interested persons can intervene. The sole issue at a
hearing is whether an imminent hazard in fact exists. The
procedures for conducting the hearing, with limited exceptions
discussed below, parallel the hearing procedures for an
emergency suspension. The Administrator decides whether to
affirm his imminent hazard determination at the conclusion
of the hearing; if he does, he issues a suspension order.
This order is accompanied by a notice of intent to cancel
the registration, or to change the classification, of a
pesticide (if one has not previously been issued). A final
order on suspension following a hearing is reviewable in the
Court of Appeals.
(2) Emergency Suspensions
Before issuing an emergency suspension order, the
Administrator is required to make two findings: (!) that
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the pesticide poses an "imminent hazard" and (2) that an
"emergency" exists. An "emergency" exists when the situation
"does hot permit [the Administrator] to hold a hearing
before suspending" IFIFRA Section 6(c)(3), 7 U.S.C. 136d(c)(3)]
The Agency interprets this statutory provision to mean that,
if the threat of harm to humans and to the environment is so
immediate that the continuation of a pesticide use is likely
to result in unreasonable adverse effects - i.e. the risks
outweigh the benefits - during a suspension hearing, the
registration of any product for that use may be suspended
immediately— .
An emergency suspension order is issued without
prior notice to registrants and takes effect immediately;
it remains in effect until the cancellation decision
if no expedited hearing is requested. If an expedited
hearing is requested on the issue of imminent hazard, the
emergency order continues in effect until the issuance of a
*y The term "emergency" is not defined by FIFRA, and
the statute in the emergency suspension section does not
specifically require the Agency to balance benefits against
health and environmental risk of pesticide use. An alter-
native reading would be that an emergency exists whenever a
serious risk could result from pesticide use during the time
for conducting a suspension hearing. However, for the
purpose of this proceeding I have decided to consider the
risks and benefits in ordering an emergency suspension, just
as I balance risks and benefits in deciding whether to
register a pesticide or to take the pesticide off the market
through a cancellation or ordinary suspension order. FIFRA
is a risk/benefit statute, and I see no reason to depart
from this balancing test in issuing emergency suspension
orders .
_ 0_
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final suspension order. Registrants are given five days to
request an expedited hearing. The hearing stage is to begin
within five days of the Agency's receipt of the hearing
request. Unlike the ordinary suspension situation, no party
other than the registrant and the Agency may participate in
the expedited hearing on the emergency order, except to file
briefs. The procedures for conducting the hearing are
otherwise the same as in an ordinary suspension. For both
types of suspension, the hearing is to be conducted in
accordance with 5 U.S.C. Section 554.556 and 557 except that
the presiding officer need not be a certified hearing
examiner. For both types of suspension, the presiding
officer shall have ten days from the conclusion of the
presentation of evidence to submit recommended findings and
conclusions to the Administrator. The Administrator shall
then have seven days to issue a final order on the issue of
suspension.
FIFRA provides for a special appeal of an emergency
suspension order to the District Court. If an administrative
hearing is requested, an emergency suspension order is
subject to immediate review in District Court by the regis-
trant or by other interested persons with the registrant's
consent. On the other hand, if no request for a hearing
before the Agency is made, the emergency order becomes
final and is not reviewable by any court [FIFRA Section
6(c)(2), 6(c)(3)]. The District Court action may occur
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simultaneously with the suspension proceeding before the
Administrator.
The District Court reviews only whether the emergency
finding is supported. The standard for review by the
District Court is very narrow—whether the order of suspension
is "arbitrary, capricious, or an abuse of discretion, or
whether the order was issued in accordance with the procedures
established by law" iFIFRA Section 6(c)(4)]. If the District
Court finds against the Agency, it may stay the suspension
order until completion of the expedited suspension hearing.
The District Court order may be appealed to the
Appellate Court by either the Agency or the registrant,
depending on the outcome. A final order on suspension,
after a hearing before the Agency, may be reviewed in the
Court of Appeals on an expedited basis even though related
cancellation proceedings may not have been completed.
III. SUMMARY OF FINDINGS
A. Summary of Findings on Risk
Numerous studies have clearly demonstrated that TCDD
and/or silvex contaminated with TCDD can produce fetotoxic,
teratogenic, and carcinogenic effects in experimental animals
which have been exposed to these chemicals. I find that the
occurrence of these effects in test animals indicates that
humans who are exposed to TCDD and/or silvex may experience
comparable effects.
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A recent epidemic logical study reported that women
living in the vicinity of Alsea, Oregon (an area where
2,4,5-T and silvex were extensively used),— have a
statistically significant higher incidence of spontaneous
abortions (miscarriages) than women living in a control
area. Specifically, the study shows that:
(1) The spontaneous abortion index for the Alsea
Study area where 2,4,5-T is used is significantly higher
than the index for urban or rural control areas where there
is little or no known use of 2,4,5-T.
(2) There is a significant increase in the abortion
index in the study area relative to the control area in the
months of June and July. This increase follows by approxi-
mately two months a period in March and April when 2,4,5-T
is used to control vegetation in the forested areas in which
these women live.
(3) Statistical analyses of these data indicate that
there is a significant correlation between 2,4,5-T used in
the study area during the spraying season and the subsequent
increase in the spontaneous abortion index in the study.
This relationship between exposure to 2,4,5-T
spraying and an increased incidence of miscarriages in
humans is not surprising. This is the same relationship
that has been demonstrated to exist in test animals through
^7Althoughthe study addressed only 2,4,5-T usage, it
is now known that silvex was also used in the Alsea area
during the period of the study.
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numerous animal studies. While there are uncertainties
concerning the amount of 2,4,5-T and/or TCDD to which
Vjrmu. Kflv& bitty}
the Study area women' w-ep«~~ e x:p o s e d and concerning the
precise route (or routes) of human exposure, the statis-
tically significant incidence of miscarriages described
above makes it prurleB-t for the Agency to conclude that
these women in the Alsea study area were exposed to 2,4,5-T.
In addition, because of the relative toxicities of 2,4,5-T
and TCDD, the Agency concludes that it is reasonable
to assume that any adverse reproductive effects attributable
to low-level exposure to 2,4,5-T are primarily due to
its contaminant, TCDD. Since silvex contains TCDD, the
Agency may reasonably assume that exposure to silvex may
also cause adverse reproductive effects.
Therefore, the Agency concludes that it is also
reoscoab/e-
prudent to assume that individuals may be exposed to silvex
and/or TCDD who frequent or live in areas where silvex is
used in ways and under conditions which may cause them to
experience exposure opportunities qualitatively similar
to those experienced by the Study area women. The Agency
has concluded that silvex use patterns involving exposure
opportunities qualitatively similar to those experienced
by the Study area women are the forestry, rights-of-way,
pasture, home and garden, commercial/ornamental turf and
aquatic weed control/ditch bank uses of silvex. The Agency
has identitfied pesticide applicators and persons involved in
pesticide application support activities, and persons living
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in or frequenting, areas of silvex use as the principal
groups of individuals who may be exposed as a result of the
forestry, rights-of-way, and pasture uses of silvex. Based
upon the animal test data and other information, including
the Alsea study, the Agency has concluded that individuals
exposed to silvex and/or TCDD may experience adverse
reproductive effects and cancer. Accordingly, the Agency
concludes that it is prudent to regard individuals who may
experience exposures qualitatively similar to those
experienced by the Study area women as a result of the
forestry, rights-of-way, pastures, home and garden,
commercial/ornamental turf and aquatic weed control/ditch
bank uses, as individuals who may suffer reproductive
effects or cancer as a result of these uses of silvex.
B. Summary of Finding_g_ on. Benefits During the
Cancellation Proceedings
The suspended uses (forestry, rights-of-way, pastures,
home, aquatic weed controI/ditch bank, and commercial/ornamental
turf) comprise about 67% of the estimated 2.8 to 3.3 million
pounds of silvex used in the United States.
I find that the economic impact of either an initial
3 1/2 month emergency suspension or a 2-year suspension
will be insignificant, based on several considerations.
The inherent flexibility in the tratment schedules permits
delays in treatment during the suspension period. Alternative
chemicals, mechanical, and manual control treatments are
available and are currently being used. Even though these
alternatives may not generally be as cost-effective as
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silvex, their availability will minimize the impacts of
the suspension period. The major significance of a silvex
suspension is that silvex would not be available for more
extensive use on forest and pasture sites as an alternative
for 2,4,5-T.
(1) Forestry
Use of silvex in forestry is primarily for release
of young conifers and site preparation activities. However,
silvex is not widely used because of its relatively limited
control spectrum and toxicity to pines. The only extensive
forestry use of silvex in recent years has been by the
Bureau of Land Management in Western Oregon. (Use of
2,4,5-T and picloram was prohibited or restricted by the
Interior Department in 1970).
Several chemical, mechanical (including controlled
burning) and combination methods are available as alternatives
for site preparation. Only silvex, 2,4,5-T and 2,4-D are
preferred for the release of conifers; however, for this
purpose 2,4-D has the most limited control spectrum. Manual
methods are also available for release activities.
I find that the suspension of the forestry uses of
silvex for a 3 1/2 month or 2-year period would not have any
significant economic impact, because the principal past users,
the United States Department of the Interior and Forest Ser-
vice, have recently almost completely discontinued use of the
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herbicide. Both agencies have already absorbed the additional
costs of using alternatives.
(2) Rights-of-way
Silvex is used to control woody and herbaceous plants
on railroads/ highways, electric transmission lines and
pipelines. Chemical, mechanical and manual methods of control
are often combined for use on rights-of-way acreage, with
manual and mechanical methods the most commonly used.
If silvex were not available, users would use alternative
herbicides, since combinations of these provide equivalent
control, and are cheaper than silvex. Therefore, I find
that suspension of silvex use for 3 1/2 months or two years
on rights-of-way would have no economic impact.
(3) Pasture
Silvex weed control in pastures is now practiced
on only a very small proportion of the nation's pasturelands.
Generally, users prefer other chemical herbicides to silvex
for use in pastures. There are effective chemicals and/or
mechanical control alternatives, although these alternatives
may be more expensive than silvex.
If silvex were not avaiable, current users would
probably adopt one of the alternative herbicides. In so
doing, their incomes may be reduced by the small additional
cost of using the alternative. I find that this impact of
a 3 1/2 month or 2-year suspension would be nominal.
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C4) Commercial/Ornamental Turf
Silvex use on ornamental turf (golf courses, parks,
athletic, fields, etc.) may be as high as two million pounds.
Use on golf courses is extensive. Silvex is generally
applied in combination with other herbicides. Use of
combinations of the same herbicides, without silvex, is
estimated to be as effective and comparably priced.
Without silvex, users would shift to the readily
available alternatives. I find that the economic impacts on
this group of users would be minimal if silvex were suspended
for 3 1/2 months or two years.
(5) Home and Garden
Most homeowner use of herbicides in the United States
is for control of weeds in lawns. Less than 25% of the
U.S. homeowners use herbicides. As with use on commercial/
ornamental turf, silvex is usually used on lawns in com-
binations with other herbicides. These combinations are
considered equally as effective without silvex, and
comparatively priced.
If silvex were no longer available, homeowners
would switch to the alternative combinations. I find that
the impact of suspension for 3 1/2 months or two years would
be negligible.
(6) Aquatic Weed Control/Ditch Bank
Silvex is used to control aquatic weeds in static
water areas used for recreation and in farm ponds used for
watering livestock. It controls submerged, emerged and
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floating weeds. Essentially all weeds controlled by this
use of silvex are sensitive to other aquatic herbicides or
biological agents.
Silvex is also applied to drainage ditch banks and
canal levees. Although there are no known chemical alternatives
for control of a few of the weed pests found in these areas,
there are registered chemicals which are effectve against
many of them. Manual and mechanical methods are also
avail able.
I find that the suspension of silvex for 3 1/2 months
or two years would not be a significant economic burden on
users for control of weeds in static bodies of water,
because of the availability of effective, economical alterna-
tives. The effect of a suspension on ditch/canal users
would be somewhat greater because of the resistant weeds.
Nonetheless, I find that the impact of the suspension of
silvex would be nominal.
C. Summary of Findings on Imminent Hazard
(1) Forestry Use
In order to find an imminent hazard, I must find that
the risks of use during the period likely to be required for
cancellation proceedings appear to outweigh the benefits.
The Alsea study, establishing correlation between use of
2,4,5-T in forest management and miscarriages in humans,
coupled with animal studies showing similar effects, indicates
that there is a substantial likelihood that serious harm
could result to persons with qualitatively similar exposure
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from the forestry use of 2,4,5-T. Because of the high
probability that the adverse effects attributable to low
levels of 2,4,5-T are primarily due to its TCDD contaminant,
comparable exposure to the TCDD contaminant in silvex would
result in similar risk potentials.
At this point, because of the voluntary discontinuation
of the forestry uses of silvex by the major users, there
appear to be no risks or benefits of its use during a
cancellation proceeding. However, since forestry use of
2,4,5-T is being suspended, the real possibility of the
reinstatement of silvex must be considered. In that event,
I conclude that the risks of the forestry uses of silvex
outweigh the benefits. The economic impacts of suspension
would be small because of the flexibility of treatment
schedules and the availability of alternatives. Hence, I
find that an imminent hazard exists for the forestry use of
siIvex.
(2) The Rights-of-Way Use
The use patterns of silvex for rights-of-way use
create the same, or greater, potential for human exposure as
the forestry use. Hence, the rights-of-way use results in a
hazard to human health which in my judgment outweighs the
corresponding benefits. A use moratorium during the
cancellation proceedings would not have a significant
economic impact because many rights-of-way managers are
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likely to use alternate chemicals which are available and,
taken as a whole, are relatively similar in cost and effec-
tiveness. Therefore, I find that an imminent hazard exists
for the rights-of-way use of silvex during the cancellation
proceedings.
(3) Pasture Use
The use of silvex on pastures results in a lower
potential for exposure than the use of silvex in forestry
because silvex is applied in pastures for spot treatment by
knapsack spraying equipment. The forestry use involves
substantial application by aerial methods., which have a
greater potential for creating drift than does ground
equipment.
The benefits of pasture use of silvex are marginal.
Silvex weed control is practiced on a very small portion
of pasture acreage, showing the relative unimportance
of the chemical for this purpose. Moreover, there are
effective chemical and/or mechanical control alternatives.
Hence, it is readily apparent that the risks to human
health outweigh the benefits of use during the cancellation
proceeding. Accordingly, I find that the use of silvex on
pastures results in an imminent hazard.
(4) Commercial/Ornamental Turf
The use of silvex on commercial and ornamental turf
creates the potential for the same, or greater, exposure to
humans as the forestry use, and therefore presents a compar-
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able hazard to human health. Although use on commercial and
ornamental turf represents the largest single use of silvex,
a suspension of this use would not have a significant
economic impact. Users would switch to readily available,
effective, economical alternatives. Therefore, I find that
an imminent hazard exists for commercial/ornamental turf
uses of silvex during the cancellation proceedings.
(5) Home and Garden Use
If the forestry use of silvex creates a potential
health hazard for humans, the home and garden use has an
even greater hazard potential. In home application, there
are the additional problems of hand application by a non-
professional, unlimited application frequency and rates, and
high probability of bystanders. The available alternatives
to silvex for home and garden use are effective and economical,
Because the potential risks from home and garden use of
silvex during the course of a cancellation proceeding
far outweigh any of the benefits of its use, I find that an
imminent hazard exists relative to this use.
(6) Aquatic Weed Control/Ditch Bank
Silvex use for the control of aquatic weeds has the
potential for human exposure equal to or greater than that
likely from forestry use. In addition to the exposure
possibly resulting from the actual application of the
herbicide, there is the possibility of exposure from contact
with the treated water. The suspension of the aquatic uses
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of silvex for static bodies of water would have no significant
economic impact, because of the availability of alternatives;
the suspension of uses for drainage ditch banks and canal
levees would result in a nominal economic impact. Nevertheless,
when viewed as a whole, I find that the potential risks of
these uses outweigh the benefits. Therefore, I find that an
imminent hazard exists for the period of the cancellation
proceeding relative to these uses.
D. Summary of Findings on Emergency
As previously discussed, I have interpreted the
statutory provision on emergency suspensions [FIFRA Section
6(c)(3)] to require a preliminary balancing of risks against
benefits of use during the time for holding a suspension
hearing. Hence, an emergency finding involves two issues:
(1) immediate intervention is required because there is not
time to hold a suspension hearing before the next period of
pesticide use; and (2) the risks outweigh the benefits
during the time for holding the suspension hearing. At the
end of the suspension proceeding, I have discretion to
affirm, modify, or reverse my suspension order.
(1) Forestry Use
There is not enough time to hold a hearing before
the next forest spraying season. The next spray season
begins in March. I am advised that in some parts of the
Pacific Northwest, spraying is about to begin or has already
begun. Hence, assuming silvex use on forests poses unreason-
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able adverse effects, immediate action is required to stop
silvex use.
The risks posed by silvex forestry use clearly
outweigh the benefits of use during the suspension proceeding
which is anticipated to run from March through June (see
discussion in Section V below). The Alsea study suggests
that persons in the vicinity of forest spray are being
exposed to TCDD-containing herbicides, and consequently
suffer a potential risk from their use. Many scheduled
silvex treatments can be deferred for the duration of
cancellation proceedings. Therefore, those treatments can
be deferred during the suspension proceedings. In any case,
alternatives are often available for use in areas where
treatment is deemed essential.
Accordingly, I find that an emergency exists for the
forestry use of silvex. Therefore, I am ordering immediate
suspension of all silvex registrations for these uses of
silvex.
(2) Rights-of-Way Use
Silvex is applied on rights-of-way (railways, highways,
electric transmission lines, and pipelines) during the
spring growth season, which is due to start in March in some
parts of the courntry. Additionally, some methods of
application may be year-round. Hence, there is not enough
time to hold a suspension hearing before the period of
maximum use of silvex on rights-of-way.
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The risk of silvex use outweighs the benefits during
the time for holding the suspension proceedings. As indicated
earlier, silvex poses a severe health risk to people living,
working, or passing through affected rights-of-way areas;
on the other hand, the benefits of use during the suspension
proceedings are very small. On areas scheduled for treatment,
treatment can generally be postponed for the anticipated
3 1/2 month duration of a suspension proceeding. Incremental
growth during the time required to hold a suspension hearing
is unlikely to be so great that treatment could not be
deferred. Furthermore, there are effective and economical
alternatives for the small number of instances where weed
growth would interfere with equipment or endanger the safety
of a system's users.
Accordingly, I find that an emergency exists for the
rights-of-way use of silvex. Therefore, I am ordering an
immediate suspension of all silvex registrations for the use
of silvex on rights-of-way.
(3) Pasture Use
The application of silvex to restrict weed growth
on pastures is expected to occur in March in some parts
of the country and in even more areas before the anticipated
completion of the suspension proceeding in June. Hence,
emergency measures are required to prevent human exposure to
silvex from pasture use during the suspension hearing.
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As previously noted, the risk to humans from silvex
use on pastures is roughly comparable to the risk to people
in treated forest areas. On the other hand, the benefits of
use during the 3- to 4-month suspension period are virtually
nil. Treatment can most certainly be postponed during
this short period. In any case, there are effective chemical
and/or mechanical control alternatives which can be used in
areas where treatment cannot be postponed.
Accordingly, I find that an emergency exists for the
pasture use of silvex. Therefore, I am ordering immediate
suspension of all silvex registrations for the use of silvex
on pastures.
(4) Commercial/Ornamental Turf
Silvex is usually applied to commercial and ornamental
turf during the spring and fall seasons. Therefore, a
period of heavy usage is now pending. Moreover, in some
areas of the country, use can be expected to be year-round.
There is not enough time to hold a suspension hearing before
the period of maximum use of silvex on commercial and
ornamental turf.
The potential risks to human health from the use
of silvex on commercial/oraniental turf outweigh the benefits
of use during the time necessary to hold a suspension
proceeding. As indicated above, the use of silvex on
ornamental turf during this period, would pose at least the
same hazard as forestry use for a similar period. The
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benefits of use during the time required for a suspension
proceeding would be minimal. In most cases where treatment
was necessary during this period, users would switch to
alternatives which are effective and comparably priced.
Accordingly, I find that an emergency exists for the
use of silvex on commercial/ornamental turf. Therefore, I
am ordering an immediate suspension of all silvex registra-
tions for the use of silvex on commereial/ornamental turf.
(5) Home and Garden
Home and garden use of silvex normally occurs in the
spring and fall. However, as in commercial/ornamental turf
use, application could be year-round in some areas of
the country. Therefore, because of the nearness of a
major usage period, and the probability of continuous use
in certain sections of the country, emergency measures are
necessary to prevent possible substantial human health
hazards during the course of the suspension hearing.
As previously indicated, the potential threat to
humans is probably greater from the home and garden use of
silvex than from its forestry use. The fact that use of
silvex by homeowners is almost entirely aesthetic, rather
than for other purposes, indicates that the economic benefits
of their use are marginal at any time. For the few areas
where some control method may be necessary during the period
of the suspension proceeding, effective and economical
alternatives are available.
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Accordingly, I find that an emergency exists for the
home and garden uses of silvex. Therefore, I am ordering an
immediate suspension of all silvex registrations for this
purpose.
(6) Aquatic Weed Control/Ditch Bank
The application of silvex to restrict aquatic weed
growth is generally begun in the spring and continued
through early summer. Hence, there is insufficient time to
hold a suspension hearing before humans are exposed to the
potential risks to their health due to this use of silvex.
The potential human risks from the aquatic use
of silvex during the suspension hearing clearly outweigh
the benefits of use during that limited period. The human
health hazard is at least as great as that from forestry
use. The benefits to be derived from the aquatic use of
silvex during a suspension hearing are very small. In most
instances, the use of any herbicide could be deferred for
this short period of time. However, for static water areas
where some herbicidal use would be necessary, there are
available chemical alternatives; for the few drainage ditch
and canal levee areas which contain pests resistant to
chemical alternatives, manual methods could be used.
Accordingly, I find that an emergency exists for
the aquatic weed control/ditchbank use of silvex. Therefore,
I am ordering an immediate suspension of all silvex registra-
tions for these purposes.
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IV. DETAILED FINDINGS CONCERNING IMMINENT HAZARD AND EMERGENCY
In Section III of this notice, I have presented a
summary of my findings that an imminent hazard and emergency
• ^ *. Ifl-fld qqfcc
exist for the forestry, right s-of-way, pasture, homejf^ IT
aquatic weed control/ditch bank, and commercial/ornamental
turf uses of silvex. The data, information, and analyses
upon which these findings are based are detailed below.
A. Findings Relating to Adverse Effects in Test
Animals
(1) Adverse Reproductive Effects in Test Animals
This section presents the test animal data upon
which I relied in finding that exposure to TCDD and/or
silvex is likely to result in adverse reproductive effects
in humans. Except as specified below, these data were
derived from studies in which pregnant rodents or primates
were orally exposed to the test substance during the
second trimester of the gestational period. The pregnant
rodents were sacrificed shortly before parturition, and
live fetuses were examined for abnormalities. The Agency
has extracted key data for presentation in this report
of findings. Experimental details and descriptions of the
underlying data are available in the 2,4,5-T RPAR notice and
in the published literature.
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(a) Exposure of Test Animals to TCDD
TCDD produces fetotoxic effects such as death
and reduced fetal size; skeletal deformities such as cleft
palate and clubfoot; injury to internal organs such as
intestinal bleeding, intestinal lesions, and abnormal
kidneys; and post-partum effects such as reduced survival.
These effects appear in several different rodent strains and
species, occur in all of the litters in some dose groups,
^3±J&S5JL)
and occur at doses Jas low as 0.01 ug TCDD/kg. The repeated
and regular appearance of several different forms of damage
to test animals of several different strains and species
indicates that TCDD is a teratogenic and fetotoxic agent in
mammals.
(i) Fetotoxic and Embryolethal Effects
Fetotoxic and embryolethal effects have been reported
for at least three different mouse strains, two different
rat strains, and one strain of subhuman primates exposed to
TCDD during gestation. For example, in studies using
generally low-dose regimens of TCDD, Neubert and Dillmann
reported that resorption sites (resorbed or dead embryos)
occurred in 54% (7/13) of the litters at 0.3 ug/kg and in
100% (3/3) of the litters at 9.0 ug/kg for NMRI mice,
compared to 24-32% (23/95 and 24/65) of litters exhibiting
resorptions in control animals which had not been exposed to
TCDD. Sparschu et al. reported resorption of 100% (110/110)
of the fetuses in Sprague-Dawley rats exposed to 8 ug
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TCDD/kgf compared to 20% resorption (63/309) of the fetuses
from the control animals. Khera and Ruddick reported 100%
(77/77) resorption of fetuses at 4 ug/kg and 36% (56/153) at
exposures of 1 ug/kg in Wistar rats, compared to 2-7% (3/152
and 10/127) in the control animals. Smith et al. reported
resorptions in 95% (18/19) of the litters of CF-1 mice
exposed to 1.0 ug/kg, compared to 74% (25/34) in the control
animals; despite the high control incidence of resorptions
in this study, the increased incidence in the experimental
animals was statistically significant. In an abstract of a
current study, Schantz et al. (1979) reported 57% (4/7) of
pregnant monkeys aborted and one delivered a stillbirth.
Two others on the 50-ppt diet failed to conceive, and two
delivered normally. The eight control animals all delivered
normal infants. Maternal toxicity was observed in some dose
groups in some of these studies.
Similar effects have been reported at higher dose
levels of TCDD. Neubert and Dillmann reported that a single
dose of 45 ug/kg to NMRI mice on day 6 produced resorptions
in 100% (3/3) of the viable litters, compared to resorptions
in 24% (23/95) of the control litters. Courtney reported
an average of 87% mortality in 6 litters of CD-I mice orally
exposed to 200 ug/kg, compared to an average mortality of 6%
in 15 vehicle control litters. This investigator also
reported an average of 76% mortality in 6 litters of CD-I
mice exposed subcutaneously to 200 ug TCDD, compared to 14%
-29-
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in the six litters of control animals. Some of these
studies also describe statistically significant weight
depression in the surviving embryos (e.g., Sparschu et al.).
These and other studies also report that TCDD had no
measureable adverse effects at some dose levels in some
strains. For example, Khera and Ruddick report no fetotoxic
effects at 0.125 ug/kg in Wistar rats, and Neubert and
Dillmann report no teratogenic effects at 0.3 ug/kg in NMRI
mice. Courtney and Moore reported that TCDD had no effect
on fetal weight or embryonic mortality at 0.5 ug/kg in CD
rats, and Sparschu et al. reported no effect at 0.03 ug/kg
in Sprague-Dawley rats.
Dow Chemical Company, a silvex registrant, has
recently completed a study of the effects of TCDD on re-
production in Sprague-Dawley rats exposed to low dose levels
of this chemical for three generations. The registrant
concluded that "impairment of reproduction was clearly
evident among rats ingesting 0.01 or 0.1 ug TCDD/kg/day.
Significant decreases were observed in fertility, litter
size, gestation survival, post-natal survival and postnatal
body weight." In addition, exposure to 0.001 ug TCDD/kg
per day resulted in statistically significant increases in
-30-
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per day resulted in statistically significant increases in
the percentage of pups dead at birth and/or dying before the
end of three weeks of life in some generations.—
Although the experimental protocols and strains
differ for the several studies cited, in each case TCDD
lor-
significantly increased the incidence of resorbed embryos f
relative to the rate observed in control animals not exposed
to TCDD. The regular occurrence of embryonic death in
studies by different investigators in primates and in
different rodent strains indicates that exposure to TCDD
during mammalian gestation may result in the death of the
embryos and related maternal reproductive failure.
( i i ) Skeletal Anomalies
Skeletal defects appear in six studies involving four
different mouse strains. Courtney and Moore report the
following incidences of cleft palate in the indicated
*_l Dow Chemical Company has claimed that the results
of this study are "trade secret" or "confidential." An
injunction issued on April 4, 1978, in the case of Dow
Chemical Co. v. Costle, Civil Action No. 76-10087, U.S.
District Court for the Eastern District of Michigan (Northern
Division), arguably precludes EPA from disclosing the data
from this study at the present time. Although the relevant
provisions of FIFRA have since been amended to allow disclo-
sure of data such as this [see, e.g., FIFRA Section 10(d)
and 10(g)J, the injunction has not yet been modified. EPA
intends to promptly request the Court to modify the injunction,
but until this has been done the Agency will not publicly
disclose the data from the study. The summary presented in
the text of this Order does not, in EPA's opinion, constitute
disclosure of the allegedly "trade secret" data submitted by
Dow and would not cause any harm to Dow's legitimate competi-
tive interests. The data from the study may be made available
to any party in a suspension or cancellation proceeding
under an appropriate protective arrangement.
-31-
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strains exposed to 3 ug/kg TCDD: 71% (5/7) in litters of
\
C57BL/6 mice, compared to none (0/23) in the controls; 22%
(2/9) in litters of DBA/2 mice compared to none (0/23) in
the controls; and 30% (3/10) for CD-I mice, compared to none
(0/9) in the controls. Neubert and Dillmann, also using 3 ug
TCDD/kg, reported 29% (7/24) of the viable litters had
fetuses with cleft palate for NMRI mice compared to 6%
(10/160) of the control litters. Smith et al. reported
cleft palate in 71% (10/14) of CF-1 mouse litters at 3
ug/kg, compared to none (0/34) in the controls.
In exposures of shorter duration, Moore et al.
reported cleft palate in 86% (12/14) of C57BL/6 mouse
litters exposed on days 10-13 to 3 ug/kg, compared to none
(0/27) in the control litters. Neubert and Dillmann reported
cleft palate in 71% (10/14) of litters of NMRI mice exposed
to a single 45 ug/kg dose on day 11, compared to 6% (6/95)
of litters in the controls.
Courtney and Moore reported no cleft palate in any of
the litters in CD rats exposed to 0.5 ug/kg. Similarly,
Khera and Ruddick, using Wistar rats, reported that the
occurrence of the skeletal anomalies in the fetuses exposed
to 2.0 ug/kg was comparable to the rate for the untreated
animals.
(iii) Injury to Internal Organs
Exposure to TCDD produced injury to the kidneys and
intestinal tracts of at least five different mouse and rat
-32-
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strains. Smith et al. reported 28% (4/14) of litters with
kidney anomalies at 3 ug/kg in CF-1 mice, compared to none
(0/34) in the controls. Moore et al. reported 100% (14/14)
of litters with kidney anomalies in C57BL/6 mice exposed to
3 ug/kg on days 10-13, compared to none (0/27) in the
control litters. Courtney and Moore reported kidney anomalies
in 100% (10/10) of the litters of CD-I mice at 3 ug/kg,
compared to 33% (3/9) in the controls, and 67% (4/6) litters
with abnormal kidneys in the CD rat at 0.5 ug/kg as compared
to none (0/9) in the control litters. Sparschu et al.
reported hemorrhages or lesions in the intestine of 36%
(36/99) of the fetuses of Sprague-Dawley rats exposed
to 0.5 ug/kg, compared to none (0/246) in the control
fetuses.
(b) Exposure of Test Animals to Silvex
Silvex has been shown to produce fetotoxic effects
such as fetal mortality, reduced body weight, skeletal
anomalies, and injury to internal organs. The effects
have been observed in test rodent species at maternal
doses as low as 50 mg/kg (TCDD < 0.05 ppm). These results
clearly indicate that silvex is fetotoxic and teratogenic
in mammals.
Courtney— reported significant incidences of
increased fetal mortality and reduced fetal weight in CD-I
*7Courtney, K.D. 1977. Prenatal effects of herbicides:
evaluation by the prenatal development index. Arch. Environ.
Contam. Toxicol. 6(1):33-46.
-33-
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mice which had received prenatal exposure to silvex.
Maternal subcutaneous exposure to 405 mg/kg silvex (TCDD <
0.1 ppra) resulted in 25% (33/132) fetal mortality and an
average fetal weight of 0.87 g, compared with control values
of 12% (19/171) and 1.03 g, respectively. Oral exposure to
the same dose resulted in an average fetal weight of 0.83 g,
compared with 1.01 g in the controls. An increased incidence
of cleft palate was also observed among the treated fetuses.
Oral exposure resulted in an incidence of 7% (7/95); subcuta-
neous exposure resulted in 3% (3/99). No cleft palates
(0/260) were observed among the control animals.
Dow Chemical Company—' studied the reproductive
effects of silvex and the propylene glycol butyl ether ester
of silvex (silvex-PGBE), each containing less than 0.05 ppm
TCDD. Sprague-Dawley rats were exposed to 25 to 100 mg/kg on
days 6 through 15 of gestation. Significant effects on
fetal mortality and birth weight were observed in the
litters of treated dams. Skeletal anomalies, such as cleft
palate, retarded ossification, and extra cervical ribs were
observed among the exposed fetuses. Micropththalmia (abnormal
smallness of the eyeball) and circulatory system abnormalities
were also-seen. Similar effects were observed when animals
were dosed with silvex-PGBE, or when dosed for three-day
intervals during the period of early organogenesis.
Dow Chemical Co. has also requested confidentiality
for the results of this study. The discussion in the
footnote in Section IV.A.(1)(a)(i) of this document
applies to these data.
-34-
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In each of the studies cited above, some maternal
toxic effects were observed. Courtney found increased
maternal weight gains and increases in liver to body weight
ratios among the treated groups; Dow noted baldness (alopecia),
lack of appetite and vaginal bleeding. However, the existence
of maternal toxic effects does not negate the impact of the
observed injury to and death of the fetus.
(2) Oncogenic Effects in Test Animals; Exposure of
Test Animals to TCDD
The Carcinogen Assessment Group (CAG) has concluded
that TCDD induces carcinogenic responses in mice and rats
at exceedingly low dose levels and that these effects,
together with data showing that TCDD is mutagenic, con-
stitute substantial evidence that TCDD is likely to be
a human carcinogen.
Dow Chemical Company, a silvex registrant, studied
the effects of TCDD on male and female Sprague-Dawley
rats exposed to 0.022, 0.220, or 2.2 ppb TCDD. CAG
agrees with the registrant's conclusion that there is a
statistically significant increase in the incidence of
heapatocellular carcinoma in female rats exposed to 2.2 ppb
TCDD. In another study using Sprague-Dawley rats, Van
Miller reported that 1 ppb and 5 ppb TCDD produced a carcino-
genic response in the livers of male Sprague-Dawley rats.
These observations tend to confirm the registrant's observa-
tions that TCDD produces an oncogenic response in the livers
-35-
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** /
of male Sprague-Dawley rats.—Further, a preliminary
report of a not-yet-completed National Cancer Institute
study tends to confirm these observations of a carcinogenic
response in rats. A contractor for the National Cancer
Institute has reported that TCDD is carcinogenic in the rats
and mice used in that study.
CAG also emphasized that, at low levels/ TCDD is
a potent inducer of arylhydrocarbon hydroxylase, an enzyme
system that contains an enzyme that is known to mediate
the formation of epoxides, compounds which are potentially
active carcinogenic metabolites.
CAG also reported that TCDD is mutagenic in the
Ames test without the metabolic activation system. Its
mutagenic activity is exhibited by frameshift mutations
caused by intercalation between base-pairs of DNA.
B. Findings Relating to Risk to Humans
(1) Study of Miscarriages in Alsea, Oregon
The Alsea study detailed below was performed taking
into consideration only 2f4,5-T applications during the
reference period. Information has recently become available
to the Agency which documents the use of silvex in the
**/ The CAG and an EPA audit found that this study had
major shortcomings in design and conduct that limited the
reliability of the data developed at dose levels lower than
1 ppb.
-36-
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* /
Alsea area during the period of time studied.— However,
even without this information, I would have found that the
serious implications of this study are as applicable to
silvex as to 2,4,5-T. TCDD, the contaminant contained in
both herbicides, is a potent mammalian fetotoxin and teratogen
at very low doses. Conversely, silvex and 2,4,5-T are
fetotoxic and teratogenic at comparatively high doses. It
is reasonable to assume that the adverse human reproductive
effects observed in Alsea which have been attributed to
low-level exposure to 2,4,5-T are due primarily to the TCDD
in the 2,4,5-T. Therefore, since silvex also contains TCDD,
I conclude that the Alsea data are applicable to areas where
silvex is used when evaluating potential reproductive risk
to humans.
(a) General Discussion
In response to the 2,4,5-T RPAR notice, a group
of eight women informed the Agency that they lived within 12
miles of Alsea, Oregon, where 2,4,5-T and silvex are used in
forest management and that they had experienced a total of
13 miscarriages between 1972 to 1977. In their letter, the
women presented information showing that most of their
*7Herbicidespray records for Alsea basin, 1972-1978
TEPA 1979). Use of silvex was also claimed by the women in
the 2,4,5-T RPAR response which prompted the Alsea study
[2,4,5-T RPAR rebuttal comment, 30000/26:#363].
-37-
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miscarriages occurred eight to ten weeks after conception
and followed by four or six weeks the date of the spring
application of 2,4,5-T in the forest areas in which these
women reside. The women indicated their belief that this
information suggested that the unusually high number of
miscarriages in their group was related to the use of
2,4,5-T and/or silvex.
The effects which these women reported were comparable
to the embryolethal and fetotoxic effects observed in
test animals that have been exposed to 2r4,5-T and/or TCDD.
Moreover, because embryos are particularly susceptible to
the harmful or lethal effects of fetotoxic or teratogenic
agents during the early stages of pregnancy, the occurrence
of these miscarriages within approximately two months of the use
of 2,4,5-T in the Alsea area suggested a possible relationship
between the use of the pesticide and the miscarriages
reported for this group of women. For these reasons, the
Agency began an epidemiological study to determine if the
occurrence of the spontaneous abortions in the entire Alsea
area (parts of three counties comprising 1,600 square miles)
bore any relation to the use of 2,4,5-T in the area. To
answer this question, the Agency gathered information and
data from hospitals on the occurrence of spontaneous
abortions in the Alsea Study area and compared these
data to comparable data from a rural area where there was
little or no known use of 2,4,5-T or other dioxin-contaminated
-38-
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phenoxy herbicides (Control area). Data on spontaneous
abortions from an Urban area near Alsea were also reviewed
for the study.
The Agency's preliminary analysis of the data generated
through this study indicates that:
(1) The spontaneous abortion index— (hospitalized
miscarriages per 1,000 births) for the Alsea Study area
where 2,4,5-T was used was significantly greater than the
index for the Urban and Control areas where there was little
or no known use of 2,4,5-T;
(2) There was a dramatic increase in the spontaneous
abortion index for the Study area relative to the Urban and
Control areas in the months of June and July; this increase
followed, by approximately two months, a period in March and
April when 2,4,5-T was used to control vegetation in the
forested Study area; and
(3) Statistical analyses of these data indicated
that there was a significant correlation between the amounts
of 2,4,5-T used in the Study area during the spraying
season and the subsequent increase in the spontaneous
abortion index in the Study area.
^_l The investigators determined the spontaneous abortion
index by relating the number of hospitalized spontaneous
abortions to the number of live births, corresponding
to month of conception. The ratio derived in this way
is express as abort ions/1,000 births, related to month
of conception, and permits comaprison between areas of
different total population size. The index is based on
a five-month moving average for births to correspond with
monthly miscarriages for terms up to 20 weeks (about
five months).
-39-
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In conclusion, the Agency's systematic survey of
the occurrence of spontaneous abortions in an area of
2,4,5-T use indicates that there was an unusually high number
of spontaneous abortions in the area, and that the incidence
of spontaneous abortions may reasonably be related to the
use of 2,4,5-T in the area. The data further indicate that
the miscarriage experiences which the eight Alsea women
reported to the Agency were representative of the experiences
of the larger population of women living in the Study area.
The data and information which provide the basis for these
conclusions are summarized below.
(b) Results and Analysis
Comparison of the spontaneous abortion indices
for the Study, Urban, and Control areas for the period from
1972 through 1977 shows that women living in the Study area
where 2,4,5-T is used were more likely to experience
spontaneous abortions than women living in either the
Urban or Control areas (Table 1). The six-year spontaneous
abortion index averaged 80.8 for the Study area, compared to
averages of 43.8 and 65.4 for the Urban and Control areas,
respectively.
In addition to this general elevation in the Study
area spontaneous abortion index, there was a striking increase
in the Study area index for the months of June and July.
During June, the index in the Study area was 130.4, compared
to 44.9 and 46.0 in the Urban and Control areas, respectively.
-40-
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Table 1. Monthly Spontaneous Abortion Index for the Study,
Urban, and Control Areas (Oregon, 1972-1977)
—- • • • • • II • . •! r _ - _| _- - — .- - -.- ^_ \_ - __ „. -^rf- (,_,-— '- • T . • -- - __.!-•_, ._ J_
I Month
January
February
March
April
May
I June
i
1
1 July
August
September
October
November
December
[Average
Study Area
48.1
82.2
93.8
61.9
89.9
130.4
105.4
88.1
46.0
76.2
76.7
70.3
Urban Area
73.9
49.3
43.9
47.0
50.8
44.9
14.6
31.8
49.6
54.8
19.6
45.6
Control Area I Average I
1
82.0
28.1
48.1
97.5
63.2
46.0
55.3
79.8
85.3
50.5
54.3
94.5
1
68.0
53.2
61.9
68.8
68.0
73 .~8 f
I
1
58.4 |
r
66.6
60.3
60.5
50.2
70.1
80.8 I 43.8 1 65.4 | 63.3 I
1 1 1
-40a-
-------
For July, the indices were 105.4 for the Study area, compared
to 14.6 and 55.3 for the Urban and Control areas, respectively,
These data are presented graphically in Figure A.
The increased spontaneous abortion indices in the
Study area during June and July are particularly significant
when viewed in terms of data on the use of 2,4,5-T in the
*/
Study area.— Spraying records for the Alsea area for the
j^/ The preliminary report inadvertently included 3,530
pounds of silvex as 2,4,5-T in the estimates of usage in
the Study area. Conceptually, this flaw is not signifi-
cant: 1) since its effect would merely modify slightly
the very significant correlation coefficient between
herbicide use and miscarriages; 2) the nature of the
relationship between time of application and the mis-
carriages is expected to remain unchanged; and silvex
contains TCDD and could be expected to result in the same
effect.
Nonetheless, the Agency immediately had the analysis
rerun to determine whether specific change in numerical
estimates result.
Corrected 2,4,5-T use remained significantly correla-
ted with miscarriages occurring 2-3 months later (r=72;
p<«°O. Combined silvex and 2,4,5-T spray data were also
correlated with miscarriages since both compounds could
be hypothesized to cause the observed effect due to a com-
mon TCDD contaminant. This analysis also showed strong
correlation between use and miscarriages as would be
expected on the basis of animal studies (r=.69; p<.02).
The relative insensitivity of the correlation to
changes in quantity further demonstrates the inherent
strength of the relationship between the basic use pat-
tern and miscarriages occurring 2 to 3 months later.
-41-
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Figure A. Plot of Monthly Spontaneous Abortion Index for
the Study, Urban, and Control Areas
130 .
120
110 -
100 .
90
x
5 BO
c
H
c 70 J
o
1-1
t; eo
o
XI
« 50 .
40 -
30
20 .
10 -
• • Study Area
o -e> Urban Area
A A Control Area
c
m
Xi
0)
—r
M
~r~
c
CO
ffl
a
0)
u
o
0
2
U
0)
D
Month
-41a-
-------
study period indicate that 2,4,5-T use occurs primarily
between March 1 and April 30; substantially lower amounts of
the pesticide are used during May and still lower amounts
are used during July and August (Figure B). Examination of
this information on the use of 2,4,5-T in light of data on
the increased incidence of spontaneous abortions reveals
that this increase occurs approximately two months after the
period of annual application of 2,4,5-T in the Alsea area.
More refined analysis of these data on total abortions
and total 2,4,5-T use by month during the period from 1972
to 1977 indicates that there was a statistically significant
correlation between the abortion index in the Study area
and the amount of 2,4,5-T used there. That is, when the
increased spontaneous abortion index was compared to the
amount of 2,4,5-T used each month in the areas where the
women resided, the peak in the abortion index followed the
peak in the spray pattern by approximately two months. This
two-month lag time corresponds to the time predicted on the
basis of the initial reports from the eight Alsea women.
Because this correlation is statistically significant
(p<0.01), there is strong reason to suspect that the
spontaneous abortion increase was related to the use of
2,4,5-T.
In view of the laboratory data establishing that
2,4,5-T and its contaminant TCDD have embryolethal effects
in test animals and the susceptibility of the young embryo
-42-
-------
Figure B.
Pounds of 2 4,5-T Sprayed in Alsea Basin
Accumulated by Respective Month, 1972 through 1977,
Compared with Abortion Index for the Same Period
Pounds Sprayed
130 -
120
110 -
100 .
90
X
•S 80 _
c
H
c 70 .
o
t! 60 _
o
A
* 50 -
40 -
30
20
10
A
/ ^
/
/
/
/
y
\
\
\
\
V
A >•
t-i ti X a
A
•
/
/
/
,
,
/
/
\
\
\
\
\
•
\
\
\
\
>, C '-t
4 (0 S3
S '
\
\
\
\
\
• Aoortion index
X
f "*
^
•
\/
t
C7>
3
- 5
0
0
0
.H
- 4 x
c.
OJ
•H
T!
a)
cr>
" 3 5
i— i
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4J
U
rt.
_ o tj |
0
13
C
3
O
d.
- 1
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^ (-3 *c w o 20
Month
-42a-
-------
to fetotoxic and teratogenic agents, the increased spontaneous
abortion index in an area of 2f4,5-T use may reasonably be
interpreted to be a consequence of the exposure of women
residents of the area to the 2,4,5-T used for forest
*/
management.—
(2) Seveso (Italy) and Vietnam
(a) Seveso, Italy
On July 10, 1976, an accident at the ICMESA chemical
plant in the Seveso region of Italy released 2 to 10 pounds
of TCDD over a wide area. Hundreds of animals died, many
area residents reported skin disorders, and an area of
110 hectares was evacuated. The most pertinent reports on
this incident are provided by Reggiani (1977), Tuchman-Duplessis
(1977), and Whiteside (1977; 1978).
There is an apparent consensus that the reproductive
epidemiology of Seveso, as presented, does not provide
firm evidence of increased risk of spontaneous abortions or
congenital malformations following the explosion. The
Agency does not believe, however, that those investigations
V The Alsea experience may not be an isolated incident.
Reports of people adversely affected by exposure to phenoxy
herbicides and/or TCDD have frequently appeared in medical
and scientific journals. Recent summaries appear in IARC,
NRCC, and U.S. Air Force documents on phenoxy herbicides and
dioxins. Further, as a result of the 2,4,5-T RPAR, the
Agency recently received numerous accounts of human health
effects attributed to phenoxy herbicides and/or TCDD. These
have been summarized in a document included in the record.
The cumulative effect of these reported incidents suggests
that people who live and/or work in areas of 2,4,5-T use may
experience adverse health effects.
-43-
-------
provide sufficient evidence of the absence of increased
teratogenic risk in humans, either for dioxin in general or
among the women of Seveso in particular. There are three
reasons for this conclusion: (1) deficiencies in the
available data; (2) methodologic deficiencies in the treatment
and interpretation of the data which are available; and
(3) suggestive indications in the available data that there
may actually have been an increase in teratogenic risk in
the area after the incident.
Major points which illustrate deficiencies in the
available data include: reproductive data in the area
"either do not exist or are deliberately underreported"
(Reggiani 1977); baseline rates for spontaneous abortions
and congenital malformations in the area prior to the
incident are not available; less than complete cooperation
was obtained from local physcians and less than complete
registration of pregnant women was attained (623 pregnant
women were registered, but 2,513 deliveries were recorded in
the area for July 1976 to May 1977; registration was thus
about 25%); while 34 women obtained therapeutic abortions in
the area, it is estimated that more than 2 times that number
obtained them legally or illegally elsewhere (Whiteside
estimates the number to be 4 times as many); and the
conventional pitfalls of reproductive epidemiology could not
be avoided (e.g., dependence on hospitalized spontaneous
abortions for numerators and hospitalized births for
-44-
-------
denominators, and different gestational cohorts for spontaneous
abortions and births occurring in the same calendar period).
Major points which illustrate methodologic deficiencies
in the treatment and interpretation of the available data
include: estimates of the total amount of dioxin released
ranged from 650 g (Reggiani 1977) to 11 kg (Whiteside), to
130 kg (Nature 11/28/76); estimates of exposure per person
2 2
varied from 29 ug/m (Tuchman-Duplessis) to 5,620 ug/m
(Reggiani 1977); exposure was characterized by geographic
zones, but reproductive data were gathered by geographic
districts raising questions whether the zones were contiguous
with the districts; spontaneous abortion rates were grouped
in 6-month intervals, but congenital malformation rates for
1976 were grouped in 12-month intervals which could have
masked an effect expected to be relatively acute or with a
2-3 month lag period; and the rates listed as "totals" for
the two groups of districts in Table 13 (in Reggiani 1977)
appear to be averages of the district rates and as such are
invalid and cannot be interpreted; the lack of chromosomal
abnormalities in the products of therapeutic abortions is
overemphasized since dioxin could conceivably produce a
teratogenic effect without producing a concomitant mutagenic
effect; and the wide interspecies variation seen in lethality
studies should not automatically be applied to teratogenic
effects because it is known that very low doses are teratogenic
in the rat (e.g., 0.01 ug/kg) and dioxin doses which caused
-45-
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teratogenic effects in rhesus monkeys were apparently as low
as 2.5, 50, and 500 nanogr atns/kg.
Suggestive indications of a possible teratogenic
effect in humans, from the available data, include: the
congenital malformation rate increased by 570% (about
7-fold) between 1976 and the first five months of 1977
(Table 14, 0.13 to 0.87 per 100 live births) (in Reggiani
1977). The birth rate dropped "sharply" following the
explosion (Whiteside) and cows aborted and produced malformed
offspring following the explosion. This lowered fertility
could be evidence of increased teratogenic risk; a local
doctor noted a "marked increase" in convulsions among
infants. (convulsions could be delayed effects of neuro-
toxicity in utero).
(b) Vietnam
A large amount of TCDD-contaminated herbicides
were used in Vietnam during 1962-1971. Possible health
effects have been reported upon retrospectively by groups
entering Vietnam. Tung et al. charged that 2,4,5-T was
responsible for much of the Down's Syndrome seen in [South]
Vietnam. Crummer was quoted by Honoroff as having observed
high incidences of children with Down's Syndrome. Tung et
al. also noted a very significant increase in the Hanoi
hospitals in hepatic carcinomas in the period 1962-1968
[1790/7911 cancer cases (10%), compared to 159/5492 (2.9%)
for the period 1955-1961].
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It should be remembered that most of the accidents
reported here were retrospective accounts. In the cases
of Seveso and Vietnam, reporting was (and still is) at
best piecemeal. The exposed populations contained numbers
of highly mobile persons who could not be accounted for
adequately.
(3) Exposure Analysis
(a) General Considerations
There are two components to any pesticide-related
risk: (1) the toxicological properties of a chemical,
and (2) exposure to the chemical. The risk assessment is a
summation of the conclusions in each of these areas. A
highly toxic chemical may pose high risk even if exposure
is low; conversely, a compound of low to moderate toxicity
may pose high risks if exposure is high.
Estimating probable exposure is difficult for a
number of reasons. While it would be inappropriate to
attempt a definitive discussion of these problems here, it
is useful to note a few examples. First, empirical data on
exposure is less available than is toxicology data. Second,
there are a number of exposure pathways which require
consideration (e.g., inhalation, dermal absorption, ingestion
of food residues, and ingestion of water residues).
Third, the inherent complexities of the dynamics of a
chemical's movement through the environment create formidable
obstacles to describing any given exposure pathway. For
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example, the chemical may behave differently in various
media depending upon a number of environmental factors which
can vary at any one application site. Thus, even when some
empirical data on a given route of exposure is available,
there are often uncertainties concerning the applicability
of the data to situations involving conditions which vary
from those which obtained at the study site.
The inherent difficulties of exposure assessment
always create a troublesome problem for decision makers.
These problems are of great concern in situations involving
chemicals which appear to pose risks even at very low levels
of exposure. As discussed above, the TCDD contaminant in
2,4,5-T and silvex is clearly such a chemical. For example,
TCDD is carcinogenic in rats at doses as low as 1 ppb and
fetotoxic in mice at doses as low as 0.01 mg/kg/day.
Moreover, the complexities of exposure assessment
are also amplified in situations involving persistent
chemicals. This is because the length of time a chemical
persists in the environment can increase the opportunities
for movement of the chemical and confound attempts to
eliminate pathways as pathways of concern. Time increases
the possibilities of variation in environmental factors
affecting chemical mobility.
The environmental persistence of 2,4,5-T and silvex
is relatively short due to physical, chemical, and biological
degradation processes. On the other hand, the contaminant
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TCDD has a much longer persistence in soil and is known to
bioaccumulate in fish (Matsumura and Benezet, 1973; Kearney
et al., 1973).
Generally, exposure assessments involve attempts at
modeling the likely exposure potential through several
pathways which are identified as pathways of principal
concern. The exposure assessment typically will involve
attempts to describe the movement of the chemical from the
site of application to persons potentially at risk, using
such empirical data as are available on the presence of the
chemical at various intermediate points in the critical
path. Conservative assumptions based upon such things as
knowledge about the behavior of similar chemicals, typical
environmental conditions affecting the use site, and
the like, are used to bridge inevitable gaps in the empirical
data. The objective, however, is a simple one: to obtain a
qualitative and (if possible) quantitative description of
the likelihood that a given chemical will move from where
it is applied to a given group of potentially exposed
individuals.
Since 2,4,5-T first surfaced as a subject of regula-
tory concern, determining potential exposure has been
the critical issue on the risk side of the regulatory
equation. Uncertainties about exposure resulted in suspension
of regulatory action in 1974, and the launching of an
ambitious project to generate exposure data (the "Dioxin
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Implementation Plan" or "DIP"). Primarily because of great
difficulties encountered in developing analytical methodologiei
with sufficient sensitivity to measure the extremely low
levels of TCDD which are of biological concern, the progress
of the DIP has been disappointing. To date, it has yielded
only fragmentary information.
In my judgment, the information which has recently
come to my attention as a result of the Alsea study consti-
tutes a dramatic and troubling new point of departure
for analysis of TCDD exposure concerns. As indicated above,
these data show a striking relationship between 2,4,5-T use
and increased incidences of spontaneous abortions among
women residing in the use area. As further developed above,
this effect is an effect which one would have predicted as a
likely outcome of human exposure, based upon a body of
animal data of almost unprecedented conelusiveness. The
Alsea study, to be sure, contained no data showing actual
exposure. However, concern for the health of humans who
may be exposed to TCDD, and therefore to 2,4,5-T or silvex
contaminated with TCDD, is heightened because scientists have
not demonstrated that there is a level of exposure that has
no adverse effects in humans.— Thus, in the face of the
highly significant relationship which the study showed, and
jj[/ A committe of the National Research Council of Canada
recently agreed with the authors of the World Health Organiza-
tion's monograph on TCDD that "for TCDD a no-effect level
for man could not be established" (NRCC 1978).
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the animal data, I conclude it is reasonable and in the
public interest to assume that the women in Alsea study were
*#/
exposed to TCDD.
Moreover, I also conclude that it is prudent to
assume that individuals who frequent or live in areas where
2,4,5-T or silvex are used may be exposed to TCDD in ways
and under conditions which may cause these individuals to be
exposed in ways qualitatively similar to those experienced
by the Study area women.
As developed below, I find that silvex use patterns
likely to cause exposure opportunities similar to the
exposure experienced by the Study area women are the forestry,
rights-of-way, pasture, home and garden, commercial/ornamental
turf, and aquatic weed control/ditch bank uses of silvex.
The Agency has identified pesticide applicators and persons
involved in pesticide application support activities, and
persons living in or frequenting areas of silvex use as the
principal groups of individuals who may be exposed as a
result of these uses of silvex.
**/ I have found it prudent to suspend because data from
the Alsea Epidemiological Study indicates that women experi-
encing adverse reproductive effects may have been exposed to
2,4,5-T. Information of this kind concerning a chemical's
effects on human populations is rarely available. Before
the Alsea Study was completed, Agency scientists developed
preliminary exposure analyses for 2,4,5-T based on use
information, assumptions, and modeling. Since I have
information of adverse human effects correlating with the
use of 2,4,5-T, I have chosen to rely on this correlation as
a basis for regulatory action, rather than on exposure
analyses based exclusively on use information and modeling.
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(b) The Alsea Study Area
(i) Description of Area
The Alsea Study Area comprises approximately
1,600 square miles of Oregon's forested Coastal Range centered
around the "Alsea basin," an area of approximately 400
square miles. It is bounded on the west by approximately
70 miles of the Pacific Coast and extends inland for distances
ranging from 10 to 35 miles. The Study area includes all but
the northern and southern reaches of the Suislaw National
Forest. Numerous commercially owned and Bureau of Land
Management forested acreages are interspersed throughout
this region. Mountain elevations of approximately 1,000 feet
are not uncommon; peak elevation is slightly more than 4,000
feet. The principal rivers are the Siletz, Alsa, Yaquina
and the Suislaw. Eastern fringes of the area drain eastward
into the Willamette Valley. Maximum runoff is reached
generally during the winter months as the result of storms
off the Pacific occurring usually as rain.
The Study area is predominantly rural. The four
largest towns have a total population of 14,450. All
other towns/villages have populations of less than 1,700.
Alsea has a population of 400 (1970 census). In addition,
many residences are scattered througout the forest areas.
All of the nine women who were idenitified in the first
phase of the investigation resided, at the time of pregnancy,
in rural residences located within 12 miles of Alsea.
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(ii) Use Pattern
2,4,5-T is applied to the forests in the Alsea
area almost exclusively by helicopter for control of undesir-
able vegetation such as red alder, vine maple, salmonberry,
and thimbleberry. In general, the compound is used in the
spring (March, April, or May) with a second application
made, if needed, in middle to late summer (July and/or
August). Over the six-year study period, 10,000 pounds of
2,4,5-T was distributed over a total area of approximately
7,000 acres. The usual practice was to treat any particular
site approximately once every five years. However, contiguous
stands could be treated in succeeding years. The spray
program spans only a few days' time, with the duration
depending on the number of acres to be treated and the
weather conditions.
To avoid contamination of water sources prior to
1978, the general application policy was to avoid spraying
near homes and to provide for a single swath of 30 to
60 feet on each side of any major stream. In September
1978, the Oregon Forest Practices Act created guidelines
which prohibited spraying within 500 feet of an inhabited
residence or within 200 feet on either side of streams with
fish and/or ones that are used for domestic water supplies.
However, drift and runoff could contaminate surface waters.
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(iii) Population Exposed to the Herbicide
Population of the Alsea Region is clustered in
several small towns; there are also isolated homes and
farmsteads in the forest area. Other groups which may be
traversing the forests of the Alsea Region include workers
engaged in forest management, incidental travelers, hikers,
students, surveyors, and delivery persons.
(iv) Modes of Exposure
The major method of dispensing 2,4,5-T in the
Alsea Forest Region is by helicopters. Although the
Oregon Forest Practices Act prohibits spraying near homes
or streams, there appears a likelihood that residents and
travelers of the Alsea Region might be directly exposed to
2,4,5-T during periods of application as a result of drift.
Drift from a helicopter flying over a forest canopy can
produce drift of the herbicidal spray at significant
distances from the path of the aircraft. Residents or
travelers in the path of the spray might be doused with the
pesticide spray.
Exposure to the population from drift and direct
contact is by the dermal (exposed skin) and inhalation
routes. Resident populations may also incur exposure to
2,4,5-T and TCDD subsequent to application. Waterborne
residues are a possible route of exposure; other possible
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exposure routes include fish, wildlife, and other foods
produced or found in the area. The fact that TCDD is
somewhat persistent and bioaccumulat ive may enhance exposure
possibilities. Furthermore, pesticide mixers, loaders,
applicators, and other workers may be exposed to the pesticide.
( c) Comparison Between Presumed Exposure in The
Al sea Study Area and Possible Exposure in
U s eS
The Alsea Study shows a significant correlation
between the use of 2,4,5-T in the Alsea area and increased
incidence of spontaneous abortions within approximately two
months after application. The Agency believes that it is
prudent to assume that the women studied were exposed to
2,4,5-T. While the Agency cannot determine the actual
routes of exposure, information about how 2,4,5-T is applied,
population densities, and proximity of Study area residents
to spray areas provides a basis for making assumptions about
possible chances for exposure.
That 2,4,5-T was applied by helicopter rather than by
ground application methods in Alsea, enhanced the potential
for exposure to 2,4,5-T from drift. Aerial application is a
principal method for applying 2,4,5-T and silvex. Most of
the phenoxy herbicides applied in forests and on rights-of-
way are applied aerially. In contrast, in pastures, applica-
tion of 2,4,5-T and silvex usually is by spot treatment with
knapsack spraying equipment. This method, causing less spray
distribution than aerial application, lessens potential
exposure from drift.
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Alsea inhabitants live in towns and residences
scattered throughout forests in which 2,4,5-T was applied.
Effects occurred even though application near residences
and streams was prohibited. The Study area women who
experienced spontaneous abortions were residents of the
area. Their exposure to 2,4,5-T or TCDD may have occurred
either while they were at home or while they were in nearby
forest areas. Bystanders, workers engaged in forest management,
people visiting the forests for recreational purposes, and
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others would have exposure potential similar to the exposure
potential of the Study area women away from their homes.
Because TCDD persists in the environment, such non-residents
may have been exposed to 2,4,5-T and TCDD during or for some
unknown length of time after application had occurred.
The Study area women may have been exposed to
2,4,5-T or TCDD through ingestion of drinking water, fish,
and wildlife. Residents are more likely to be exposed
through this route than infrequent visitors to the spray
area. Frequent visitors or workers in the area would have
exposure potential similar to that of residents. All other
forest areas in which 2,4,5-T or silvex is used are most
*/
obviously similar to the Study area.—
The use of silvex to maintain rights-of-way involves
exposure potential similar to the exposure potential
of the Study area women: residents of the application area
and workers and visitors who frequent the area may be
exposed.
The Agency estimates that a considerable number of
people may be exposed to silvex and TCDD as a result of the
use of silvex in non-urban areas to maintain rights-of-way.
Rights-of-way uses include highways, railway lines, electric
power lines, and pipelines. A principal method of applying
~*1Commercialforests are defined as those lands not
withdrawn for non-timber purposes which are capable of
growing 20 cubic feet of wood per year of desirable species.
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silvex is by aircraft, which was the method of application
in the Alsea, Oregon area.
The population that is most likely to be exposed are
people who live in the path of the spray or in the area of
drift.— A large potential exposure group would be
comprised of people living along railroad tracks and along
highways. Other groups that may be exposed are those that
live in forests or plains along power lines and pipelines.
The residents may be exposed to TCDD through the diet for
longer periods of time due to low levels of TCDD contam-
ination in water and food. An additional potentially
exposed group are people working in, or traveling through,
the treated area.
Exposure from the use of silvex in pastures is
** /
likely to be lower than the Study area.—7 Pastures
V Factors which affect drift include wind direction and
velocity, turbulence, relative humidity and air temperature,
atmospheric stability, pesticide formulation, application
equipment, and spray volume. For purposes of this analysis,
the Agency conservatively estimated possible pesticide drift
at 1/2 mile. The Agency notes, however, that pesticides
could drift farther depending on the variables listed above.
Some pesticide drift has been reported as far as 22 miles
from target (EPA DRAFT: "Report to Congress/Study - ULV," p.
95). In addition, this same draft report estimates that
percent of pesticide drift over 1,000 feet from the target
variously ranges from a low of 10% to a high of 90%.
**/ Pasture is defined as land producing forage for animal
consumption, harvested by grazing, which has annual or more
frequent cultivation, seeding, fertilization, irrigation,
pesticide application, and other similar practices applied to
it. Fencerows enclosing pastures are included as part of
the pasture.
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are likely to be near farmhouses and small towns. The
populations which may be exposed to silvex include farm
families, other rural residents, and workers in rural
occupations. The predominant method of application for
controlling brush in pastures is spot treatment with knapsack
spraying equipment. The distribution of silvex from this
technique is lower than thai, from forestry and right s-o f-way
use, because this technique produces only short-range drift.
Indirect exposure due to residues in food is possible.
Generally, persons involved in applying pesticides
have greater exposure to the chemicals than do residents of
the area in which the pesticides are used. There is no
reason to believe that this would not be true of silvex.
Therefore, the Agency is concerned about potential exposure
to pilots, ground spray crews, mixers and loaders, and
flaggers, all of whom are exposed to silvex in the applica-
*/
tion process .—
For aerial application, the ground crew, including
mixers and loaders of the aircraft, is the group with the
highest potential for exposure by both dermal and inhalation
T]In response to the 2,4,5-T RPAR, the American Paper
Ynstitute and the National Forest Products Association
recently submitted a detailed study of applicator ex-
posure to 2,4,5-T during both aerial and ground appli-
cations (2,4,5-T RPAR submission #1023H - 30000/26).
The results of this study indicate that workers who handled
the pesticide concentrate had the highest exposure, followed
by knapsack sprayer applicators, mist blower drivers,
helicopter pilots, supervisors, and flagmen.
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routes, because they handle the concentrated formulations.
The flaggers on the ground are exposed mainly by drift of
the diluted spray deposited on their exposed skin, and to a
lesser degree by inhalation. The pilots are expected to be
exposed to smaller amounts of silvex by dermal and inhalation
routes because they sit in the enclosed cabin of the helicopter
while applying the diluted herbicide spray. For the ground
application techniques, the applicators and mixers are the
workers running exposure risk. Inhalation exposure may be
more significant when fine mist sprayers (for example,
foliar treatment are used) in contrast to stump treatment
spraying with a coarse spray. The reason for this is that
smaller spray droplets are more readily absorbed through the
lungs.
The exposure to silvex of persons using the pesti-
cide for home and garden use may be higher than the ex-
posure of most other groups potentially exposed. The
exposure from home and garden use would appear to be
greater than the exposure from forestry use in areas
such as Alsea. Furthermore, home and garden exposure
to owners/applicators may be greater than the exposure
of persons involved in commercial application of silvex
or 2,4,5-T since home users are not likely to wear
appropriate protective clothing or to take adequate
precautionary measures.
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Several home and garden application techniques
have inherent exposure potential. Hose-end diluters
probably have a high potential for dermal exposure to
both applicators and bystanders because of the long range of
the spray arising from these devices. The coarseness of the
spray, however, probably precludes any significant inhalation
exposure or drift away from the site of treatment.
Another possibility for exposure from home and
garden use occurs during the dilution of liquid concentrates
of silvex. The concentrate may spill or splash onto the
exposed skin of the user. Additional exposure to householders
may occur during spraying, mixing, and cleanup of equipment.
It is unfortunately true that householders may not exercise
appropriate caution, and may, for example, spray upwind,
thus receiving an unduly high amount of drift on face,
hands, and other unprotected parts of the body. Other
sources of potential applicator exposure include splashing
and low-distance drift droplets from tank sprayers, aerosol
containers, and dust particle drift from granular application.
Persons who are bystanders could also receive exposure
to silvex by accidental splashing or drift, or low-level
drift droplets and/or dust particles from granular formulations,
Some home and garden applications of silvex are
made by lawn care professionals, who work much more extensively
with this herbicide than would a single homeowner. These
professionals, however, are likely to exercise more care
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during the use of pesticide chemicals, and thus avoid
spills or substantial dermal exposure.
Silvex is also used for weed control in sites such
as public parks, golf courses, athletic fields, institutional
lawns, and sod farms. These uses are similar to the home
and garden uses described above. The most exposed group is
likely to be the applicators. Another group of persons
who may be exposed are bystanders, sports enthusiasts,
residents of the institutions, etc. The routes of exposure
for all these groups are likely to be chiefly dermal. The
applicators are exposed not only by applying the herbicide,
but also by mixing and diluting the concentrate. Bystanders
and people who enter treated areas will incur less exposure
than applicators, unless they get aceidentially splashed or
sprayed.
Silvex is used to control plants in waters used for
recreation and in farm ponds. Thus, the general population
may be exposed from this use of silvex by swimming, engaging
in water skiing, drinking treated waters, or eating fish
caught in waters where silvex has been applied.
The applicators involved in this use of silvex
are professional or staff persons engaged by authorities
responsible for maintaining clean waterways. Applicators
apply the material from boats. Applicator exposure is
likely to be greater if the applicator uses a mechanical
sprayer than if the applicator pours the formulation
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directly onto the water, unless spillage results acci-
dentally from pouring. The fine mist dispensed by the
mechanical sprayer could be deposited on unprotected skin or
could be inhaled.
C. Determination of Benefits
The Agency has evaluated the economic effects of
suspension of non-crop uses of silvex for a period of two
years until completion of the decision whether these uses
*/
should be cancelled— . The co nsideration of economic
impacts stemming from a suspension is limited to a two-year
period because the maximum projected length of a cancellatin
proceeding would be tgwo years. A suspension order remains
in effect only during a cancellation proceeding. Thus, only
the impacts which would arise during this period would be at
issue in a suspension. Any impacts which would be caused by
a suspension, but which would be felt after this period, are
**/
also considered— .
^_l The emergency suspension order will take effect immediately
upon issuance of this Notice and remain in effect during
any subsequent emergency suspension hearings. At the
conclusion of the hearings, a decision will be made whether
to continue or remove the suspension order during the
ensuing cancellation proceedings. Economic impacts are
therefore separately evaluated for the 3 1/2 month period
allocated for an emergency suspension proceeding as well as
for the two years which may be required for a cancellation
proceeding.
**/ The Agency's analysis is based on information from a
"rTumber of sources including RPAR rebuttal comments received
by the Agency from registrants, users and other parties
during the RPAR process; and the USDA-States-EPA 2,4,5-T
RPAR Assessment Report (February 15, 1979) as well as other
relevant data. Although the 2,4,5-T Report attributes a
role to EPA, the final report has neither been completely
reviewed nor approved by EPA. Therefore, although the
Agency has relied on some portions of the report, it
cannot and does not wish to adopt all portions of the report
as reflecting the Agency position on matters discussed
herein.
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The non-crop uses of silvex include those it has in
common with major uses of 2,4,5-T (forestry, pasture, and
rights-of-way), as well as home and garden, and commercial/
ornamental turf and aquatic weed contro1/ditch bank.
(Rangeland is not included). In addition, the Agency
has evaluated the economic effects of emergency suspension
of these uses - i.e., the consequences of silvex not being
available for these uses for the duration of an emergency
suspension (3 1/2 months).
Domestic usage of silvex is estimated to be about 2.8
to 3.3 million pounds. Commercial/ ornamental turf and home
and garden uses of silvex are the largest volume uses,
comprising more than 50% of domestic usage. Aquatic weed
control/ditch bank usage accounts for about 8% of annual
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usage. Other uses, primarily pasture, account for about 10%
of use. The proposed suspended uses of silvex account for
about two-thirds of its annual usage. The major remaining
uses are rangeland, rice, and sugarcane.
Economic impacts of suspending forestry, pasture,
rights-of-way, and non-crop usage of silvex during a two-year
period, generally were estimated by assuming all registered
alternatives are available, except 2,4,5-T which is also
subject to suspension. The analysis generally provides
qualitative estimates of impacts since data are not available
to support precise quantitative estimates.
Economic impacts during a suspension would depend
upon the treatment options actually selected by users. For
many, use of silvex during 1979 and 1980 would be optional
(i.e., could be delayed to a later year). Other users might
choose to use alternatives immediately.
The Agency's analysis indicates that a two-year
suspension of silvex non-crop uses would not significantly
affect U.S. production or prices of any commodities or
services in affected sectors. Economic impacts of the
suspension would be minor in most cases, even at the local/
regional level.
The major economic significance of suspending silvex
is that it would not be available for more extensive use on
forest and pasture sites as a 2,4,5-T substitute. Silvex
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usage on those sites could increase significantly in the
event of suspension of 2,4,5-T on those sites because silvex
is an economic alternative for 2,4,5-T in many instances.
Economic impacts during the 3 1/2 month emergency
suspension proceeding would be negligible. Any silvex
treatments scheduled for this period could be delayed
without affecting the efficacy of the treatments or cost to
users .
The economic impacts of suspending each individual
non-crop use of silvex, including those it has in common
with 2,4,5-T, are discussed below.
(1) Forestry
Silvex now appear to be used on a rather limited
scale in forestry. Bureaus of the U.S. Department of Interior
(USDI) and the U.S. Forest Service (USFS) have used silvex
in the past year. A USDI policy memorandum (June 12, 1970)
prohibited use of 2,4,5-T and restricted the use of picloram,
but did not include silvex on either prohibited or restricted
lists. Nonetheless, USDI use of silvex appears to have been
discontinued during 1977. However, as much as 30,000 acres
(up to 50,000 pounds a.e.) were treated annually by BLM
during the early to mid-1970's. Forest Service use has
declined and currently involves very small quantities (less
than 500 pounds a.e.) Some silvex could be used by non-
govermental users, but no documentation of such usage is
available.
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Silvex can be used at either or both of two stages in
the production— of conifers: (1) preparing sites for
reforestation and (2) releasing young trees from hardwood
competition. Each operation is undertaken once in the 50
jj[_/ Silvex is sometimes used for other forestry herbicide
operations, including rehabilitation or species conversion,
fuel break maintenance, and timber stand improvement. The
major forestry uses of silvex are site preparation and
release, which are the focus of this analysis.
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year cycle of a softwood stand. Silvex, as well as other
chemical and non-chemical control methods, may be used
individually or in combination for site preparation and
release.
Use of silvex for site preparation is not critical
although it is cost effective. Several other chemicals, as
well as non-chemical methods, are also effective for site
preparation. Picloram and 2,4-D, sometimes combined, are
the most effective substitute chemicals. 2,4-D costs less
than silvex but controls a more limited spectrum of weeds
and often has to be used more frequently, thus resulting in
higher costs than a single silvex treatment. In the past,
2,4,5-T has been preferred to silvex for site preparation
because it controls a wider variety of hardwoods.
Because the release (weeding) operation is conducted
after the seedling trees are in place, a selective herbicide
which will not harm the seedlings is preferred. This is
particularly true for pine; silvex provides control of many
hardwood competitors; however it also can damage pine
seedlings. As a consequence of its lack of selectivity
silvex has not been extensively used for release treatments.
Its use has been limited to non-pine conifer stands in the
west and fir-spruce stands in the Northeast.
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In both agencies, costs have already been increased
by $20-$200/acre due to the use of release methods other
than silvex and 2,4,5-T. Site preparation continues at cost
increases of $10-$40/acre using picloram/2,4-D and other
chemicals on those areas which require herbicide controls.
Release costs in Washington and Oregon are $20-$50/acre for
substitute chemical control. Manual control, when used,
increases costs about $60-$1OO/acre more than silvex.
USDI is presently reviewing the department policy
regarding pesticide use and is considering adding silvex to
the list of prohibited chemicals. USDI decisions regarding
1979 plans for use of silvex are pending EPA decisions, and
alternative plans have been developed for vegetation management
wi thout silvex.
The suspension of forestry uses of silvex for either
3 1/2 months or two years would not have any significant
current economic impact because the chemical is not now in
use. The prinicipal potential users, USDI and USFS, have
already discontinued use. The only significance of the
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silvex suspension for forestry use is that it would not be
available as a substitute for 2,4,5-T.
(3) Rights-of-Way
Silvex is used to control woody and herbaceous
plants on vegetated rights-of-way (railroad, highway,
electric transmission, and pipeline) which could hamper
the use of the system (weeds encroaching on highways)
threaten the system's equipment, and/or interfere with
inspection and maintenance of the system.
Manual and mechanical methods are the most common
control practices on rights-of-way acreage. Combining
chemical and non-chemical control methods is common as is
use of herbicide combinations to enhance their effectiveness
and expand the spectrum of plants to be controlled in a
single application.
Chemical treatment uses a variety of chemicals,
including phenoxy herbicides. Usage of silvex for rights-of-
way vegetation control is minimal, e.g., less than 2% of
rights-of-way firms use it.
If silvex is not available, users can be expected to
treat with other herbicides. Dichlorprop, 2,4-D, and
picloram mixed with 2,4-D are all cheaper than silvex.
Several alternatives control more species than silvex, and
equivalent control may be achievable at less cost. No
significant negative economic impacts could be expected from
a two-year suspension of this use. Economic impacts during
a 3 1/2 month emergency suspension would also be insignificant,
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(3) Pasture
The phenoxy herbicides (2,4-Df 2,4,5-T and silvex)
are registered for the control of many woody and herbaceous
weeds on pasture. Silvex is generally more effective
for woody plant control than 2,4-D but controls a
narrower spectrum of weeds than 2,4,5-T.
Current silvex usage on range and pasture is apparently
small enough that no reliable estimates of use have become
available. No more than 500,000 pounds active ingredient are
used annually. Most of this amount is probably used on
range, although states such as Minnesota, Virginia, and New
England states recommend silvex for control of some weeds in
pasture. In Massachusetts, about 9,000 pasture acres are
treated with silvex annually, but pasture usage in other
states has not been reported. Silvex was not considered by
the 2,4,5-T Assessment Team to be an alternative to 2,4,5-T
for pasture or fencerow applications because of its relatively
narrow spectrum of control.
Brush control with herbicides on pasture and along
pasture fencerows is usually accomplished by spot treatment.
Presumably, silvex is also applied in this manner when it is
used.
Since other chemicals, e.g., picloram, dicamba,
2,4-D, are generally preferred to silvex for pasture use,
farmers who currently use silvex would presumably adopt
these alternative herbicides.
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No yield or production effects would occur during a
two year suspension. For individual farmers using silvex,
alternative controls might be more expensive. If so, these
farmers' income will be reduced by the amount of the cost-of-
control increase. Such effects will be nominal in most
cases. There would be no impacts on consumer prices or the
general economy. Agricultural income may be reduced by an
immeasurably small amount. In view of the limited economic
impacts from a two year suspension period, economic impacts
during the 3 1/2 months required for an emergency suspension
proceeding would be of no significance.
(4) Commercial/Ornamental Turf
Ornamental turf includes golf courses, athletic
fields, parks, playgrounds, highway turf, and turf farms for
purposes of this analysis. Of these, golf courses are the
major consumer of herbicides used to control broadleaf turf
weeds.
Precise current estimates of silvex use on turf are
not available but annual usage could be as high as 2 million
pounds active ingredient. Combinations of 2,4-D, MCPP, and
dicamba are readily available and effective treatments for
clover and chickweed which are major broadleaf weed pests.
In golf courses, these chemicals are common control treatments
for these pests. Data on other turf uses are not available.
Without silvex, users will shift to combinations
of 2,4-D, MCPP, and dicamba to control broadleaf weed
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pests. Treatment costs with silvex, silvex combinations,
alternatives, and combinations of alternatives vary depend-
ing on region, target weed species, application rates,
formulations, and package size. Material costs for silvex
and dicaraba are comparable at $7.50 per acre. Silvex
combined with 2,4-D is about $1 per acre more expensive than
MCPP, MCPP + 2,4-D, and 2,4-D + dicamba. Combinations of
MCPP/2,4-D/dicamba are about $4.50 to $14.50 per acre more
expensive than silvex/2,4-D mixtures. On the average,
alternatives are about $3.50 per acre more expensive than
silvex and silvex mixtures.
For individual turf managers, these control cost
increases will be nominal. Golf courses, for example,
spend $80-$90 per acre for turf maintenance which includes
chemical fertilizers, fungicides, herbicides, and insecti-
cides, but excludes irrigation, mowing, and other direct
costs. Thus, increased broadleaf weed control costs of
$3.50 per acre could increase maintenance costs by about 4
percent. Economic impacts during a two year suspension
would not be adverse to the overall commercial/ornamental
turf sector.No economic impacts are anticipated during the 3
1/2 month emergency suspension proceeding. Most treatments
scheduled during this period could be delayed without
causing significant control problems or increasing user
costs.
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(5) Home and Garden
Most of the herbicides used by the homeowner in the
U.S. are for control of broadleaf weeds and grass pests in
lawns. At least three-fourths of U.S. homeowners do not use
any herbicides. Liquids are more popular than granular
forms in terms of quantities used and dollar sales. Several
hundred thousand pounds of silvex are used annually on home
lawns.
Silvex is most commonly used with 2,4-D, MCPP, and
dicamba to control species resistant to 2,4-D (i.e.,
chickweed, clover, spurge and henbit). Based on label
claims and state recommendations, combinations of 2,4-D,
MCPP, and dicamba would be equally effective.
Homeowners would shift to products containing 2,4-D,
MCPP, and dicamba in the event of a silvex suspension.
These alternatives are effective, readily available,
and comparably priced. Thus, homeowner adjustments for
either 3 1/2 months and/or 2 years suspension would be
nominal.
(6) Aquatic Weed Control/Ditch Bank
Aquatic weeds are a nuisance in water bodies used for
recreation and in farm ponds used for watering livestock.
Major users of herbicides for aquatic weed control are
government and private recreational organizations and
farmers. Government purchases of aquatic herbicides account
for nearly half of annual sales. Private recreation organiza-
tions account for more than a third and farmers the remainder.
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Silvex and a mixture of silvex and endothall are
registered for use in aquatic weed control in ponds, lakes,
marshes, and shorelines. Silvex controls submerged, emerged,
and floating types of flowering plants. Essentially all
weeds controlled by silvex are sensitive to various other
major aquatic herbicides, including 2,4-D, diquat, endothall,
and dichlobenil. Silvex, 2,4-D, and diquat exhibit similar
herbicidal activities in aquatic sites.
Silvex is also applied to drainage ditch banks and
canal levees. Particular target weeds include the phyrea-
tophytes, various exotics, and other woody plants such as
rubber and willow trees (Loeser, 1975; Baker, 1975).
There appear to be no viable alternative chemical controls
for some plant pests such as the phreatophytes and some
exotics (Loeser, 1975). However, there are many other
chemicals registered that are effective on many species
found along ditch banks and canal levees.
For most uses of silvex, 6 pounds a.i./acre per
foot are applied in late spring to early summer. Approximately
240,000 pounds of silvex were used in 1972 for water
management purposes (von Rumker et al. 1974). This estimate
includes silvex used in static water areas such as recrea-
tional sites, reservoirs, settling ponds, and ditch banks.
At an assumed application rate of 6 pounds of silvex per
acre, approximately 60 thousand acres of static water and
ditch banks were treated in 1972.
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Consumption of silvex for weed control in stationary
water areas is not critical due to the availability of
effective chemical alternatives including 2,4-D, diquat and
dichlobenil. Also, the Argentine flea beetle is an effective
biological control of alligator weed when used in an IPM
program with silvex or 2,4-D.
Economic effects of suspending aquatic/ditch bank
users of silvex for 3 1/2 months or 2 years would be nominal
because effective, economical alternatives are available.
There would not be a significant economic burden on users.
V. PROCEDURAL MATTERS
This order directs the emergency suspension of the
forestry, rights-of-way, pasture, home and garden, aquatic
weed control/ditch bank, and commercial/ornamental turf uses
of silvex. Registrants affected by emergency suspension
actions may request an expedited hearing before the Agency.
This section explains how to request an expedited hearing,
the consequences of requesting or not requesting an expedited
hearing, and the procedures which govern an expedited
hearing in the event one is requested.
A. Procedures for Requesting a Hearing
(1) Who May Request a Hearing and When the Request
Should Be Made
Registrants of silvex products registered for the
forestry, pasture, rights-of-way, home and garden, aquatic
weed control/ditch bank, or commercial/ornamental turf uses
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of silvex may request a hearing on these specific registered
uses of silvex within five days after receipt of this
opinion and order.
(2) How to Request a Hearing
Registrants who request a hearing must follow
the Agency's Rules of Practice Governing Hearings (40 CFR,
Part 164). These procedures specify, among other things:
(1) that all requests for a hearing must be accompanied by
objections that are specific for each use for which a
hearing is requested [40 CFR 164.121(a) and 164.123(b)] and
(2) that all requests must be filed with the Office of the
Hearing Clerk within the applicable five (5) days [40 CFR
164.l21(a)]. Failure to comply with these requirements will
automatically result in denial of the, request for a hearing.
Requests for hearings must be submitted to:
Hearing Clerk (A-110)
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
B. Consequences of Filing a Hearing Request
Under FIFRA Section 6(c)(3) the emergency suspension
order becomes effective immediately and, unless stayed,
continues in effect until completion of the expedited
hearing and issuance of a final order of suspension. The
statute provides that where an administrative hearing is
requested, the emergency order is subject to District Court
review on the emergency finding. The final suspension order
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issued by the Administrator after a hearing may keep the
suspension in effect, modify it, or terminate it. A final
suspension order issued following a hearing is then reviewable
in the Court of Appeals.
The statute provides that if a hearing is requested
on the Administrator's emergency suspension actions regarding
silvex before the end of the five-day notice period, the
hearing stage is to begin within five days after receipt
of the request, unless the registrant and the Agency agree
that it shall begin at a later time. No party, other than
the registrant and the Agency, is to participate, except
that any person adversely affected may file briefs within
the time allowed by the Agency's rule. Hearings on emergency
suspension, like hearings on ordinary suspension, are
subject to the provisions of subchapters II of Title
5 of the United States Code, except that the presiding
officer need not be a certified hearing examiner. The
presiding officer has ten days from the conclusion of the
presentation of evidence to submit recommendations to the
Administrator, who in turn has seven days to issue a
final order on the issue of suspension.
C. Consequences of Not Filing a Hearing Request
Under the statutory scheme, if there is no request
for a hearing on the Administrator's suspension actions
within the five-day notice period, the emergency suspension
order becomes a final suspension order, which remains in
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effect until the conclusion of the cancellation proceedings,
unless modified or vacated sooner (40 CFR 164.130). Court
review of an emergency suspension order, including the
special review before the District Court discussed in Part
II, is available only if an administrative hearing has been
requested within the applicable five-day period [FIFRA
Section 6(c)(2), 6(c)(3)].
D. Supplementary Procedures
EPA's Rules of Practice for expedited hearings are
set forth at 40 CFR Part 164, Subpart C. I do not know if a
hearing will be requested on these suspensions. If it is,
however, I am establishing the following procedures to
supplement the existing regulations in governing its
conduct.
1. A deadline is being established for the comple-
tion of all hearing procedures and the rendering of a
recommended decision under 40 CFR 164.121(j). That dead-
line is 90 calendar days from the first prehearing con-
ference, which shall be held in accordance with the time
requirements described below.
2. I am naming certain EPA employees to serve as a
hearing panel in any hearing arising out of this notice (see
Appendix A).
I am naming certain additional persons to be available
to provide technical advice and staff support to the hearing
panel (see also Appendix A). If questions arise at the
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hearing which persons in this category are uniquely qualified
to assess, they may be called on to serve on the panel
either in addition to, or in substitution for, the three
panel members named above.
The panel will conduct the hearing and submit a
recommended decision to me under 40 CFR Section 164.121(j).
None of the persons named above is subject in the normal
course of their duties to the supervision or direction
of any employee or agent of EPA who is a member of the
Agency trial staff named below. See 5 U.S.C. Section
554UH2).
Since 5 U.S.C. Section 554(d)(l) provides that
those presiding at adjudicatory hearings may not "con-
sult a person or party on a fact in issue [in the course
of preparing their decision] unless on notice and opportunity
for all parties to participate," neither myself nor my
appellate staff will consult with the panel or its supporting
staff on any matters involving this case from the date of
notice until a recommended decision is issued. Members of
my appellate staff are listed in Appendix A. We will
conduct an independent review of the questions presented on
appeal of any recommended decision. However, in doing this
we will feel free to consult with the hearing panel and the
support panel, since they will have conducted the initial
proceedings and brought expert knowledge to evaluating the
record.
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The following Agency bureaus or divisions, and
ther staffs, are designated to perform all investigative
and prosecutorial functions in this case: Office of
the Deputy Administrator— , Office of Toxic Substances,
the Office of General Counsel,
and the Office of Enforcement.
From the date of this notice until any final decision,
no member of the hearing panel, its support staff, my
appellate staff, or myself, shall have any esx_ parte contact
with any trial staff employees, or any other interested
person not employed by EPA, on any of the issues involved in
this proceeding. However, persons interested in this case
should feel free to contact any other EPA employee, including
both trial staff and persons not explicitly named as panel
members or assistants, with any questions they may have.
3. I am directing the hearing panel to proceed as
follows to streamline proceedings in this case:
a. My findings on imminent hazard and emergency
for suspended uses of silvex together with supporting
^_/ The Deputy Administrator may properly be included in
the trial staff since the prohibitions of 5 U.S.C. Section
554(d) do not apply to "the agency". Her inclusion is
necessary if guidance on general policy matters is to be
available to the trial staff and, to free a high agency
official to talk to outside interested persons about the
questions involved without the constrains otherwise imposed
by the ex parte provisions of the APA and the Government
in the Sunshine Act. The Deputy Administrator will take
no part in the detailed work of preparing and presenting
the Agency's case.
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information are in my opinion and order, which is available
for inspection in the Office of the Hearing Clerk. Additional
supporting information, including references cited in the
opinion and orders, is also available for inspection in
the Office of the Hearing Clerk. Together these documents
** /
constitute the Agency record in this matter.—EPA has
also attempted to put this information in perspective
through a narrative summary and analysis.
b. The scheduling of any hearing, particularly
in its earlier stages, involves a balancing between the
need to conduct an expeditious hearing and a concern
that the hearing not proceed too far before the identity
of those registrants requesting a hearing is established.
In arranging for the first prehearing conference, I have
attempted to accommodate both interests. The hearing
panel shall convene the first prehearing conference within
five days after receipt of the last request for a hearing
by a registrant or 15 days after the issuance of my
opinion and order, whichever comes earlier. The 15-day
maximum should ensure that all registrants wishing to
participate in the hearing have been given ample time
to file a hearing request after receiving notification
of my suspension actions.
**/ Some of the documents in the record may be entitled
to confidential treatment under FIFRA Section 10, as amended.
Parties to the hearing may have access to such documents,
if appropriate protective arrangements are made. See
also the footnote to this Order concerning confidentiality
of data in Section IV.A.(1)(a)(i).
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c. Within ten days from the first prehearing
conference, any person requesting a hearing shall submit
focused written comments on this opinion and order con-
sisting of a count erstatement of proposed findings on
the issue of imminent hazard presented by silvex together
with supporting information. A narrative summary explaining
its bearing on the case should also be included.
d. The Agency trial staff shall have seven
days thereafter to file supplemental information and
comment s.
e. Within five calendar days from the
filing of any supplemental information by the Agency
staff, the panel shall convene a second prehearing
conference. At this conference all parties shall
appear prepared to present arguments on the signfici-
ance and relevance of the material already presented.
This prehearing conference shall also hear all requests
for oral presentation of direct evidence and cross-
examination, and the reasons supporting them. At this
time each party shall present the names of witnesses
available for cross-examination on the matters the
party is putting into issue. The party may list
documents (or portions thereof) on which the potential
witness is available for cross-examination in lieu
of filing a formal witness statement.
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f. Within five days after the prehearing
conference is over, the panel shall issue a hearing order
setting the schedule for oral presentation of witnesses and
cross-examinat ion.
(1) Requests for oral presentation of direct
testimony shall be granted only if it is demonstrated that
the testimony can be presented meaningfully only in that
form; in all other cases, direct testimony shall be in
writ ing.
(2) Requests for cross-examination shall be
granted only if all of the following showings are made:
i. The request concerns factual matters. Cross-
examination will not be granted on matters of policy
or law.
ii. The factual matters are legitimately in
dispute in light of the record.
iii. The factual matters are material to the
decision to be made.
iv. Cross-examination is the most efficient
way of resolving the dispute over these factual matters (as
opposed to such alternatives as production of further
information, or informal conferences).
v. There is a reasonable expectation that cross-
examination will resolve the issue of material fact in a way
likely to influence the final decision.
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g. The testimonial phase of the hearing shall
begin three days after issuance of the order setting the
hearing schedule. At the hearing, the panel shall take an
active role in the development of the record through
questioning of witnesses and by issuing procedural orders
where necessary.
h. At the end of the initial testimonial
phase, the hearing panel may permit the introduction of
additional information designed to rebut the contentions
made by opposing parties.
i. The panel may revise any of the procedural
provisions of this notice other than the overall 90-day
deadline for rendering a recommended decision, the time for
which starts running after the first prehearing conference.
A discussion of some aspects of these procedures
follows:
(1) Deadlines
Deadlines for completing proceedings under FIFRA
have been twice endorsed by the National Academy of Sciences
[National Academy of Sciences, Decision Making in the
Environmental Protection Agency, Vol. II, p. 84 (1977);
National Academy of Sciences, Decision Making for Regulating
Chemicals in the Environment, p. 30 (1975)].
In addition, Congress has demonstrated a concern
for speedy action where suspensions based on a potential
threat to human health are concerned. It has required a
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hearing on such a suspension to begin five days after it is
*/
requested— , and has allowed ten and seven days respectively
for preparation of the initial and final decisions once the
hearing is over [FIFRA Section 6(c)(2)]. FIFRA was amended
in 1975 to require consultation by EPA with the Department
of Agriculture and a scientific advisory panel before taking
action in many cases; suspensions based on human health
grounds, however, were exempted from those requirements to
allow speedy action where speedy action was desirable
[121 Cong. Rec. H 9895-96 (daily ed. Oct. 9, 1975); 121
Cong. Rec. Section 19820-21 (daily ed. Nov. 12, 1975)].
Deadlines for completing the hearing have been
imposed in prior suspensions. See, e.g., In re: Vesicol
Chemical Co., et al.. 41 F.R.7552, 7553 (Feb. 19, 1976)
[Notice of Intent to Suspend Heptachlor and Chlordane], and
jn re: Dibromochloropropane, 42 FR 48915 (Sept. 26, 1977).
[Notice of intent to suspend and conditionally suspend
registrations of pesticide products]. The requirements set
forth in this order simply carry forward that practice.
(2) Use of a Panel
Despite the need for speedy action, the issues
involved in suspension are complex. Under the statute, a
*7Ido notregard the procedures set forth below as
inconsistent with this directive. What concerned Congress
was plainly that the hearing stage of Agency decision-
making begin promptly, not that the oral hearing itself
start unconditionally in less than a week. To interpret
the law otherwise would forbid the use of such accepted
aids to efficient decisions as prehearing conferences in
precisely the cases where efficiency is most required.
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judgement of "imminent hazard" must be based on considera-
tion of costs and risks of all types [FIFRA Sections 2(1),
2(bb)]. Given the necessary time constraints and the prelimi-
nary nature of suspension as a remedy, factual certainty may
be elusive. "[T]he function of the suspension decision
is to make a preliminary assessment of evidence, and probabi-
lities, not any ultimate resolution of difficult issues"
[Environmental Defense Fund, Inc. v. EPA, 510 F.2d. 1292,
1298 (D.C. Cir. 1975), quoting from Environmental Defense
Fund, Inc. v. EPA, 465 F.2d. 528, 537 (D.C. Cir. 1972)].
Arriving at even such a preliminary assessment
can present formidable difficulties. Considering risks,
questions can arise concerning the dispersion and persistance
of the pesticide in the environment and certain parts of
it, the conduct of animal feeding studies, the meaning
of those studies for human health, the validity of relevant
epidemiological studies, the reliability of using known
human exposure from one use pattern as a predictor of
potential human exposure in other use patterns, and finally
on what the upper and lower boundaries of any risks may
be and how firmly they are established. Considering benefits,
questions can be raised about the extent of use, the
availability, practicality, and effectiveness of substitutes
both now and in the future, and the range of the probable
economic impacts of a temporary ban on the pesticide, or
some use of it, in the light of all these factors.
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The job will be easier and better performed, if
I am allowed to rely directly on the talents of EPA employees
with expert knowledge of the technical fields involved
and with the professional ability to assess problems arising
in them. I believe it is for this reason that Congress has
provided that those presiding over suspension hearings need
*/
not be hearing examiners—'.
(3) Conduct of the Hearing
Overuse of cross-examination and courtroom formali-
ties, I believe, has made many FIFRA proceedings far longer
than was consistent with any rational purpose. The overwhelm-
ing bulk of legal analyses by those who have studied the
problem, and EPA's own experience demonstrate that scientific
and economic issues can be clarified by the exchange of
written material far more efficiently than through courtroom
hearings. I am directing that written submissions be used
here to focus the issues in an attempt to implement those
lessons. At the same time, particularly where Congress has
explicitly called for formal hearings, the accompanying
rights to reasonable cros.s-examination and oral presentation
must be preserved.
^J The fact that more than one person will preside is
of no legal significance. Even when 5 U.S.C. Section
556 requires a hearing to be presided over by an examiner
(or a person representing the Agency), it also specifies
that "one or more" of those qualified may preside.
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All three elements of these supplementary procedures
are meant to work together. The use of a panel will ensure
that expert knowledge is indeed brought to the task of
making a decision. The provision for preliminary written
submissions will allow that panel to screen the issues and
narrow the formal part of the hearing down to those that
are legitimately in dispute and suited to adjudicatory
resolution. Finally, setting a schedule for decision will
help ensure that the potential gains in efficiency represen-
ted by the first two reforms >£re/realized/in practice.
FEB 28 079
Admirtistritor
Dated:
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APPENDIX A
HEARING PANEL
Charles Gregg, Chairperson
William Brungs
Robert Coughlin
TECHNICAL SUPPORT PANEL
Robert Chapman, M.D.
Neil Chernoff
Arnold Kuzmack
Dr. James Lichtenberg
ADMINISTRATIVE APPELLATE PANEL
Ronald L. McCallum
Charles R. Ford
Dr. Edwin H. Clark
Ms. Mary Ann Massey
Dr. Richard M. Dowd
Dr. Stephen J. Gage
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