United States Prevention, Pesticides EPA-738-F-95-022

Environmental Protection And Toxic Substances June 1995

Agency (7508W)

R.E.D. FACTS

Sodium

Fluoroacetate

Pesticide

Reregistration

All pesticides sold or distributed in the United States must be

registered by EPA, based on scientific studies showing that they can be used

without posing unreasonable risks to people or the environment. Because of

advances in scientific knowledge, the law requires that pesticides which

were first registered years ago be reregistered to ensure that they meet

today's more stringent standards.

In evaluating pesticides for reregistration, EPA obtains and reviews a

complete set of studies from pesticide producers, describing the human

health and environmental effects of each pesticide. The Agency imposes

any regulatory controls that are needed to effectively manage each

pesticide's risks. EPA then reregisters pesticides that can be used without

posing unreasonable risks to human health or the environment.

When a pesticide is eligible for reregistration, EPA announces this and

explains why in a Reregistration Eligibility Decision (RED) document. This

fact sheet summarizes the information in the RED document for

reregistration Case 3073, sodium fluoroacetate, also known as compound

1080.

Use Profile Sodium fluoroacetate is an acute toxicant predacide which is used

against coyotes which prey on sheep and goats. Registered end-use products

are injected into the rubber reservoirs of the Livestock Protection collars,

also referred to as the "toxic collar", which are strapped to the throats of

sheep or goats. Coyotes attempting to kill collared livestock are likely to

puncture the collars and to be fatally poisoned by sodium fluoroacetate as a

result of the attack. When predation is anticipated, up to 20 collars may be

used in fenced pastures up to 100 acres in size; up to 50 collars may be used

in pastures of 101 to 640 acres; and up to 100 collars may be used in

pastures of 641 to 10,000 acres.

Sodium fluoroacetate is a restricted use pesticide which may be used

only by trained, certified applicators and which is only registered for use in

livestock protection collars. Sodium fluoroacetate will retain the restricted
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use classification imposed by the Agency in 1978 due to its high acute

toxicity and the need for highly specialized applicator training. The Agency

also has reviewed concerns about the exposure of threatened and endangered

animal species with the United States Fish and Wildlife Service (USFWS).

The March 1993 USFWS final biological opinion on the effects of sodium

fluoroacetate on threatened and endangered species addressed the livestock

protection collar and included jeopardy determinations to the gray wolf and

grizzly bear. Specific areas were identified where the collar could not be

used and such restrictions have been incorporated on the livestock protection

collar labels. No additional use restrictions to further protect threatened and

endangered species are being imposed at this time.

Regulatory

History

Development and use of sodium fluoroacetate as a predacide and

rodenticide in the U.S. began in the 1940s prior to the 1947 enactment of

the Federal Insecticide, Fungicide, and Rodenticide Act by which

requirements for federal registration of pesticide products were instituted.

In 1964 and again in 1971, the use of poisons to control predatory mammals

were reviewed by selected committees. In 1972 EPA cancelled all

registered predator control uses of sodium fluoroacetate, sodium cyanide,

and strychnine.

In 1977, the U.S. Department of the Interior (USDI) applied for an

Experimental Use Permit (EUP) to investigate the potential risks and

benefits associated with the use of sodium fluoroacetate in "toxic collars"

which would be placed on the necks of sheep and goats. The toxic collar

containing sodium fluoroacetate solution would be positioned around the

animals' throat regions where they would be likely to be ruptured by the

teeth of coyotes that attempted to kill the livestock with species-typical

throat bites.

In 1981, EPA was petitioned by the USDI and livestock interests to

revisit the 1972 predacide cancellation decision with respect to sodium

fluoroacetate. EPA held informal hearings in 1981 and formal

administrative hearings in 1982 resulting in a final decision to permit EPA

to consider applications for registration of sodium fluoroacetate in toxic

collars and single-dose baits.

In 1985, EPA granted a registration to USDI for a toxic collar product

which was transferred in 1986 to the Animal and Plant Health Inspection

Service (APHIS) of the U.S. Department of Agriculture (USDA).

The rodenticide uses of sodium fluoroacetate were cancelled due to

lack of supporting data. In 1989, all "special local needs" registrations
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issued under § 24(c) of FIFRA were cancelled, and all pending applications

for Federal registration were denied by August 1990.

Human Health

Assessment

Toxicity

Sodium fluoroacetate is a sodium salt of fluoroacetic acid which is a

tan colored alkaline powder with a pH of 10.3. It melts at 197-203 C with o

decomposition. It is soluble in water, but practically insoluble in all nonpolar solvents. Sodium fluoroacetate is stable in sunlight, at a temperature

of 54 C, and in tin coated metal containers.

o

The toxicological data base on sodium fluoroacetate is adequate and

will support reregistration eligibility. Sodium fluoroacetate has been placed

in Toxicity Category I, which indicates the highest degree of acute toxicity,

for acute oral toxicity; Toxicity Category II, moderately toxic, for acute

dermal toxicity; Toxicity Category III, slightly toxic, for primary eye

irritant; and Toxicity Category IV, practically non-toxic, for dermal

irritation. The requirements for acute inhalation toxicity and dermal

sensitization studies were waived due to the severe acute toxicity of the

compound.

Sodium fluoroacetate caused dose-related findings in histopathology

and decreased size and weight of testes and epididymides in males in a

subchronic dietary study in rats. In a subchronic study of sodium

fluoroacetate in drinking water of rats, no effects were seen in the kidney or

liver, but testicular atrophy and nonreversible tubular degeneration were

found at the mid-and high-doses. Testicular atrophy with reversible tubular

degeneration was found at the low dose. The metabolism of sodium

fluoroacetate is understood in the mammalian body. It can be absorbed

through the gastrointestinal tract, respiratory tract, or open wounds, but

only slowly through intact skin.

Human Risk Assessment

Because of the specific nature of this registered use, EPA's

primary concern is for the potential risk of acute toxicity. Under the

current limited use pattern, no sodium fluoroacetate exposure to the general

population is expected. Risk of acute toxicity to applicators is mitigated by

the pesticide's use restrictions and its classification as a restricted use

pesticide.
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Environmental

Assessment

Environmental Fate

The Agency has reviewed published literature which suggests that

leaching and metabolism are the major routes of dissipation. However,

undegraded fluoroacetate is considered mobile and consequently has a high

potential to move downward in the soil and reach ground water. While

sodium fluoroacetate has the potential to reach groundwater, the Agency's

Pesticides in Ground Water Database reports no detections for the period

1971 to 1991.

Ecological Effects

The Agency has adequate data to assess the hazard of sodium

fluoroacetate to nontarget organisms. Sodium fluoroacetate is very highly

toxic to the mallard duck, chukar, ring-necked pheasant, widgeon, golden

eagle, black vulture and the black-billed magpie on an acute oral basis.

Substantial chronic exposure to birds is not expected with the use of the

sodium fluoroacetate livestock protection collar. Because the livestock

protection collar is specifically designed to kill a wild mammal (coyote),

wild mammal toxicity testing was required for sodium fluoroacetate.

Sodium fluoroacetate can be classified as very highly toxic to coyotes,

cotton rat, deer mouse, raccoon, opossum and skunk on an acute oral basis.

It is slightly toxic to rainbow trout and practically non-toxic to bluegill

sunfish. Sodium fluoroacetate is practically non-toxic to Daphnia magna, a

freshwater invertebrate. The terrestrial non-food use of sodium

fluoroacetate will not result in substantial exposure to marine and estuarine

organisms, therefore, these data were not required.

Certain nontarget species of birds and mammals, including threatened

and endangered species, may be exposed to sodium fluoroacetate used in

livestock protection collars. Based on a variety of studies that have been

reviewed by the Agency, the principal source of risk is exposure of

scavengers feeding on the head and neck area of dead livestock bearing

sodium fluoroacetate livestock protection collars. Factors that reduce the

risk associated with use of these collars include rapid decomposition of

carcasses, selective feeding of scavengers from wounds on the carcass rather

than contaminated skin surface of the head or neck, and the emetic property

of the chemical. The concerns for risk to wildlife can be addressed by

hazard statements, special use restrictions, and endangered species

protection statements that are required to be placed on the product label.

Additional Data

Required

The generic database supporting the reregistration of sodium

fluoroacetate for use in livestock protection collars has been determined to
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be substantially complete. No new generic data are being required at this

time.

The Agency also is requiring product-specific data including product

chemistry and acute toxicity studies, revised Confidential Statements of

Formula (CSFs), and revised labeling for reregistration.

Product Labeling

Changes Required

The labels of all registered pesticide products containing sodium

fluoroacetate must comply with EPA's current pesticide labeling

requirements as specified in 40 CFR § 156.10 and other applicable notices.

The statements must also appear on the labels of sodium fluoroacetate end

use products consistent with the USDA/APHIS product's 18 use restrictions.

(See "Use Restrictions" in the RED document for the 18 use restrictions).

In addition, the states may add use restrictions consistent with EPA's

regulatory position and legal decisions regarding predacidal uses of sodium

fluoroacetate, but no requirements may be dropped or mitigated. Any

changes to the use restrictions must be requested through the amendment

process and must be accepted in advance by E.P.A.

Regulatory

Conclusion

The use of registered products containing sodium fluoroacetate will

not pose unreasonable risks or adverse effects to humans or the

environment, provided that these products are used in accordance with the

restrictions on product labeling. Therefore, the current use of these

products is eligible for reregistration. Sodium fluoroacetate products will be

reregistered once the required product-specific data, Confidential Statements

of Formula and revised labeling are received and accepted by EPA.

For More

Information

EPA is requesting public comments on the Reregistration Eligibility

Decision (RED) document for Sodium Fluoroacetate during a 60-day time

period, as announced in a Notice of Availability published in the Federal

Register. To obtain a copy of the RED document or to submit written

comments, please contact the Pesticide Docket, Public Response and

Program Resources Branch, Field Operations Division (7506C), Office of

Pesticide Programs (OPP), US EPA, Washington, DC 20460, telephone

703-305-5805.

Electronic copies of the RED and this fact sheet can be downloaded

from the Pesticide Special Review and Reregistration Information System at

703-308-7224. They also are available on the Internet on EPA's gopher

server, GOPHER.EPA.GOV, or using ftp on FTP.EPA.GOV, or using

WWW (World Wide Web) on WWW.EPA.GOV.

Printed copies of the RED and fact sheet can be obtained from EPA's

National Center for Environmental Publications and Information
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(EPA/NCEPI), PO Box 42419, Cincinnati, OH 45242-0419, telephone

513-489-8190, fax 513-489-8695.

Following the comment period, the Sodium Fluoroacetate RED

document also will be available from the National Technical Information

Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161, telephone

703-487-4650.

For more information about EPA's pesticide reregistration program,

the Sodium Fluoroacetate RED, or reregistration of individual products

containing Sodium Fluoroacetate, please contact the Special Review and

Reregistration Division (7508W), OPP, US EPA, Washington, DC 20460,

telephone 703-308-8000.

For information about the health effects of pesticides, or for assistance

in recognizing and managing pesticide poisoning symptoms, please contact

the National Pesticides Telecommunications Network (NPTN). Call tollfree 1-800-858-7378, between 8:00 am and 8:00 pm Eastern Standard

Time, Monday through Friday.