United States
Environmental Protection
Agency
Prevention, Pesticides
And Toxic Substances
(7508W)
EPA-738-F-97-001
March 1997
R.E.D. FACTS
Pesticide
Reregistration
Use Profile
4-Chlorophenoxy-
acetic Acid (4-CPA)
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 reregi strati on, 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 reregi strati on, EPA announces this
and explains why in a Reregi strati on Eligibility Decision (RED) document.
This fact sheet summarizes the information in the RED document for
reregi strati on case 2115, 4-chlorophenoxyacetic acid, hereafter referred to
as "4-CPA".
4-CPA is used in the food industry as a plant growth regulator to
restrict root growth during seed germination of mung beans. 4-CPA is
applied to the water bath to soak the beans. Once the beans have soaked for
several hours, they are washed to remove the surface residues, and are then
germinated indoors for several days. After sprouting, the hulls and roots
are discarded, and the remaining portion is packaged and sold for human
consumption.
4-CPA is formulated in end-use products as a soluble concentrate,
liquid, and crystals. It is applied by direct pour or by closed delivery
systems. Use practice limitations prohibit the feeding of bean parts or hulls
treated with 4-CPA to livestock. Contamination of water, food, or feed by
the storage or disposal of 4-CPA also is prohibited.
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Regulatory
History
4-CPA was first registered as a pesticide in the U.S. in 1969 for use as
a plant growth regulator for mung beans, and later as a fruiting bloom set
for tomatoes.
EPA issued a Data Call-In for 4-CPA in 1984 requiring chronic
toxicology data. A second Data Call-In was issued in 1987 to investigate
possible dioxin/furan formation during the manufacturing process.
Under the reregi strati on program, in 1991, EPA issued a third Data-
Call-in for data to characterize the chemistry, human toxicity, and
environmental fate of 4-CPA. Another Data Call-In was issued in 1994 for
the tomato use, which the registrant was no longer supporting for
reregi strati on. As a result, the products labeled for use on tomatoes were
voluntarily canceled, leaving two products labeled for use on mung beans.
Human Health
Assessment
Toxicity
In acute toxicity studies using laboratory animals, 4-CPA is a severe
eye irritant and is classified as Toxicity Category I for eye irritation in
mammalian species. This classification represents the most severe level of
acute toxicity. 4-CPA is slightly toxic through the oral and dermal routes
(Toxicity Category III). It is only mildly toxic through the inhalation route
(Toxicity Category IV) and is classified as non-irritating for primary dermal
irritation. 4-CPA is not a skin sensitizer.
With the exception of ocular irritation, 4-CPA generally is of low
subchronic mammalian toxicity. 4-CPA was shown to be a developmental
toxin causing decreases in fetal body weight and inducing skeletal
variations in rats. 4-CPA did not exhibit mutagenic potential.
Due to 4-CPA's lack of overt toxicity in subchronic dietary studies,
the lack of acute dietary exposure concern, and the low volume/minor use
status, EPA waived the requirements for chronic toxicity, carcinogenicity,
and reproductive effects, which are normally required for food-use
chemicals.
Dietary Exposure
People may be exposed to residues of 4-CPA through the diet.
Tolerances or maximum residue limits have been established for mung bean
sprouts at 2.0 ppm and in/on tomatoes at 0.05 ppm (please see 40 CFR
180.202). However, in response to a petition by the registrant, the Agency
will amend the existing tolerance for mung bean sprouts, lowering it to 0.2
ppm. In addition, the established tolerance on tomatoes will be revoked due
to the lack of support for this use.
Mung bean sprouts are considered a raw agricultural commodity;
thus, food additive tolerances have not been required or established for this
use.
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EPA has assessed the dietary risk posed by 4-CPA. An acute dietary
risk assessment was not required since no acute dietary toxicity end-point of
concern was identified. In the chronic exposure analysis, for the overall
U.S. population and 22 subgroups, exposure from the current 4-CPA
tolerances represents 1.43% of the Reference Dose (RfD), an amount
believed not to cause adverse effects if consumed daily over a 70-year
lifetime. The exposure levels of the two most highly exposed subgroups,
children 1-6 and 7-12 years old, represent 2.62% and 2.24% of the RfD,
respectively. Therefore, chronic dietary risk is not of concern for this
chemical.
Occupational and Residential Exposure
The Agency believes that the potential for exposure to 4-CPA during
pesticide handling operations exists, but is low. Neither a worker exposure
assessment nor a risk assessment were required because 4-CPA generally is
of low toxicity, and the potential for worker exposure associated with
growing mung beans is very low.
Products containing 4-CPA are intended primarily for occupational
use and are not likely to be used at residential sites. At this time, the use of
4-CPA is outside the scope of the Worker Protection Standard for
Agricultural Pesticides (WPS), due to the industrial setting for applying this
pesticide.
Human Risk Assessment
4-CPA generally is of low acute and subchronic toxicity, but is a
severe eye irritant. It also has been shown to be a developmental toxin in
rats. Although people may be exposed to very low levels of 4-CPA in their
diets, this exposure does not pose risks of concern. Since both the
pesticide's toxicity and handlers' exposure levels are low, 4-CPA also poses
only minimal risks to workers engaged in growing mung beans.
Environmental EPA waived most ecotoxicity data requirements for reregi strati on of
AsSGSSITIGnt ^he mung bean use of 4-CPA because this use is entirely indoors, resulting
in practically no exposure to non-target organisms.
Environmental Fate
The results of a hydrolysis study, which was the only data required to
support the indoor mung bean use of 4-CPA, indicated that it is expected to
be mobile in soil and aquatic environments. Any disposal of water treated
with 4-CPA after use on mung beans must be in compliance with a National
Pollutant Discharge Elimination System (NPDES) permit.
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Ecological Effects
Since 4-CPA is registered for use entirely indoors, practically no
exposure to non-target organisms results. The available data indicate that
4-CPA is practically non-toxic to small mammals on an acute oral basis,
and practically non-toxic to warm water fish.
Additional Data
Required
Product Labeling
Changes
Required
Ecological Effects Risk Assessment
4-CPA as typically used indoors in growing mung beans is not likely
to be released to the environment in significant amounts in effluent. Any
exposure to fish, wildlife, or endangered species would be regulated under
the NPDES permit program. Therefore, risk to fish, wildlife, and
endangered species is minimal.
EPA is requiring additional generic preliminary analysis data on one
of the 4-CPA products, and additional product chemistry data on the second
product, to confirm its regulatory assessments and conclusions.
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 reregi strati on.
All 4-CPA end-use products must comply with EPA's current
pesticide product labeling requirements, and with the following:
Environmental Hazard Statement
The following label statement is required on all end use products for
the mung bean use (PR Notice 93-10):
"Do not discharge effluent containing this product into lakes, streams,
ponds, estuaries, oceans, or public water unless this product is
specially identified and addressed in a NPDES permit. Do not
discharge effluent containing this product to sewer systems without
previously notifying the sewage plant authority. For guidance,
contact your State Water Board or Regional Office of EPA."
Personal Protective Equipment (PPE) for Handlers
Due to the potential for eye irritation (Toxicity Category I), EPA is
requiring that handlers of the La Choy 100% product wear protective
eyewear. The following language must be located on the label:
"Applicators and other handlers must wear goggles."
There are no other special toxicological concerns about 4-CPA that warrant
the establishment of active-ingredient-based handler PPE requirements.
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Therefore, the PPE for handlers will be based on the acute toxicity of each
end-use product.
Regulatory
Conclusion
Entry Restrictions for Occupational-Use Products
All of the registered uses of 4-CPA are outside the scope of the
Worker Protection Standard for Agricultural Pesticides (WPS). Therefore,
there are no reentry restrictions. EPA is requiring the following labeling
statements on all end-use products containing 4-CPA that are intended
primarily for occupational use:
Application Restrictions:
"Do not apply this product in a way that will contact workers or other
persons, either directly or through drift. Only protected handlers may
be in the area during application."
User Safety Requirements:
"Follow manufacturer's instructions for cleaning/ maintaining PPE. If
no such instructions exist for washables, use detergent and hot water.
Keep and wash PPE separately from other laundry."
User Safety Recommendations:
"Users should wash hands before eating, drinking, chewing gum,
using tobacco, or using the toilet."
"Users should remove clothing immediately if pesticide gets inside.
Then wash thoroughly and put on clean clothing."
"Users should remove PPE immediately after handling this product.
Wash the outside of gloves before removing. As soon as possible,
wash thoroughly and change into clean clothing."
The use of currently registered products containing 4-CPA in
accordance with approved labeling will not pose unreasonable risks or
adverse effects to humans or the environment. Therefore, all uses of these
products are eligible for reregi strati on.
4-CPA products will be reregistered once the required product-
specific data, revised Confidential Statements of Formula, and revised
labeling are received and accepted by EPA.
For More
Information
EPA is requesting public comments on the Reregi strati on Eligibility
Decision (RED) document for 4-CPA 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.
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Electronic copies of the RED and this fact sheet can be downloaded
from the Pesticide Special Review and Reregi strati on 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
(EPA/NCEPI), PO Box 42419, Cincinnati, OH 45242-0419, telephone
513-489-8190, fax 513-489-8695.
Following the comment period, the 4-CPA 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 reregi strati on program,
the 4-CPA RED, or reregi strati on of individual products containing 4-CPA,
please contact the Special Review and Reregi strati on 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 toll-
free 1-800-858-7378, between 8:00 am and 8:00 pm Eastern Standard
Time, Monday through Friday.
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