United States Prevention, Pesticides EPA-738-F-94-005
Environmental Protection And Toxic Substances April 1994
Agency (7508W)
AEPA R.E.D. FACTS
Hexadecadienol
Acetates
Pesticide AU pesticides sold or distributed in the United States must be
Reregistration 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 hi a Reregistration Eligibility Decision (RED) document.
This fact sheet summarizes the information in the RED for hexadecadienol
acetates, including the active ingredients (Z,E)-7,ll-Hexadecadien-l-yl
acetate and (Z,Z)-7,ll-Hexadecadien-l-yl acetate, which are marketed
under the trade name Gossyplure.
Use Profile Hexadecadienol acetates are sex-attractant pheromones of the pink
bollworm, Pectinophora gossypiella. Saunders, registered only for use on
growing cotton to disrupt the male-female mating behavior. They are used
in small quantities-less than 100 pounds of the active ingredients are
applied each year, and only about 1% of the California cotton crop is
treated with these biochemical pesticides. i *
Some products of this pheromone are applied hi retrievably-sized
polymeric matrix dispensers (twist ties and impregnated stakes). There are
also end-use products which are microencapsulated and applied to foliage
via broadcast, ground- and aerially-applications. These are water soluble
formulations sprayed as either tank mixes or alone as emulsifiable
concentrates or water dispersable granules.
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Regulatory
History
Hexadecadienol acetates were first registered as pesticides in the U.S.
in 1978. Currently, 10 products are registered by six companies. The
reregistration case contains four active ingredients, however two are not in
any registered products..
The hexadecadienol acetate formulations classified as solid matrix
dispensers soon may be exempted from regulation as pesticides because
they pose little risk to human health or the environment.
Human Health
Assessment
Toxicity
Hexadecadienol acetates generally are of low acute toxicity. They
are placed hi Toxicity Category IV, indicating the lowest level of acute
toxicity, for acute oral and primary dermal effects. For acute dermal,
acute inhalation and primary eye irritation effects, hexadecadienol acetates
are placed in Toxicity Category HI. Since the potential for human
exposure to these pesticides is considered negligible, all other standard
toxicology studies are waived.
Dietary Exposure
Hexadecadienol acetates may be present in the diet at low levels, but
these residues are considered to be negligible and are not believed to pose
human health risks. An exemption from the requirement of a tolerance has
been established for residues of the active ingredient in or on the raw
agricultural commodity cottonseed when applied to cotton from capillary
fibers (see 40 CFR 180.1043). This exemption does not include the
microencapsulated active ingredient.
Occupational.and Residential Exposure
Since hexadecadienol acetates are contained, embedded or
impregnated in a solid polymeric matrix or shell, cause little exposure, and
do not pose significant toxicological concerns, no exposure data are
required.
Human Risk Assessment
Based on their application methods, insignificant dietary and non-
dietary exposure and relatively low toxicity, the hexadecadienol acetates'
potential risks to humans are considered negligible.
Environmental
Assessment
Environmental Fate ,
Hexadecadienol acetates are highly volatile and rapidly disperse into
air. They are used in minute quantities in impregnated materials (stakes or
twist ties) or as microencapsulated material which is applied to foliage via
broadcast, ground- and aerially-applications. Because there is potential for
the microencapsulated material to reach soil or water, soil or water
contamination is possible. However, since the microencapsulated
hexadecadienol acetate assumes the vapor state as it is released and rapidly
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disperses, the amount which would actually be available in the ecosystem
at any given time would be a small fraction of the amount applied.
Ecological Effects
Technical hexadecadienol is practically non-toxic to bobwhite quail,
rainbow trout and honey bees. It is tentatively characterized as highly
toxic to freshwater invertebrates. However, two aquatic studies are
considered unacceptable and must be repeated as confirmatory data.
Ecological Effects Risk Assessment
Hexadecadienol acetate emulsifiable concentrate residues on treated
food and forage items are expected to be below all levels of concern for
both non-target and endangered avian species. A model used to calculate
the expected environmental concentration (EEC) of hexadecadienol acetate
emulsifiable concentrate in water indicates that adverse effects to aquatic
species would be unlikely. Because it is highly volatile and is used hi very
small amounts, EPA believes that the risk to freshwater aquatic organisms
will be minimal. However, the Agency is requiring acute toxicity data on
both freshwater fish and aquatic invertebrates to confirm this assumption.
Additional Data
Required
The generic data base for hexadecadienol acetates is substantially
complete. However, EPA is requiring additional ecological effects studies
as confirmatory data. 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 of
pesticide products containing hexadecadienol acetates.
Product Labeling All hexadecadienol acetate end-use products must comply with EPA's
Changes Required current pesticide product labeling requirements. In addition:
Protection of Freshwater Invertebrates - All end-use products must bear
the following precautionary statement:
"This product is highly toxic to freshwater invertebrates. Do not
apply directly to water, or to areas where surface water is present or
to intertidal areas below the mean high-water mark. Drift and runoff
may be hazardous to aquatic organisms hi neighboring areas. Do not
contaminate water when disposing of equipment washwajer or
rinsate." '
Application Rates - Product labels must include the amount of active
ingredient to be applied per application, the maximum number of
applications per year, and the minimum number of days between each
application.
Worker Protection Standard (WPS) - Any product whose labeling
permits use in the production of an agricultural plant on any agricultural
establishment (farm, forest, nursery or greenhouse) must comply with the
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Regulatory
Conclusion
For More
Information
labeling requirements of EPA's Worker Protection Standard (WPS). See
PR Notice 93-7, "Labeling Revisions Required by the Worker Protection
Standard (WPS)," and PR Notice 93-11, "Supplemental Guidance for PR
Notice 93-7." Unless specifically directed in the RED, all statements
required by the WPS and reflected in these two PR Notices must be
included on product labeling.
The use of currently registered pesticide products containing
hexadecadienol acetates in accordance with approved labeling will not pose
unreasonable risks or adverse effects to humans or the environment.
Therefore, all currently registered products are eligible for reregistration.
These products will be reregistered once the required confirmatory generic
data, product specific data, revised Confidential Statements of Formula and
revised labeling are received and accepted by EPA.
EPA is requesting public comments on the Reregistration Eligibility
Decision (RED) document for hexadecadienol acetates during a 60-day
time period, as announced in a Notice of Availability published hi 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.
Following the comment period, the hexadecadienol acetates RED
document 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 hexadecadienol acetates RED, or reregistration of individual products
containing hexadecadienol acetates, 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 ha recognizing and managing pesticide poisoning symptoms,
please contact the National Pesticides Telecommunications Network
(NPTN). Call toll-free 1-800-858-7378, from 8:00 am to 6:00 pm Central
Time, Monday through Friday. '
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